HarryMann
June 12, 2025, 10:24:00 GMT
permalink Post: 11899029

Quote:

Originally Posted by shared reality

Not familiar with the Dreamliner, but IF correct, it reportedly took off without backtracking, resulting in a TODA of app 1900m.. That sounds very marginal for a heavy 787 embarking on a 9+hr flight.
The horrifying video (IF legit) also suggests the aircraft is seriously on the backside of the power curve with gear down / flaps up..... Speculation: too early rotation due to rwy end approaching (too) fast-then mistakenly retracts flaps instead of raising the gear.... That would result in what we saw in the video... Pure speculation in this rumour network. A sad day indeed...

Looks like a tragic tragic lack of lift and thrust. PF seems to combat sink (or lack of climb rate) by simply pulling back nto deeper draggy stall.
Were flaps up at start of roll? or subsequently after marginal liftoff ? Unfamiliar with 787s interlocks and take-off protections but undercarriage should have been up.or going up in that state at a minimum

Subjects: None

HarryMann
June 12, 2025, 10:48:00 GMT
permalink Post: 11899052

Quote:

Originally Posted by JonnyH

Reports suggest, surprisingly, there are survivors. Fingers crossed.

looking at that fireball I\x92d suggest any survivors are not from the aircraft, but from the local population.

Subjects: None

HarryMann
June 13, 2025, 00:31:00 GMT
permalink Post: 11899866

Quote:

Originally Posted by CW247

That airport video shows an abrupt loss of lift with the aircraft pointing upwards the entire time which would explain (you know what). An engine failure would create some kind of yawing or change in pitch.

No, nothing abrupt, but a loss of thrust, yes?

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Engine Failure (All)

HarryMann
June 13, 2025, 23:13:00 GMT
permalink Post: 11900988

Quote:

Originally Posted by oxenos

Way back in the 60\x92s on the Shackleton, the time to 80 knots was calculated as an acceleration check. Never heard of any such check being used since then.

yes it was introduced/reintroduced by some airlines in the 70s I believe.

Subjects: None

HarryMann
June 14, 2025, 23:31:00 GMT
permalink Post: 11901956

Quote:

Originally Posted by overstress

An aerodynamic stall would do the same. And lay off the patronising, please.

it was clearly not a stalled situation though, until the last few seconds when the PF started a flare mameouve presumably to reduce vertical impact speed.

and with takeoff thrust you wouldn\x92t be stalling that aircraft in that config and situation easily.

no I relly don\x92t agree aerodynamic drag from a stalled wing is going to slow an aircraft with TO thrust by that much. nope.

Subjects: None

HarryMann
June 14, 2025, 23:38:00 GMT
permalink Post: 11901961

Quote:

Originally Posted by A320 Glider

Can I just clarify: the 787 has FBW and certain flight envelope protections. If the pilots suffered a dual engine failure after takeoff, they would pull back to stretch the glide as the computers will not allow the aircraft to stall. This is effectively what Sully did when he kissed it into the Hudson like a pro.

In any other aircraft, if you lose thrust in all your engines, you would be pushing the nose down immediately!

Dont follow that logic at all\x85 this flare in the last second or three wasn\x92t IMHO to stretch the glide but reduce vertical impact speed.
sully flared almost perfectly, nothing to do with \x91stretching\x92 the glide.

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Engine Failure (All) FBW

HarryMann
June 15, 2025, 08:32:00 GMT
permalink Post: 11902232

Quote:

Originally Posted by WITCHWAY550

My “problem” with sudden power loss is the video does not show a quick nose down as i think he would have done if all thrust has largely reduced.

I expect you (or most of us) reallly don’t know enough about the Flight Control Systems to say that. Any FBW intervention would have been in play and the Captain would notimmediately by instinct have lowered the nose dramatically, whilst assessing the situation… far too low and too much going on.

Last edited by HarryMann; 15th June 2025 at 08:50 .

