B787 has a case of the drip
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Every airplane I've ever designed a part for has many many thousands of NAS1611 O-rings used in various places as sliding/rotating shaft seals in the hydraulic system.
But I suppose it really doesn't matter much in the end (aside from corrective action at the time).
Mildly humorous story about that incident - apparently there was an engineer type sitting near the #3 engine - he heard a bang and looked out the window and saw that the engine was gone! So he called a flight attendant over and said 'WE JUST LOST AN ENGINE' - the flight attendant started with the standard response that it's not uncommon to shut down an engine - the aircraft can still fly fine when the engineer stopped her and said 'NO! The engine is GONE' and pointed to the window. The FA looked out the window, gasped, and headed for the flight deck.
Meanwhile the pilots had gotten some warnings about the engine - pulled the fire handle and figured they were done. The FA came in an told them the engine was GONE - so the flight engineer went back and looked. Shocked, he returned to the flight deck and one of the pilots came back and looked...
Back in the flight deck, they decided the aircraft was still flying just fine, so they continued on to their destination...
I've come across plenty of hydraulic actuators in my career, just none with seals that were remotely O-shaped, but clearly I was wrong to rule out their existence.
I remember it a bit differently - I thought it was 'blue ice' from a leaking lav service pane
You're correct of course, Northwest Flight 5 report,
THE FORWARD LAVATORY EXTERNAL SEAL WAS MISSING THE SAFETY BUTTON AND THE INTERNAL SEAL WAS IMPROPERLY INSTALLED ALLOWING FOR LEAKAGE WHEN THE AIRPLANE WAS PRESSURIZED. THE FUSELAGE EXTERNAL SKIN AFT OF THE FORWARD LAVATORY SERVICE PANEL WAS STAINED WITH BLUE FLUID
I remember it a bit differently - I thought it was 'blue ice' from a leaking lav service panel.
But I suppose it really doesn't matter much in the end (aside from corrective action at the time).
Mildly humorous story about that incident - apparently there was an engineer type sitting near the #3 engine - he heard a bang and looked out the window and saw that the engine was gone! So he called a flight attendant over and said 'WE JUST LOST AN ENGINE' - the flight attendant started with the standard response that it's not uncommon to shut down an engine - the aircraft can still fly fine when the engineer stopped her and said 'NO! The engine is GONE' and pointed to the window. The FA looked out the window, gasped, and headed for the flight deck.
Meanwhile the pilots had gotten some warnings about the engine - pulled the fire handle and figured they were done. The FA came in an told them the engine was GONE - so the flight engineer went back and looked. Shocked, he returned to the flight deck and one of the pilots came back and looked...
Back in the flight deck, they decided the aircraft was still flying just fine, so they continued on to their destination...
But I suppose it really doesn't matter much in the end (aside from corrective action at the time).
Mildly humorous story about that incident - apparently there was an engineer type sitting near the #3 engine - he heard a bang and looked out the window and saw that the engine was gone! So he called a flight attendant over and said 'WE JUST LOST AN ENGINE' - the flight attendant started with the standard response that it's not uncommon to shut down an engine - the aircraft can still fly fine when the engineer stopped her and said 'NO! The engine is GONE' and pointed to the window. The FA looked out the window, gasped, and headed for the flight deck.
Meanwhile the pilots had gotten some warnings about the engine - pulled the fire handle and figured they were done. The FA came in an told them the engine was GONE - so the flight engineer went back and looked. Shocked, he returned to the flight deck and one of the pilots came back and looked...
Back in the flight deck, they decided the aircraft was still flying just fine, so they continued on to their destination...
With no engine driven hydraulic pump on the #3 engine it was the least worst one to drop
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The issue arises, when O-rings are being used in a presumed "static" situation and contamination of the sealing areas happens, then a "vibrating" static situation, will result in the contamination working itself into the sealing and leaking will start (including damaging the seal material itself). This is typically something to be expected, when the 2 sides of a seal are attached to different "fixed" mountings: The seal starts moving, the contamination works itself into the seal and the leaking starts.
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I remember it a bit differently - I thought it was 'blue ice' from a leaking lav service panel.
But I suppose it really doesn't matter much in the end (aside from corrective action at the time).
Mildly humorous story about that incident - apparently there was an engineer type sitting near the #3 engine - he heard a bang and looked out the window and saw that the engine was gone! So he called a flight attendant over and said 'WE JUST LOST AN ENGINE' - the flight attendant started with the standard response that it's not uncommon to shut down an engine - the aircraft can still fly fine when the engineer stopped her and said 'NO! The engine is GONE' and pointed to the window. The FA looked out the window, gasped, and headed for the flight deck.
Meanwhile the pilots had gotten some warnings about the engine - pulled the fire handle and figured they were done. The FA came in an told them the engine was GONE - so the flight engineer went back and looked. Shocked, he returned to the flight deck and one of the pilots came back and looked...
Back in the flight deck, they decided the aircraft was still flying just fine, so they continued on to their destination...
But I suppose it really doesn't matter much in the end (aside from corrective action at the time).
