B-737 Cargo Plane down in Hawaii
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Sully's wasn't gentle either. As against recommended ditching of minimum VS, Sully landed around 740ft/mt. That's because of the time pressure his speed went19kts below recommended Vapp and due to activation of airbus alpha (low speed) protection was unable to flare sufficiently. That's why aircraft was written off.
Last edited by vilas; 5th Nov 2021 at 12:26.
Only half a speed-brake
I see TE flaps in, or almost so.
Imagine a crew trying to make a field with insufficient thrust, understandably they'd be keeping clean conf. and speed for max L/D. On the other hand, a pre-determined ditching is surely flown at the slowest Vref you could get.
Estimating 210 and 130 kts for the two cases, with an impact weight of 49 t,
the kinetic energy equation gives 270 MJ and 104 MJ respectively.
No need to look any further why the same metal buckles and bends once but breaks and tears on a different day.
The involuntary ditchings discussed above were all at approach speed, to my understanding.
Imagine a crew trying to make a field with insufficient thrust, understandably they'd be keeping clean conf. and speed for max L/D. On the other hand, a pre-determined ditching is surely flown at the slowest Vref you could get.
Estimating 210 and 130 kts for the two cases, with an impact weight of 49 t,
the kinetic energy equation gives 270 MJ and 104 MJ respectively.
No need to look any further why the same metal buckles and bends once but breaks and tears on a different day.
The involuntary ditchings discussed above were all at approach speed, to my understanding.
Last edited by FlightDetent; 6th Nov 2021 at 18:36.
Updated report from NTSB is suggesting a human factors accident.
Crew misidentified the dead engine. Crew reported they had lost #1 engine.
https://data.ntsb.gov/Docket/Documen...Docket-Rel.pdf
Crew misidentified the dead engine. Crew reported they had lost #1 engine.
https://data.ntsb.gov/Docket/Documen...Docket-Rel.pdf
As the aircraft passed through about 390 ft at 155 knots, engine 2 EPR suddenly dropped to 1.43, while engine 1 remained at its previously set takeoff power. Immediately after engine 2 EPR dropped, the rudder pedal moved to about 5.5 degrees of left rudder, consistent with a command to counteract the adverse yaw of losing thrust on the right engine. The climb paused at 1,000 feet for 25 seconds, then continued to 2,000 ft.
At 2,000 feet, engine 1 EPR reduced to a value of 1.051, which is consistent with idle power in previous flights. It stayed at this value for the remainder of the flight.
Engine 2 EPR also reduced at 2,000 feet, however it continued to be advanced and reduced several times until the end of the flight.
Altitude and airspeed decreased over the next 9 minutes until the end of the recording. At the end of the recording, engine 2 EPR was 1.462 and engine 1 EPR, having been stable since it reduced at 2,000 feet, was still consistent with previous flight idle settings at 1.052.
At 2,000 feet, engine 1 EPR reduced to a value of 1.051, which is consistent with idle power in previous flights. It stayed at this value for the remainder of the flight.
Engine 2 EPR also reduced at 2,000 feet, however it continued to be advanced and reduced several times until the end of the flight.
Altitude and airspeed decreased over the next 9 minutes until the end of the recording. At the end of the recording, engine 2 EPR was 1.462 and engine 1 EPR, having been stable since it reduced at 2,000 feet, was still consistent with previous flight idle settings at 1.052.
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Last edited by punkalouver; 21st Dec 2022 at 15:18.
“As the aircraft passed through about 390 ft at 155 knots, engine 2 EPR suddenly dropped to 1.43, while engine 1 remained at its previously set takeoff power. Immediately after engine 2 EPR dropped, the rudder pedal moved to about 5.5 degrees of left rudder, consistent with a command to counteract the adverse yaw of losing thrust on the right engine. The climb paused at 1,000 feet for 25 seconds, then continued to 2,000 ft.
I am reminded of the Kegworth 737 crash where the good engine was also shut down.
Excerpt from the 2nd captain interview. Epiphany?
Oh, if the number 1 engine is gone, it's not only the EPR. Then you'll get backup information. It's not going to be only from Greg [FO]. You're going to get backup indication to confirm that number 1 is gone. But we didn't get there. We didn't, we didn't get there. You know, right now I think, as I'm sitting here and you're asking me about number 1 thrust lever, number 1 -- number 1, I'm beginning to wonder did we shut down the wrong engine, you know? Because I don't know.
Oh, if the number 1 engine is gone, it's not only the EPR. Then you'll get backup information. It's not going to be only from Greg [FO]. You're going to get backup indication to confirm that number 1 is gone. But we didn't get there. We didn't, we didn't get there. You know, right now I think, as I'm sitting here and you're asking me about number 1 thrust lever, number 1 -- number 1, I'm beginning to wonder did we shut down the wrong engine, you know? Because I don't know.
