20150313003109I

On 3/13/2015, while on approach to Lincoln Park airport (NO7), a rockwell Commander aircraft (N7MA) had an indication that the nose landing gear was not fully down and locked. The pilot cycled the landing gear, at which point he confirmed that the required three down and locked green lights where on. He then, contacted a helicopter flying nearby and ground personnel (names not available) to verify that all three landing gear were down. Upon receiving verbal confirmation the pilot continued the approach and landed the aircraft. During roll out the nose landing gear collapsed causing the propeller to contact the runway bringing the aircraft to a full stop.

During the post incident investigation of the aircraft the following issues were discovered.

1) The aircraft was being relocated from sussex county airport (kfwn) where maintenance (unrelated to the landing gear system) had just been performed. The pilot said he was unaware that the maintenance performed was not entered into the aircraft log book, nor was he provided with a log book entry before taking the aircraft and departing for Lincoln Park.

2) A video that had been taken of the aircraft landing clearly showed the nose gear was not fully extended and in the down and locked position.

3) After the aircraft was towed into a hangar and placed on jacks, the nose gear actuator was disconnected allowing the nose gear to move freely into the full down locked position.

4) Power was then applied to the aircraft and when the landing gear lights were checked, they indicated right and left main gear down and locked but the nose indicated not down and locked (no light).the bulb was checked using the system press to test and was determined to work normally. Even with the actuator disconnected, the nose light should have been ?on?. This indicates that there may be a fault or multiple faults in the indication circuit preventing the light from coming on or giving a false green indication when the gear was not down and locked. This could explain why the pilot said he had three green lights when the gear was not down and locked.

5) Inspection of the fluid level in the hydraulic system reservoir was checked and found to be below the lowest readable levelof the unit?s dip stick indicating there was little or no fluid in the system. The lack of fluid in the system could have prevented the nose actuator from fully extending.

6) Damage to the nose landing gear actuator shaft suggests the actuator was not fully extended by approximately 2 inches.

On 3/20/2015 the actuator was removed and sent to the manufacturer for tear down and evaluation. Any additional pertinent information from the results of the actuator tear down, hydraulic system low fluid level and the malfunctioning landing gear indication circuit will be added in an amendment to this report.

Amendment may 5, 2015- after being contacted by the actuator manufacturer, it was determined that the actuator was operating normally and the tear down indicated it had all the correct seals and o-rings installed.

With this new information, it is determined that the most probable cause of the nose landing gear not fully extending would be the lack of hydraulic fluid in the system. This, connected with the failure of the pilot to follow the aircraft emergency checklist and pull the emergency landing gear extension handle are the most likely probable of this incident..

This incident is now closed. No further action to be taken.