Why no Parachute System for Civilian Aircrafts?

Over the past few weeks, 4 civilian aircraft were destroyed causing massive casualties.
this week alone, there were 2. One in Taiwan another over Africa


I'm thinking why has no one suggested or designed a dual deploy parachute system for aircraft?
I'm considering the tail end, right below the tip of it, provide a little bay for a drogue and a main parachute that could slow and land a 600MPH aircraft.
Is that too hard to design??

Google Cirrus SR22


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donperry said:

Over the past few weeks, 4 civilian aircraft were destroyed causing massive casualties.
this week alone, there were 2. One in Taiwan another over Africa


I'm thinking why has no one suggested or designed a dual deploy parachute system for aircraft?
I'm considering the tail end, right below the tip of it, provide a little bay for a drogue and a main parachute that could slow and land a 600MPH aircraft.
Is that too hard to design??

Click to expand...

Simple answer-- $$$

I've seen designs in aviation magazines years ago for a prototype system that would jettison the entire passenger cabin between the cockpit and tail... just pop the whole thing out like a giant beer can via rockets, then deploy parachutes from each end to lower it to the ground.

It would of course require a purpose-built aircraft design, since it would be a near total redesign of current aircraft flying... so unless everybody retired their existing aircraft and replaced them with these new ones, most folks would still be on the old type non-jettisonable cabin type... and it would take literally decades to phase in new aircraft and replace all the old ones in actuality. The other thing is, such systems would weigh A LOT... and greatly complicate aircraft design and construction, and would require periodic inspection, service, maintenance, etc, further complicating the aircraft's maintenance and increasing costs all around, in design, maintenance, testing, operations, etc. It would also be mostly dead weight for the useful life of most aircraft, since it would only be used in a few extreme cases... dead weight is lost cargo capacity and requires fuel to propel, raising fuel costs and reducing the payload capacity of the aircraft throughout its useful life, if only to save perhaps a half dozen aircraft over the lifetime of an aircraft type's lifetime, out of hundreds or perhaps thousands actually constructed and operated to retirement.

In short, poor return on investment, and too much added cost for the benefits... Statistically speaking, air travel is still safer than other forms of transportation... Course if it happens that a bunch of planes crash in close proximity timewise to each other, or you happen to be on one that crashes, statistics don't do much for you... but numerically, when one figures how many flights occur every day all over the Earth, it's really a miracle more don't crash than they do...

It's sorta like the Space Shuttle... a lot of early proposals for the Space Shuttle had escape systems for the crew, jettisonable cabins that would deploy parachutes to land in the sea, things like that.... but it was ultimately found that the shuttle could either 1) have an escape capsule/crew cabin or 2) carry a payload, not both... the mass of the system to design it for the crew cabin to act as an escape capsule and have jettison rockets and parachutes and such necessary for a safe landing was SO much that it left little or nothing for the payload capability...

Later! OL JR

Cirrus is already doing it and has been for years. Also BRS, Ballistic Recovery Systems, has been designing parachutes for ultralights and hang gliders for many many years.




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BRS systems only work for slow, light weight aircraft. And even then, the idea is that the aircraft itself is part of the crash structure in Cirrus designs.

Modern airliners are essentially hollow tubes designed to be braced from expanding, but have somewhat poor fore/aft bracing. Most structure beefing are in the lifting surfaces...which makes sense...they have to hold most of the weight. Look at most modern airliner ground accidents...the fuselage usually cracks long before a wing. A tail mounted chute would simply rip off the tail on a current airliner.

Encapsulated ejection systems (basically a small verison of what you are proposing) have also been around for years...one of the largest was the in the B-1A, which ejected the entire crew compartment (basically the size of a small apartment) and was supposed to lower the whole thing down safely. Unfortunately, it was too complex (and partially failed the one time it was actually used) and was changed to the 4 individual ACES II system.

You'll note MH17, the 777, was downed by what was probably a large, radar guided SAM. Those missiles are designed to target the center of the radar paint, which would be the wing box that holds the main structure and the fuel. It was probably shredded by the missile's large warhead, which pretty much would have destroyed the fuselage integrity...no chute system will help you at that point.

Finally, statistically most modern airliner accidents happen during the takeoff/local operations/landing phase...areas where a ballistic parachute simply wouldn't do you much good even if it were practical...things like Air France 447 or MH17 are rare compared to something like the Asiana flight.

Airliner accidents are tragic, but they are news worthy because they are rare. All you need to do is look at the number of people who have died in airliner accidents for a given year verses number who have died in traffic accidents for that same year.

I'm far more concerned about the trip to and from the airport than the airplane ride itself.

FC

Calculate the size and the weight of the parachute required to make a difference and you will see why it won't work.

The G-11 cargo parachute is the largest cargo parachute and has a 100' diameter and can suspend 5,000 pound and weighs 250 pounds. https://www.millsmanufacturing.com/.../14-products/44-g-11-cargo-parachute-assembly Up to 8 can be ganged together to drop 40,000 pounds and would weigh about 2,000 pounds plus the weight of the deployment system.

