Originally Posted by
JohnDixson
Thanks, CTR-looks like higher harmonic control is headed for a real flight evaluation.
Real flight tests of a higher harmonic control was conducted by Hughes on a OH-6 in the early 80”s. Lot of pre-flight press and zero coverage post test flights. Those in the know indicated that the mechanical components between actuators and blade beat themselves to death in a very short period of operational time. Concept shelved as impractical.
Even with moving the entire thing to the rotating system, who thinks individual independent blade control is a good idea? There are so many failure modes the system safety assessment would be a nightmare (except for Boeing who doesn’t bother with such trivia). Any failure due to mechanical, wiring, electronic, or environmental (lightning) which results in the loss of pitch control to one blade is a catastrophic event which requires 1 in a billion level of reliability. So everything has to be independently triple redundant and impervious to common mode failure (lightning again). Concept impractical at the the most casual analysis.