The well done award

Flying Safety, May, 2003 by James E. Bower, Michael G. Fuller

On a cross country, Lt Col Jim Bower (IP) and Maj Mike Fuller (front seat pilot) experienced a near-complete electrical failure in a newly modified T-38C. Prior to engine start, with external power applied, a problem with the VOR pointer was noted. After, maintenance, the aircraft was idled for more than 15 minutes to ensure the VOR functioned properly. Then the crew took off for their first refueling stop at Dyess AFB, TX.

While cruising at FL 370 north of El Paso, above a solid undercast of unknown height, they received clearance to proceed directly to Dyess, where the field was VFR with a scattered, layer at 12,000 feet and multiple layers below. Handed off to Fort Worth Center, Lt Col Bower reported in.

An unexpected silence on the headsets coupled with blank displays caught their attention. Without warning, the right essential AC bus failed, causing a loss of electrical systems including all radios, intercom, navigation and engine management systems, normal landing gear extension system and nose wheel steering. While Maj Fuller flew from the front cockpit, Lt Col Bower hacked his watch to initiate time and heading navigation. The EGT had indicated 225 miles and 27 minutes to go about a minute earlier, so they calculated fuel remaining at 1000 pounds. The checklist for Mission Data Processor Failure says to proceed to VMC as soon as possible; however, the undercast posed a challenge. A "sucker hole" appeared about 20 miles ahead, but they did not know what the ceilings were below the cloud deck, and they calculated the fuel bum rate at lower altitude would preclude making Dyess safely unless they stayed at altitude for another 15 minutes. Communicating with notes and hand signals, the pilots decided to conti nue at altitude and proceed using timing and the standby compass. The standby ADIs worked for approximately six minutes, as advertised, before beginning to tumble.

Twelve minutes out, they initiated a VMC descent, found a clearing line and continued the descent while maintaining visual contact with the ground. Leveling the aircraft at 10,500 feet, Maj Fuller noted a DME began to increase at 30 miles. The crew initiated a left 90-degree turn toward north to start "homing" via the DME.

About three minutes later, Dyess appeared at their 1130 position. They elected to fly a south-to-north electrical failure pattern to alert the tower. Not knowing their fuel state, and wanting to minimize their time aloft, they executed a modified left teardrop to a straight-in final. When the landing gear did not lower normally, they used the alternate gear extension. With only the main gear lights illuminated, the pilots realized the nose gear light would not function with total DC electrical failure. Flaps were lowered and visually checked down. Maj Fuller flew a 170-knot approach to an uneventful full stop.

Post-flight inspection revealed a damaged circuit breaker and an unexpected design problem. The incident uncovered a single-point electrical failure node in the T-38C modification that was quickly corrected.