+++ #1194 Subject: Rudder Pedals From: Rod Smith I mounted my rudder pedals to a piece of plywood and was playing with them tonight, I know, doesn't take much to amuse me. I noticed that it was easy for my feet to slip off of them. I think I will either weld some AN970 washers to the ends of the pedals or make some .050 tabs and weld them to the forward side at the ends to make it easier to keep my feet centered on them, especially in turbulence. Anyone else have some thoughts on this idea? +++ #1195 Subject: Rudder Pedals From: Russ Erb > I noticed that it was easy for my feet to slip off of them. The glider I fly frequently has such tabs on the end of the pedals. It makes sense to me, and gives feedback if you're actually on the pedal. The glider pedals sometimes seem too narrow since I have a rather wide (EE) foot. A quick check of the plans and a measurement of my boot shows that width shouldn't be a problem. So were you holding an imaginary stick too? Making airplane noises? So what is your roll rate? How much sideslip did you get? 8-) +++ #1196 Subject: Re: Rudder Pedals From: budd davisson I always put washers on the end of the pedals but I don't use washers. Get some of the freeze plugs used in engine blocks. They come in a bunch of different sizes and are about 3/32 thick and have a nice curve to them. You can mount them slightly off center so they curve out away from the center. They look nice and don't gouge your feet. +++ #1198 Subject: Re: Rudder Pedals From: Tim Anderson I have found the type of shoe one wears has a big impact on rudder feel and connectivity with the foot. I wore those heavy rubber inflatable Bunny boots once (Alaska types will know what I'm talking about), and only once. Wrong idea. Couldn't even feel the pedals. I could have been pushing on the firewall for all I knew. I then switched to Mukluks. +++ #1199 Subject: Re: Rudder Pedals From: budd davisson The subject of shoes comes up all the time in checking people out in the Pitts. There's the old wives tale that you need super thin soles to "feel" the airplane. I always advise against that. I tell people to use what ever it is they normally wear so the feel they get on the rudder is the same they normally get. The only thing I point out is to avoid those kinds of sneakers or hiking boots that have tractor treads for soles. The rougher the sole the harder it is to get the exact position on the rudder becasue the rudder keeps wanting to index into one groove or the other. Besides those kinds of shoes don't work for killing ants either. Incidentally, I tell folks if they want true connectivity with the rudder they should have flying shoes with plywood soles. +++ #1364 Subject: Rudder Cables in Cabin From: Rod Smith Those of you who have gone through Russ's CD have probably noticed the exposed rudder cables running the length of the Bearhawk cabin. Another example of details that I either missed or forgot about since Bob had the plane up here. Russ or maybe it is Pat, makes comments about putting some kind of cover over these. I'm thinking instead to drop the cables from the rudder connections at about a 45 degree angle through the floor to a pulley on each side. From there they would run under the floor through fairleads back to the rudder. You would have the extra weight of the pulleys but it probably would be less than any covers you could devise as they would need to run the full length of the cabin. A lot of planes run the rudder cables under the floor. I will double check with Bob before pursuing this further. +++ #1366 Subject: Rudder Cables in Cabin From: Russ Erb > I'm thinking instead to drop the cables from the rudder connections at > about a 45 degree angle through the floor to a pulley on each > side. From there they would run under the floor through fairleads back > to the rudder. I think this is worth considering. I don't like the rudder cables out where my kids could bump or pull them. As for inspecting, I'm thinking that during the annual inspection the seats will come out and the floor will come up to inspect all of the cables and mechanisms. 45 degrees might be too steep. I'd shoot for just enough to get it under the floor before getting to the rear seat area. But I haven't looked at the structure to see what would be the easiest angle. Besides, the elevator cables are under the floor already. +++ #1379 Subject: Re: Rudder Cables in Cabin From: Tim Anderson I haven't had the prevledge of seeing the bearhawk first hand but... An option for covering the exposed cables in the cabin is to put a plastic tube over the cable with the ID slightly larger than the cable and attaching the plastic tube to "something" (not sure what) to keep it in place, kind of like a conduit. That will give the exposed cables some protection from being kincked, jammed, stepped on, etc. +++ #1381 Subject: Re: Rudder Cables in Cabin From: Pierce Terry Civ 412 TW/TSI The Stinson 108 series has the rudder cables running under the floor. They did come out with an AD to either regularly inspect the cable where it runs under the forward turning sheave or to increase the size of the sheave. I can dig out particulars (original/modified sheave sizes, etc.) if anybody is interested. Running the cable through a tube would require that the cable be disconnected and pulled out of the tube for the occasional inspection. I guess you pays your nickel and makes your choice. ;-) +++ #1736 From: William & Delinda Johnson Subject: [Bearhawk] 023 Update I am now working in the main cabin section. Web site is updated with pictures. Press refresh when you get to the main page to get the latest. The stick assembly took 3 days to make. Alignment of the stick support brackets, distance between sticks, making sure the cross linkage clears the cross tube wall, etc made the work slow. The support brackets took way too long for me to make but they turned out great. I am pleased with the results. +++ #1814 Float-By Shooter Subject: [Bearhawk] powdercoating/control bearings > On a Bearhawk, everything that's welded could be powdercoated, but the > comment about the bolt holes, etc, is a good one. I've never tried it, > but I'm certain the powder coaters have some sort of masking procedure > to protect holes and certain areas. You could pound wooden dowls in > holes you want kept clean and mask areas where tubes slide inside one > another and just chromate those afterwards, as powder coating can be > thicker than paint. Has anyone out there had this experience? I use the Eastwood powder coating system made for home/small shop use ($150) and they sell heat resistant plugs for holes that you don't want coated. They also have a heat resistant masking tape which works very well. I really like the system and the finish it leaves, but I am not sure if it will be useful for a lot of the Bearhawk parts, especially those that have one tube moving inside another, as in the control system. On many of these parts they have to be welded together before any finish is applied, and I'd be afraid of the powdercoating immobilizing the moving parts. It's probably something that can be worked around, but I haven't experimented with it yet. One further question: On the flight controls, holes for dripping oil into the bearings are shown (and can be seen on W. Johnson's pictures). I was wondering if it would be worthwhile (or even desirable) to install grease fittings in these locations instead. My thinking is that grease might be a little more tenacious than the oil which is always a plus in my climate where condensation is a big worry. +++ #1821 From: Bruce A. Frank Subject: [Bearhawk] Re: powdercoating/control bearings I think a grease fitting a good move, BUT use only the types that remain "fluid" at low temps. I think those used in 'copter rotor heads fit the bill (Mobil 28 is one I know). +++ #3346 Subject: Re: [Bearhawk] Wing Iron Question and #433 update From: I am incorporating zerk fittings on my stick and rudder pedal assemblies, and even stuck some on the trim arm bearings. Haven't yet decided if I will make the trim ones accessable after covering, but at least I can give then a good shot of grease initially. Zerks are easy to add, and I like the idea of grease better than dribbling oil in that little hole. I have gone ahead and sent a deposit and gotten on the waiting list for a Barrow's built O540. Delivery expected in May. He said it will be the first one he's built for a customer Bearhawk. What an honor. +++ #3402 Subject: Re: [Bearhawk] Control Stick Towers From: The new control stick towers are slanted at a steeper angle, but the sticks remain 18" apart. To compensate for the change, Bob has shortened the tube that the stick towers attach to. The link tube that connects the sticks remains the same length. This allows all the hardware to remain outside the tower tube, avoiding the use of a rivet. The bearings are consequently moved closer together as well. Sorry about my last post on the rivets. Guess I need to read the question a little closer so that I understand what is being asked. +++ #3415 Subject: Re: [Bearhawk] Gross Buffoonery Slows Down Progress From: Kent White > Now, just imagine that you cut out these gussets between 6 months > and a year before you actually install them, and store them in one > pile. Can you see where a problem might creep in? > > If you're thinking that you might forget that there are two > different thicknesses, then you're far more perceptive than me! When laying out and blanking parts for use later, always mark them left, right, up down, and thickness, if there are variations. I have made many blunders over the decades for lack of written guidance on the parts, even after a weekend away from the shop. +++ #4003 From: Steve Eldredge Subject: Bending the control stick towers I may be going about this the hard way, but I have cut and finished the pattern for the two control stick towers, and now I am faced with making very accurate bends in order that the bolt holes will line up (as yet undrilled). Any suggestions about how to get the accuracy I need, and what order to make the bends? Control horns and hinges bent. thanks for any techniques... +++ #4016 From: Pat Fagan Subject: Re: Bending the control stick towers I have found the simplest and most reliable way for me is to bend up the metal, then put in my bolt holes. I don't have enough faith in my ability to drill the holes first and bend to match. As for sequence of events, I bent the major U shape, then hammered over the flange. Did you get the revised drawing of the stick towers from Bob. He drew them at a steeper angle to the cable cross tube to reduce the interference of the bolts on the cable connector. +++ #4419 From: Russ Erb Subject: What! Heresy! Yep, the major proponent of "Build it per plan!" is proposing a change to the design. This one is fairly simple, though. The impetus: 1. The control sticks are fabricated of T14 tube, which is 7/8 x .049. As can be seen on the Bearhawk CD, in Proto I the right stick is removable. A tube, presumably 1 x .065, reamed to fit, welded to the top part of the stick slides over the horizontal part of the assembly and is held in place with a bolt. This option allows more options by being able to easily remove the stick. 