# IT WORKS! New [aircraft] parachute saves four lives

1. May 21, 2004

### Ivan Seeking

Staff Emeritus

http://spaceflightnow.com/news/n0211/22parachute/

The technology to apply this to commercial aircraft already exists though the Apollo program. Aviation will never be the same.

Edit: boy my spelling really sucks when I haven't slept for a day and a night. :yuck:

Last edited: May 21, 2004
2. Jun 8, 2004

### Gokul43201

Staff Emeritus
Right, the airline industry is just waiting to spend millions of dollars on extra safety measures.

Anyway, it was cool to read this as I had previously (a month ago ?) come up with an idea like this (using parachutes) in response to a post by someone who was suggesting firing off a tethered rocket. At the time, I had no idea that it was actually being implemented.

3. Jun 8, 2004

### Staff: Mentor

Its really only for private planes. First, they are small, second they fly lower (and hence can't glide as far) and third, they are much more dangerous than airliners.

I can think of only two incidents in recent memory where this type of system might have made a difference: the last airliner crash (Nov 2001) in the US was an airbus that had its tail rip off causing it to frisbee in. About 10 years ago, an Alaska-air MD-80 or similar plane had a control malfunction in the tail.

There are so few airliner crashes that this may be useful for that it doesn't seem worth it for me.

Last edited: Jun 8, 2004
4. Jun 8, 2004

### aychamo

Err, I'm sure you would have the same opinion if your loved one died on the plane that could have had the parachute, but it just wasn't "worth-it."

5. Jun 8, 2004

### Ivan Seeking

Staff Emeritus
First, not to create any confusion, these are only in use with small aircraft. The system used for re-entry by the Apollo progam can allegedly be modified to work for a commercial aircraft but the economic and engineering problems are obvious. Still, the initial objections [not made here] that such a system couldn't be made are already addressed. It seems that this can be done. I haven't even had time to look at the statistics but here is a link for an air crash database.

http://www.crashdatabase.com/

6. Jun 8, 2004

### Ivan Seeking

Staff Emeritus
What about the planes from 911? This would provide an option of last resort should control of the plane be seriously threatened. This does imply a hefty benefit to cost ratio.

7. Jun 9, 2004

### Staff: Mentor

Well, I dunno - with the money spent on parachutes in a thousand planes, how many more cars could have airbags? Or if you're really into airline safety, how about collision avoidence (ground and in the air) or wind-shear detection. Or we could upgrade our air traffic control computers (the only computers in the country that still need vacuum tubes). Deciding what to spend money on is about weighing risks: the risk of dying in an airliner crash isn't even in the top 100 of the most likely ways you'll die, somewhat below the risk of being killed by lightning. Its not worth worrying about. The only reason people do worry about it but don't worry about dying in a car crash (depending on your age, its in the top 5 of most likely ways you'll die) is because plane crashes, as rare as they are, are more spectacular.

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Looks like I was wrong though - there were 2 accidents with fatalities in 2003 in the US. One was a commuter plane that killed 21 people (was that the one that nosed-up on takeoff and stalled?). The other was a ground crew member who got run over. Thats odds of 1 in roughly 5 million for any particular flight that you would have been involved in a fatal accident, about average for the past decade.
I'm not sure what you mean - could the pilot or co-pilot have punched the chute after having their throats cut? Remote control from the ground (though we didn't know anything until the first plane hit)? A flight-attendant? I can't picture a scenario where a parachute would have made a difference.

It may be reasonable to put them on commuter planes or require them for general aviation - the planes are smaller so it costs less per plane and far more fatalities could be prevented.

Last edited: Jun 9, 2004
8. Jun 9, 2004

### Ivan Seeking

Staff Emeritus
Like I said, as soon as control of the plane is seriously threatened - such as just as the hijacker’s crash through the cabin door.

What strikes me is not how many crashes occur but the money spent for security and safety. Given a failsafe system of some sort, then it seems that the use of aircraft as weapons is made virtually impossible.

