Q-talk 11 - QUICKIE-TIPS
- Category: Q-Talk Articles
- Published: Wednesday, 31 August 1988 07:11
- Written by Jim Masal
- Hits: 2154
From Norm Howell, Spangdahlem, GERMANY
A quick update on my Quickie. On the way home from Oshkosh my Rotax didn't seem to develop as much power and would not climb up "on the pipe" until after 85-90 mph when the prop unloaded (ED. NOTE: Norm told me previously that when the throttle is advanced, there is a point where the engine hits its power band and a distinct boost in acceleration is felt. He calls it getting "on the pipe"). This power drop made for Onan-style takeoffs. The problem got worse by the time I got home to Oklahoma. I figured it was the timing so I retimed per the Rotax video. No change. I suspected crankcase FOD (foreign object damage, USAF jet term - ED.) from an unrelated problem, so I sent the engine to LEAF for teardown inspection. They said the timing was advanced. I couldn't believe it but I finally figured it out.
The Rotax is timed by measuring the distance from the TDC of the piston when the points break. This is done with a dial indicator stuck into the sparkplug hole. On my engine there was quite a buildup of lead and carbon on the piston, which gave a false indication of piston travel (I had been using 100LL). This caused me to advance the timing too far. The engine will be reinstalled soon and I'll let you know the results.
Bottom line - the Rotax is dandy for the Quickie. However, I highly recommend the Rotax video from LEAF and the tools required to do the timing from the LEAF catalog. The Rotax engine should be timed after 15 hours. The cam rubber block will wear out fast when the engine is new and you cannot verify this by much before the power begins to fall off. I timed it at 27 hours and that was definitely too late.
(ED. NOTE: In a separate note, Norm sent a copy of a letter from the National Aeronautic Association congratulating him for his latest 2 record attempts which were approved as US National Records and were forwarded to Paris for registration as World Class Records. His record speed over a 15/25 km course was 146.19 mph and his record time to climb of 3,000 meters (about 9,000') was 18 minutes, 5 seconds.)
From Ted Kibiuk, Holland Patent, NY
My black beauty is ready for preliminary taxi-testing Sunday 10/2/88. The hayfield out back is cut and ready to use. I expect to put on 5-10 hours at slow speeds to break in the engine and feel it out before the snows set in. Then I'll bring it back in the shop for final tune up and Imron yellow paint to be ready for a spring flight. The project has come out better than expected - it looks elegant!
Besides myself, I know that Lanny Rundell, LA and Bob McFarland, PA had the Quickie LS-1 plans. Hopefully both my wings are set correctly for a smooth liftoff. I have the large wheels and had to design larger wheel pants with the assistance of Terry Crouch.
(ED. NOTE: Sheehan told me at Oshkosh that he thought 15 or 16 sets of carbon spars for the Quickie had been shipped before the business closed.)
From Gene Comer
I've been working on the Quickie LS-1 canard for some time. This is slow going due to the poorly set-up construction plans. Once you've gone through the mental effort to avoid all the negative things that might happen during the next phase of construction and then something happens anyway, you go into severe depression. That's my best reaction to the "Plans" (???) for the Quickie LS-1. The Rotax 447 Quickies of both Ed Miller and Gerry Wardell are within easy driving distance for me. Gerry's is 10 miles away and I'll get pictures of his installation for you. Gerry did some very careful reworking of the muffler assembly and was able to contain the whole installation within his very smooth cowl. Gerry has an air scoop on the left side of the cowling over the single carburetor and this could be eliminated with a dual carb system.
ED. NOTE: Someone ought to form a QBA "section" for all you Quickie LS-1 builders and exchange names, addresses and phone numbers. All you guys seem to be struggling with plans that are not for poop!
I suppose the Rotax 447 is somewhat physically similar to the Rotax 503. Anyway, QBA's pet record-buster, Norm Howell installed a 503 with more records in mind and he decided to install a single carb for better fuel economy and less complexity. When he saw the size of the cowl bump needed and the drag possibilities, he went back to duals. He has a beautifully smooth cowl but still faces a problem of finding room enough for carb filters.
What I would like to know, bump or not, is whether the single carb fuel efficiency is REALLY much better. Maybe the drag penalty of the scoop is worth the fuel savings. Gene, please keep tabs on Wardell's experience with fuel consumption and top speed for us.
From Dave Barth, Denver, Colorado
After reading Norm Howell's interesting and humorous article about his Quickie in "Sport Aviation", in the Fall of '87, I bought a Quickie that had been repaired following a landing in a soft field. After I had purchased and read all the back issues of "Q-Talk", I realized that the Onan was not going to be my engine of choice here in the Denver area where high density altitudes are common.