2. The stick grip I'm considering using is the 90% size F-4 stick grip made by Infinity Aerospace (http://www.flash.net/~infaero). They come in left and right handed versions. As it comes, the stick grip fits a 1" tube. An adapter is available (about $9) that allows the stick grip to be mounted on a 7/8" tube. Put these two thoughts in the big cyclotron and smash them together and what comes out? That's right--the idea that with proper technique, aluminum and steel can be grown in Virginia. Looking further, one also finds the idea that if the upper part of the control stick is made from 1 x .065 (actually T19), two benefits are realized. The stick grip can be attached without an adapter (lower parts count, one less thing to break/screw up), and the stick can easily be made removable with less complexity. Of course, there's always a downside to any modification. I figure there will be an increase in weight of about 7 ounces (just under half a pound) after doing this to both sticks. I think I'm ready to accept this reduction in useful load. I'll just have to tell Planter Bob to leave the Rand-McNally Road Atlas behind and fly VFR instead of IFR (I Follow Roads). +++ #4422 From: Del Rawlins "Float-By Shooter" Subject: Re: [Bearhawk] What! Heresy! Plus according to the website you provided the grips weigh 12 oz each, but I'm sure some of that will be gained back in the form of fewer switches on the panel (because they are built into the grip). If you actually use the switches you'll also have to come up with some kind of quick disconnecting connector(s) for the wires since you plan to make the sticks removable. +++ #4424 From: Russ Erb Subject: Re: [Bearhawk] What! Heresy! No real weight savings in the switches, since all but one of the current planned uses (Flip Flop Comm 1, Flip Flop Comm 2, Transmit Swap, Ident, PTT, and autopilot disconnect) are duplicated in the boxes they control. No problem with disconnecting the wires. The wires will come out the bottom of the vertical portion and proceed to a Molex connector. Similar connectors to be used elsewhere in the airplane, such as at the wing root to allow wing removal. Come to think of it, the larger tube in the stick will help offset any loss of strength from the hole for the wire. +++ #4434 From: Kevin Deutscher bearhwk272@a... Subject: Re: [Bearhawk] Stick Mods and Wires Not to be a bomb thrower but, OK so you monkey with the plans for a removable stick, I can live with that, you have thought most of it out well, except I think that you are going to obtain a small amount of future difficulty. Now bear with me for a minute there are two issue at hand, these are not jokes I am not trying to be a comic especially when there is a full moon out. 1. The grip. A real Bearhawk pilot would only settle for a FULL SIZE GRIP not 90%. The reason is not the grip, the reason is the switches! The grip is GOOD and the switches are OK but here is the wrinkle. The last time I checked these switches were not gold plated contacts. ( Well aren't we being a little extravagant) So what's the rub? That's it, rubbing, fretting, chafe of the silver or cad plated contacts. Aircraft vibrations cause the above, then the contact surface has an oxide coating, not a very good conductor. If you were using the switches to activate flaps, gear, trim, that would be OK because those control circuits have enough current flow to cause a spark across the contacts at activation. This arc cleans the contacts. Avionics are typically a logic or sense circuit, they do not provide a current flow capable of cleaning the contacts. The end result is your radio does not know that you did a PTT and center gets hot cause you ain't talking to them. Avionics - always sealed gold contacts! JMHO. 2. Stick with a good Mil-C circular style sealed type of connector for the avionics junctions. Gold plated pins, sealed to keep out moisture, this is the same moisture that condenses in your fuel tanks when you decend causing water in the fuel and rust in your longerons. The last thing you need on a night approach 1/2 mile vis, 300 ft ovcst, light rain, leaky windshield, sweaty palms is a Molex connector. I will hook up power and lights with a Molex but not avionics. JMHO +++ #4439 From: Russ Erb Subject: Re: [Bearhawk] Stick Mods and Wires > 2. Stick with a good Mil-C circular style sealed type of > connector for the avionics junctions. Okay, Kevin, so where would someone get such a connector, and how much would I have to mortgage the house for? Not saying I will follow your advice, but I will always consider it. You speak of failure modes, but I submit that another solution to guarding against failure is multiple solutions. All of the switches I currently plan to use are duplicated on the panel and the other stick, with the exception of the PTT which is just duplicated on another stick. Just another philosophy concerning reliability. +++ #4692 From: pfflyerz@c... Subject: digging out from under the pile of postings Couple of clarifications on Russ's comments on my progress. As to the seat/stick interference, not really sure it is a problem yet, as I don't know where neutral stick position should fall yet. Had considered rebuilding my sticks with a slightly longer horizontal section, but may cut down the seat bottom if interference is a problem. They are also very tight as far as width. I think I have mine to where they can slide beside each other with only minor modification to the seat back attach points, but I won't really know until I upholster them. I made my elevator horn-to-stick link to plans size, but measured Bob's link on Proto II and found it to be almost an inch longer. Won't know whether that makes a difference until I try running some cables. +++ #4894 From: Pat Fagan pfflyerz@c... Subject: brake lines I've been putting together a shopping list for a trip down to Spruce and was looking into brake line parts and fittings and came up with some questions. 1) On Russ's Bearhawk CD, Landing gear photos Part 2, 7th photo down is a shot of a hard brake line running under the floor and into the top of the landing gear strut. Since the landing gear pivots, shouldn't we use a flexible hose in this area, or is this acceptable? 2) Bingellis talks about using Nylaflow tubing instead of aluminum tubing. Since Bob Barrows is such a stickler for weight and cost I am surprised he has made up Aeroquip hoses to connect the pedal cylinders to the master cylinder if Nylaflow tubing is an alternative. Can Nylaflow be used throughout the brake system? 3) I intend to have both pilot and co-pilot brakes as well as a parking brake valve. In drawing up a plumbing schematic I was wondering where to T the two systems back together, before or after the parking brake valve? I would like to connect them prior to the valve so the parking brake can be applied from either position, but I don't know if the system will work that way. Any insights anyone can provide will be appreciated +++ #4895 From: Russ Erb Subject: [Bearhawk] brake lines I'm far from an expert on this, but here are a couple of thoughts, worth about what you paid for them. 1. In the same photo, you'll see a rather large z-bend that would seem to flex with the landing gear leg. The amount of movement in this area will not be much, but I think I would be more comfortable with some flexible tubing here. However, that makes more places for leaks. 2. I don't know about at the pedals, but I can tell you a reason to avoid nylaflow near the actual brakes. Many years ago a friend landed his RV-4 here at Edwards and while making the about 2 mile taxi in (yes, you read that right--it may be longer), proceeded to melt the section of nylaflow attached to the caliper. (He's since learned to taxi without so much brake). The pictures of the prototypes show metal brake lines in this area. Just be sure you route them such that you can remove the caliper and replace the pads without disconnecting the brake line. +++ #5169 From: Benton Holzwarth Subject: Lancair IV-P - top hinged rudder pedals ... I'll comment on one interesting (to me) bit here. This plane has the rudder pedals hinged from above, rather than at the floor. Some people remarked that this 'action' was actually more comfortable and allowed greater motion than the floor-hinging. My first thought was to recall a story told to me by a bus driver long ago, about carreening along a road, unable to apply brakes because a pair of binoculars had decided to park themselves behind the pedal. Looks like this top-hinged design would resist getting things wedged behind the pedals. It was set up with toe brakes (and a quick read of the Bearhawk plans confirms Bob also went with toe brakes.) Thoughts? My mantra is "keep it simple, get it flying" and I'm not going to change things before I get 'em built for the first time, but hinging the pedals from above really seems to tidy up the floor. (Now about those side-sticks...) +++ #5170 From: Bob Romanko Subject: RE: [Bearhawk] Lancair IV-P - top hinged rudder pedals Ahem...back to rudder pedals with the hinge on top. I like the idea, and looking at Erbman's Bearhawk CD(s) it seems "doable". Of course, it would add weight and violate Rule #1 in building a Bearhawk. Rule #2 is probably flying the thing higher than 19 square (grin). As far as a side stick, in a plane like the Bearhawk that is just flat not natural. It's like a metalized Tri-Pacer. Just shouldn't be done. If God had meant for planes to have side sticks he wouldn't have made our legs so long with one on each side, right? +++ #5175 From: Russ Erb Subject: RE: [Bearhawk] Lancair IV-P - top hinged rudder pedals T-38s have top hinged rudder pedals. F-16 pedals barely move. C-130 pedals move in a direct translation. Schweizer 2-33 and Blanik L-23 pedals are hinged at the bottom. Front cockpit pedals in the Grob 103 and ASK-21 are hinged at the bottom, and rear cockpit pedals move in translation (as best I recall). Based on this vast experience: Short answer (repeat after me): Build to the plans. The modification isn't worth it. Justification: The top hinged rudder pedals have two apparent advantages. One is that the pedal moves in more of a translational motion instead of a rotational motion. The other is that the brakes are somewhat easier to operate since that motion is hinged at the bottom instead of halfway up the pedal. In cruise flight, you'll never know the difference, since you're only moving the pedal maybe 1/2" at the most. The only place you'll notice a difference is on the ground or in slow flight. In any of the gliders listed above, the rudder is going stop to stop in the first part of the takeoff roll and late in the landing roll. I've done both without noticing a difference. In some ways, in that case I prefer the bottom hinged pedals because an ankle motion will give full throw. With top hinged pedals you pretty much have to move your whole leg, which can be sporting if you didn't move the seat up quite enough. On takeoff roll is not the time to discover that. As for Bearhawk braking, I studied Pat Fagan's pedals and saw that because of the geometry, as you push a pedal in, the brake pedal remains vertical or comes toward you, so there is no trouble reaching the brake if you need to. Maybe we should develop a Bearhawk mantra-something like face Fincastle and repeat: 1. Build it to plan 2. Don't add weight 3. Quality first 4. If you think you have a way to "improve" the design, refer to rule #1 Of course, I've already violated all but #3 at some point... +++ #5654 From: "Tim Anderson" Subject: Fwd: Re: Trim Wheel Design Fault Just picked this up from the Skywagon group. May be of interest for those that intend on using cessna trim wheel . I seem to recall that on the BH prototype, the trim wheel apparatus was covered with fabric, maybe I'm wrong...which would make periodic inspection a bit difficult, unless you want to cut and repatch the fabric. Maybe install a removable alum access plate in the ceiling. Well "down the road" for many of us. Tim #398 >From: "Douglas C. Marsh" >To: Skywagon Discussion List >Subject: Re: [Skywagons] Trim Wheel Design Fault > >Chris: Having been in the aircraft salvage business for 15 >years, almost every 180/185 that we dismantled, had loose roll >pins and or a galled shaft. I replace the shaft and all the >roll pins on every 185 I rebuild. The end bearings need a >close look also but usually are ok. The wheel to shaft roll >pin is easy to check on a 100 hour or annual. The shaft >galling is a bit hard to detect but by removing the r/h bearing >support you can check it easily. I have never kept one of the >rebuilds long enough to know how many hours it takes to get >loose or galled. I would however recommend everyone take a >close look at theirs next inspection, it is definitely a weak >spot. > >Doug Marsh >N185MT +++ #6447 From: rsmith@a... Subject: Trim Wheel Location and Skylight Would like opinions on relocating the trim wheel from overhead to between the seats, next to the flap lever. That is where I am used to having it, and that location makes sense to me as you usually make a trim adjustment after changing flap position. Downside is it will be a heavier installation due to addition of 2 pulleys each at stations D and F and larger brackets to accomodate them. The other reason for moving it from the overhead is I am still contemplating a 1/8" plexiglass skylight, full width of the fuselage extending back to the rear spar. To me that is a safety consideration, being able to see into the turn while into a steep bank. Also I like to be able to look up and behind me while climbing. Small plane traffic is pretty heavy off of the lakes just to the east and west of mine plus the 3 or 4 nearby private strips and there is no set traffic pattern. Of course downside to a skylight again is added weight. It will need some framework, considering 1/2 x .032 channel, total installation would add about 7 pounds. I'm still undecided. Rod Smith #246 Wasilla, AK +++ #6448 From: "Bill Cox" Subject: Re: [Bearhawk] Trim Wheel Location and Skylight I'm pretty well committed to the skylight between the spar carrythroughs. My original plan is to leave the trim wheel where it is since I'm used to flying Pipers with the trim in the ceiling. I'm undecided about a one piece skylight with the trim cables exposed or a two piece with a fairing over the cables. I have flown Cessnas with the 2 piece and a Tailwind with a 1 piece. I like the 1 piece better. I will trade a few pounds for the safety. Traffic can be heavy in this local area and I am constantly aware of how blind My Pacer is. The trim wheel on the floor should work out similar to an early Maule. It just wouldn't be as simple as what Bob shows. Bill Cox #303 +++ #6449 From: Budd Davisson Subject: Re: [Bearhawk] Trim Wheel Location and Skylight Opinions: Trim wheel location works fine, as is, and makes for a nice straight run. If you have a skylight, it will be seen, but wouldn't be objectionable Skylight is a must for everyone. One of the first things you notice, when flying the airplane, is that you sit much further back in the wing than you do on something like a C-172 so it is impossible to lean forward and look around the wing. In a turn, you'd be able to look over the wing with a good skylight. It'll take some cleaning up of some of the installation stuff like trim system, but that shouldn't be hard. bd +++ #6450 From: "W. Shalm" Subject: Re: [Bearhawk] Trim Wheel Location and Skylight I know we've discussed tinting/shades etc. for skylights before. A rule of thumb in determining heat and light gain according to my local Velux residential skylight dealer is that in their application, a skylight lets in 5 times as much light as a side window of the same size. I put 4 - 16"X48" skylights in our entrance way that faced north (almost no direct sun exposure) and we almost had to put in a sprinkler system it got so hot--and that is way up in Ontario. I'm planning to use a large skylight in the Christavia Mk IV but with tint and shades. Warren +++ #6451 From: Budd Davisson Subject: Re: skylight shades someone mentioned shades for skylights and they are a near-must. This is especially true in our area. I had a long string of 195's some with and some without the overhead windshield shades, and you almost couldn't fly on sunny days without the shades. the most practical shades I've seen have been of two varieties: a transclucent white material that was on a spring loaded roller exactly like apull down window shade that was mounted on the back of the sky light and pulled forward to hook at the front. 195's had sliding metal shades that came in from the side. bd +++ #6452 From: "Tim Anderson" Subject: Re: [Bearhawk] Trim Wheel Location and Skylight Anyone know of likely sources of Cessna-type trim wheels? I seem to recall that's what Bob used. Surprised he didn't make his own. I guess salvage yards would be a likey place to puruse, haven't seen any mail order sources. The skywagon email group a while back chatted about the roll pin being a source of concern if not regularily checked/maintained at annuals. Tim +++ #6455 From: "DANFORD, GARY" Subject: RE: [Bearhawk] Trim Wheel Location and Skylight Check with Dan Brown (B&B Aircraft Supply) in Gardner,Ks. He has a great stock of Flap/Aileron hinges and he had the Cessna Type trim wheels. He also has a huge supply of other parts. I seen wiring, all kinds of fittings, brake cyls, etc ect ect. You usually see him at Sun and Fun and Oshkosh. He is the vendor with the tables full of wooden trays loaded with fittings, bolts, nuts ect ect. Gary B & B Aircraft Dan Brown 913/884-5930 +++ #6459 From: Benton Holzwarth Subject: B&B Aircraft (was: RE: Trim Wheel Location and Skylight) takes you to a query form. Didn't see any online catalog. Also, going up a level gets you to an av-related business directory that I'd never run across before. Benton 8jun01 +++ #6463 From: pfflyerz@c... Subject: Re: [Bearhawk] Trim Wheel Location and Skylight I had been waiting to make an announcement, but since you brought it up, I am happy to announce that I have completed the modifications on my trim system and skylight and am very happy with the results. I spent a LOT of head scratching time working out the details of the skylight. Part of the problem is the hump that Bob has on his two aircraft (see Russ's CD). Fitting a skylight to the hump would be problematic. I finally realized that the hump is only there to allow room for the large Cessna trim wheel. Design a different trim system and you can run a window even with the tops of the wings. I used to do a lot of glider towing in a Bellanca Scout and always liked the trim lever it used. It was possible to fly the airplane in pitch using the trim control instead of the stick. I have actually landed the Scout without my hand on the stick just to see if it could be done, the trim tab was that responsive. I thought I would like to have the same capability on my Bearhawk, elevator cable failure, no problem. I made up a trim lever that mounts to the back of the large tube between the front spar mounts. A pushrod then goes to a bellcrank mounted to a bracket welded to the tubing "X" between the main and rear spar. All of this mechanism is hidden by an aluminum console that is about 6 inches wide (side to side) and rises to meet the skylight panel. There is room in the console for mounting cockpit/ courtesy lighting or even the intercom jacks. Without the large trim wheel I was able to make my skylight even with the upper wing surface and run it from longeron to longeron. You could make the skylight back to the rear spar, but I chose to terminate mine at the tubing "X". This puts the back of the skylight just behind the pilots head, which should provide enough utility. Modifications for mounting the skylight include: Welding a strip to the top of the windshield top channel to mount nutplates for attaching the front of the skylight. Welding an approximately 2 inch tall channel, with nut plates, to the top of the tube the trim lever is attached to. This serves a midpoint platform and attach point for the skylight and also a mounting surface for the trim console. Welding a 3/4 inch tube between the longerons and the "X" member. To this tube is skip welded an approximately 3 inch tall bulkhead with a groove similar to the one the front windshield slides into. This makes the rear wall of the skylight box and also provides an attach point for the trim console. A half X half