Loose wire caused Afghanistan Global Hawk crash

Flight Global ^ | 3/7/2012 | Zach Rosenberg

[U-238]

In-flight electrical failure caused a Northrop Grumman EQ-4 to crash in Afghanistan on 20 August, says a newly-released accident investigation report. The aircraft crashed approximately 195km (120 miles) northwest of Kandahar.

Specificlly, an electrical connector to an unidentified line replacement unit partially separated. This caused electrical damage inside the LRU, which cut power to the actuators that controlled ailerons and spoilers. Within 1min of the power failure, the aircraft lost control after hitting minor turbulence.

"The Board President also found, by a preponderance of the evidence, that LRU installation methods were a contributing factor in the mishap," continues the report.

After a satisfactory preflight inspection, the aircraft departed a forward operating base - likely Al Dhafra air base in the UAE, the region's main Global Hawk operating base - and entered the area of operations over Afghanistan. Approximately 9h into the flight, remote pilots and payload operators lost contact with the aircraft. The same connector controls aircraft inputs to the aircraft's wing-mounted flight control surfaces, making the aircraft impossible to control.

After 25s of level flight the aircraft entered a high-speed dive from its 15,500m (51,000ft) cruise altitude, which it maintained until it hit the ground. The report suggests that the wings and other pieces were sheared off during the descent.

[RitchieAprile]

LRU - procurment jargon for “Line Replaceable Unit”

[wrench]

There is a reason safety-wired cannon plugs are used in aviation. Very secure, and easy to inspect at a glance.

[Bellflower]

One little perfectly placed loose wire...mmm?

[itsahoot]

Translation: Some enlisted guy is going to pay big time.

[Paperpusher]

The pictures of drone show it remarkably intact for a crash of that magnitude.