Also, I wasn't impressed by the Onan's multitude of problems pointed out by "Q-Talk" contributors. They included stretched head bolts, severe vibration, high engine noise, critical battery voltage, overheating tendencies, loss of power, extremely high maintenance requirements, high wear rates and general unreliability.
As a result, I never even started up the Onan on my Quickie. I pulled it off and put it up for sale. At the same time I began an engine search. I was looking for the mythical 50 lb., 30 HP, four-stroke, smooth, quiet, fuel-efficient, low-maintenance engine. I was interested in "Q-Talk's" discussions of two-stroke engines, but I wasn't enthusiastic about running a "Ring-A-Ding-Ding snowmobile engine on the Quickie.
Then I ran across Ed Miller's "Trade-A-Plane" ad to sell his Rotax 447-powered Quickie. I talked to Ed and got a hold of his report on how he converted to the Rotax. Through "Q-Talk" I read about Brock McCaman and Jinx Hawks' Rotax 503 Quickies in California, and I sent for their report.
Finally, convinced that there were some definite advantages to two-stroke engines, I ordered a Rotax 503 with the single carb (keep it simple), muffler and 2:1 reduction drive from LEAF, Inc. of Colorado Springs, CO (719-632-4959).
From this point, I couldn't have gone forward without the great help from several members of the EAA 660 club in the Denver area, the same club that had assisted Norm Howell at one time. I have to confess that I am not much of a builder, and the project would have stalled many times without their kind advice and, often, outright assistance.
The engine mount was the first big challenge, and it was built similar to Ed Miller's design. There was a lot of work to prepare the firewall and rerun the cables and wires.
A beautiful, two-bladed, 48" diameter, 44" pitch prop was obtained from GSC Systems, Ltd. (604-549-3772) in British Columbia for a reasonable price. I ordered the cowling and spinner from Composite Aircraft Components (CAC) (901-586-4311), also from a reasonable price.
The cowling was produced by CAC from Ed Miller's Rotax 447 cowling design, so it required the addition of cheek bulges on each side of the 503 to accommodate the carb on the left and the exhaust pipe on the right. (A more elegant solution has been engineered by Norm Howell where he has no drag-producing bulges, whatsoever!)
A section of the top of the cowling was raised an inch to accommodate the plugs, and the front of it was cut open below the prop shaft to provide better cooling to the lower part of the engine and carburetor intake. No changes were required on the bottom where the large muffler is fitted. I spent $50 for Dzus fasteners to make it easier to get the cowling on and off.
The engine itself was left entirely stock (keep it simple). The pull starter handle was routed through the firewall to allow starting the engine from the cockpit. Starting the engine from the cockpit is a most convenient feature.
My calculations suggested that the extra weight of the engine would require an 8 lb. weight added to the tail cone. However, flight-testing indicated that only two pounds were required. That experience showed me that homebuilt characteristics can vary widely within type, as pointed out in "Q-Talk".
At this point, a gallon of auto gas was poured into the Quickie tank and the engine was test run. It fired up easily, and has been easy to start, relatively quiet, smooth-running, and trouble-free.
Then "BIG TROUBLE" hit. The gas tank began leaking. After five tries to fix it, including cutting out the bottom and top of the tank, building a new bottom, re-glassing the inside walls, putting it all together again, and sloshing it, it still leaked, so I gave up. I bought some 22 gauge sheet steel and a fellow club member welded up a 7 gallon tank weighing 8 lbs. that fit in the open cavity of the original glass tank.
When I cut the top of the glass tank out, I left an inch lip on each side to help maintain some of the structural support. The tank is only 14.5 inches wide; so one of the benefits is left and right side pockets between the fuselage and the tank for storing charts and other flat objects. The tank can be disconnected, and easily lifted out (but it is heavy if full of fuel when you decide to pull it).
It is slightly deeper and longer than the original. Were I to do it again, I would seriously consider using aluminum. I doubt there would be much of a weight saving because thicker gauge would have to be used, but it wouldn't rust, and the thicker plate would have less tendency to "oil-can".
I sloshed the tank to help inhibit corrosion. The filler is positioned inside the cockpit, between the knees, and consists of a filler neck off a pickup truck.
I thought a lot about what kind of fuel gauge to use. An external sight or float gauge was impractical because the tank was too narrow. My legs cover the tank except for the filler, and that area must be kept clear for use of the brake and starter cables. I didn't want to use an electric gauge (keep it simple).