Mildly humorous story about that incident - apparently there was an engineer type sitting near the #3 engine - he heard a bang and looked out the window and saw that the engine was gone! So he called a flight attendant over and said 'WE JUST LOST AN ENGINE' - the flight attendant started with the standard response that it's not uncommon to shut down an engine - the aircraft can still fly fine when the engineer stopped her and said 'NO! The engine is GONE' and pointed to the window. The FA looked out the window, gasped, and headed for the flight deck.
Meanwhile the pilots had gotten some warnings about the engine - pulled the fire handle and figured they were done. The FA came in an told them the engine was GONE - so the flight engineer went back and looked. Shocked, he returned to the flight deck and one of the pilots came back and looked...
Back in the flight deck, they decided the aircraft was still flying just fine, so they continued on to their destination...
OF course there's this video of a waterfall on a BA A380:
https://www.dailymail.co.uk/news/art...-Heathrow.html
`
https://www.dailymail.co.uk/news/art...-Heathrow.html
`
BA said: 'There was no safety issue at any point, this was from the clean drinking water supply.
'The flight continued safely to Washington and landed as normal.
'The flight continued safely to Washington and landed as normal.
TD , isn't that why Boeing call it ''Engine , Fire , Severe damege , or Separation '' C/list/QRH ..
Does memory serve that an Hawaiian/Aloa ? 737-200 lost an engine when the backmost of 3 bolts holding it sheared , and said eng. departed over the top of the wing ?
rgds condor
Does memory serve that an Hawaiian/Aloa ? 737-200 lost an engine when the backmost of 3 bolts holding it sheared , and said eng. departed over the top of the wing ?
rgds condor
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TD , isn't that why Boeing call it ''Engine , Fire , Severe damege , or Separation '' C/list/QRH ..
Does memory serve that an Hawaiian/Aloa ? 737-200 lost an engine when the backmost of 3 bolts holding it sheared , and said eng. departed over the top of the wing ?
rgds condor
Does memory serve that an Hawaiian/Aloa ? 737-200 lost an engine when the backmost of 3 bolts holding it sheared , and said eng. departed over the top of the wing ?
rgds condor
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Perhaps getting mixed up with EL AL 1862?
https://en.wikipedia.org/wiki/El_Al_Flight_1862
https://en.wikipedia.org/wiki/El_Al_Flight_1862
The AA191 DC-10 accident comes closer, regarding loosing an engine "over the wing".
I certainly don't recall any 737 events where the engine departed the airframe. There of course where the two 747 events where the #3 engine fuse pin failed and as the engine departed it struck the #4 engine causing it to also depart - both freighters (not a complete coincidence). Not as many people know about the first event since only the crew was lost (plus, the engines were lost over the ocean and never recovered - we literally couldn't figure out how they could have lost two engines 'at once'). The El Al event unfortunately hit the apartment building resulting in high death toll, but the engines were found and recovered which revealed what had happened so the root cause could be corrected.
Not rated on the 73, and have no particular experience of them, however it appears that all the incidents involved the right or No.2 engine, and generally the initiating issue was with the 'aft cone bolt'. While it seems the root cause was mostly to do with poor maintenance (around installation of said bolt) I wonder why it would seem to only affect the right engine?
FP.
This brings memories of seeing the outcome of what was believed to be a cleaner's mop catching a pipe on a QANTAS A380.
QF94 was traveling from Los Angeles to Melbourne when a water pipe became detached, flooding the upper deck and causing waterfalls onto those on the lower deck. It struck a chord with me as I was doing galley certification at the time and had raised a concern about an oversize waste water hose which would not seal. After emailing the photos of the A380 flood to our quality department, they told me I was being alarmist.
The Aviation Herald - A380 Cabin flood, QF94 2 July 2014
QF94 was traveling from Los Angeles to Melbourne when a water pipe became detached, flooding the upper deck and causing waterfalls onto those on the lower deck. It struck a chord with me as I was doing galley certification at the time and had raised a concern about an oversize waste water hose which would not seal. After emailing the photos of the A380 flood to our quality department, they told me I was being alarmist.
The Aviation Herald - A380 Cabin flood, QF94 2 July 2014
Yes, from what I read that's correct, although I must reiterate my lack of actual experience here.
Another common factor in the five incidents noted was that the failure occurred at the takeoff/climb phase of flight. I have no concept of how the engine mounting is designed but can imagine that's generally when the most load is likely to be applied to the fixings, so hardly surprising.
I guess the takehome from this is that if you're a 73 driver in the climb and your machine starts yawing to the right (and maybe the throttles retard), have a squiz out the RHS window to see if you need to issue a hard hat warning for those on the ground
And if you're a mech, take great care to install said cone bolt per the approved methodology.
FP.
Another common factor in the five incidents noted was that the failure occurred at the takeoff/climb phase of flight. I have no concept of how the engine mounting is designed but can imagine that's generally when the most load is likely to be applied to the fixings, so hardly surprising.
I guess the takehome from this is that if you're a 73 driver in the climb and your machine starts yawing to the right (and maybe the throttles retard), have a squiz out the RHS window to see if you need to issue a hard hat warning for those on the ground
And if you're a mech, take great care to install said cone bolt per the approved methodology.FP.
