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Air India flight to London crashes in Ahmedabad with more than 240 onboard

theguardian.com

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Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#571

Post by wkat4242 »

mdavidn wrote: post #168
ikekkdcjkfke wrote: post #146

Earlier quoted context omitted.

Well, loss of engine power and gliding to a stop is not that a far fetched case. Why is there not a fuel dump button to prevent a whole trips worth of fuel going up in flames?

There is, but dumping takes time, and it’s not done over populated areas. It would be low on the pilots’ checklist in an emergency.

Yes and smaller airliners don't have it. As I understand it, it's for the widebodies because they often have a higher maximum takeoff weight than maximum landing weight. Meaning that if they just took off and need to return right away they have a big problem. Because they're too heavy to land.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#572

Post by wkat4242 »

iamtheworstdev wrote: post #164
ikekkdcjkfke wrote: post #146

Earlier quoted context omitted.

Well, loss of engine power and gliding to a stop is not that a far fetched case. Why is there not a fuel dump button to prevent a whole trips worth of fuel going up in flames?

because painting an entire neighborhood in flammable fluid isn't safe... if it doesn't catch fire it'll corrode everything it touches. most planes can't dump fuel anymore. if it's a serious enough emergency you land overweight. If it's not then you fly long enough to burn it off and land below max landing weight.

It won't corrode I don't think. It's just oil, it's not petrol like in small airplanes.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#573

Post by wkat4242 »

fredoralive wrote: post #127
mattbrewsbytes wrote: post #63

Earlier quoted context omitted.

I was just watching something the other day about how jet engines have gotten more efficient and powerful over the last 50 years where commercial airliners really only need 2 engines. All 2 engine aircraft also have to be able to operate on 1 engine as well if there is a failure. One has to wonder if this was a bird strike incident on both engines that maybe having 4 engines would have allowed the plane to circle bac…

In the 1980s a British Airways 747 flew through volcanic ash and lost all four engines. So just having more engines may not always be the solution, as in suitably unlikely circumstances you can still lose all of them. (In that case they were at cruising altitude, so had time to handle the situation and relight the engines).

Wow they were lucky to be able to relight them with the engines full of glass.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#574

Post by wkat4242 »

ho_schi wrote: post #367
fredoralive wrote: post #127

Earlier quoted context omitted.

In the 1980s a British Airways 747 flew through volcanic ash and lost all four engines. So just having more engines may not always be the solution, as in suitably unlikely circumstances you can still lose all of them. (In that case they were at cruising altitude, so had time to handle the situation and relight the engines).

It depends on the situation. Redundancy and additional power increase margins. More for the sake of more isn't necessary helping. https://www.youtube.com/watch?v=z_ewa7R20MA Lufthansa 747-8 after engine failure: *We're not an emergency.* It depends on what is causing the failure and how situation evolves. Let us take British Airways Flight 009 as example, the wiki says that all engines failed, all engines were restar…

> Emirates needs the huge capacities of the A380.

I think it's more that they needed the prestige of having the biggest planes, offering a whole bedroom with shower etc. It goes well with their ultra luxury image.

If it's just about seats that can fly smaller ones with the benefit that they can operate more frequently and thus attract more transit passengers looking for a good connection. That's their main market.

An A380 is quite a hassle because most airports can't even handle one.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#575

Post by wkat4242 »

bartread wrote: post #84
defrost wrote: post #71

Earlier quoted context omitted.

A multiple engine aircraft maintaining flight on a single engine is vastly different to the same craft being able to complete a take off when an engine fails mid process. Aircraft can land (in right circumstances) by gliding in sans power .. the same cannot be said for take offs.

If during your takeoff roll you lose one engine on a twin engine jet below speed V1[0], you reject the take-off. V1 is calculated for the aircraft such that above that speed you are able to safely take off and execute a go-around in order to land again on just that single engine. Aborting above V1 is heavily discouraged because usually there's a strong risk of running off the end of the runway. Of course, if you lose…

Yeah in some cases rejecting after V1 is a better choice. If you're going to impact something anyway you'll be doing it with a slower speed and no vertical component in that case.

An airliner in the US did it and the pilot was praised for making that hard decision. Everyone walked I think. I forget which flight.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#576

Post by wkat4242 »

aipatselarom wrote: post #112
klausa wrote: post #109

Earlier quoted context omitted.

It's baseless speculation by someone who doesn't have any relevant expertise, based purely on conjecture not any facts around the accident. It's _exactly_ the kind of comment that deserves to be downvoted here.

The guy's just asking if four engines instead of two would have made a difference? It's curiosity, it's learning, it's looking for an explanation. That's exactly the kind of comment that deserves to be here. >[...] who doesn't have any relevant expertise, Is that a requirement to comment on this thread? Do you fulfill that requirement you brought in?

> The guy's just asking if four engines instead of two would have made a difference?

We won't know until we have all the details and the exact cause of the shutdown.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#577

Post by jgwil2 »

pixl97 wrote: post #338
jgwil2 wrote: post #234

Earlier quoted context omitted.

Call me a "party pooper" if you will but maybe you shouldn't be having "fun" with an accident that will have killed hundreds of people.

On a long enough timeline we all die. Guess we shouldn't ever have "fun".

No, that doesn't at all follow from what I said.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#578

Post by platevoltage »

wkat4242 wrote: post #562
platevoltage wrote: post #458

Earlier quoted context omitted.

I'll never understand why bidets are so niche in the USA especially after there are TP shortages every couple of years. Not to mention how gross cleaning yourself with dry tissue is.

Oh yes I was just writing the same. Water is much cleaner yeah. About half the houses here have a bidet. I think many people in countries like the US or northern Europe wouldn't even know what it's for when they see one :)

I would put it at 1% here. They are extremely rare. Bidet attachments have become relatively popular here over the past decade though. It's been life changing (or maybe butt changing). It's amazing how pretentious Americans can be while having such a gross habit.

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#579

Post by keepamovin »

hanche wrote: post #534
newdee wrote: post #425

Earlier quoted context omitted.

Don’t these Dreamliners also have back batteries?

They have a RAT (ram air turbine) that deploys automatically under specific conditions. It’s basically a turbine providing electric and hydraulic power. It was almost certainly deployed on the accident flight. It will only power the most critical equipment, though. Possibly, that does not include the ADS-B transmitter (which broadcasts position and related data).

This analysis is convincing about being able to hear the sound of the RAT from the crash video: https://www.youtube.com/watch?v=SbDJjgN7Xbo

Re: Air India flight to London crashes in Ahmedabad with more than 240 onboard

#580

Post by bravesoul2 »

impulser_ wrote: post #551
bravesoul2 wrote: post #523

Earlier quoted context omitted.

You are comparing the US pop 350m (?) to rest of the world pop 8850m. Sure planes per capita are higher in US but it's an unfair comparison. Not to say there isn't something there to dive into with data and some countries are safer than others to fly. And definitely some airlines than others.

Yeah, but the US puts significantly more miles on these planes and yet not a single accident has happened. So it's not the plane, unless these foreign airlines are getting the defunct planes. It has to be either poor maintenance or poor pilot training.

Definitely maintenance, pilot training, language, airport feature, topography and climate will factor in.

Id rather look at it in the lens of "is this flight I am booking safe enough" over "US is safer than Non-US"

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