Can anyone guess at the cost of such a system? Maybe that number alone would end the discussion. Is possible that this would not be incredibly expensive? For the sake of discussion, what is the cut off price- where this is not worth doing: $10,000,$100,000, \$1,000,000 per plane?

Last edited: Jun 9, 2004
9. Jun 9, 2004

### Staff: Mentor

Well - its one thing for a cessna to float to the ground under a chute, but a whole 'nother for a 757 - there's still a decent chance everyone on the plane will die. Come down in a soft field and you're probably OK. Come down in Queens or a forrest and there'll be problems.

10. Jun 9, 2004

### Ivan Seeking

Staff Emeritus
Though death did not strike me necessarily as a consequence, it would make for some strange and difficult situations, at least.

What do you think of the cost issue? I know this would seem to be a very expensive proposition, but then it strikes me also that this may not be so bad as one might think.

What is the cost of a 7E7 these days? Boeing just sold about 50 to JAL I think…I know they just made a big sale.

Side note: When I was a very young child a Goodyear blimp crashed very near our house. I can still vaguely remember that blimp hanging from the power lines over the Blvd in Paramount…or thereabout. It was quite a sight to behold. Imagine a 777 floating down and landing on your house.

Last edited: Jun 9, 2004
11. Jun 9, 2004

### Staff: Mentor

Dunno about a 7E7, but according to Google, a 777 will run you about a billion and a half. So even if it costs a couple of million dollars, it wouldn't be a large fraction of the price.

12. Jun 19, 2004

### Zorodius

Wouldn't it make more sense to have a button that instantly locks out the pilot's control of the plane and transfers it to the air traffic controllers? Dropping a commercial airliner onto a populated area would be a bad thing even if it was slowed by a parachute, and the hijackers would still have some success, even if they were not able to fly the plane into their target of choice.

13. Jun 19, 2004

### Cap'n Refsmmat

Exactly. The hijackers would just wait until you are over the target city, and then attempt to hijack the plane. The parachute foils their attempt, but the plane still crashes into a populated city, killing many.

14. Jun 19, 2004

### Ivan Seeking

Staff Emeritus
Good point but I don't know if in practice this could be done or not. Someday, sure, but not any time soon I would think. I know that the autopilot usually lands the plane so onboard computer control is definitely possible, but I doubt it would be so easy to hand off control to another location. Also, all that need be done is to damage the controls. I am quite sure that in a pinch, if I were a hijacker, I could take out the autopilot with little panel damage.

Another thought, is it likely that a chute system would fail - resulting in the uninteneded deployments of the chute under otherwise safe conditions - more frequently than it is likely to be of aid. In other words, what is the likelyhood that it would cause more problems than it would solve?

15. Jun 19, 2004

### Cap'n Refsmmat

Only in 0 visibility. Pilots don't really trust the autopilot, all it does in landing is present ILS information, like where the runway is and at what angle, altitude, and that.

16. Jun 29, 2004

Why would that be?

17. Jun 29, 2004

### Staff: Mentor

We kinda already covered this. A 757 floating to the ground under a chute at the same speed that a cessna can touch-down safely will crush itself and anything under it on impact.

18. Jun 29, 2004

### Ivan Seeking

Staff Emeritus
This directly contradicts what I have been told recently by pilots. For example, a few weeks ago I was landing in Dallas. On final approach the plane made an unusual manuever and accelerated strongly for a few moments followed by a return to the glide path. After landing I asked the pilots what had happened. They shrugged and said that the autopilot didn't like something about the approach. This was on an American Super 80.

19. Jun 29, 2004

### Ivan Seeking

Staff Emeritus
Are we sure this is true? I will check the weight to area ratio later, say for a 767, if no one else knows this.

20. Jun 29, 2004

### Staff: Mentor

You guys are talking about two different things. ILS is just presenting information - good information - to the pilot so the pilot can fly the plane. It on its own isn't part of the plane's autopilot. ALS (I think) is the automated landing system that can actually fly the plane to touchdown using the plane's autopilot when linked to some sort of ground-based information system (possibly coupled with ILS). I'm a little thin on facts here too, but I was under the impression that about half the time, the autopilot flies the plane to touchdown.