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Vietnam 787 No gear down
Surprised, this has not been mentioned before.
How can a 787 get to (alleged) 650ft and not realise gear not down? https://simpleflying.com/vietnam-air...g-787-gear-up/ Have I missed something on this story? |
They would have realised by the warning systems in place , whether that prompted action we don’t know |
Prompted by ATC
https://www.atsb.gov.au/publications...r/ao-2019-051/ |
The gear warning comes on at 800 feet AGL off the radar altimeter in the 787. Probably got the warning about the same time ATC was calling. |
Originally Posted by Sailvi767
(Post 10574720)
The gear warning comes on at 800 feet AGL off the radar altimeter in the 787. Probably got the warning about the same time ATC was calling. |
Originally Posted by Sailvi767
(Post 10574720)
The gear warning comes on at 800 feet AGL off the radar altimeter in the 787. Probably got the warning about the same time ATC was calling. |
Originally Posted by roundsounds
(Post 10574789)
Melbourne is 400’ AMSL, FR24 data shows 650’ making it around 250’ AGL at the GA?
Given that it corresponded to at a point 1.6 nm from the THR, then I suspect they weren't actually at 250' AGL. |
FR24 displays Altitude based on Standard Pressure. If there is a large difference between that and the local QNH, you will need to apply the difference to see the real altitude. I recall the local QNH at the time was 1027mb. That’s a 420 feet adjustment. |
Plus crew reaction time |
What is the terrain like on the approach? If it slopes upwards towards the runway, then 800ft on the radio altimeter may be low in reference to the runway threshold.
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Originally Posted by Capt Fathom
(Post 10574827)
FR24 displays Altitude based on Standard Pressure. If there is a large difference between that and the local QNH, you will need to apply the difference to see the real altitude.
I recall the local QNH at the time was 1027mb. That’s a 420 feet adjustment. So that would make the altitudes at the initiation of the GA (approximately): Mode C/Mode S: 650' AMSL: 1050' AAL: 625' Rad Alt/AGL: obviously dependent on terrain (if anyone with local knowledge can help, it was 1.6 nm from the THR, roughly overhead the Keilor Stadium) |
Originally Posted by DaveReidUK
(Post 10575040)
So that would make the altitudes at the initiation of the GA (approximately):
Mode C/Mode S: 650' AMSL: 1050' AAL: 625' Rad Alt/AGL: obviously dependent on terrain (if anyone with local knowledge can help, it was 1.6 nm from the THR, roughly overhead the Keilor Stadium) |
On the Boeing 777 you would get a config warning if you select land flap and the the gear is not down, so the warning would come at about 1500 AGL. I wonder why the logic is different on the 787. |
Originally Posted by suninmyeyes
(Post 10575148)
On the Boeing 777 you would get a config warning if you select land flap and the the gear is not down, so the warning would come at about 1500 AGL. I wonder why the logic is different on the 787. |
Originally Posted by suninmyeyes
(Post 10575148)
On the Boeing 777 you would get a config warning if you select land flap and the the gear is not down, so the warning would come at about 1500 AGL. I wonder why the logic is different on the 787. A landing gear is not down and locked and one of these occurs:
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I’m sure they have a gear warning when you select landing flap without gear down as well, same as the 737. That will happen much earlier. |
Originally Posted by suninmyeyes
(Post 10575148)
On the Boeing 777 you would get a config warning if you select land flap and the the gear is not down, so the warning would come at about 1500 AGL. I wonder why the logic is different on the 787. |
In the old days it would be called a low drag approach. Saves fuel. Left the gear down selection a bit late, that's all..
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Strange
To me this whole situation seems really strange, either the plane was not configured for landing, or the bells& whistles did not work. Alternatively the twr was wrong |
Originally Posted by Capt Fathom
(Post 10574827)
FR24 displays Altitude based on Standard Pressure. If there is a large difference between that and the local QNH, you will need to apply the difference to see the real altitude. I recall the local QNH at the time was 1027mb. That’s a 420 feet adjustment. |
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