Flight testing...

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Any flight testing should only be done by a pilot who is proficient and current in the type or similar aircraft. Anything else is stupid and asking for trouble.
If you don't meet that requirement, get someone else to fly it who does meet it. Get proficient in an airplane that is flown regularly and is unlikely to surprise you with issues.
 

djmcfall

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I have heard of many low time pilots trying to teach themselves to fly by “just high speed taxi” up and down a taxi way or runway, when by surprise they were airborne. Most of the time ended up with a damaged aircraft.
 

Twodeaddogs

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Not sure who you are replying to. But for me, I know about flying triangular courses, cloverleafs, 4 sided, and timed climbs.

My issue is keeping accurate constant speed an d/or pitch and/or climb rate
Use your AH correctly. Try climbing at a pitch attitude and holding. 3 degrees up or 5 up. Trim it out for the pitch and accept the airspeed.
 

Hot Wings

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Are these planes of known type? If so and there is a users group that would be a good place to start asking specific questions.
If these are unique aircraft (all EABs are unique in some way) then this is what the FAA has to say on the subject of flight tests:

 

Marc Zeitlin

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rsrguy3

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Well the escrow closed today, so it looks like I'll be moving a zenith 801 with a new from pzl 220hp motor next week... on a trailer to our hangar an hour north. We'll get a complete condition inspection completed and begin the test program.... Also, who puts an MT cs prop on a zenith....? lol
 

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N804RV

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My issue is keeping accurate constant speed an d/or pitch and/or climb rate
I used my little Sonerai to try out some flight testing 'technique' in anticipation of doing the phase I on my RV-8. For just one flight test card, "best-glide speed", I made a total of 30 passes in one flight.

Holding airspeed precisely constant for each data point was challenging. The little Sonerai is very responsive. The trim system is marginal. And, stick forces are pretty light. I expect my RV-8 will be similar.
 

jedi

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A lot of discussion about high speed taxi, crow hops and alternately just go for it. The decision of what to do has a lot to do with the design as well as pilot skill level. In a well known design with many prior successful first flights of the design the "just go for it" may be ok. For a one off unusual design I would want to test the controls before committing to flight. This can be done as a part of the go for it flight but be prepared to abort the flight at any point.

Note that Boeing does an aborted takeoff prior to every first flight even after building six thousand 737s.

IMHO a pilot that does not have the skill to do a crow hop on a sufficiently long runway should not be doing the first flight of that craft.
 
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Twodeaddogs

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I had a situation one time when a builder, waiting for me to turn up to do the final inspection before first flight, got impatient and decided to do some high speed taxying. He hadn't removed all of the small inspection panels but some were off. He got it into his head that it was ok to do a fast run down the runway and pull to a halt at the end. He got some surprise when the aircraft took off and was out over the hedge before he could react., so he had to do a circuit and land, giving himself a thorough fright in the process. He taxied in and parked and was a very chastened man when he climbed out. He particularly remembered the noise inside the aircraft as the wind got in thru the holes left by the panels sitting on his bench. He even got a bonus earful from his wife, after I had finished with him. As far as I'm concerned,an aircraft should not be fast taxied or crow hopped unless it is in a fully flight ready condition.
 

BJC

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He got some surprise when the aircraft took off and was out over the hedge before he could react.,
One technique for avoiding that, should one be compeller to do fast-taxi testing, is to set the power before starting the roll, beginning with a small amount of power, and gradually increasing it on following test until the speed is adequate to raise the tail for a conventional gear aircraft, of raise the nose wheel for a tri-gear.


BJC
 

jedi

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With regard to taxi test and "set the power before starting". That works well for initial taxi testing but when you get closer to "lift off" or "tail up" speed it is better to set one power for initial acceleration to just below the desired speed to get more time to assess handling qualities at that condition. It also depends on the power available. Some aircraft may need full power to get to that speed and then abort within the length of the available runway. Other aircraft, the Gee Bee Super Q.E.D. II for example, you may want the first takeoff to be at half throttle. Gee Bee Super Q.E.D. II

I wish I could have seen the first take off from the short grass strip, WN42, Cawleys South Prairie. 290 foot elevation. 2,600 feet long.
 