Then a club member suggested I check the local boat dealers for mechanical pointer gauges built into a filler cap. Sure enough, there is a readily-available gas cap with a float mechanism that extends down into the tank and registers fuel level on a gauge in the cap.
As usual, it wasn't a simple matter to switch caps. I had to disassemble the truck gas cap and epoxy various parts onto the modified boat filler cap so it would fit the filler neck.
Additional things that were done to the Quickie included replacing the thin-walled aluminum axles with 4130 tube having a .159 wall (good grief, they would probably support a 747). 3/4 inch holes were drilled in the outside of the wheel pants for filling the tires, and they were capped with white plastic covers from the hardware store.
The brakes are atrocious! Jinx Hawks, who built one of the first Rotax 503 powered Quickies, said he doesn't use them - he has learned to plan ahead. For me it is a real heart-stopper to be rolling toward an intersection and suddenly realize that if someone crosses in front, you can't stop, and the grass is the only place to go.
In the early taxi tests, I would suddenly find myself coasting to an intersection without brakes (practically speaking), grabbing the brake handle (which conveniently rests over the fuel filler neck) and pulling like hell. I soon realized that I was fighting the idle thrust of the Rotax, so it helps to kill the engine to slow down, then easily restart it from the comfort and safety of the cockpit.
In an Onan-equipped ship, this could be a problem (especially on a runway) requiring the pilot to drag the plane off the taxiway or runway to clear it for other traffic and prop-start it. With the Rotax, I simply flip the ignition (mag) switch back on and give one pull of the starter cord.
As for the fabled "Ring-A-Ding-Ding" of a two-stroke, from the cockpit, this engine actually sounds like a turbine. In fact, the Walter Mitty in me likes to modulate the throttle slowly to emulate the sound of a King Air spooling up. (A little imagination helps, too, as I'm sure, King Air driver, Jim Masal, will attest).
Starting the engine when it is cold requires use of the choke. A remote choke control cable has been installed on the panel. For hot starts, don't use the choke. Pretty simple.
Since the engine comes from the factory (in Austria) set up for sea level, I changed the high-speed jet from 180 to 172, as per LEAF's guidelines, to run a leaner mixture. I also repositioned the carb needle for the same reason.
I have not installed carb heat, and the engine has no mixture control. It uses points and condenser type of ignition, which is old-technology, but possibly more reliable. Also, oil must be added to the fuel, which is a pain, but at least it makes for less complexity under the cowl. State-of-the-art engines use an oil injection system, but the trick is not to run out of oil before you run out of fuel.
The static RPM for my 503 at density altitudes around 7000 feet on a warm summer day are 5200 to 5400. In flight, at max cruise, I get 6000, just below the 6250 redline, so the prop is probably pitched a bit too much. At max cruise, I true out at around 140 MPH. Definitely a hot little shop!
Here are the plusses and minuses, comparing the Rotax to the Onan, as I see it:
FOR THE ROTAX
1. Simple - very few moving parts (no valves).
2. Easy to start - four pulls when cold, one pull when hot.
3. Quiet-Running - (The big muffler really helps.) By the way, Norm Howell explained to me how critical it is to use a stock exhaust system. Apparently, the shock wave reflected from a plate in the muffler back to the exhaust port helps trap the fuel/air mixture in the cylinder as the piston rises for the next stroke. The length of the exhaust pipe has a variance of plus or minus 1/8 inch.
4. Smooth-Running - (a little vibration at slow idle).
5. Reliable (so far).
6. Uses a mag, so the battery can go dead and you still have the engine (unlike the Onan which will die without warning when the battery reaches 25% charge).
7. Starts from inside the cockpit. This makes it much more fun to start in front of a crowd, when alone at the airport, or in flight.
8. 46 HP from a 90 lb. engine.
9. A friend of mine who has used Skidoo snowmobiles for years says he can give a Rotax a complete overhaul in an afternoon for less than $200 in parts. (That beats the overhaul cost of a lot of aircraft engines!)
AGAINST THE ROTAX:
1. High fuel consumption. Depending on RPM, anywhere from 2.8 GPH at economy cruise to 6.5 GPH at max RPM (6250 redline).
2. Two-stroke engines are sometimes not taken seriously. (QAC should have chosen one for the Quickie, and the Onans should have been left on the ground to run generators and pumps.)
3. Requires a gear reduction unit.
Being cold-blooded, and appreciative of the heaters that spam cans have, I designed and built a cabin heater based on the design of the carb heat muffler on the Onan. It is made of a sheet of stainless that forms a hollow tube about 4 inches long and 4 inches in diameter when fitted around the exhaust pipe. I built a flapper box to switch the hot air flow from going into the cowling outlet or the cabin. It has been too warm (especially this summer!) to see how well it heats the cabin.
