On a sunny day (Wed, 6 Oct 2021 00:14:56 -0700 (PDT)) it happened Michael Terrell snipped-for-privacy@gmail.com wrote in snipped-for-privacy@googlegroups.com:
Yes the thin air issue is true. But they just did speedup rotor speed
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From that link: Analysis of the Sept. 18 preflight test has shown that two of Ingenuity's servos oscillated slightly during the "servo wiggle" checkout. The team is still trying to determine the cause, but it may be due to increasing wear
More here:
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