I have seen similar variations of speed in smooth air. I think
that was one of my problems in hand flying and holding
perfect pitch. When I have had Arnie flying along side, I
occasionally gets comments like "Why'd ya slow down?" As you have
seen, there is no indication in the engine data.
Are we marginally losing laminar flow from time to time? Have
others noticed this? And, the ever imponderable, "Why?" Does it happen
in a certain speed range? Altitude? Bug contamination?
I've noticed this in cruise, a smooth variation of
+/- 3 or 4 knots TAS. I've always attributed it to changes in the wind, that
is, very small wind shears. However if you and Arnie were tip to tip and you
experienced it and he didn't....that would pretty much ruin that theory. Hey,
maybe you were eating that sandwich at the time and increasing your
weight....uhhh, naa. Solar winds? Coriolus effect? A warp in the time-space
continuum? I'm outa ideas.
Bill Harrelson
N5ZQ 320 800+ hrs
N6ZQ IV 0.003% (it'd be
higher if I'd get off the computer and get back to
work)