I saw how another friend built a simple aileron reflexor for his Dragonfly, so I built one for the Quickie. I test flew it, and it works like a charm. I suspect that a little care must be taken during design and installation to ensure that it won't kill so much lift on the main wing as to cause it to stall before the canard.
It may allow a bit more flexibility in regard to C.G., but I'd be mighty careful. One drawback I discovered when I landed at 80 MPH is that I could operate the reflexor to drop the tail to a landing attitude, then kill lift on the canard with up elevator, and set the plane down at too high a speed. A spam can won't land at speeds like that, but will wheelbarrow on the nose wheel.
I have over 2000 hours, mostly teaching in Cessna 152s, and I have over 100 hours in taildraggers, mostly Citabrias. This Quickie handles differently from any other plane I've flown. It seems that the relative spacing between the mains and the tail wheel just isn't quite right.
My ego was bashed during the 80 MPH landing when I took my eyes off the runway centerline for a moment to grab for the brake cable. The plane began to drift to the left, so I applied a little rudder. Nothing happened. A little more rudder, a little more adrenaline. Still nothing. A lot more rudder, and then the plane was drifting toward the right row of runway lights.
Even with the large tail wheel, I wasn't able to reduce the pilot-induced-oscillation. Finally, at around 20 MPH, the plane did a 180 and skidded off the runway, between the lights. The wheel pant (for want of a better word) broke off due to the high side-loads imposed by the skid. Inspection showed that it had been constructed faithful to the plans, which call for two layers of glass. I beefed up the structure during repair. The lone (48 inch) prop clipped the dirt at the edge of the runway, but didn't break, and the engine wasn't dead-stopped.
The QAC literature considers a ground loop an acceptable, non-damaging maneuver to stop the plane if you run out of runway, and I suspect the plans are fine for lighter aircraft. However, mine weighs in at 332 lbs., empty, so the pants probably failed due to loads imposed beyond the design limits.
A Quickie, N77Q, is hanging in the Museum Of Flight at Boeing Field in Seattle, and some say that a museum is the best place for a Quickie. I say that builders will work the bugs out of the Quickie, and that we'll see more of them at Oshkosh in the future.
As for me, it is just too hot a ship. (Norm Howell has set several FAI-sanctioned records in his). It is a pilot's machine, and it requires well-honed flying skills. I prefer to putz round in a rag-wing. So, N86Q is up for sale. I will hate to part with it. It really has been a lot of fun.
I sure appreciate the information that Q-Talk (and the contributors) have provided. This is a tiny repayment toward that debt.
Someone wrote recently wondering if anyone had tried inboard gear on a Quickie. Ed Chalmers radar must've started buzzing because he's tried it and here's his report just when I needed it. Thanks Ed. Also, Ed made the news in a clipping he sent showing his forced landing in a Ramona, CA cow pasture. Readers will recall pictures of Ed's inboard-geared Quickie published in previous issues.
During last Dec. and early Jan. '88, I took N43EC to Ramona for some preliminary high speed taxi tests and short runway hops. Taxi tests at speeds over 45 mph quickly convinced me that reverse aileron steering was superior to tailwheel steering with far less danger of over-control and pilot induced "S" curve oscillations and/or ground loops.
With this bit of favorable experience under my hat, I proceeded to make a series of exploratory partial power runway hops. In the course of one of these hops I decided to try out full aileron reflex action. I suddenly found myself too high to land safely on the runway and decided to make a go-around. I applied full power but I got stuck at 50-75 ft. AGL. More elevator produced more drag. It dawned on me that I now had an answer to a question that had bugged me for some time, to wit: "what built-in angle of incidence should the LS-1 airfoil canard have relative to the main wing?" It was obvious that I needed more.
I made a shallow left turn, flew a half mile then turned downwind. I saw hills at my eyeball level up ahead and rocky terrain all around so I decided to make an off-field landing in a small green valley just ahead rather than maybe not clearing the hills further in front. After a shallow approach, the tailwheel touched first, the mains rolled 30' then sand in the rain-soaked ground. The tail came up, shattered the prop then settled back. My shoulder harness was not tight enough so my head put a transverse crack in the canopy. I got out OK, made the local TV news that night and after an FAA debriefing my landing was classified as a "incident" rather than an accident (much to my relief).
In the intervening months I cut my LS canard loose and increased the incidence 2 degrees. I replaced the original gear with one that is wider between the wheels and lower for a closer fit to the 7 1/2-degree optimum. N43EC has a modified Onan with special cast heads and baffles, a 4-point engine mount and a kidney sump in place of the original cast sump.
