Boeing 737 Crash in China 2022_03_21

[southside]

Another possibility perhaps? Pilot lost his licence when this pic became viral.

This looks very fake to me? Photoshopped? The screens are weirdly blurred, the overhead panels look like a picture out of flight simulator.

Maybe I am wrong, just looks dodgy.

[GeraldNagel]

Just for you southside. I saw Santa Clause too but he was traveling at supersonic speed to deliver present to all little kids.

https://edition.cnn.com/travel/article/ ... index.html

[jimdavis]

Can someone tell me what the stall speed would be at 29000’ pls?
Hop

For 65,000kg flaps up maneuver speed is approximately 210 knots indicated (Vref 40 + 70) but this is for lower altitude, The actual stall speed will be around 180 to 190 KIAS. I can't find the high altitude buffet speeds, I'll keep looking.

At a particular weight and configuration, is the indicated stall speed not the same at all altitudes?

jim

[foxbat]

Can someone tell me what the stall speed would be at 29000’ pls?
Hop

For 65,000kg flaps up maneuver speed is approximately 210 knots indicated (Vref 40 + 70) but this is for lower altitude, The actual stall speed will be around 180 to 190 KIAS. I can't find the high altitude buffet speeds, I'll keep looking.

At a particular weight and configuration, is the indicated stall speed not the same at all altitudes?

jim

Only if you assume that air is incompressible

[Raffles]

Can someone tell me what the stall speed would be at 29000’ pls?
Hop

For 65,000kg flaps up maneuver speed is approximately 210 knots indicated (Vref 40 + 70) but this is for lower altitude, The actual stall speed will be around 180 to 190 KIAS. I can't find the high altitude buffet speeds, I'll keep looking.

At a particular weight and configuration, is the indicated stall speed not the same at all altitudes?

jim

Hello Jim,

The stall speed at high altitude ( > 20,0000 feet ) when flying at a high Mach number ( I guess > M0.5 ) will be higher due to compressibility effects. There is a fair explanation here

Use this link for more search results. https://searx.be/search?q=low+speed+buf ... ude+flight

I also use the NASA website a lot www.nasa.gov, if I can find the topic, I will share it with everyone here.

[Airwayfreak]

At a particular weight and configuration, is the indicated stall speed not the same at all altitudes?

jim

Stall speed increases due to compressibility.

PS: Sorry, I see Jim's question was answered

[jimdavis]

For 65,000kg flaps up maneuver speed is approximately 210 knots indicated (Vref 40 + 70) but this is for lower altitude, The actual stall speed will be around 180 to 190 KIAS. I can't find the high altitude buffet speeds, I'll keep looking.

At a particular weight and configuration, is the indicated stall speed not the same at all altitudes?

jim

Hello Jim,

The stall speed at high altitude ( > 20,0000 feet ) when flying at a high Mach number ( I guess > M0.5 ) will be higher due to compressibility effects. There is a fair explanation here

Use this link for more search results. https://searx.be/search?q=low+speed+buf ... ude+flight

I also use the NASA website a lot www.nasa.gov, if I can find the topic, I will share it with everyone here.

Okay thanks Raffles, got it. It seems the shock wave causes the wing to stall at a lower angle of attack, and thus a higher TAS and IAS.

jim

[wingnutzster]

I realize it's a little bit of a stretch but what about Mach Tuck? Mcrit for the 737NG series? The maximum authorized speed with Mach Trim inoperative is 0.74 Mach 480kts, the 'upset' here seems to have occurred dramatically and suddenly at around 450kts, mach trim failure? It's a rabbit hole because the discussion around Mcrit for the 737 is a long one with lots of maths and varying answers but is it at least plausible as something to tick off?

[MadMacs]

There have been many pressurization controller failures with the 737 and recently a Kalula B737 had to do an emergency decent into George, and as someone mentioned a controlled descent , it could have been an emergency descent gone wrong.

[Globemaster]

There is the Possibility of the aircraft being shot down by a missile. Could also explain the sudden dive.
The missiles would be heat seeking at close proximity and would then take out the wing…

[Christo]

There is the Possibility of the aircraft being shot down by a missile. Could also explain the sudden dive.
The missiles would be heat seeking at close proximity and would then take out the wing…

At that altitude it's out of range for an Igla/stinger. Would have to be a proper SAM system

[Morph]

There is the Possibility of the aircraft being shot down by a missile. Could also explain the sudden dive.
The missiles would be heat seeking at close proximity and would then take out the wing…

Would the aircraft not then dive in flames?

[Globemaster]

There is the Possibility of the aircraft being shot down by a missile. Could also explain the sudden dive.
The missiles would be heat seeking at close proximity and would then take out the wing…

Would the aircraft not then dive in flames?

Could well be, yes.
Another scenario could be a failure or seperation of the horizontal stabilizer. I hope they release the DFDR data so we can finally get closer to what happened.

[Pete]

There is the Possibility of the aircraft being shot down by a missile. Could also explain the sudden dive.
The missiles would be heat seeking at close proximity and would then take out the wing…

Would the aircraft not then dive in flames?

Could well be, yes.
Another scenario could be a failure or seperation of the horizontal stabilizer. I hope they release the DFDR data so we can finally get closer to what happened.

If the video is accurate, then:
1) there would not be flames, as the air speed would be way too high for combustion.
2) a horizontal stabilizer is required to maintain a vertical dive (if the wings are still attached) - without the stabilizer it would tumble.

[southside]

Just for you southside. I saw Santa Clause too but he was traveling at supersonic speed to deliver present to all little kids.

https://edition.cnn.com/travel/article/ ... index.html

It seems I was wrong. Thank you Gerald.