Is this going to have any imapct on the 737 Max-10 debacle (not that I understand it even vaguely well enough), but isn't the issue they're trying for the ability ignore the mandate on EICAS implementation. I'm an Airbus guy, ECAM or equivalent have identified this far better, certainly far more methodically?
Last edited by giggitygiggity; 22nd Dec 2022 at 01:07.
Only half a speed-brake
There has been a case on Airbus where N1/N2 vibration was mistaken for left/right engine designation. Just because of the digit (while squarely showing on-side where the problem actually was).
Engineering HF mistakes out is understandable, but to which extent is it justified?
Engineering HF mistakes out is understandable, but to which extent is it justified?
Is this going to have any imapct on the 737 Max-10 debacle (not that I understand it even vaguely well enough), but isn't the issue they're trying for the ability ignore the mandate on EICAS implementation. I'm an Airbus guy, ECAM or equivalent have identified this far better, certainly far more methodically?
Unintended consequences can be a bitch...
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Actually, the Kegworth disaster would suggest that changing the flight deck from what the crews are used to might be a bad idea. One of the contributing factors in Kegworth was that on the 737-400 (and -300 IIRC) they'd changed the vibration displays relative to the -200 that they crew was used to. That contributed to the crew miss-identifying the bad engine.
Unintended consequences can be a bitch...
Unintended consequences can be a bitch...
It looks like this case is a perfectly good engine that was brought to idle but was still running, and in a position to be immediately used but assumed to be faulty and left at idle. From a procedure point of view, one wonders why they didn't take the time to shut it down if they thought it was faulty. Quite odd.
But on the other hand, seeing as they didn't follow typical procedures and shut down what they thought was a faulty engine, their atypical procedure left them with a big advantage........the ability to use the engine at idle, regardless of whether it was faulty or not. It appears that they thought they had two bad engines. But why would you not attempt to use that engine as things get worse and worse with the GPWS sounding and the altitude and speed decreasing. It would seem that it was assumed that because the engine at idle was in poor shape, it was never considered but one should definitely have in mind that they will take whatever they can get from what is assumed to be a bad engine as it could prevent a crash. Get what you can from both of them in such a situation(and in this case, they would have gotten a bunch of thrust from when they thought they wouldn't get much).
Last edited by punkalouver; 23rd Dec 2022 at 01:52.
Actually, the Kegworth disaster would suggest that changing the flight deck from what the crews are used to might be a bad idea
Report
https://assets.digital.cabinet-offic...990_G-OBME.pdf
Commentary on panel layout
https://assets.digital.cabinet-offic...BME_Append.pdf
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Quotes(in black) from a Flight International article based on NTSB information.....
"The first officer, who was flying, replied “number two” – an apparent reference to the right-hand powerplant – and the captain also said, “number two”.
According to the quote above, the captain repeated what the F/O said(unknown if he based his reply on separate analysis). Then according to the quote below, the copilot changed his mind and the captain did as well(unknown what further assessment was made by the captain before he changed his mind).
"According to the transcript, the captain asked the first officer to “read the gauges” to determine which “has the EGT” – the exhaust gas temperature – to which the first officer replied: “It looks like the number one.”The captain then responded, “Number one is gone?”, and the first officer responded: “[It’s] gone, yep…so we have number two.”
“So we have number two, OK,” the captain then remarked."
The captain made this statement to the inquiry.....
"The captain told the inquiry that he thought the left-hand engine had the problem, at first, before changing his mind – based on the aircraft’s yaw and roll motion – and telling the first officer that he thought the right-hand engine was the one affected.
But during his testimony the captain referred to the first officer’s having told him that the number one engine, the left-hand powerplant, had failed.
The captain told investigators that the first officer, which whom he had flown several times, “never makes a mistake”, adding: “If [he] says number one is gone, then number one is gone.”
A bit of a conflict in statements but quite the trusting captain. Based on the CVR recording, it seems quite possible that the captain did change his mind based on what the F/O said, instead of analyzing the problem.
This reminds me of the Kegworth accident when it comes to failed engine identification. To quote the report.....
"The first officer also said that he monitored the engine instruments and, when asked by the commander which engine was causing the trouble, he said 'IT'S THE LE ... IT'S THE RIGHT ONE.', to which the commander responded by saying 'OKAY, THROTTLE IT BACK'."
Once again, no detail on what analysis that captain did, but it does give one the feeling that he may have relied on what the copilot said instead of confirming himself(captain was flying). One really should take extra time to identify a partial engine failure, if time permits. the consequences of a mis-identification can be catastrophic. In addition, a partial failure may not be obvious after thrust has been reduced.
