Nightmareliner 

Wednesday, May 6th, 2015

Apparently, Boeing’s 787 has another problem. This one is caused by an integer overflow bug, which basically means that eventually the airplane counts so high that it goes a little nuts. Yes, really.

From the FAA directive on the issue:

…a Model 787 airplane that has been powered continuously for 248 days can lose all alternating current (AC) electrical power due to the generator control units (GCUs) simultaneously going into failsafe mode…We are issuing this AD to prevent loss of all AC electrical power, which could result in loss of control of the airplane.

Oh. Shit. Well, that’s alright I’m sure. After all, the FAA directive also gives clear directions on avoiding the issue:

(g) Repetitive Maintenance Task: Electrical Power Deactivation

At the latest of the times specified in paragraphs (g)(1), (g)(2), and (g)(3) of this AD, accomplish electrical power deactivation on the airplane, in accordance with step 2) in “DESIRED ACTION” of Boeing Multi Operator Message MOM-MOM-15-0248-01B, dated April 19, 2015; or Boeing Multi Operator Message MOM-MOM-15-0248-01B(R1), dated April 20, 2015. The main and auxiliary power unit (APU) batteries do not need to be disconnected when performing the electrical power deactivation. Repeat the electrical power deactivation thereafter at intervals not to exceed 120 days.

(1) Within 120 days after the last electrical power deactivation in accordance with step 2) in “DESIRED ACTION” of Boeing Multi Operator Message MOM-MOM-15-0248-01B, dated April 19, 2015; or Boeing Multi Operator Message MOM-MOM-15-0248-01B(R1), dated April 20, 2015.

(2) Within 120 days after the date of issuance of the original certificate of airworthiness or the date of issuance of the original export certificate of airworthiness.

(3) Within 7 days after the effective date of this AD.

Ok, great, great. As long as they remember to reboot the plane, we’ll be completely free from danger!


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