Why don't planes have ejection seats?

When a plane is going down, why don't they have ejection seats for everyone that the captain can just hit a button and send everyone flying with parachutes attached to their seats before the plane hits the ground?

Other answer:

Vincent G:
1- ejection is dangerous. There are pilots who actually die from an ejection
2- planes equipped with ejection seats have a clear canopy above that is jettisoned, or blasted away at the moment of ejection. That canopy is not structural, it does not bear any load. Airliners have a solid roof that is structural, and contains the pressurization of the aircraft. Moreover, jetliners have this overhead luggage bin that an ejection seat would have to go through
3- ejection seats are restricted as to the weight of the person they can safely eject. There is not only a maximum size and weight, but a minimum as well, to the point that pilots who are on the light side have to add ballast to the seat so as to avoid being injured
4- most people walk away from aircraft accident in the first place. In fact, I would venture that the death rate among people who eject is higher than the death rate of passengers in jetliner accident
5- what would happen if someone inadvertently and accidentally press the button? Such a system would NEVER be certifiable. Military airplane are not certified, the pilots who fly them know what they are doing and are trained accordingly.
6- most jetliner accident occur at altitude and speed where most ejection seat would simply no prove effective
7- an ejection seat weight as much as the passenger seating on it. The weight would go up if some shielding is required to protect those who have not yet ejected from the rocket blast of those ejecting, plus the addition of the hatch to let them through, not to mention the reinforcement required to make up for the structural strength lost because of all those holes
8- ejecting over the ocean, at night, in winter would surly save life, right?

The reason we don't do it is because it does not work, and cannot be made to work.

Eric West:
Isis and Al Qaeda would really love that idea. Let's not smuggle a bomb on board, let's just use the ones that are already there!

Ejector seats use explosive and rocket motors, so those sitting down the front of the aircraft would effectively incinerate the guys sitting down the back as they punched out.

This, of course, is the least of your problems, forget cost and weight, think about 400 passengers sitting for 18 hours, as restrained as they need to be to use the seat, which frankly, is too restrained to get up to use the toilet!

There has never been a crash where ejection seats would have made any difference!

Ianab:
Just impractical for all sorts of reasons.

– If you aren't strapped in with a 5 point military harness and wearing a helmet, the ejection will kill you.
– If you bail out at the cruising height and speed, that will kill you.
– If just one seat malfunctions in normal flight it brings the whole plane down.
– The weight and the structural changes to allow this would mean a 747 might carry 100 passengers.
– You are probably safer in a powerless but controlled airline, than you are ejecting. If the plane is out of controil and breaking up, then you aren't going to eject safely anyway.
– I f everyone mailed out of the open ocean they would be scattered over 100 square miles. You would freeze / drown / become shark bait before you could be rescued, even if you got out of the plane alive.
– Most crashes occur with little warning, like missing the runway or hitting a Mt in cloud. No time to eject anyway.

So there is basically no upside to this.

potatochip:
First of all parachutes are extremely heavy. If they fitted each seat with one, the plane will be carrying a lot fewer passengers and cargo. Therefore expect ticket prices to be even more expensive.

Second, not everyone is trained to use a parachute.

Third, airplanes crash differently so there is not always the availability of ejection. Plus imagine if there are over 300 people being ejected at the same time. Parachutes and collisions among passengers will be a high probability. Plus many airplane crashes are survivable.

Matt:
1. There would be so many people parachuting down that there would surely be multiple parachute collisions. This could cause people getting tangled up and unable to get out of their seats when they land, and potential drowning if they are going down over an ocean or seamass.
2. There would have to be a hole in the ceiling with a trap door above every seat, meaning the risk of people getting sucked out of the plane up into thousands of feet in the air would be increased. Also, each trap door would have to seal perfectly, or else cabin air pressure would not be able to be maintained easily.
Brian:
at 30 thousand feet with out a source of oxygen you will dead before you get to a breathable altitude with an automatic parachute. Now lets just say for a second that it was possible and affordable. Could you imagine taking a **** in an airplane restroom and then suddenly while you where shitting being shot out of the airplane.
Angela D:
because there is no need for them.

please provide an example of an incident where ejection seats would have made a difference. i've asked this many times and nobody ever has any answers. why?

The:
Think about how much money that would cost. They have to make planes safe, but cheap as well
Dylan:
Because flying is so safe already that requiring manufacturers to spend money on something like this is just not worth it. Plus there is no way this would even work. Ever.