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): FBW

HarryMann June 12, 2025, 10:24:00 GMT permalink Post: 11899029	Quote: Originally Posted by shared reality Not familiar with the Dreamliner, but IF correct, it reportedly took off without backtracking, resulting in a TODA of app 1900m.. That sounds very marginal for a heavy 787 embarking on a 9+hr flight. The horrifying video (IF legit) also suggests the aircraft is seriously on the backside of the power curve with gear down / flaps up..... Speculation: too early rotation due to rwy end approaching (too) fast-then mistakenly retracts flaps instead of raising the gear.... That would result in what we saw in the video... Pure speculation in this rumour network. A sad day indeed... Looks like a tragic tragic lack of lift and thrust. PF seems to combat sink (or lack of climb rate) by simply pulling back nto deeper draggy stall. Were flaps up at start of roll? or subsequently after marginal liftoff ? Unfamiliar with 787s interlocks and take-off protections but undercarriage should have been up.or going up in that state at a minimum Subjects: None
HarryMann June 12, 2025, 10:48:00 GMT permalink Post: 11899052	Quote: Originally Posted by JonnyH Reports suggest, surprisingly, there are survivors. Fingers crossed. looking at that fireball I\x92d suggest any survivors are not from the aircraft, but from the local population. Subjects: None
HarryMann June 13, 2025, 00:31:00 GMT permalink Post: 11899866	Quote: Originally Posted by CW247 That airport video shows an abrupt loss of lift with the aircraft pointing upwards the entire time which would explain (you know what). An engine failure would create some kind of yawing or change in pitch. No, nothing abrupt, but a loss of thrust, yes? Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Engine Failure (All)
HarryMann June 13, 2025, 23:13:00 GMT permalink Post: 11900988	Quote: Originally Posted by oxenos Way back in the 60\x92s on the Shackleton, the time to 80 knots was calculated as an acceleration check. Never heard of any such check being used since then. yes it was introduced/reintroduced by some airlines in the 70s I believe. Subjects: None
HarryMann June 14, 2025, 23:31:00 GMT permalink Post: 11901956	Quote: Originally Posted by overstress An aerodynamic stall would do the same. And lay off the patronising, please. it was clearly not a stalled situation though, until the last few seconds when the PF started a flare mameouve presumably to reduce vertical impact speed. and with takeoff thrust you wouldn\x92t be stalling that aircraft in that config and situation easily. no I relly don\x92t agree aerodynamic drag from a stalled wing is going to slow an aircraft with TO thrust by that much. nope. Subjects: None
HarryMann June 14, 2025, 23:38:00 GMT permalink Post: 11901961	Quote: Originally Posted by A320 Glider Can I just clarify: the 787 has FBW and certain flight envelope protections. If the pilots suffered a dual engine failure after takeoff, they would pull back to stretch the glide as the computers will not allow the aircraft to stall. This is effectively what Sully did when he kissed it into the Hudson like a pro. In any other aircraft, if you lose thrust in all your engines, you would be pushing the nose down immediately! Dont follow that logic at all\x85 this flare in the last second or three wasn\x92t IMHO to stretch the glide but reduce vertical impact speed. sully flared almost perfectly, nothing to do with \x91stretching\x92 the glide. Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Dual Engine Failure Engine Failure (All) FBW
HarryMann June 15, 2025, 08:32:00 GMT permalink Post: 11902232	Quote: Originally Posted by WITCHWAY550 My “problem” with sudden power loss is the video does not show a quick nose down as i think he would have done if all thrust has largely reduced. I expect you (or most of us) reallly don’t know enough about the Flight Control Systems to say that. Any FBW intervention would have been in play and the Captain would notimmediately by instinct have lowered the nose dramatically, whilst assessing the situation… far too low and too much going on. Last edited by HarryMann; 15th June 2025 at 08:50 . Subjects (links are to this post in the relevant subject page so that this post can be seen in context): FBW

Posts by user "HarryMann" [Posts: 7 Total up-votes: 0 Pages: 1]