It had logged 1962 airframe hours and 1428 takeoff and landing cycles and was powered by two CFM International CFM56-5B5/P engines.

The transponder, which lets the ATC track down Flight 6074, was also knocked out, disabling the controller's ability.

Ten minutes before a shift change, the ATC noticed that Flight 6074 disappeared from radar.

Fearing the worst, the ATC asked the pilots of AAL63 to descend to 31000 feet (FL310) and if they could see EasyJet Flight 6074 in their TCAS, but AAL63 replied negative.

[1]: 41  Before landing, several attempts were made to contact ATC using mobile phones without success.

It's an essential part of the aircraft's electrical system, providing power for critical in-flight functions.