Q-talk 86 - Letters to the Editor
- Category: Q-Talk Articles
- Published: Wednesday, 23 December 2009 16:24
- Written by Dave Richardson
- Hits: 1550
Paul M Wright, Suffolk, England
During the life of my Ql, I have changed the panel 3 times (different engines have required that I lose the Oil Pressure and Temp for the Rotax 503). The final (Current) layout is hard aluminium (aluminum?) which was taken from the tailgate of a scrapped Land Rover and crackle-baked in black for a fiver. I went to small instruments so that I could get them all in the 22" cockpit of the Ql. I had to re-position the compass, as it seriously did not like being anywhere near the rev-counter. I still get a wild swing when I start the engine as my starter cables run pretty close to it (can't avoid it) because the battery is behind the seat. All my layouts were 'trial and error' with a few large sheets of cardboard. However, it was a most enjoyable exercise on a winter evening and actually fitting instruments was one of the 'fun' parts of building. Have you ever noticed how folks always walk up to an airplane and stare at the panel as if that's the heart of the plane? They should be looking at the wings, as they are the real 'work of art'.
I have a Garmin 100 (12 years old now but still working). I wired the data feed wire to a 300mA green light which I placed right at the top of the panel so that whenever the GPS 'Msg' flashes -1 can see it when flying (I set up Proximity Alarms around our MATZ's over here - and it's handy to know when you're approaching a waypoint). I did this because the noise level and distance from the panel prevented me from hearing the message 'beep'. I mounted my panel at 5 points initially - but this was too stiff. I now mount at the bottom corners and top center with very soft mountings glassed into the fuselage.
Charles Kuhlman, Marshalltown, IA
Thank you for your efforts on the newsletter. It is always interesting and encouraging reading it.
Here is a brief update on the status of Q2 32DK. After I broke the canard on a bad landing (purely pilot error) in 1997,1 have been repairing the canard and elevator. The glass work is nearly completed. Only the re-fabricated section of the slot core has to be glassed on to the canard. The slot core is bonded in place but not yet glassed. The hard work, the glass and foam repair on the canard, is complete. Nearly all the micro work on the canard is contoured (except where the slot core glass tapes will go). My partner and I consulted with Scott Swing on the canard repair. I have documented the process via videotape and pictures. My partner and I feel confident the repair will be as strong as the original construction. It was much easier than constructing a whole new canard and attaching it. We added one additional layer of glass to the splice (top and bottom) than the plans call for and there is the additional micro to bond the new foam insert in place. It will be slightly heavier but a minor penalty for the time savings. While it is down, we intend to correct the axle alignment and add a second master cylinder for individual braking control. The main problem is my motivation to get out into the garage and work on it. I now have young children and acreage to take care of. When we were building, I was single and then married without children or property. Now family comes first. 1 am also in a flying club with a C-150. That satisfies some of the urge to fly, but it is not as much fun as the Q2. It could be completed this year if I would just get going on it. Thanks for your efforts to continue providing information and encouragement!
Perhaps we'll see you at Ottawa this fall. We would be glad to discuss our repair procedure after it is proven. When we started this process we were searching for anyone else who had done this, but could find no one. Now we will have some experience and can share it with others. The beauty of it is that if it ever fails or shows signs of problems, it will be on landing. As you know the canard sees its greatest stress upon landing, not in flight!
Ed Note: Charles Kuhlman and Harold Dirks Q2 incorporates a collection of unique solutions worth studying. I used almost a whole roll of film on their plane when they were last in Ottawa. I found their Q2 full of useful ideas. Keep plugging away, Charles and Harold, and keep us posted.
Ian Huss, Bolder, CO
I still have Super-Quickie 425IF. It has about 200 hours on it now and runs better than ever. I only manage to fly about 20 hours a year. Now that my Long-EZ 110EZ is flying, it is hard to go back! During the last year or so I've made a few half-hearted attempts to sell the Q1 and found no serious interest.
