Erebus wrote:

QF 32 is probably one of the more high profile ones in recent times, the cause being a misaligned counter bore within a stub oil pipe leading to a fatigue fracture.

klm617 wrote:

Japan Airlines 123

klm617 wrote:

Japan Airlines 123

klm617 wrote:

The Comet

klm617 wrote:

Turkish 981, American 191 and American 96

klm617 wrote:

Japan Airlines 123

klm617 wrote:

The Comet

Erebus wrote:

QF 32 is probably one of the more high profile ones in recent times, the cause being a misaligned counter bore within a stub oil pipe leading to a fatigue fracture.

stephanwintner wrote:

Erebus wrote:

QF 32 is probably one of the more high profile ones in recent times, the cause being a misaligned counter bore within a stub oil pipe leading to a fatigue fracture.

If I recall, it was either that the blueprint did not specify a concentricity between the two relevant diameters, so the thin wall was not detected, or that the blueprint tolerance was met, but that specified tolerance was too much, and permitted a very thin wall, which cracked. Either way, I think the part met the blueprint.... kinda scary.

fabian9 wrote:

Erebus wrote:

QF 32 is probably one of the more high profile ones in recent times, the cause being a misaligned counter bore within a stub oil pipe leading to a fatigue fracture.

I don’t remember if the engineering drawing of the part was missing a concentricity tolerance berween the pipe and the counterbore? If it did, then this would be considered an engineering drop off rather than manufacturing?

stephanwintner wrote:

Erebus wrote:

QF 32 is probably one of the more high profile ones in recent times, the cause being a misaligned counter bore within a stub oil pipe leading to a fatigue fracture.

If I recall, it was either that the blueprint did not specify a concentricity between the two relevant diameters, so the thin wall was not detected, or that the blueprint tolerance was met, but that specified tolerance was too much, and permitted a very thin wall, which cracked. Either way, I think the part met the blueprint.... kinda scary.

Beat me to it.

SteelChair wrote:

I seem to remember a whole series of Boeing twins that had the cables for the T handles reversed in the 1990s.

CALTECH wrote:

SteelChair wrote:

I seem to remember a whole series of Boeing twins that had the cables for the T handles reversed in the 1990s.

Nope. Pilot error. British Midland. They shut down the good engine. Though IIRC, there was vibrations in the upgraded engines which were not accounted for, could be called a manufacturing defect or testing defect. Fan blade broke. Precautionary inspections were carried out in Fleet Campaign Directives to inspect T-Handles and Fire Bottles, which turned up nothing. And T Handles have no cables, wires, but not cables.

SteelChair wrote:

CALTECH wrote:

SteelChair wrote:

I seem to remember a whole series of Boeing twins that had the cables for the T handles reversed in the 1990s.

Nope. Pilot error. British Midland. They shut down the good engine. Though IIRC, there was vibrations in the upgraded engines which were not accounted for, could be called a manufacturing defect or testing defect. Fan blade broke. Precautionary inspections were carried out in Fleet Campaign Directives to inspect T-Handles and Fire Bottles, which turned up nothing. And T Handles have no cables, wires, but not cables.

That is not the incident to which I was referring.

And many airplanes have cables to the firewall valves (fuel and hydraulic) though on every airplane that I am aware of the squibs are fired electrically.

Noshow wrote:

Swissair MD-11 at Halifax.
Not original MDD manufacturing related but happened during heavy maintenance later:
Had received some aftermarket IFE that accidentally got hooked up to the hot battery bus. Crew had no chance to pull the circuit breakers when facing some electrical fire and crashed.

The probable cause of the accident was determined to be the failure of the propeller due to undiscovered metal fatigue in one blade resulting from corrosion from chlorine.[1]:v There had been two previous failures of the same type of propeller, but those aircraft had been able to land safely.[1]:26–27 The failed propeller blade had undergone scheduled ultrasonic testing on May 19, 1994, which resulted in its rejection and removal from the propeller.[1]:37 The blade was sent to a Hamilton Standard facility, where it was subject to refurbishing work that was incorrectly performed.[1]:v The propeller blade was then installed on the propeller fitted to the aircraft on September 30, 1994.[1]:39

The National Transportation Safety Board (NTSB) criticized Hamilton Standard, who had maintained the propellers, for "inadequate and ineffective corporate inspection and repair techniques, training, documentation and communication", and both Hamilton and the Federal Aviation Administration for "failure to require recurrent on-wing ultrasonic inspections for the affected propellers".[1]:v The overcast skies and low cloud ceiling at the crash site also contributed to the severity of the crash.[1]:v