inch angle skip welded to the wing contours on both longerons to provide a groove for the skylight panel. My skylight panel will slide into these grooves, from the front, and will be attached with a strip over the windshield/skylight junction, and another 6 inch wide strip, from front to rear, over the trim console. A couple of unforseen but useful results of this system are: An extra handhold for climbing into the front seats. The forward tubes of the "X" are no longer covered by the ceiling fabric. I intend to use sight gauges and discovered in fitting my tanks that the first third of the gauge is hidden under the ceiling fabric. With the open skylight box the entire sight gauge is visible. Pat "happy to finally have that problem out of the way" Fagan #232 +++ #6469 From: Budd Davisson Subject: Re: [Bearhawk] Trim Wheel Location and Skylight A couple of questions/comments. I went back to airbum.com and looked at the photos in 180 BH pirep (original 1995 BH article) of the airplane from the top/front and it looks to me as if there's a strong possibility that the reason the top of the cabin has a hump in it is to continue the hump line that goes back down the fuselage over the back seat. Have you looked at the line of the stringers that define the top of the aft fuselage and how they are going to run into the top of the front cabin. The hump in the top of the fuselage truss to give rear head room is an unusual fuselage layout and I suspect the rear/top stringers are situated to clear that and run in an uninerrupted line to the front of the airplane. In that picture, it also becomes extremely clear that putting a clean, good looking skylight in that area the way The Bob has it faired would be a real challange. Flattening it out would be a better option, if it can be done. It's unclear from your description how your trim lever works. The citabrias had the trim on the left side panel but the Champs had them as a sliding knob that moved fore and aft in the ceiling. On landing, you just slapped it all the way back and you were automatically on glide speed. Can you clarify the actuation system for us? Obviously you've looked at all the alternatives: How far would the trm wheel have to be moved down to get the chain/cables inside the wing line, even though the outter diameter of the wheel would still protrude? I was thinking, if it did't have to come down so far that the cables became a headroom problem, a simple teardrop fairing could be made of aluminum, glass or even Plexi to cover the top of the wheel. Also, what about rotating the wheel 90 degrees, so it lays flat and putting a knob on it so its like a Piper crank and run the cables flat to the ceiling? Just running them through a vertical fair lead at the back of the skylight (or use pullies) would put them into a vertical orientation of the rest of the trim to the tail, although, since they twist together, that's probably not even important. I think I like this option best although I have always had a deep, unbridled hate for Piper crank type trim systems. bd +++ #6472 From: pfflyerz@c... Subject: Re: [Bearhawk] Re: Trim Wheel Location and Skylight > scan some photos of the trim lever and mechanism and post them > to the Bearhawk files? I'll see what I can do, it appears as if our camera has gone south for good and I haven't looked into replacing it yet. <> Of course a picture would be best but the closest thing I can think of would be the overhead throttle arrangement on an amphib. It moves for and aft and has about a 4 inch swing. Don't know if this will allow the flight precision of the Citabria, but it will be close. That is the reason for the horizontal bellcrank, to slow down the movement and keep the roofline low. The fairleads past the bellcrank are arranged like Bob's. This won't make any sense without a picture, but I made a friction device on the trim lever that I can adjust the friction with a nut so I won't have to twine my cables. As for the stringers, they begin at the back of the skylight box. One problem with extending the skylight back to the rear spar is that the window is starting to curve back down so the stringer height will begin that much lower. I think my line will look very close to Bob's at that point on the fuselage. I like the "Black Bearhawk" analogy. Pat Fagan +++ #6708 Date: Sat, 30 Jun 2001 16:42:22 EDT From: pfflyerz@ Subject: throttle/prop controls Could someone with access to a C182 or other plane with a similar throttle arrangement as that on Protos 1 & 2 do me a favor and measure the spacing between controls? I want to weld the tabs on the crossbar for throttle, prop, and mixture, but don't know how far to space them apart. Much obliged. Pat Fagan #232 +++ #6719 Date: Sun, 01 Jul 2001 22:49:22 -0000 From: lglenn4@ Subject: Re: throttle/prop controls > Could someone with access to a C182 or other plane with a > similar throttle arrangement as that on Protos 1 & 2 do me a > favor and measure the spacing between controls? SPACING IS 1.5 INCHES FOR THROTTLE, PROP, & MIXTURE. ROY GLENN #274 +++ #6966 Date: Fri, 20 Jul 2001 21:00:05 -0800 From: "Float-By Shooter" del@ Subject: dual brakes A conversation with a friend has got me thinking I might want dual brakes on my Bearhawk. Would that be as easy as adding a second set of pedals and cylinders to the right side rudder pedals, and then plumbing the 2 sides together with "T" fittings, or am I missing something? Del Rawlins-- +++ #6968 Date: Fri, 20 Jul 2001 23:09:23 -0700 From: "Bruce A. Frank" bafrank@ Subject: Re: dual brakes Check out the diagram in the Aircraft Spruce Catalog. You plumb the left side cylinders through the right side cylinders. Bruce A. Frank +++ #6979 Date: Mon, 23 Jul 2001 06:18:17 -0000 From: slester@ Subject: Re: dual brakes > A conversation with a friend has got me thinking I might want dual > brakes on my Bearhawk. Would that be as easy as adding a > second set of pedals and cylinders to the right side rudder pedals, > and then plumbing the 2 sides together with "T" fittings, or am I > missing something? If you do as you said below, pushing on one pedal will just push brake fluid into the reservoir of the other pedal for the same wheel. You need a set of each style of brake cylinders: one set with reservoirs, another set without reservoirs. Plumb the outlet of the set without reservoirs to the brakes. Plumb the outlet of the set with reservoirs to the inlet of the set without reservoirs. The set with reservoirs become the reservoirs for the set without reservoirs. Pushing the pedals on either set will pressurize the brakes. When you push on the set with reservoirs, the fluid between the set with reservoirs and the set without will depress the pistons on the set without reservoirs, thereby pressurizing the fluid between the cylinders without reservoirs and the wheel cylinders. When you push on the set without reservoirs, they will draw down the piston in the set with reservoirs. +++ #6988 Date: Wed, 25 Jul 2001 05:33:57 -0000 From: avi8r@ Subject: BRAKES I have always had trouble with the operation of the brakes due to an ankle injury. As a result I have been considering using dune buggy style steering brakes with the lever(s) in-between the seats. Other than the name "dune buggy" why wouldn't it work? PAUL +++ #6989 Date: Wed, 25 Jul 2001 01:46:52 EDT From: bearhwk272@ Subject: Re: BRAKES The brakes will work fine. How you manage to do it and keep everything fast and straight is beyond me. I have not seen a single brake handle unit in a tail dragger. Piper did do it from below the panel with a hand operated lever in early Tri Pacers and 140,s. Seems the Britt's did it in the WW 2 era with pneumatics in a tail draggin bomber. Kevin +++ #6992 Date: Wed, 25 Jul 2001 00:26:11 -0700 From: "Bruce A. Frank" bafrank@ Subject: Re: BRAKES >The brakes will work fine. How you manage to do it and keep >everything fast and straight is beyond me. The dune buggy brakes with which I am familiar use either two levers close together that allow easy modulation with the ends of both levers in the hand at the same time. The other design uses a single lever that moves forward and back or up and down, depending on mounting, allows left and right movement from centerline to bias braking at the while applying force needed to stop (sort of like a joy stick in a video game). I have never been inside this type so I don't know how the biasing is accomplished. Bruce A. Frank +++ #7042 Date: Fri, 03 Aug 2001 17:39:00 -0000 From: zipppydoggg@ Subject: Re: BRAKES > I have never been inside this type so I don't know how the > biasing is accomplished. Bruce, I'm familiar (and have owned and used) the two hanle type. It operated just like the dual brake set-up for airplanes. A brake line from the main brake pedal master cylinder enteres both the left and right cylinder of the "two handle dune buggy cutting brake system". Just pull one or both handles. When force is applied with by foot both rear dune buggy brakes are applied equally. It has been my experience that the single handle model can apply pressure to either rear brake, but not both at the same time. I may not be aware of a model that works as you describe, however. I suppose the two handle model would be a suitable brake alternative, allowing either or both brakes to be used. Probably best mounted under the throttles or between the seats. Rob "pumped up to get back to work after AV" Gaddy +++ #7109 Date: Fri, 10 Aug 2001 23:34:17 -0000 From: snorttheoneandonly@ Subject: Stick Position Hi all, Was wondering if anyone is trying any "different" stick position(s) for their Bearhawk. I would like to have it in the middle of the cockpit; me on the left with the stick next to my right leg. I saw the Zenith high-wing planes, 701 and 801, with a strange control stick with a V-handle on the top for the pilot from either side of the cockpit. I just feel like that having the stick (how do I put this delicately?) between my legs is a bit ergonomically unnatural after awhile. My right arm would feel more natural just to the right of my right leg, and then also have the throttle somewhere on the left side of the panel (or even up from the floor on my left). Alright, I'm fussy, but can it be done without a major re-working of the plans? John Walsh +++ #7110 Date: Fri, 10 Aug 2001 16:47:30 -0700 From: Budd Davisson buddairbum@ Subject: Re: Stick Position In the course of my nefarious flying career, I think I've handled just about every stick configuration there is, from side sticks (BD-5, EZ's, etc) to central mounted sticks, as you describe (Bolkows, Tailwind) to