Unusual Cracks Found on Two American Airlines 767s

Titlu: Unusual Cracks Found on Two American Airlines 767s
Sursa: http://nycaviation.com/2010/06/22/unusual-cracks-found-on-two-american-airlines-767s/
Autor: Jeremy Lindgren
Data: 22.06.2010

Citat :

Structural cracks recently found on the engine pylons of three American Airlines 767 airliners are prompting concerns that a more widespread problem may be afoot.

Over the past two weeks American Airlines mechanics, along with the FAA, have been vigorously inspecting their entire fleet of 73 Boeing 767’s for the newfound cracks. The FAA reports that only three have so far turned up with cracking, with one aircraft reportedly so badly damaged that air-safety regulators believe the engine could have easily separated from the plane. American, however, told the Wall Street Journal that two—not three—aircraft were found with the pylon-related cracks, and that the problems “were caught when they should have been.” American added that tests so far on the metal have yet to come back, leaving any speculation on the cause of the issue to be “a guess at best.”

In the meantime, Boeing has been working on drafting a service bulletin that is expected to recommend significantly stepped-up inspections by the vast majority of 767 operators worldwide. The 767 is already subject to fairly strict inspection requirements (every 1,500 flights) for a number of engine pylon components, meaning these cracks have developed in a relatively short period of time. American and the FAA both agree that the safety concerns are not a product of missed or substandard inspections, but rather that these cracks were an unexpected development. The FAA in expected to adopt most of Boeing’s recommendations, which will be enforced on all of the roughly 360 767’s currently operating with US carriers.

American Airlines currently operates 73 Boeing 767 aircraft; 15 -200 models and 58 -300 models. They have operated, at one point or another, a total of 97 of them, with only two being written off. They took delivery of their first aircraft in 1982, and have used the planes on a mix of trans-continental and inter-continental routes throughout their tenure.

The 767 took its first flight in September of 1981. Since then just under one thousand have been built, with about 850 frames currently in service worldwide.