AR-1 gyro manufacturer
- Oct 31, 2011
- Tampa, FL
- Total Flight Time
- 4000+ 472 gyroplanes. Sport CFI Gyro and Trikes
From a standing stop to unstick in about 10 seconds, suggests a stronger headwind. But, accepting your figures, wouldn't the take-off have been even shorter beginning with 300 RRPM? Rhetorically asked, can the U-jointed AR-1 be power-prerotated to 300 RRPM with significant back stick, and, if so would such reduce the service life of the prerotator components (the U-joint in particular)?
MTO Sport 2017 and new Cavalon still use U joints and they pre-rotate to 300+ RRPM but they do not recommend pulling the stick back to do it but forward, actually technically just forward of neutral not completely forward
Yes the upper U joint deteriorate faster if the pre-rotation is done with stick back and they should be changed out faster if that is being done. However, let me ask how many people and how many times do they have to do this "short" takeoff roll where it is really needed. The only ones they need this done continuously and spend $100 every 2-3 months to replace the U joint constantly would be those who takeoff constantly from a very short strip or very bad soft field. Otherwise this technique would be used only when necessary
We prefer the flexshaft prerotator for reasons already stated, and we've the brakes to hold engine thrust for 300 RRPM. Other firms choose the U-jointed driveshafts. To each their own.
That's great. Flexshafts are available off the shelf. Tom Milton's old company offers them. If you can show that compared to pre-rotation to X RRPM with stick forward versus pre-rotation to the same X RRPM with stick back makes a significant difference in nil wind on the same gyro to clear 50 foot obstacle (the standard definition of takeoff distance), that would be a good thing to see and consider.
fara, in this thread I've read of no "promoting" these company test pilot steep climbs (yours included) as "official ways of takeoff procedure." For the typical owner, it is safest to stay in ground effect after take-off until at least Vx or Vy has been achieved. This completely avoids the H/V danger zone.
Good to hear your proper recommendation to build speed to Vx before starting climbout. That is where the real short field takeoff distance is measured at gross weight with zero wind at sea level 59 degrees F. All standards of compliance ask for that or rather ask for a speed from which you can recover after an abrupt engine out from any height during initial takeoff