upside down "J" sticks (S-11B) to sticks hanging from the overhead (Gyro copter) and sticking out of the extreme end of the panel like a yoke with only one spoke of the wheel attached (Questair). The reality is that you can acclimate to absolutely anything but some have more advantages than others. The normal stick positions allows you to rest your forearm on your knee which gives finer control and less fatigue while on X-country. This, of course depends on how well the control profile is set up. Some airplanes absolutely require you to "hang on" to the stick because you need to make large movements. One thing that has to be taken into account is the way your arm articulates: as you pull back, your elbow has to go out and there is a tendency to bias the stick in that direction. If you move your point of contact with the stick towards the middle of the airplane and it still requires the same amount of movement which it would, if mounted between your legs, you'll have a difficult time getting used to the way you have to move your arm to efface straight pulls, as the elbow movement will be much greater and may run into clearance problems. This is why most central mounted sticks have some sort of protrusion that places the point of contact between the knees (lots of room here for things like "...just the way it feels best" said with a sexual overtone). There's a reason most airplanes have the stick in between your legs and it has nothing to do with naming it the "joy stick." It just happens to work best that way. bd +++ #7111 Date: Fri, 10 Aug 2001 18:45:28 -0700 From: Russ and Penny Erb erbman@ Subject: RE: Stick Position A general comment since I haven't flown an actual Bearhawk yet: For most phases of non-aerobatic flight, the amount of stick movement required is quite small. As a result, your legs don't tend to get in the way. Large motions are mostly needed at low speeds like those high-crosswind takeoffs and landings. I agree with budd that you quickly adapt to whatever you're using. Like him, I've flown a bunch of center (between your legs) sticks, side sticks, and yokes in either hand. I've even flown one he didn't mention--the Goodyear blimp uses pedals for directional control and a side wheel (2.5 to 3 feet in diameter) on the right side of your seat (sort of an over-grown trim wheel) for pitch control. Russ Erb +++ #7112 Date: Fri, 10 Aug 2001 21:30:44 -0500 From: Tim Hickey tjhickey@ Subject: RE: Stick Position Hello, Group It is a little early for me to get involved in much discussion about Bearhawks, as at best it will be two years before I have a chance to start such a project. However, I do have a Zenith CH-300 that I built from scratch, and have been flying now since 1987. (Well, not flying all of the time. I do have about 1200 hours on the machine now :-) ) About the stick position. The CH-300 was designed with a center (between the pilot and the passenger) stick location. I designed my own system to place the stick between the knees. This really is a much more natural feeling than a central location. My friends with Zeniths say that they wish that they had done something similar. One thing that I did that I have used occasionally is that I made the passenger stick removable. I just welded a large bolt on the upper piece, and welded in a rounded off nut in the lower piece, and then if desired you can just unscrew the stick and put it in the back out of the passengers way. Just someting to consider. I will be reading this group, but not posting much because I have a house to build. I just retired from the Dial Corporation, and now I am going to let the carpenter in me run free. For at least two years, or maybe a little more.. Then I can get into building another, bigger, plane. The Zenith has been a great machine, but it is a little small, and as they say, bigger is better. I will be very interested in how the machines being built by the group members fly. Good Luck to everyone. +++ #7113 Date: Fri, 10 Aug 2001 19:22:39 -0700 (PDT) From: Jimmy Mathis tallow_98@ Subject: Re: Stick Position I second that idea. I think it would be more comfortable on the right. Last year at oshkosh I sat in a few planes that had the stick between my legs and I really didn't care for that. Jimmy 501 +++ #7115 Date: Fri, 10 Aug 2001 21:47:02 -0500 From: Tim Hickey tjhickey@ Subject: Re: Stick Position I forgot to add one thing about the between the knees sitck position. If it is between the knees, on a long trip you can fly with the right had for awhile, and then use the left "for something new and completly different" Put it in the center, and you will be using the right hand all the time. And then... if you put the sitck in the center, you will then need to put the throttle and mixture controls on the left side of the panel. And if you want the passenger to have access to said controls, you will have to duplicate them on the right side of the panel. That is exactly what the CH-300 had in the plans. Put it between your legs. I think you will like that in the long run. Tim Hickey +++ #7117 Date: Fri, 10 Aug 2001 21:12:23 -0700 From: Budd Davisson buddairbum@ Subject: Re: stick position Put the stick in the center. Don't try to invent a wheel that's been invented a million times for nearly 100 years. If there was a better way, it would have won out long ago. Besides Curtis P. does this way and I know for a fact, none of us is smarter than he is. bd +++ #7122 From: charles.k.scott@d... Date: Sat Aug 11, 2001 1:02 pm Subject: Re: [Bearhawk] Digest Number 507 > Was wondering if anyone is trying any "different" stick > position(s) for their Bearhawk. I'm mounting my stick in the center of the fuselage. It will be configured such that the handle will fall into the right hand for the pilot in the left seat and the left hand for the person in the right seat. In both cases, the handle position will put the person gripping it with the hand over the thigh. For long trips, you can trim the airplane for hands off flying and leave your hands in your lap, if you wish. The one thing this does do, however, is make the throttle position problematic. If you mount it in the middle of the instrument panel, you'll have to remove your hand from the stick to reach it. The handle will be close enough to your left hand so that handing off won't be a problem but it's something to consider. A possible solution would be to have two throttles, one on the left cockpit side and one on the right. The Emeraude has such a system with the two throttles interconnected via a torque tube. No big problem, just more work to fabricate and install. You could leave the rest of the controls in the center of the instrument panel, but it would be nice to have your left hand on the throttle while your right is on the stick. Corky Scott +++ #7128 From: "Bruce A. Frank" Date: Sat Aug 11, 2001 4:58 pm Subject: Re: [Bearhawk] Digest Number 507 >A possible solution would be to have two throttles, one on the >left cockpit side and one on the right. The Emeraude has such >a system with the two throttles interconnected via a torque >tube. How about mounting the throttle on the stick using one of the lever type controls like those used to shift derailers on high end (expensive) bicycles. Bruce A. Frank +++ #7137 From: "Float-By Shooter" Date: Sat Aug 11, 2001 9:16 pm Subject: throttle on stick > How about mounting the throttle on the stick using one of the > lever type controls like those used to shift derailers on high > end (expensive) bicycles. This is actually fairly common on 4wd vehicles which are used for serious offroading. A bicycle shifter throttle mounted on the gearshift lever allows more precise control when climbing rocks and if you need to use the clutch for some reason, you don't have to juggle 3 pedals with 2 feet. The disadvantage is the added complexity. Particularly in the Bearhawk, the cable routing could be a nightmare, and would have to be done with great care so that changing the stick position would not cause the throttle setting to change. I doubt it would be worth the effort. Del Rawlins-- +++ #7144 From: "Bruce A. Frank" Date: Sat Aug 11, 2001 11:08 pm Subject: Re: [Bearhawk] throttle on stick It's a cable inside a spiral sheath. The lever holds in little tiny detents or excellent friction washers. Mount the lever so it protrudes out the top of the stick so you can use your thumb for adjustment and the cable runs out the bottom of the stick. The position set with the lever doesn't change when you go lock to lock with the handle bars on the bicycle, the stick is actually a less extreme environment. I have set up such a system on a go-cart with the lever out the top of the right hand grip on the cart's steering yoke. The cable ran through the arc of the yoke into and through the steering column all the way down it to the connect to the tie rods. It then looped around, back down the frame rail , under the seat and up to the carb. Then again, if the lever style is unsuitable, I saw a homebuilt 20 years ago that installed a smaller vernier push/pull type throttle cable in the top end of the stick. The builder replaced the round knob with a large diameter flat style button. This allowed the pilot, as he gripped the stick and to use his thumb to push the button up to reduce throttle and mash it down to advance the throttle. Since it was a vernier type he could spin it right or left with his thumb to incrementally increase or decrease the throttle. He even installed a wing nut style lock. The cable ran out the bottom of the stick, interfering with nothing, through the lower edge of the firewall and bolted to the bracket on the carb. I see this modification as straight forward and easily implemented with off the shelf parts. The gear change levers that stick in the open end of the handle bars on the bike worked perfectly for years on the go-cart. Then again I once made a amperage controller for my TIG machine that I held in my teeth and adjusted by biting or relaxing so I could more easily weld overhead stainless hydrogen lines while hanging from a seat sling. Putting a throttle on the stick seems to me a piece of cake. Bruce A. Frank +++ #7244 Date: Wed, 15 Aug 2001 15:37:40 -0700 From: Russ and Penny Erb erbman@ Subject: Cessna Trim Wheels The plans call for a Cessna trim wheel to be used for the trim system. Does anyone have the Cessna part number for the trim wheel so I can look up how much the certified highwaymen want for one? After I find that out, I'll decide if I want to use one or create my own. Russ Erb +++ #7245 Date: Wed, 15 Aug 2001 17:17:59 -0600 From: Brian Cox bcox@ Subject: RE: Cessna Trim Wheels > The plans call for a Cessna trim wheel I don't know how many variants there are, but I'll check my 310 MX/Parts manuals and supply a number for the trim wheel. Also, I recall that the Beech trim wheel in the Bonanza/Baron is similar in diameter, but is thicker. The ones I've seen are an off-white plastic and are silky smooth. Maybe one of these can be put in the overhead location on the Bearhawk? Brian Cox, #478 +++ #7246 Date: Wed, 15 Aug 2001 17:01:10 -0700 From: "Bruce A. Frank" bafrank@ Subject: Re: Cessna Trim Wheels >The plans call for a Cessna trim wheel What is the disadvantage of using the Piper jack screw style of trim? Bruce A. Frank +++ #7247 Date: Thu, 16 Aug 2001 00:10:16 -0000 From: t18cox@ Subject: Re: Cessna Trim Wheels Russ, There are several sizes of wheels. I don't have a parts manual, but looking in the shop manual I see the wheel is a part seperate from the shaft, sprocket, chain, etc. I picked up a complete assembly from Dallas Air Salvage for $5 or $10. You might check one of the salvage companies on the web. Bill Cox #303 +++ #7251 Date: Wed, 15 Aug 2001 20:22:21 -0700 From: Russ and Penny Erb erbman@ Subject: RE: Cessna Trim Wheels I'm not sure what you mean...if you mean a jack screw on the stabilizer, you could probably use one, but you'd have to redesign everything. The Bearhawk is currently set up for a trim tab and needs some sort of system to pull on two cables. Russ Erb +++ #7252 Date: Thu, 16 Aug 2001 01:24:42 EDT From: murrayhuff@ Subject: Cessna trim wheel Russ my 1968 C-150 has wheel assy tab control p/n 0460112-1 or 0460120-1. That of course is just the wheel,you will need a sprocket p/n 0432134-1 a chain -tab control p/n 0432138-8. Also you will need bearings to mount the sprocket p/n B45 and M451. And of course some sort of brackets to hold all of this. Look in the Junk Yard I am sure Bob did. murray huffines #506 +++ #7253 Date: Wed, 15 Aug 2001 22:27:28 -0700 From: "Bruce A. Frank" bafrank@ Subject: RE: Cessna Trim Wheels > I'm not sure what you mean...if you mean a jack screw on the > stabilizer, you could probably use one, but you'd have to > redesign everything. Some redesign or actually more in the line of a copy of the Piper jack screw system in place of the horizontal stab front tube mount position. Just the fact that it is a very low drag method of trim. Bruce A. Frank >>> 2mar02 #7686-9153 +++ #7861 From: "Bruce A. Frank" Subject: Flaps Actuation I had a friend visiting for several days last week. He helped work on my project while here. He has been a pilot since he was 16 with literally thousands of hours and over 1200 in a C172 0-360 constant speed prop STOL kit conversion. He looked at my overhead flap handle actuation system, pointed out some pros and cons then proceeded to make a strong case for electric actuation. Building such a system with the same style screw actuator I am using for my horizontal trim (jack screw-aftermarket part, 12 volt system) would actually simplify my construction. I have flown with him for dozens of hours and have seen no disadvantage to his electric flaps going into a lot of back country unimproved "SHORT" strips. I'd like to hear other's point of view about electric flap actuation. This may or may not be a safety of flight question as I will be running an auto conversion with a backup battery (isolated) providing power even in an engine out situation. -- Bruce A. Frank +++ #7864 From: Russ and Penny Erb Subject: RE: Flaps Actuation Assuming the flap actuation system is simple, I've always liked the rapid and precise motion of manual flaps. Electric flaps seem to always take 5-10 seconds to get in position, which might be a problem if I wanted them right now. Also when I think "electric flaps" I think of more things to fail (actuators, wiring, battery...). Russ Erb +++ #7865 From: "Bruce A. Frank" Subject: RE: Flaps Actuation Have you ever actually applied or retracted flaps intentionally in less than 3 to 5 seconds? I have done a few calculations with the mechanism I have and I could apply full flaps electrically, 0 to 45 degrees, in 3-4 seconds. Retraction would be equally fast if I wanted to dump them that quickly. In my limited flying, mostly Piper Tomahawks and Cessna 172s, flaps were always added and removed gently giving time to adjust attitude of the plane. Is there really performance I am giving up with electric activation? As for complication, A center off spring loaded rocker switch for extension/retraction, three wires to the motor (the motor/jack shaft drive is designed to handle 500 lbs of load) which is connected to a single tube running from one flap bell-crank to the other. Seems to actually reduce the number of failure points from my original idea of cable actuated flaps. Certainly virtually eliminates the likelihood of a split flap condition which, to me, is the only instantly life threatening situation. The other situations such as unextendable or unretractable flaps can usually be worked around. Keep speculating please. I want this thoroughly hashed out. Bruce A. Frank +++ #7866 From: Joel Mayhall Subject: RE: Flaps Actuation The technique for short field landings in a tail dragger that I was taught years ago was immediately on touch down dump all flaps to kill any lift and hard brake. Braking is ineffective if your still half floating with the flaps partially down. You travel quite a distance in 5 seconds at touchdown. Budd may have some better advice. - Joel +++ #7870 From: Ken Beanlands Subject: RE: Flaps Actuation If you plan to operate on floats you'll find manual actuation is great. I've used the rapid flap deployment technique to break a heavily loaded 180 off glassy water. We were moving along with 2 notches (20 degrees) and I just couldn't break the tension. A quick jab of the flaps to about 30 degrees and the plane popped right off. Another time is after touchdown especially if you are light and plan to step taxi to shore. Dumping the flaps quickly will plant you on the water and allow you to taxi in with no fear of becoming airborn. I have about 30 hours on a float equipped 172 and the one thing I complained about over the 180 was the lack of manual flaps. We got stuck twice having to land without flaps when a faulty voltage regulator kept popping off line (caused by overheating) and the battery drained. The first time we didn't notice the voltage dropping and the second time we were over open ocean and were in no position to shut off electrical equipment to save the battery. Fortunately, the 172 is light enough and has a slow enough stall speed that a lot of this didn't matter but had it been the 180, we would have been increasing the touchdown speed from about 55 to 65 mph. This is a speed where a lot of things can go wrong. If the electrical failed in the bush, you could be really stuck. A C-180 on floats WILL NOT take off without flaps. Your airplane might, but you may not get out of that tight little pond you landed in the night before. I've had too many electrical problems in various planes to trust a primary flight control (at least it's primary on floats) to electrical actuation. Ken Beanlands B.Eng (Aerospace) +++ #7872 From: "Bruce A. Frank" Subject: RE: Flaps Actuation You've almost convinced me! Bruce A. Frank +++ #7873 From: Ken Beanlands Subject: RE: Flaps Actuation OK, how about this: It looks so cool and manly to reach down and crank on the flaps ;-) BTw, most manual installations are lighter than manual as you don't need limit switches, position indicators, wiring, jack screws, and the motor. Of course, the Christavia MK 1 has it's own light weight way of handling the flap actuation that is garanteed not to fail....no flaps ;-) Ken Beanlands B.Eng (Aerospace) +++ #7874 From: Tim Hickey Subject: RE: Flaps Actuation > Is there really performance I am giving up with electric > activation? I want this thoroughly hashed out. It would certainly seem that a manual flap system would be more reliable from a dependability standpoint. Simple or more complex to design and build depends upon the airframe. My Zenith CH-300 has electrically operated flaps. The motor is an electric window operator from a large car GM product. The switch is a window up and down switch from the same model type. By selecting your attachment point on the driven gear element you can determine the amount of travel. The original Zenith design used a central attachment that result in a lot of people complaining that the flaps were too fast. You could go from full up to full down (25 degrees) ((Used to be 40, but that is another story)) in about one second, or maybe a little less.The complaint was that you had to be real careful if you wanted to get 1/2 flaps on extension, or if you wanted to "bleed off" the flaps on climb out. My flaps are much slower than the original design, but still rather quick. I would guess that it has about a 2-3 second travel time between up and down. The cost of the motor is cheap, all things considered. I think I paid about 20 bucks for the first one. I did have one fail. Motor just quit. I went back to the salvage yard and they gave me another one at no cost. The second one has worked fine for 5 or 7 years now. It failed in the full up position, but don't kid yourself, it could fail some day in the full down position as well. If working flaps are critical to your operation, then manual would seem to be the way to go. I suspect that an electrical installation might be a littler heavier, as well. I don't do much short field work, and often just ignore the flaps on takeoff and landings. Using flaps on the Zenith requires that you pay more attention to what you are doing. Good Luck. Tim Hickey +++ #7875 From: "Mike Carriere" Subject: Re: Flaps Actuation Frank: I transition between my C-206 (electric flaps) and C-185 (manual ) continuously and can honestly say "I like the electric better" I must admit all the arguments given against electric are at least partly true; but, over time you get spoiled and very comfortable with the electric flaps.