#2 2014-03-01 08:11:19
Beware the promise of the plane (or car) that can always fly itself better than what we had before.
In the real world we are only as good as the electronic diagnostic system we design. That goes doubly for the instructions we require of the monkeys who maintain what we bet our sweet asses upon.
These fockers disconnected the working airspeed system. Because their service manual checklist required them to just swap the data processors before applying themselves to another logical fix.
...the takeoff was rejected however due to an airspeed disagree at the 80 knots call with the captain's airspeed having failed.
Maintenance subsequently swapped ADIRU1 and ADIRU2, switched the first officer's instruments to ADIRU3 with the captain's instruments connected to ADIRU1, and dispatched the aircraft under minimum equipment list requirements with ADIRU2 set to inoperative.
The aircraft taxied out again and initiated the takeoff roll, after the aircraft had accelerated beyond V1 the crew again noticed an airspeed disagree, continued takeoff, declared emergency and returned to Brisbane for a safe landing.
Subsequent engineering inspection detected that the captain's pitot probe was obstructed, the probe was removed from the aircraft and sent for further analysis. The manufacturer found that the probe had been almost completely blocked by a wasp nest composed of sand and mud consistent with nests of "mud-dauber wasps". The investigation continues.
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#3 2014-03-01 19:01:13
The comments note that each ADIRU is just a processing unit. The implication of the narrative seems to be that none of them were actually defective, so swapping them around really had no effect at all.
The problem was the blockage of the pitot tube, which would intermittently send faulty signals to whichever ADIRU it was connected to. Because the problem seemed to stop when the ADIRUs were swapped, maintenance assumed they had a defective ADIRU and didn't investigate further.
One might consider this to be unacceptable, but without knowing all the details, it's hard to say. If you were to chase down and inspect everything that could affect indicated airspeed, it's likely that in all but a tiny number of cases, you'd be inspecting the pitot tubes and other components and find them completely fine, wasting hours chasing a non-existent problem.
My question is, how long were the pitot tubes left uncovered such that the wasps would be able to bring in so much mud?
On a related note, saving Columbia (or not).
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#4 2014-03-01 19:09:35
An Etihad Boeing 777-300, registration A6-ETM performing flight EY-461 from Melbourne,VI (Australia) to Abu Dhabi (United Arab Emirates), was enroute over the Indian Ocean west of Australia when the fire detectors in a lavatory in economy class triggered alarm. Smoke and flames were visible from a bin in the lavatory, cabin crew quickly extinguished and contained the small fire. About 2 hours later the fire detector of another lavatory in the economy class triggered alarm, again cabin crew needed to extinguish a small fire in the bin of that lavatory. The captain decided to divert the aircraft to Jakarta (Indonesia) where the aircraft landed safely, all passengers disembarked and were questioned by Indonesian police.
The aircraft continued the flight after about 4 hours on the ground with all passengers aboard and reached Abu Dhabi with a delay of 4:15 hours, however, not without three more fire incidents after which the captain ordered cabin crew to stop all cabin service and guard the lavatories instead until landing in Abu Dhabi.
...
Passengers were upset about the flight being continued without the arsonist being identified and removed from the flight. Gossip amongst passengers indicated a female had set the lavatories alight.
On Feb 20th 2014 the airline reported that the 12 detained passengers were all released again, as there was no conclusive evidence. There had been two fire incidents after takeoff resulting in the diversion to Jakarta, three more fire incidents occurred while enroute from Jakarta to Abu Dhabi.
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#5 2014-05-25 02:46:02
Air traffic control puts two airliners on a collision course -- disaster was only averted when a TCAS warning prompted one to suddenly dive at least 600 feet.
A first-person perspective, with follow-up:
I was weightless. We all were. Thirty-three thousand feet up in a cloudless sky, our plane had suddenly pitched into a steep dive. I felt my body float upwards and strain against my seatbelt. Passengers around me screamed. There was a loud crash in the back -- a coffeepot clattering to the floor and tumbling down the aisle. Our tray tables began rattling in unison as the 757 strained through the kind of maneuver meant more for a fighter jet. Top Gun this was not, though. Our flight that Friday, April 25th, was mostly heavy-set tourists returning to California from Hawaii. More Tommy Bahama than Tom Cruise.
Weightless and staring downhill at the thirty-some rows of passengers ahead of me, I had a rare and terrible reminder of the absurd improbability of human flight. We were hairless apes crowded into a thin metal tube hurtling through the sky at a speed and height beyond anything evolution prepared us to comprehend. The violence was over after a few seconds. United 1205 leveled out, having dropped at least 600 feet without warning. . . .
On Friday, two weeks after the near miss and my initial call with the FAA, I followed up with the agency and learned that the Air Traffic Organization (ATO) was looking into the incident. According to the FAA official I spoke with, the sheer fact that they’re exploring the event implied to him that they saw it as "significant," even though they’d never passed it on to the FAA with any formal categorization. Two weeks of daily ATO reports to the FAA had gone by without a mention of this likely "significant" event. This official took issue with ATO not sharing the event, but admitted that there is no requirement for sharing, only common practice.
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#6 2014-05-25 04:05:09
Auto-edited on 2020-08-02 to update URLs
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