While I have enjoyed the past 8 years of building and trying to fly 43EC, I've finally concluded as my 73rd birthday approaches that it's time for me to give up this project and head for a rocking chair. If any individual or group is interested in acquiring a project, assuming all risk and responsibility, I will give serious consideration to all requests and/or offers. Plans, QBA newsletters, trailer and an STS 720 radio are all available.
Edward D. Chalmers, 322 Magdalena Dr., Oceanside, CA 92056 (619) 439-3074
ED. NOTE: I was especially interested in more detailed info on the handling characteristics of this unusual gear configuration so I wrote and asked. Ed answered in this follow-up letter:
Regarding my experience with taxi tests of different landing gear configurations on the Quickie...I offer the following qualitative comments, sans quantitative data.
1. N43EC started out with small wing tip wheelpants as per original plans. I incorporated differential heel brakes from the very start. With these brakes and the lower ground angle of attack, I had no difficulty with high or low speed taxi performance. I had heard of reverse aileron steering, but I felt no need for using adverse yaw steering. I wondered what and why other Quickie builders were encountering in ground handling problems.
2. When I changed over to the LS-1 airfoil, I decided to increase my prop ground clearance by an inch or two so I modified my main gear to a more standard aircraft configuration. This made a significant increase in my ground angle of attack and made high-speed taxi rollouts a tough problem - especially with crosswind components. At this point I began to investigate reverse aileron steering as a necessity. Even with differential heel brakes, the rudder and tail wheel steering were not enough under high speed conditions.
3. Later on I installed a new inboard gear with prop clearance approximating the original small tip pant. I found that reverse aileron steering was not as effective at this ground angle.
In conclusion, directional control in all Quickie gear concepts should not be taken for granted. All Quickie jockeys should make it a point of getting familiar with reverse aileron steering. It could save a lot of expensive rebuilding, healing of wounded pride and maybe even pilot bodily impairment.
P.S. I did renew my private pilot license. Couldn't reconcile myself to a rocking chair. The offer to part with N43EC still stands, however.
From Blaine Word
I started construction of Quickie N53BW in the Springfield, MO area in 1979. A job change took me to Lebanon, MO where I completed construction. First flight occurred in March. '82. I followed the plans pretty closely and made no major changes. I did have a speed shop balance the Onan, however I couldn't tell a lot of difference in vibration level. I also changed to the Kevlar mount with ditto results. I briefly had the 22 hp heads but went back to the 18 hp heads - the performance increase of the 22 hp heads was hardly noticeable.
I am a low time 115 hr. pilot. Most of my flying was in C-150's and 172's. I did an extensive amount of taxiing before attempting first flight. I haven't flown tailwheel designs, but had little trouble transitioning to my Quickie. I found the adverse yaw from the ailerons during takeoff/landing rolls to be very useful in supplementing the rudder and learned to use it instinctively to keep the craft in hand during the landing rollout.
Flight-testing progressed with only one major complication: I had the right main tire go flat while I was flying! Don't ask me how; I can only surmise that a slow leak began during taxi/takeoff. At touchdown, the craft developed a definite swerve to the right that no amount of rudder or even magic aileron trick would correct. I switched off the Onan just before I scooted between 2 runway lights, down an embankment and into a blackberry patch! Damage appeared to be slight, however in subsequent days a seeping fuel leak began to appear on the exterior around the seatbelt bolts. Apparently the jarring ride into the boonies flexed the structure enough to cause the leak. This problem persisted despite twice opening the top of the tank and resealing with glass and epoxy. I ultimately removed the original tank, laid-up a new self-contained tank and installed it. Problem solved. N53BW now has 85 hours of flight time (50 by myself, 35 by my brother). I have gone through 4 props! Two succumbed during poorly executed landings and the other 2 through stupid ground handling mishaps. The cost of props became such a burden that I made the last one myself. It was a copy of the Cowley props and performed equal to them, which isn't saying much.
The performance of N53BW is the same as reported by other builders: 100 mph cruise and 250-400 ft/min estimated climb. It handles very well in the air, requires concentration on landing and is generally a fun airplane. You must be aware of its limitations (low power) and take care not to get into a situation where climb performance is critical.
I recently cut the fuselage in order to store the craft in my garage. I was greatly interested to learn of the Rotax conversions flying and am also interested in HAPI's Mini Mag 1/2 VW, but my re-entry into flying the Quickie is likely to be "on hold" as I have acquired a wife and 2 kids in the years since I began the project. Thanks for sending the '88 issues to Q-TALK, Boy are they ever a gold mine of info!
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