- its a more civilized system eh! Test flew a new C-208 a couple of weeks ago- talk about civilized! +++ #7885 From: Budd Davisson Subject: Re: Flaps Actuation Re: Electric flaps electric flaps versus manual is an argument with no real answer as each has it's pros and cons. With all the high tech motors available, failure is a possibility but not a probability. I've only had electric flaps fail once in a life time of flying. personally, I like manual flaps on a short field because, as I'm in the final process of flairing, as the speed bleeds off and the airplane starts to settle, I can ease the flaps in with the handle and "plant" the airplane where I want it and have instant braking. You can do the same thing with electric, but you don't have the "feel" of the air pressure, so you can't change the rate of retraction to match the situation. It's a personal choice, I think. bd +++ #7886 From: Ken Beanlands Subject: RE: Flaps Actuation I guess that's what I like about the manual flaps. Retraction and extension can happen as quickly or as slow as you want it to. If you're heavy on a hot afternoon trying to claw your way up a hill after taking off from a lake, retracting the flaps over a 20 sec period is quite nice. If you've just landed and want to dump the flaps immediately, you can. You are not limited to just one rate. Ken Beanlands B.Eng (Aerospace) +++ #8436 From: Russ and Penny Erb Subject: Trim system gearing Here is a request for primarily for Mike Meador, but anyone with access to a flying Bearhawk can answer: Mike once told me at Sun'n Fun or Oshkosh that on the prototype they normally only have to move the trim wheel over a range of about 1/4 to 1/2 turn for any flight condition. I'm thinking that I would like more turns to my wheel, similar to a Cessna that takes multiple turns to trim throughout the speed range. In order to set up this gearing, I need one critical piece of information: Mike, would you please measure the amount of deflection of the trim tab (not the wheel) from the max up trim to the max down trim position and report back to us? Either the degrees of movement or the inches of travel at a specified point on the trailing edge would be fine. Thanx, Russ Erb +++ #8439 From: Budd Davisson Subject: Re: Trim system gearing The "sensitivity" of the trim wheel isn't a problem at all and I'm not sure it's worth the effort to change it. In fact, until you just mentioned it, I didn't even remember it being ratioed that way. bd +++ #8440 From: Russ and Penny Erb Subject: RE: Trim system gearing I didn't mean to imply it was a problem--this is merely a preference. I fly a bunch of gliders where you move the trim knob about 1/16" to make a difference. I have no problem flying them, but I prefer it to be less sensitive. Russ Erb +++ #8499 From: Russ and Penny Erb Subject: Trim system measurements > I'm holding some purchase decisions awaiting your answer. From: Mike [SMTP:mike2799@r...] Subject: Re: Any progress on those trim system measurements? I gave the question to Bob and he said that Max 5 degrees up or down is all that we have ever used in both aircraft. The swing of the trim wheel is about 2.5 - 3" for 5 degrees. The total swing available is 10 degrees up and down at the flap and that is 180 degree turn at the wheel - you could get more with a longer chain on the sprocket of the style that we use. Bob said to tell you that the trim tabs are very powerful and he would not add more travel to the trim than 10 degrees. I hope this helps - If I didn't answer the right question let me know. Later - Mike +++ #8564 From: "cbcflying" Subject: Trim question I'm currently working on the tail of my experimental Pacer project. I'm going to change it to a system very similiar to the BH using trim tabs instead of adjusting the stab incidence for pitch trim. I'd like to hear some pros and cons for using a vernier for elev trim instead of an overhead wheel. I'm thinking dash mounted. A con I can think of would be the lack of a real indicating system showing exactly where its set. I think this could be overcome with the eyeball and then adjusted in flight though. A pro is the simplicity of installiing it. Obviously it would have to be rigid enough to prevent flutter. I know one fellow who used a vernier for trim on a home built and said it worked fine. Thanks, Brian Cantrell #511 (for sale) +++ #8566 From: Brian Cantrell Subject: Re: Re: Trim question > My question would be why are you changing the trim system? In > general I would think the moving stab is more powerful than > using a trim tab. Thanks for the reply. The reason I'm interested in changing from the original Piper trim system is twofold. First of all, the Piper system uses one continuous cable that runs from the trim crank pulley back to the jackscrew on the stab. That cable is kept taut by two idler pulleys under spring tension. It doesn't use any kind of chain or sprocket like the BH and Cessnas. From what I've heard and read, (I've only flown military planes with electric trim so far - except the T-34C) the Piper system is prone to wear and slippage after time. It's not adjustable and therefore, it doesn't always give very positive trim control. Second of all, the Piper continuous cable is very expensive and because my fuselage is a foot longer than the Pacers and Tri-pacers, I would have to have one custom made. It just seems to me that using a more conventional trim tab system would be more affordable, simple, and reliable. I'm definitely open to suggestions from the field though. Thanks, Brian +++ #8567 From: "Bruce A. Frank" Subject: Re: Re: Trim question The original cable system is easy enough to adapt. Alan Williams in Florida built a V-6 STOL. He kept the original trim handle in the same spot in the overhead, but created another pulley location further back in the overhead connecting the two with a fine chain sprocket. This allowed him to use the original cable. If you wanted to keep the same arrangement at the original Piper setup it is easily worked around. Roger Lehnert, the national rep for Randolph Coatings, who has rebuilt several J-3 Cubs, was a hangar mate when I lived in PA. Rather than going to the expense of buying or having fabricated the continuous loop cables for the trim he'd just splice regular small diameter cable with the usual crimped lug system use on all the rest of the cable runs on the plane. With the trim adjustment set in the middle of range he'd install the cable with the splice half way between the pulleys. He told me that this never ran the splice point into the pulleys and gave full trim adjustment. Bruce A. Frank +++ #8568 From: pfflyerz@c...> Subject: Re: Re: Trim question I've have a lot of hours in a couple of Super Cubs and I can only comment on how they operated, but I never cared for the Piper jack screw system. You couldn't trim these cubs by setting your attitude and trimming out the stick force. You had to relax pressure on the stick while turning the screw. Since I was glider towing and always going either up or down I never bothered with the trim and just used the armstrong method. The Bellanca Scout trim is a joy to use and I hope the system I am incorporating will work the same way. Pat Fagan #232 Pearblossom, CA +++ #8569 From: Ken Beanlands Subject: Re: Re: Trim question If the Scout is like the Citabria, then this is also the system I've gone for on the Christavia. A simple lever mounted under the throttle that you push forward for down trim and back for up. No fuss, no muss. I actually got to hate the PA-18 trim. It seemed to be a similar setup, but the lever was much further down and rearward making it very difficult to operate. Ken Beanlands B.Eng (Aerospace) +++ #8853 From: "rodsmith52" Subject: Re: Bearhawk Pireps Thanks for the report Wil, sounds like there were no surprises in performance or handling. On Proto II with full forward stick the stick was directly under the 3/4" cross tube at the bottom of the instrument panel with only about a 1/2" vertical clearance. Did you modify your control sticks? Rod Smith #246 >>> 4sep02 #9154-11297 +++ #10384 From: Russ and Penny Erb Subject: Hey, what happened to the finger gussets? Pull out Drawing #27 (rudder pedals). Note that there are .050 finger gussets shown at the bottom of the left side rudder pedals but not on the right side pedals. What gives? Do the left pedals need the gusset because they have the brake installation? If I put brakes on both side then do I need gussets on both sides? +++ #10390 From: "Dan Montee" Subject: Re: Hey, what happened to the finger gussets? My assumption was that the gusset was needed for the brakes. I put gussets on both sides. I don't know if I will use brakes on both sides to start with but I wanted the option. +++ #10391 From: "lbhensley" Subject: Re: Hey, what happened to the finger gussets? Russ, If you have the chance, look at the Big Rebel with the Russian radial engine on it. Look at the pedal set-up. I adapted the brake pedal portion to my pedals. Although on mine, I have the ability to completely dismantal and rebush the pedals, I still used the inside/outside design that Bob had originally built. My pedals are easy to build and easy to maintain. If you would like to see a drawing on this particular change, feel free to e-mail me at lbhensley@a... +++ #10395 From: Russ and Penny Erb Subject: This, budd, 's for you... You may recall a while back that Pat Fagan said he had just finished machine turning his instrument panel. budd got all excited and wanted to see a picture. Well, now's your chance. Go to the Yahoo Groups Bearhawk site and check out the new photo album titled "Fagan Panel and Trim". Besides the panel, you will also see photos of Pat's trim system. Pat decided to use a lever trim system instead of a wheel. While looking at the trim system you will also see how Pat set up his skylight. I was down at Pat's today using his lathe. Everything on his Bearhawk is covered and he is finishing up the Poly Spray. Looking better each day! +++ #10727 From: Russ and Penny Erb Subject: Supporting Relocated Brake Cylinders Through extensive anthropometric analysis (i.e. had a bunch of EAA Chapter members come over and sat in the seat), I have 99% decided to move the rudder pedals toward the seat. On the plans, the rudder pedal axis is about 4.5" aft of the firewall. According to one Bear-Tracks, the rudder pedal axis in Proto II is 5" aft of the firewall. Based on my analysis and testing, the best location is a rudder pedal axis 8" aft of the firewall. Therefore, I assume the mounts for the brake cylinders should move aft an equal amount. However, this leads to a problem (imagine that!). The plans show the brake cylinders supported by .063 tabs welded to the lower T11 tube at Station A. If these tabs, which are roughly 1" long, are extended by the required 3.5" to 4.5" long, I'm afraid that they will twist and fail when I honk down hard on the brakes. The first solution that comes to my mind is to weld in another crossmember 3.5" aft of Station A, and weld on the support tabs as originally designed. Since this