TFF

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I think the Boeing test pilots tend to have just a little more experience than the averaged homebuilder. Most of the time home builders don’t have experience with more responsive planes which is what they tend to build. Even a Flybaby is a hot rod Cub in essence. A lot of scratch built planes are not as straight as kit built and kit built aren’t as straight as fast build. Doesn’t mean they are bad, but they can be much more of a surprise over a 150. A lot of pilots learn they really are still students in handling something different.
 

pittsdriver

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I have done 16 initial test flights in a variety of homebuilt aircraft. I do not fast taxi/crow hop. I don't know why the EAA syllabus has this still as there has been a lot of airplanes wrecked. I taxi fast enough to burn in the brakes and to get an airspeed indication no faster. I can tell if the airplane rolls straight and if it has enough control on the ground. I agree that an experienced pilot should do the initial test flights until the airplane is sorted out. You have to be able to fly an airplane without even thinking about it if you have to deal with an inflight problem and most GA pilots are not capable of doing this. I know it is the greatest feeling in the world to do the first flight on an airplane you built but I have seen it come to grief many times.
 

flitzerpilot

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There is a salutary story about a pilot who, having built an open cockpit, radial engined biplane decided to perform his own test flight despite never having flown anything like that perviously. He weighed only 140 lbs and was short of stature and had increased the depth of the main fuselage tank (unnecessarily, as the main and bilateral tanks provided 20 Imp gals) such that no 'normal' sized human beings could reach the rudder pedals as their shins collided with the base of the tank.

After the remarkably short take-off in which he had not even fully opened the throttle, overwhelmed by the noise and slipstream, he found himself at about 1000' before he'd collected his thoughts, only to discover that he had no functioning ASI. Handling was fine, but he had no prior appreciation of the picture he should expect on approach, especially as no view over the nose would be available in the flare. The descent was steep and only in the last few hundred feet did he realise he was probably mushing, he applied some power, but hit hard on the left wheel, then onto the right and finally the right wingtip bow, which broke. The aircraft started to cartwheel, but he finally woke up and slammed everything into the left hand corner and amazingly managed to fly out of the situation: flew a circuit and slammed it on again but this time kept it straight. He then discovered that he'd connected the pitot/static lines in reverse.

Later having fixed this and the wingtip, he commenced some high speed tail-up runs. with throttle slam closures to 'assess the landing characteristics' sic.). Now a Stummelflitzer Z-1R has a geared engine and drives a relative huge propeller, hence the ground angle is steep, probably 17 degrees, so the precessional effects when raising the tail at full power are only exceeded by slamming the throttle closed and dropping the tail when there is no propeller slipstream to assist ruder control. Experimenting with brake at this point is pretty fraught, but new brakes had been fitted so he continued with the tests.

Now I would not do this in a Cub which is so safe it will only just kill you. Doing this in a small, relatively high-powered biplane for something like an HOUR is asking for trouble when one is likely to be gaining (over) confidence or perhaps tiring. inevitably he got his wires crossed with rudder, throttle, elevator and brake and performed a dramatic ground loop which quickly evolved into a cartwheeling somersault which totalled the ship. It remained for a while in the corner of a hangar, a pile of wood, fabric and wire in which he was lucky to have extricated himself without injury. Sadly his ego recovered faster than the aeroplane which he blamed for the accident.

I later learned that instead of a bladed tailskid (or tailwheel) which is mandated on the drawings, the builder had fitted a large spoon-shaped skid shoe, resulting in a very slippery tail end which was guaranteed to give trouble even to an experienced pilot.

Last I heard he was going to modify it in some way, without consultation with the designer. Another Z-1R is regularly flown and aerobatted without drama, I am happy to say, extending its owner's performance repertoire. :0)



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TFF

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A friend sold a one seat Jodel. The person who bought it said he could handle it. Gave the money over and went to test it. Did one touch and go and that must have spooked him. He couldn’t get it down after multiple attempts and ended up stalling and spinning on the airport perimeter. Killed him enough. That may have not been a first test flight, but it was one for the pilot. Most homebuilts are a hot rod compared to its parts donor. A Baby Ace is a hot rod Cub. An RV7 is a hot rod Mooney. Except for the minimalists, most homebuilts take an engine off a bigger plane and put on a smaller. The first Pitts started off as a cut up Taylorcraft. None requires super human piloting skills. They do require respect and your skills up to that task. People who flew the SR71 are not special in that they flew it like a cowboy, they flew by respecting the numbers. Take off at xxx speed, land at yyy, approach at jjj. Their skill is in not letting the plane fly them. Flying is not sight seeing. You might get some in between doing pilot stuff, but sometimes you don’t get any. If you want to sight see, get a co pilot. Control of the plane is the joy. That is what is suppose to be special. Mastery.
 

BJC

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A neighbor sold a CH-701. The neighbor, an ATP CFI offered to fly with the new owner for familiarization. New owner declined. Neighbor suggested calling an insurance agent. New owner declined. New owner departed. New owner totaled the airplane on his first attempt at landing.


BJC
 
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