Flight crew flying BE400A aircraft reported uncommanded nose landing gear extension in cruise flight.
Synopsis
Flight crew flying BE400A aircraft reported uncommanded nose landing gear extension in cruise flight.
Narrative
I (PIC) was pilot flying; SIC was pilot monitoring. We were in descent from FL230 to 12;000 feet. Coming through an altitude around 17;000 feet; at an airspeed between 315 and 320 KIAS; we experienced un-commanded deployment of the nose gear. The nose gear could be heard and felt to descend; and indicated down and locked. The gear handle was verified in the UP position. I reduced power to idle; deployed the speed brakes; disengaged the autopilot and raised the nose to reduce airspeed. I maintained the aircraft in a gentle descent; near level altitude and we attained 200 KIAS (VLO/VLE) at an altitude just below 16;000 feet. From there; we continued the descent at a speed below VLE. I contacted ATC to let them know our situation and at that time advised them we were not yet [requesting priority handling] but would advise them of our intentions. We then consulted the checklist and found no checklist for un-commanded gear deployment. We discussed the situation and our options. As the gear had deployed nearly 120 KIAS above its limiting speed; and was now showing down and locked; we elected not to attempt to recycle the gear. We did not want to risk the possibility of the gear retracting; then being unable to extend again. As we were already nearly at the destination and in a descent; we elected to land at our destination airport. Given the possibility of gear damage due to its high deployment speed; we [requested priority handling] at this point and requested emergency services be standing by at ZZZ. On arrival at ZZZ we were able to extend the main gear normally and received normal gear indications - three green lights; no red lights. We performed a visual approach to RWY XX and a flyby of the tower at 500 feet AGL. Tower indicated the gear appeared to be undamaged. We performed a visual traffic pattern and executed a normal landing. No further abnormal indications were noted. Cause: Malfunction in the landing gear system. Suggestion: Maintenance of landing gear system.
Second reporter narrative
Nose gear extended and locked in cruise flight. Reduced airspeed to below 200 knots indicated; descending per ATC instructions. [Requested priority handling] and requested services be ready and deployed. Upon arrival in ZZZ airport traffic area and communications with the tower requested low pass so tower employees could verify landing gear appears down and locked. Confirmed as best we could flew VMC pattern and landed RWY XX without incident. Taxi into and shutdown at FBO. After deplaning passengers inspected nose gear thoroughly; no obvious damage. Cause: No idea. Suggestion: Difficult to answer; never experienced such a failure in XX years of flying.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.