Roy Smith wrote:
snip
: Here's the strange part; the yellow "Gear in Transit" light came on
: during the dive, as if the auto extension system thought we were trying
: to land. The gear didn't actually extend, but the light came on and
: (IIRC) the warning alarm when off too. I don't remember the exact speed
: this happened at, but it was certainly well above Vlo.

: Anybody have any idea what might have caused this? The auto extension
: system relies on a combination of airspeed and throttle setting, but
: both were well outside the normal operating conditions to trigger a gear
: extension.

I just checked the service manual. The "Gear in transit" light is connected
to the "up limit" switches. Recall that the Arrow gear is held up with
hydraulic pressure - there are no gear uplocks. If there is a leaky
hydraulic actuating cylinder or control valve, the gear will gradually
sag until one of the "up limit" switches opens. The "Gear in transit" light
comes on, as does the hydraulic pump, and the gear goes back up, closing
the "up limit" switch. I see this occasionally on an Arrow one of my friends
flies. There is also a pressure switch on the hydraulic system, to shut the
pump off when the gear is fully extended or retracted.

I don't think the auto extender is the culprit. If you are concerned,
have a mechanic put it on jacks, retract the gear, shut off the master,
and go to lunch (or home for the night). Then check which gear has sagged.
There's a nice flowchart in the service manual, as well.
--
Aaron Coolidge (N9376J)