The last few years I've been kicking around some aircraft performance formulas and daydreaming a lot (a dangerous combination.) It occurred to me that a Super-Q with an all out climb prop, gearing and mixture control might have a shot at no less than FIVE world records. In a fit of ambition, I ordered new 60" blades for the IVOPROP, 2.58 : 1 gears and Arctic Sparrow mixture control for the Rotax. It turns out the gearbox needed an overhaul anyway and I never did like the 2:1 gears I had. The way I see it, the Super-Q has very little competition in its weight class. How many airplanes do you know of that are this slippery, this powerful and light? HMMMM...
By the way, (for the rest of you aspiring armchair designers out there), here's the formula that started all the trouble:
88 ( T - D) V
|Rate of Climb||=||_____________|
|Where::||L = Lift|
|T = Thrust|
|D = Drag|
|W = Weight|
|V = Velocity in MPH|
|88 is a constant|
( Use the same units everywhere else)
My book also says that "in unaccelerated flight the lift = weight (L=W) and thrust = drag (T=D)". So if you can guesstimate your ZERO THRUST glide ratio (like by stopping the prop and gliding around with a Garmin GPS), you can divide your gross weight by the glide ratio and get DRAG. I guestimeasure THRUST with a spring scale tied to the tail wheel during a static runup. I've tested this stuff and it seems pretty accurate. Take a look at what changing the weight does to your rate of climb. Rearrange the formula to solve for what you want. Am I the only one weird enough to think this is fun?
The cool thing about the IVOPROP is it's convenient ability to change pitch in a few seconds, allowing you to dial in the right pitch for what you want to do in a few minutes.
This brings up an interesting idea for anyone thinking about a first flight: When I prepared the Long-EZ for its first flight, I set the IVO for a static runup of 2700 RPM to test the engine and systems at full power a few times. Then I dialed IVO down to 2550 RPM static for the first flight so I'd have full power at best climb speed and man did it GO! 1700 fpm at 90 mph and I was at pattern altitude by the end of the runway! Most of the faster homebuilts have serious overheating problems on the first flight and both of mine were no exception. The IVO pitched way flat allows you to climb on the least possible amount of power and incidentally discourages you from "inadvertent speed envelope expansion." I also truly believe the IVO is a must for dialing in a new engine / airframe combination (especially two strokes) since you can't tune them until they're spinning up near redline. With a fixed prop you can't spin them fast enough until they're tuned right! Starting with the IVO would have saved me two or three months and several exciting rides during the test program on the Quickie,not to mention the two beautiful wall hanger props I have that don't work.
Ted Kibiuk, Holland Patent, NY
Received your QList literature and read each response thoroughly. Thank you for your efforts. I will start to repair the indentations this spring, time being available. So now when these indentations get repaired, tested and repainted it should be ready to fly again.
I put 118 hours and 205 landings on my aircraft and it flew beautifully. At 3200 rpm's I cruised at 125 mph. It took me 30 minutes to reach 6500 feet.
Prior to this, my engine, on the ground, would stop completely at high RPM's. Each time I changed all electronic parts, coil, points, plugs, etc. and the engine would run great again. These changes, however, were not related to an inflight engine failure that occurred later. When the engine failed, 1 attempted a forced landing. I banked to the right, in order to miss a high elm tree and hit the right wheel flipping over into the snow. I was buried until help arrived. For such a violent ground maneuver, the plane was relatively undamaged. I determined what caused the engine to stop. The push-rod pin, from the engine cam to the points, housed in an aluminum bushing, had a tiny gouged-out bur - hook on it. As it ratcheted in the aluminum bushing, it would find a tiny indentation in the bushing and hook on to it, stopping the engine. I removed the hook, removed the push-rod pin (1 1/2" x 3/16" diameter) and have resolved the engine failure problem.
Thanks again for your input.
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