To: Nick lappos
Nick Sez:
“FAR 27.351 (and all other FAR/JAR) does NOT call for any testing of full pedal inputs!
The FAR that Lu incorrectly reads says:
"Sec. 29.351 Yawing conditions.
(a) Each rotorcraft must be DESIGNED FOR THE LOADS RESULTING FROM the maneuvers specified..."
Lu Responds:
Nick I would strongly suggest you read my post. Your statement above is 100% correct as it reflects FAR 27.351. If you look closely at my post shown below I quoted AC-27-1, which is the Certification of Normal Category Rotorcraft. Get a copy of it and read under paragraph 27.177 titled Static directional stability. Paragraph a. reads EXPLANATION. This rule requires that positive static directional stability be demonstrated at the TRIM airspeeds defined in 27.175. The trim speed for climb is Vy and for cruise 0.9Vh or, 0.9Vne (whichever is less). The next two paragraphs and sub paragraphs describe the test setup and the test itself and these tests are required for certification. I would also suggest you read paragraph 27.175 as it sets the groundwork for the test. Also, read the Code of Federal Regulations quoted in my post. I think you will find this reading enlightening.
My original post:
AC-27-1 paragraph 27.177.b.2 recognizes that some helicopters experience excessive flapping of the main rotor and tail rotors when the helicopter is in a sideslip. To establish this side slip/flapping limits the respective rotors should be instrumented. CFR-14-27.177 requires testing of the controllability at side slip angles of plus ten degrees, left and right, and CFR-14-27.351 requires full deflection of the tail rotor pedals (left and right) while airborne from 0 to 0.6 Vne to attain a 90-degree sideslip.
What is your favorite flavor?