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What are your thoughts? Ejection from airliner.

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What are your thoughts? Ejection from airliner.

Postby Foxtrot15 » Thu Jan 07, 2016 1:36 am

I found this video talking about a "pod" for airliner passengers to eject in case of an emergency. Bearing in mind that engine failures are not life-threatening emergencies which the video wrongly portrayed, would you use this system as a passenger or pilot?


There are a few problems with this, such as the cockpit crew being unable to escape and the need for a jettisoning explosion, but overall this is still better than individual ejection seats.

What are your thoughts?
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Re: What are your thoughts? Ejection from airliner.

Postby legoboyvdlp » Thu Jan 07, 2016 1:51 am

Perhaps possible; yet to start with, it would need considerable structural changes, so the roof could explode off. Not to mention the risk of the roof hitting the tail.
If the fuselage ejected from the aircraft, with no tail, or wings, it would again need structural change to
1. Add a parachute
2. Make a clean break at the tail, disconnect the wings, and dump extra weight overboard.
3. With a full load of pax, cargo, and the 'center' tank filled, it eould need gigantic parachutes!
4. It would be prohibitively expensive.
5. It could only be used at less than say FL150 wirhout a serious risk of killing everyone, due to the little oxygen found at high altitude. FL410? Forget it! And it would not really be effective at low altitude; just extra weight to carry. Especially since supposedly most incidents happen on takeoff or landing.
6. Ejection systems would considerably increase the weight, which would need extra thrust and thus engines, and thus a heigher weight, and thus less passengers, and thus less revenue. :D
7. You ideally would design a plane that has a way to specifically remove its wings in flight for more effective ejection. This would be a terrorists's dream ... no need to bring their own explosives if they can hack into the control systems (don't even need to disable the parachute deployment, if you can get it to trigger when the plane's low enough, like while it's coming in for a landing ... or on takeoff, so it throws lots of fuel at the same time)


Note: I did not watch the video -- poor internet tonight.
Cheers!
Jonathan
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Re: What are your thoughts? Ejection from airliner.

Postby Richard » Thu Jan 07, 2016 9:07 am

Foxtrot15 wrote in Thu Jan 07, 2016 1:36 am:I found this video talking about a "pod" for airliner passengers to eject in case of an emergency. Bearing in mind that engine failures are not life-threatening emergencies which the video wrongly portrayed, would you use this system as a passenger or pilot?

What are your thoughts?


First thought was that it must be a joke.

1. Getting rid of all that excess weight (the pod) is going to make a single engine climb easy as pie. I'd rather stay on the aeroplane once everyone else has been jettisoned.
2. The thrusters to slow descent are likely to cause significant damage (toasted pax); and in any case where did they come from and how are they fueled.
3. To have the required structural integrity to survive the flight and landing pod would likely be heavy.

The system would only work in a limited number of situations, I can only think of a few incidents where it might have helped, such as the Helios 737 (providing that the pod was pressurised, which in itself isn't an easy system to implement in an airframe).

Ejection seats work because you are fired out of the aircraft at a rapid rate, even when rolled or near the ground they still work. Obviously if you're low and rolled over more than 90 degrees there will be a considerable chance of a probably less favourable ground interaction.
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Re: What are your thoughts? Ejection from airliner.

Postby Michat » Thu Jan 07, 2016 8:57 pm

Every aircraft should have a second chance system. Like it.
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Re: What are your thoughts? Ejection from airliner.

Postby legoboyvdlp » Thu Jan 07, 2016 9:16 pm

I'm afraid it's not going to happen, Michat. The benefits -- what, maybe save three hundred lives in a hundred years?
Not that I value money more than life, but air travel is already very safe. You accept the --very-- slight risk of crashing when you buy the ticket. And of course, unless it is your unlucky day, you arrive safely. There are tens of thousands of planes in the air at the same time. All day. And I only get an average of two dings when my app on my tablet picks up a squawk 7700. So say 50k flights per day according to google:
2 / 50000 = 0.00004. 0.004 % chance to have even a 7700. Not even an emergency landing, much less dying.
And there have been really only a couple of major incidents.
3 in 2015; 6 in 2014. 2 each 2013 and 2012.
So, in 2014, your risk of dying was approximately:
0.0000109589.

The structural changes; fuel penalty; toasted cheese passengers (see Richard's comment) :P ; price; altitude restriction... especially when it would only be useful maybe once in a decade....
not worthwhile.
Nice idea, but...
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Re: What are your thoughts? Ejection from airliner.

Postby HJ1AN » Sun Jan 17, 2016 2:38 am

Any failure catastrophic enough to bring down an airliner would also totally destroy the passenger compartments nowadays, ie bombs, missiles. Otherwise as many mentioned, the plane is built tough and reliable enough and there are enough landing strips around to divert the plane onto if there problems that would not allow the plane to continue flying normally. The only real problem areas are oceans, and even with the ejection, not much fun to survive only to land in the sea.

About safety perceptions - it's funny how in the commercial aviation people are out to convince you that it's VERY SAFE DON'T WORRY, but - in the military sector - and I have some friends who are in the military - they are saying to be alert, it's risky, etc. even for minor things like troop transportation and they prepare for it. I get that there are many differences between commercial and military, loading and unloading of passengers for example, and one needs people to be mentally alert , but the too vast difference in attitude makes me wonder sometimes. Even in oil and gas flights for example, there are plenty of safety briefings. (But of course again, these are normally helicopters)
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