REFLECTOR: High speed taxi part 2 w/nose lift

[Brian Michalk]

Lifting the nose under engine power can result in an unintended first 
flight.  The procedure I was taught is as follows:

In increments of five knots, bring the plane to the desired speed
pull power to idle
attempt to lift nose
test aileron authority
repeat at higher speed

You can find the speed at which the nose rotates, however it probably 
won't be the same speed while under power.  My rotation speed under 
power was perhaps ten knots higher.

On 5/25/2012 1:32 PM, Chris Barber wrote:
> After getting my DAR inspection and Repairman Certificate a few weeks ago, I did two high speed taxi test with disappointing results. The engine temps on my two rotor 13b rotary were extremely high. Well into the 250 degree range after the long taxi (9000 foot runway) and the quick jaunt down 17R. Obviously unacceptable. I did seem to avoid engine damage apparently by grace and the short duration.
>
> Over the last few weeks I have focused on cooling mods. This time I followed the advice from Paul Lamar's book "How to Cool Your Wankle" more honestly and put the oil and coolant heat exchangers under the engine and a bit into the airstream for solid ram air.
>
> Today I repeated the long taxi for high speed taxi test 3. Outside temp was 96 degrees. Temps down Hotel stayed around 165 degrees to Alpha. I had to wait for a Grauman to take off. Ran the engine up a bit to verify mixture. By the time I called the tower to take the active coolant temps had gotten to about 185.
>
> I took a breath and smoothly added power and started my run down the center line. Speed came in as I brought power to just over 5000 RPM. I reached 60 knots really  quickly. (posted rotation speed range). I retarded the power a bit to maintain 60 ish knots took a mental breath....and raised the nose. The nose actually lifted  Holy crap....that is almost flight. I brought back power and the nose settled (uh, by settled, I mean bounced ;-)).
>
> Ok. While really cool to me, the coolest part was when I noticed that when I checked the coolant temp just as the nose was down, the coolant temp had DROPPED to the high 170's. A drop. Imagine that!!!
>
> I pulled off at Charlie and taxied back to my hangar with the temps around. 185. They just hit 190 before I shut down. Again, it is in the mid 90's today.
>
> I don't know about y'all, but this has been a pretty good day off so far.
>
> Thanks for your support.
>
> Chris Barber
> Houston KEFD
> Velocity SE/FG
> Rotary 13b turbo w/Mistral Intake
> RWS PSRU/EC2/EM2
> Dynon SkyView SV-7
>
> Sent from my iPhone 4
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