Accident Overview
On 14 November 1997, at 2103 hours local time, a Cessna Centurion 210L, registration N-210NP, operated as a private IFR flight from Nîmes Garons to Geneva-Cointrin, experienced a landing gear malfunction during approach. The aircraft had two occupants on board.
Sequence of Events
After being cleared for an ILS approach to runway 23, the pilot extended the landing gear lever but did not receive the green down-and-locked indicator light. He raised and lowered the lever again without success, then notified air traffic control and requested to enter the holding pattern at St-Prex radio beacon. In the hold, the pilot attempted to diagnose the issue, checked the indicator bulb, and performed the manual extension procedure from the checklist, all without success. The orange gear-up light also failed to illuminate. The pilot then requested a low pass for a visual check of the landing gear, but darkness prevented any confirmation.
Both occupants visually confirmed that the two main landing gear legs appeared extended, and the pilot decided to land on the concrete runway with the nose gear retracted. He maintained a nose-high attitude as long as possible, but the nose eventually dropped and scraped along the runway surface. After several dozen meters, the aircraft came to a stop. Firefighters responded quickly, and both occupants exited the cabin uninjured.
Damage to Aircraft
Damage was limited to the propeller, engine cowlings, and exhausts.
Investigation Findings
Examination revealed that the nose landing gear doors remained closed. When opened, the nose gear could be extended and locked using the manual hand pump. The nose gear doors were actuated by an electrovalve (solenoid). The Cessna Centurion 210NP had undergone a factory modification that eliminated the main landing gear doors. Bench testing of the solenoid responsible for opening the nose gear doors showed a malfunction (contact remained closed), preventing extension of the nose gear.
The manufacturer recommended overhaul of this solenoid every five years. The subject solenoid had been inspected two years prior and had operated normally for about 250 flight hours.
At the time of the accident, the Geneva METAR reported CAVOK conditions with QNH 1018 hPa.
Operational Aspects
The pilot reacted appropriately by announcing the issue and entering the holding pattern to allow time for troubleshooting and manual extension attempts. After unsuccessful attempts, he requested a visual check from the ground, which was not possible due to darkness. The decision to land with partially extended gear was considered prudent, and the execution resulted in minor damage.
Technical Analysis
Bench testing showed that the defective solenoid prevented nose gear extension in both normal and emergency modes as long as the landing gear control circuit remained powered. The nose gear extension cycle was interrupted by the blocked nose doors. The only possibility to extend the nose gear would have been to momentarily cut electrical power to open the solenoid contact, then use the manual hand pump to lock the gear. This procedure was not included in the manufacturer's checklists.
Probable Cause
The accident was due to a landing completed on the nose following an inability to fully extend the landing gear, caused by the defective operation of a component in the landing gear control system.