A Boeing 777-300ER airliner typically carries 386 passengers and has a maximum landing weigh of ~550,000 pounds. It would require 110 G-11 cargo chutes weighing more than 28,000 with rigging but not counting the deployment system! The weight and volume alone would reduce the capacity of the aircraft by ~150 passengers! The diameter of the extended canopy alone would exceed 1/4 mile. Not only is it not practical, it assumes an intact aircraft, and if the aircraft is intact, you can glide it so you don't need chutes!

Aircraft that are shot down are probably on fire and most likely not intact. Ballistic parachutes don't work under those conditions. Aircraft that crash in bad weather encountered at altitude experience extreme turbulence or icing. The parachutes would be destroyed and/or fail under those conditions. There just aren't many cases where parachutes would be useful to a large commercial aircraft in trouble as intact jetliners are easily controllable and glide well if they are intact.

Bob

Cirrus are far from slow.

The OPs question was about civilian aircraft, not just commercial airliners.

BRS systems are independent of using a part of the aircraft, in fact ultralights landed with a BRS system can be immediately flown again assuming the aircraft did not experience a structural failure requiring the system be used.

Cirrus aircraft on the other hand are destroyed if the parachute is fired.



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FC got it right. The Cirrus is slow compare to commercial turboprop and turbofan aircraft. The SR22 max cruise speed is 183 KTAS versus 300-400 KTAS for turboprops and 400-600 KTAS for turbofans. The deployment forces should increase as V^3 so it is a big deal, and would shred a Cirrus class BRS system.

A/C that get shot down do not remain intact for long and usually catch fire. This is the reason why military warcraft have ejection seats/capsules. When the whole aircraft contains passengers you have to recover the entire aircraft intact, and that just isn't possible under shoot down scenarios. The same applies for out of control situations. In military warcraft, the pilots punch out or the crews bail out. That's not possible in a military transport or with a jetliner containing hundreds of passengers.

Bob

weight etc, comes in it it, so does $$$, but any decent enough parachute system would be of no use if the explosion, etc is enough to blow the fuselage in half because the parachute system would probably either be blown away, or suffer too much damage.

The systems for light aircraft are mostly there in case the engine goes out, a wing falls off or you run out of gas at 15,000ft, quite a few of them aren't really set up for the best glide recovery.

I don't think this is feasible or practical. I used to wonder why we didn't build cars like my matchbox cars that can not be damaged, then we could get in and pack ourselves inside with Styrofoam and drive around worry free. Sounds simple, right?

Just for the record, I have jumped out of a 727 at 15,000', and my parachute worked fine!

Granted he had slowed to about 160knts when I bailed out, still felt like getting shot from a cannon, I waited until I had slowed down even more in freefall to deploy my chute.


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IF a parachute system could be made light enough and strong enough to make it cost effective, and
IF the passenger cabin could eject and the parachute could safely return it to the ground, and
IF there was a system that could detect an incoming missile and eject the passengers before the missile struck...

... the terrorists would only need a second missile to target the now much slower moving passenger cabin on it's way down.

Lowpuller said:

Just for the record, I have jumped out of a 727 at 15,000', and my parachute worked fine!

Granted he had slowed to about 160knts when I bailed out, still felt like getting shot from a cannon, I waited until I had slowed down even more in freefall to deploy my chute.


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Click to expand...

D. B. Cooper!!
I always though you survived.

M

Lowpuller said:

Cirrus are far from slow.

Click to expand...

Cirrus are very slow, depending on your frame of reference.:wink: And BRS is a marketing ploy. A placebo drug to comfort pilots with substandard airmanship.

If a plane is hit by a missile it is unlikely the passenger cabin would be intact to be saved by a chute. In other instances, yes, but the cost to passengers would be huge for all the extra weight of the recovery system. Airlines will reduce the static weight of a plane by 50 to 75 pounds to save on fuel if they can.

watheyak said:

And BRS is a marketing ploy. A placebo drug to comfort pilots with substandard airmanship

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I would not be so critical.

Last month small airplane (SR22) lost its engine and did not make it to Hanscom runway. Pilot deployed BRS and landed into the trees. No injuries, pilot and passenger literally walked away from plane crash. (local hospital checked them out and released an hour later).

It was a block from business district where I work during lunch time (what an entertainment!!). I'm not an expert but it did seem like the parachute slowed down the descent and helped save the crew.

-Alex

watheyak said:

And BRS is a marketing ploy. A placebo drug to comfort pilots with substandard airmanship.

Click to expand...

Sure...and ejection seats are for men without manly beards.

Give me a break.

FC

FastCargo said:

Sure...and ejection seats are for men without manly beards.

Give me a break.

FC

Click to expand...

Or people over 6ft... that was my problem.

See
https://cirrusaircraft.com/static/img/CAPS_Guide.pdf

The cirrus parachute is mostly for "out of control" type accidents or damaged plane accidents. The problem is that a lot of the "out of control" accident airplanes would be going too fast (~140 KTS)for the parachute to work. So while it is better than no parachute (As far as safety is concerned), it is still a long way from being a fix all.

One of the earliest Cirrus BRS deployments was right here in DFW near Addison airport. It had zero to do with poor airmanship and everything to do with a really bad maintenance error involving the aileron hinges on one wing.

The aileron came partly loose and was causing serious handling problems. The pilot fired the chute and walked away from the landing.

BRS is fine on smaller aircraft, but is a non starter on large aircraft. No trained engineer would ever suggest it as a possibility due to the many impossible details, described in previous posts.