tube would only be supporting torsion loads from the brake cylinders, does it need to be T11 (3/4x.049) or would T10 (3/4x.035) do? Another idea that just occurred to me is a U-cross section bracket (similar to the brackets that hold the control stick bearings) with the cylinder attached to the sides of the bracket rather than the top. The inner brackets would still connect to the firewall tube, but the outer brackets would have to connect to the diagonal tube between Station A and the center of Station B. Now soliciting your opinions on these ideas or any alternative ideas you may have... +++ #10728 From: Budd Davisson Subject: Re: Supporting Relocated Brake Cylinders A. Check the stick-forward position for clearance. B. In flying the airplane I never noticed them being too far forward. C. is there a possibility you have munchkin legs? +++ #10729 From: Russ and Penny Erb Subject: RE: Supporting Relocated Brake Cylinders Spoken like an average or taller than average person! Reviewing the pictures and my memory, I would not expect you, or the Arizona Redhead, to have any trouble reaching the pedals. I, too, was able to reach the pedals in Proto I at the expense of sliding the seat very far forward. This also put me much closer to the instrument panel than I cared to be. To wit, pulling the throttle to idle should not cause interference between my elbow and the seat. According to Air Force measurements, my leg length is 42.5 inches (sit in a chair and measure from the back of your butt (the chair back) to the bottom of your heel). The same measurement is 38.9 inches for a 5th percentile male, and 46.1 inches for a 95th percentile male. The important dimension here is that my leg is 3.6 inches longer than the 5th percentile male. By studying the plans, I determined the control stick position for full up elevator. This set the most forward position of the seat. Moving the seat aft 3.6 inches, I sat in the seat and adjusted the rudder pedal position until it was comfortable for me. As an added benefit, the instrument panel was now a convenient distance away. My wife is something like 5' 4" tall (I'm 5' 9" tall). I put her in the seat. With the seat all of the way forward, she had full throw on the rudder pedals and an easy reach to the instrument panel. Another pilot friend who is slightly shorter couldn't quite get full forward stick or full rudder deflection. However, he still had about 2 inches between his stomach and full aft stick. We figure with a 2" cushion behind him, he'll have full stick throw and full rudder throw. He wouldn't have a chance in the Prototypes. You might say that this will result in my eyeballs being farther back on the ground with the resulting reduction in visibility over the nose. My response is I can still move the seat forward and bend my knees more if required. One problem with many homebuilts, such as RVs and Glasairs, is that each builder must adjust the control and seat positions to fit him/herself. This causes at least two problems: 1. When your friends fly with you, they run the risk of either not fitting comfortably (too tall) or of not being able to fully control the airplane (too short). (I've never cared for the cushion/pillow/phone book seat adjustment method, even though that's what we do in the gliders) 2. If you decide to sell the airplane, chances are the buyer will have the same problems. My goal is that the maximum number of people (including those shorter than me) will be able to find a seat position that works for them in my airplane. This is more than I can say for some production aircraft I've seen. I don't understand your question about stick forward clearance. There is still at least 10 inches between the stick and the pedals. Munchkin legs indeed. I was rejected from the Lollipop Guild for being too tall. Now, howzabout an answer to the original questions? +++ #10733 From: shell "Shelly" Subject: Re: Supporting Relocated Brake Cylinders Russ, have you worked the effect that height into your equation? I have found that by adding or subtracting the thickness and density of the seat cushion enables several very differently built pilots reach a comfort zone. (Be careful - you might need to wear a hardhat!) +++ #10735 From: Russ and Penny Erb Subject: RE: Supporting Relocated Brake Cylinders All of the tests were done on the Temperfoam cushions that will be installed. Remember the seat rises as it comes forward, which does seem to help. +++ #10736 From: "Vuxton, Christopher G Mr SAALT" Subject: RE: Supporting Relocated Brake Cylinders I was just around the corner a few months back to look over a Kit Fox that was ready to slip the surly bonds of the garage floor and move to airport. The owner was very proud of the adjustable rudder pedals. Seems the thing has two levers in the center console (no such item in ours but come on, soembody could design something around this) to adjust the pedals forward and back. This was a brand new 'fox and I'm not sure of the model. Has anybody seen this setup? What do you think. +++ #10903 From: Budd Davisson Subject: rudder balance/trim/engines Additionally, I was thinking about decreasing the elevator trim to > maybe one instead of two. Everyone has said now little trim is needed > to normal operations. Would both be needed with a "load" in the back > seats? How about eliminating the trim tabs, and going to a spring > trim system? (bet I get some comments about being an aircraft designer > on this one) :-) Re: trim stuff Bob mentioned something to me the other day that I haven't had chance to track down: he said the Glasairs use a worm drive trim that is ratioed down to what's really needed for the airplane. The problem now (it's not really a problem, just something to discuss) is that the trim wheel only moves about 45 degrees for full travel. Maybe less. The ratioed system would give more turns. The lever system I believe Pat is using could be made to do the same thing. +++ #10905 From: Russ and Penny Erb Subject: RE: Re: OK Enough of the teasing. What did you buy? > Additionally, I was thinking about decreasing the elevator trim to > maybe one instead of two. My solution was to increase the mechanical advantage of the trim system--i.e. more turns of the wheel for the same tab deflection. As for spring trim, sure, it could be done, but I've yet to find a spring trim system that I really liked. They always seem to run out of down force in cruise. Also remember that a downspring will increase your stick force gradient, so you'll have to pull or push harder on the elevator control. +++ #10908 From: "drycreek201" "Dave" Subject: trim On the subject of trim, has anybody ever looked at the trim control on a t-craft. The crank sets in the same place as the BH, except it is horizontal. It is about two and a half to three turns, take off to cruise. I plan on taking the cover off of mine some day and seeing how it works and if it would work in the BH. It has to be simple because it was built in 46 and it still works like it is suppose to. Just an idea and I think the hump would be gone if I put a skylight in. +++ #10910 From: Budd Davisson Subject: Re: trim > On the subject of trim, has anybody ever looked at the trim control on > a t-craft. Dave has a good point, although I've always hated trim cranks, they would work well here. Russ, I'd like to hear more about your ratioed trim wheel. A lever set up with a knob-in-a-gate like an old Champ would be an easy conversion too. >>> 20may03 #11298-18250 +++ #13563 From: "Russ Kaye" Subject: Piggot Project I don't mean to offend anyone here because for the most part that looks like a real fine project and I'm sure it's just personal preference but that flap handle location would worry me. Russ +++ #13564 From: Russ and Penny Erb Subject: RE: Piggot Project And why would it worry you? Russ Erb +++ #13566 From: "conohawk" Subject: Re: Piggot Project I was a little concerned about that myself. As someone who has flipped a plane during the landing sequence (axle failure on my old, late, Cessna 140) , I would prefer not having a long shaft of steel pointing down from the ceiling, shoulder belts or not. It could be that Jack Piggot and Dan Donovan (the builders of the aircraft in question) have determined that no safety issue exists. I didn't sit in the cockpit (since it was getting taped in preparation for paint. -Mark Conover, #502 +++ #13596 From: Ken Beanlands Subject: Re: [Bearhawk] Re: Piggot Project It's not just the "flipping" piece I'd worry about. I found the flap handle in the Rebel to be rather annoying as I thumped my head into the thing twice (granted, I do have a big head, but still...); once on a rather bumpy final approach and once while gettin in the plane with the flaps extended. Ken Beanlands B.Eng (Aerospace) +++ #15740 From: Pat Fagan Subject: recommendations First off, you should absolutely make the modification to the flap quadrant that is mentioned in one of the Beartracks (don't rememer which one). The flap is quite a reach, especially if you have to push the button to operate. Modify the bottom notch on the flap quadrant so that you can pull on one notch of flaps without having to press the button. This makes the flaps much easier and safer to operate. It isn't neccesary to add the grab handle as also mentioned in Beartracks. ... Pat Fagan #232 Pearblossom, CA +++ #15781 From: Budd Davisson Subject: Re: Electric Flaps (was Re: flaps) Long ago I developed a habit, when working a short field. of slowly bleeding the flaps off as I flared the airplane timing the loss of lift to coincide with the change of angle so I could plant it right where I wanted it and have no reserve lift after touchdown. This gives maximum braking right off the bat. This doesn't work well with electric flaps. With mechanical flaps you feel the load on the handle and, as the airplane slows and the pressure on the handle goes away, you can "ride the pressure" down with the handle and know exactly how much flap you can afford to give away and when. This isn't as dangerous as it sounds, but I don't recommend it to low time pilots or those who aren't in tune with control pressures. bd +++ #17482 From: "Dan Montee" Subject: Re: Re: Trim Wheel > I'm looking for a 5" diameter trim wheel (with a small sprocket > attatched) to mount in the ceiling of the BH. Try Summit Aviation, 816-224-4900. Dan Montee +++ #17485 From: "t18cox" Subject: Re: Trim Wheel Try Dallas Air Salvage. WWW/ASOD.com I got the wheel with sprocket and chain for a few dollars. Bill Cox +++ $Id: 2.3.3-Fuse-Controls,v 1.11 2003/05/22 03:23:13 bentonh Exp $