Could ejector seats save lives in commercial aircraft? [duplicate]

Question

If cost were no issue (it could be done cheaply), would installing ejection seats for passengers possibly save lives?

There are certain scenarios (albeit extremely rare ones), where the crew may know with high probability that everyone on the aircraft is doomed. This might be because both pilots have been incapacitated or died, or the horizontal stabalizer has failed and the aircraft is in a nose-dive, something like that. In this case, the crew could automatically deploy everyone's ejection seats - this could increase the chances of survival.

Of course, one issue is the control of the parachute upon deployment, so I would suggest that some device knocks the passenger unconscious as they are ejected (like a knock to the head - to stop them tampering with anything) and then sensor waits for enough airspace to auto-deploy the chute.

Is this viable?

Edit: This is not a duplicate. The other question asks about parachutes on commercial aircraft but not ejection seats.

Answer 1

Realistically no, the answer is similar logic to this question. If we overlook the weight and size toll there are still lots of practical issues.

• Military jets generally have no (or limited) upper obstructions above the pilot aside from the canopy which is fairly easy to jettison. In a commercial aircraft you have oxygen masks, over head entertainment systems, then the overhead baggage compartment, then all the piping in the upper section of the plane to get rid of. This is assuming you want to use existing vertical exiting ejection seats. Shooting seats out of the side of plane creates a whole new slew of problems (into running engines, into the tail etc).
• You need to be strapped into an ejection seat while wearing a harness so either everyone has to come suited up in a proper harness or you have to provide them. it would take quite a long time to board a full commercial airliner and strap everyone in.
• Everyone would have to wear oxygen masks at all times. You can't go launching people out of a plane without supplemental oxygen. Since an emergency can occur at any time to be a viable solution everyone would have to sit there huffing on O2.
• Ejection from an aircraft is very physically demanding on the body and even fighter pilots in top physical shape still can suffer severe injuries and may never fly again. You would be hard pressed to subject many average people to this successfully.
• You now have hundreds of parachutes to check and re-pack all the time to make sure the seats are in good order.
• On most commercial aircraft there is often bags stored on the floor, stuff in peoples laps etc. If seats start shooting out of the airframe all that debris is going with it and is quite liable to injure someone
• And finally, who gets to pull the handle, who gets to decide everyone on the plane is about to go for quite the ride?

Answer 2

No, it's not viable:

• Using ejection seats requires a certain level of physical fitness, you need strong bones, children and older people would get seriously injured or die using seats. Healthy people in the prime of their life still get injured or killed using seats
• Using ejection seats requires recurrent training in getting the right posture before the seat is used, if someone using a seat is not in the right position the g forces will give them serious injuries. Just getting people strapped in requires skills, usually this is done with assistance from ground crew. If the occupant is not in the right position they will lose limbs from contact with the airplane as they are ejected from it. They also need training on how to land with a chute and what to do if they land in water, etc. Keep in mind the word recurrent here, so that's training for millions of people, over and over. Try teaching a 3 year old how to sit in an ejection seat, getting them to sit period is nearly impossible!
• Most of the time passengers would not be in position to be ejected, they're walking around, they've got bags out, using laptops/tablets, eating with tray tables down, in order to be successfully ejected bags would have to be cleared (no place to put them though, there's no overhead bins as the seats have to go up), food trays cleared, people seated and strapped securely. It would take minutes to do this
• Most aviation accidents are sudden, with not enough warning to make ejection seats useful. There are very few where there's enough warning that an escape system would help. Also, you'd have to have several seconds for that many people to eject, you couldn't punch them all out simultaneously as they'd get tangled up
• Ejection wouldn't necessarily put people into a more survivable position. If you eject 300 people into the middle of the North Atlantic they will be dead in minutes from exposure

So in order to do any good you'd have to have enough warning and the airplane would have to be in the fortunate position to be in search and rescue range of a facility that can save an airplane full of people before they drown or die of the injuries sustained in the process. That's a tough sell.

