Livermore Muni Airport
Aircraft Accident/Incident Report

Livermore, California 94551
Friday, December 23, 2005 15:20 PST

The airplane collided with terrain 9 miles from the destination airport. The pilot was cleared for the instrument landing system approach into the airport. During the descent, the airplane was below the glideslope but tracking the localizer. The pilot contacted the air traffic control tower controller and was cleared to land. The last recorded radar target for the airplane was at 1,600 feet mean sea level (msl) and the initial impact occurred at 1,400 feet msl. The radar data indicated that the target maintained a descent rate of about 1,100 feet per minute during the last minute of flight and was flying at a radar derived ground speed of approximately 112 knots. Though the en route controller received a minimum safe altitude alert (MSAW), he had transferred control of the airplane 1 minute prior to the receipt of the initial MSAW alert. However, the airplane crossed a named intersection at 3,300 feet msl after it was cleared to cross the intersection at 4,000 feet msl while under the en route controller's control. The en route controller did not advise the pilot of the altitude deviation. The air traffic control tower controller did not issue an MSAW to the pilot, even though the equipment was configured to receive MSAW alerts. The tower controller said that he did not recall receiving the alerts and no recording was available to indicate whether or not an aural MSAW alert was received. An evaluation of the operation of the MSAW alerting system following the accident showed that it was functional. Examination of the airframe and engine did not reveal any mechanical anomalies to preclude normal operation. Metallurgical examination of the altimeter showed that the 10,000-foot pointer was not at its correct position at the time of impact and at an undetermined time prior to the accident, moved aft on its shaft and became loose. The effect of the 10,000-foot pointer on the pilot's flight performance could not be ascertained with the available evidence.

The pilot's failure to maintain the appropriate glidepath alignment during an instrument landing system approach, resulting in collision with terrain. A contributing factor to the accident was the failure of the air traffic controllers to issue a minimum safe altitude warning (MSAW) alert.