Narrative
A pilot on an instrument flight rules (IFR) flight plan encountered ice accumulation while in instrument meteorological conditions (IMC). He requested a precautionary diversion to the nearest airport. After exiting IMC at 1,642 feet above ground level, he circled overhead to land. The pilot reported keeping the flaps and landing gear retracted to avoid adversely affecting lift, then forgot to extend the landing gear before touchdown. As the airplane crossed the runway threshold, the pilot reduced power, causing the auto-extend function of the landing gear system to attempt extension. During the subsequent landing roll, the right main and nose landing gear collapsed. The airplane slid off the runway to the right, sustaining substantial damage to the right wing.
Aircraft and System Details
The airplane involved was equipped with an airspeed-power sensing backup gear extender, as described in the Procedures section of the Piper Arrow II Pilot's Operating Manual. The manual states: "Some aircraft are equipped with an airspeed-power sensing system (backup gear extender) which extends the landing gear under low airspeed-power conditions even though the pilot may not have selected gear down." It further notes that for normal operation, the pilot should use the gear selector switch. The manual also specifies that a red gear warning light and horn activate simultaneously when the backup system has lowered the gear and the selector is not down with the throttle not full open.
Pilot Actions
The pilot stated that there were no preaccident mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The landing gear collapse was attributed to the pilot's failure to extend the gear prior to landing, with the auto-extend function activating upon power reduction.
Aftermath
The airplane came to rest off the runway, with substantial damage limited to the right wing. No other damage or injuries were reported in the source.