December 14, 1994
NTSB Number AAR-95-04
NTIS Number PB95-910404
On December 14, 1994, about 1146:23 pacific standard time, a Phoenix Air Group, Inc. (Phoenix Air) Learjet 35A, registration N521PA, crashed in Fresno, California. Operating under the call sign Dart 21, the flightcrew had declared an emergency inbound to Fresno Air Terminal due to engine fire indications. They flew the airplane toward a right base for their requested runway, but the airplane continued past the airport. The flightcrew was heard on Fresno tower frequency attempting to diagnose the emergency conditions and control the airplane until it crashed, with landing gear down, on an avenue in Fresno. Both pilots were fatally injured. Twenty-one persons on the ground were injured, and 12 apartment units in 2 buildings were destroyed or substantially damaged by impact and fire.
The National Transportation Safety Board determines that the probable causes of this accident were: 1) improperly installed electrical wiring for special mission operations that led to an in-flight fii that caused airplane systems and structural damage and subsequent airplane control difficulties; 2) improper maintenance and inspection procedures followed by the operator; and, 3) inadequate oversight and approval of the maintenance and inspection practice by the operator in the installation of the special mission systems.
Safety issues in this report focused on maintenance, inspection and quality assurance. Safety recommendations concerning these issues were made to the Federal Aviation Administration, Phoenix Air, and the Department of Defense.
As a result of the investigation of this accident, the National Transportation Safety Board makes the following recommendations:
To the Federal Aviation 'Administration:
Publish an FAA Special Airworthiness Information Bulletin that describes the circumstances of this accident, including the consequences of improper installation of the special mission wiring, where electrical power wires were unprotected by current limiters. In addition, emphasize that all major aircraft repairs and alterations requiring an FAA Form 337 must be performed in strict accordance with the technical data contained in the FAA Form 337, and that it is unacceptable to use similar work done on another aircraft as a technical guide in lieu of the information on the FAA Form 337. (Class II, Priority Action) (A-95-79)
To the Department of Defense:
Centralize contractual oversight for safety for all Department of Defense components using contracted aircraft services. (Class II, Priority Action) (A-95-147)
To Phoenix Air:
Conduct an in-depth audit of your maintenance program to ensure that all work is being done in accordance with applicable Federal Aviation Regulations, and particularly to ensure that mechanics and others involved in aircraft maintenance are consulting proper technical data when performing and inspecting aircraft. (Class II, Priority Action) (A-95-80)