Note: I'm assuming that the seat design itself would compensate for the lack of protective clothing, helmets, etc, and would also supply oxygen for high altitude ejections. If not, passengers would need to be wearing flight suits, helmets, etc.

Answer 3

Ejector seats are effectively explosives.
(what, you thought they were launched by rubberbands?)

You want to put explosives in every row of the cabin?

The same cabin where cell phone batteries sometimes catch fire, passengers spill drinks and throw up, and all equipment is kicked, pushed, knocked, and abused?

And you want those ejector seats to be completely safe so they never go off by accident or during a fire, but are also completely reliable so they always go off when needed.

Ejector seats throughout the cabin would turn even a "routine" galley-fire into a mass casualty mid-air explosion.

Answer 4

TL;DR: Nope!

This page goes into great detail about why ejection seats for airliners are a very ungood idea, so we'll just sit back and let them do the talking:

Pro: Safe recovery of passengers in the event of a catastrophic disaster.

Con:

1. Danger to maintainance crews

2. Danger to passengers due to accidental discharge

3. Possible injuries to passengers due to use

4. Weight increase

5. Larger seat area requires fewer seats in given area

6. Egress hatch requirement requires considerable redesign of cabin fuselage

7. Cost- Ejectable seat would add costs for:

   a. Redesign costs

   b. Development costs

   c. Seats (military seats can cost upward of $100,000 per unit)

   d. Periodic maintainance

   e. Replacement parts

   f. Maintainance crew training/explosive certification

8. Minimal time of use

[...]

...Parachutes require more than just a simple lap belt. At a minimum, the harness requirements include a pair of leg straps, a pair of shoulder straps and a chest strap. These straps must be adjusted for each individual to be a snug (read uncomfortable) fit for each passenger... In the case of a situation requiring a mass ejection, this would have to be delayed until ALL passengers AND crew are strapped in securely prior to depressurizing the cabin, blowing the hatches and initiating ejection.

When the cabin is depressurized and the hatches are jettisoned, the passengers would be exposed to the lower oxygen pressure in the upper atmostphere, the wind blast which would cause flail injuries and injuries by loose flying objects such as handbags, cameras, camcorders, trays, carry-on bags, and other objects.

Jettisoning a large number of hatches in the roof of an airliner will also cause significant changes in the aerodynamics of the aircraft leading to control problems for the flight crew.

The aircraft structure would require massive modification to make ejection seats feasable, including strengthing the cabin floor for the additional weight and the recoil of the seat firings. The cabin roof would have to be configured with the aforementioned hatches. The fuselage would therefore need a major increase in supports to allow it to hold its shape when the hatches were jettisoned. Overhead baggage compartments, and underseat storage would have to be eliminated to give adequite clearance above and, because of the seat depth, below. Legroom would have to be adjusted to make sure that adequite clearance was maintained on ejection to prevent leg injuries.

Mechanical ejection (spring/bungie) would provide inadequite thrust to ensure that passengers would clear the empennage. Compressed gas systems that would have enough force would provide too great of an initial force for safety. This means that pyrotechnic rocket/catapult systems be used. These systems would necessitate significantly increased training for maintainance personel, cabin and flight crews. The pyrotechnics would require maintainance on a regular basis in an explosive rated hanger with explosive rated storage.

The ejection sequence would have to be from the rear to the front of the cabin, with the flight crew being the last of all to be ejected. In an airliner with 30 rows of seats, the seats would have to be jettisoned in row sets, with seperation rockets to insure dispersal of the seats and prevent mid-air seat collisions. There would have to be a delay between rows for the same reason. This delay in military jets is in the vicinity of .4 to .5 second. This adds up to some 15-16 seconds for a full ejection of the aircraft. Seats that are unoccupied must be weighted to ensure that they seperate in a predictable path. While the seats are firing, the aircraft would be exposed to forces from the catapult charges, and the center of gravity would be changing rapidly. This would cause significant difficulty to the flight control system to maintain stability.

[...]

Conclusion:

Passenger survival by seperating the passengers from the aircraft prior to impact is not an option that could be easily or cost effectivly implemented.