"The first officer, who was flying, replied “number two” – an apparent reference to the right-hand powerplant – and the captain also said, “number two”.
According to the quote above, the captain repeated what the F/O said(unknown if he based his reply on separate analysis). Then according to the quote below, the copilot changed his mind and the captain did as well(unknown what further assessment was made by the captain before he changed his mind).
"According to the transcript, the captain asked the first officer to “read the gauges” to determine which “has the EGT” – the exhaust gas temperature – to which the first officer replied: “It looks like the number one.”The captain then responded, “Number one is gone?”, and the first officer responded: “[It’s] gone, yep…so we have number two.”
“So we have number two, OK,” the captain then remarked."
The captain made this statement to the inquiry.....
"The captain told the inquiry that he thought the left-hand engine had the problem, at first, before changing his mind – based on the aircraft’s yaw and roll motion – and telling the first officer that he thought the right-hand engine was the one affected.
But during his testimony the captain referred to the first officer’s having told him that the number one engine, the left-hand powerplant, had failed.
The captain told investigators that the first officer, which whom he had flown several times, “never makes a mistake”, adding: “If [he] says number one is gone, then number one is gone.”
A bit of a conflict in statements but quite the trusting captain. Based on the CVR recording, it seems quite possible that the captain did change his mind based on what the F/O said, instead of analyzing the problem.
This reminds me of the Kegworth accident when it comes to failed engine identification. To quote the report.....
"The first officer also said that he monitored the engine instruments and, when asked by the commander which engine was causing the trouble, he said 'IT'S THE LE ... IT'S THE RIGHT ONE.', to which the commander responded by saying 'OKAY, THROTTLE IT BACK'."
Once again, no detail on what analysis that captain did, but it does give one the feeling that he may have relied on what the copilot said instead of confirming himself(captain was flying). One really should take extra time to identify a partial engine failure, if time permits. the consequences of a mis-identification can be catastrophic. In addition, a partial failure may not be obvious after thrust has been reduced.
Last edited by punkalouver; 24th Dec 2022 at 23:41.
Only half a speed-brake
My type has a TL indication, commanded EPR target if you will. Already rated a few years when I copied someone's technique to visually observe how that doughnut moves - on the dead engine - as I pull the TL back to idle.
And later added an extra eyeflow myself, to confirm what the remaining good engine is doing AFTER closing the TL, i.e. BEFORE taking the next step of selecting the master switch/fuel shutoff. Which is a pretty universal tool technique.
Once this became a habit, I get stunned at how little is being actually checked by colleagues in the SIM who do the same as I used to (admittedly we always got it correct).
And later added an extra eyeflow myself, to confirm what the remaining good engine is doing AFTER closing the TL, i.e. BEFORE taking the next step of selecting the master switch/fuel shutoff. Which is a pretty universal tool technique.
Once this became a habit, I get stunned at how little is being actually checked by colleagues in the SIM who do the same as I used to (admittedly we always got it correct).
Last edited by FlightDetent; 25th Dec 2022 at 13:37.
Quotes(in black) from a Flight International article based on NTSB information.....
"The first officer, who was flying, replied “number two” – an apparent reference to the right-hand powerplant – and the captain also said, “number two”.
According to the quote above, the captain repeated what the F/O said(unknown if he based his reply on separate analysis). Then according to the quote below, the copilot changed his mind and the captain did as well(unknown what further assessment was made by the captain before he changed his mind).
SNAP......
Once again, no detail on what analysis that captain did, but it does give one the feeling that he may have relied on what the copilot said instead of confirming himself(captain was flying). One really should take extra time to identify a partial engine failure, if time permits. the consequences of a mis-identification can be catastrophic. In addition, a partial failure may not be obvious after thrust has been reduced.
"The first officer, who was flying, replied “number two” – an apparent reference to the right-hand powerplant – and the captain also said, “number two”.
According to the quote above, the captain repeated what the F/O said(unknown if he based his reply on separate analysis). Then according to the quote below, the copilot changed his mind and the captain did as well(unknown what further assessment was made by the captain before he changed his mind).
SNAP......
Once again, no detail on what analysis that captain did, but it does give one the feeling that he may have relied on what the copilot said instead of confirming himself(captain was flying). One really should take extra time to identify a partial engine failure, if time permits. the consequences of a mis-identification can be catastrophic. In addition, a partial failure may not be obvious after thrust has been reduced.
I think, the more the "actions" are physical, the more people are inclined to take things for granted and leave out the "logic" items, since that does require a change in mental attention, from the steam gauges and levers attention, over to check-list booklets. With the whole being more "push-button" oriented, it needs mental attention to what the meaning of the buttons is, and the drivers are already in that mental state to "think" what they are doing.