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Seat Belts

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Seat Belts


Why wear them?

FAR 91.107 requires the use of seat belts for all occupants. More importantly, in the event the aircraft crashes before a safe jump altitude is reached. A seat belt may make difference between surviving the landing and not surviving the landing. If you are seated towards the tail, not wearing a seat belt and the aircraft crashes, you will become a projectile, hurtling towards the front of the aircraft. The force of the collision as you reach the jumpers near the front of the aircraft could kill you and the jumper(s) you collide with. Any loose item in the aircraft will also become projectiles. A camera helmet moving at 80 knots slamming into a jumper sitting near the pilot can easily kill a jumper that would have otherwise survived the landing, possibly without injury. Camera helmets, helmets, sky-surfing boards, tubes, any loose article must all be secured before take off. Do not allow the pilot to take off if all the jumpers are not wearing their own seat belt and all loose article are not secured.

How to wear them.

Sitting on the floor, facing the tail with a seat belt over your lap, will not restrain you in the event of a crash. You can easily slide out from under the belt. The seat belt must be passed through the jumper's harness if sitting on the floor to restrain the jumper properly. Putting the "tab" end of the belt through the harness will make it easier to remove the seat belt than putting the "buckle" end through the harness. If the aircraft does crash, having the set belt attached to your harness will likely result in less injury than a single strap across your lap. The harness will spread the forces better.

When to take them off?

Different drop zones have different minimum altitudes for removing seat belts. Jumpers tend to want to remove them as soon as possible in order to get more comfortable. Before taking off your seat belt, look outside the aircraft at the ground and ask yourself, "Am I willing to exit the aircraft from this altitude?" If the answer is "no", then in the event of an aircraft emergency, you would have to re-connect your seat belt and should not have removed it in the first place. If the answer is "yes", there are several more factors you must take into consideration. If the aircraft's engine(s) [one for single engine aircraft, both engines for twin engine aircraft. Twin engine aircraft may still be able to climb or maintain altitude on one engine, dramatically increasing the pilot's and jumpers' options in the event of an engine failure], quit, the aircraft will immediately begin to descend. Most jump ships climb at an airspeed close to the best glide speed of the aircraft, meaning that if the engine(s) quit, the pilot doesn't have any excess airspeed to use up before establishing a descent. In other words, the pilot must begin to descend immediately after losing the engine(s) in order to avoid stalling the aircraft. If you are seated next to the door, you may be able to exit quickly, at or above the altitude you looked outside at and determined you could leave the aircraft in the vent of an emergency. If you are seated near the pilot of a larger jump ship, by the time you reach the door, you will be well below the altitude you determined you could safely exit the aircraft at. What would you do now? You are in an aircraft without an engine(s), too low to exit, without a seat belt on, standing next to an open door. Not a good situation to be in. Before removing your seat belt, consider how much altitude will be lost before you can reach the door and exit. Remember it will take time for the jumper(s) near the door to recognize the emergency, decide what action to take (exit or stay, this should be based on the DZ's policy for emergency exits), then open the door and exit. During this time, the aircraft will be descending. The lower the pilot gets, the more distracting and dangerous it will be for jumpers to be moving towards the door, changing the weight and center of gravity of the aircraft, increasing the pilot's already very high workload.

For example, if you are sitting next to the bulkhead of a twin otter (i.e. last out of the aircraft) and you take your seat belt off at 1,000 feet and the engines quit at 1,100 feet. By the time you reach the door, you will be too low to exit. There will likely be some people between you and the door that feel it is too low to exit, blocking, or at least making it difficult for you to get to the door, slowing you down, and resulting in even less altitude when/if you do reach the door.

Never re-connect the seat belt together after taking it off. The loop of a connected seat belt creates a snag point for jumpers exiting after you. Even if you do not wish to wear a seat belt, wear one to protect the pilot from legal action (seat belts are required to be worn by the FAA) and to protect your fellow jumpers.

Getting to the door in the event of an aircraft emergency of any jump ship will probably take more time than you think it will. Keep your seat belt on until a safe emergency exit is assured.

Hook

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>If the aircraft does crash, having the set belt attached to your
> harness will likely result in less injury than a single strap across your
> lap.

I'd have to disagree here. Harnesses are designed to take loads exactly one way, and that's through the top of the main lift webbing. If you're sitting facing the tail, and you loop it through the side of your lift webbing, you will be rotated 90 degrees by the force of the crash, and that amount of rapid rotation is bad for you and the people around you. If you're sitting on the floor and you want this sort of protection, passing it through both lift webs or chest straps would be the ticket - although you still can't guarantee much.

Seat belts in jumpships are simply not tested to perform at all in any serious crash. In a typical side-bench otter, the bench will collapse if there's a significant impact, and that could easily cause the seatbelt to break all your ribs and/or your back. Also, when you're sitting sideways, any forward deceleration will try to tilt your head sideways, and that's the most likely direction your neck will break in.

That being said, there is still some evidence that seatbelts increase survivability in serious crashes, since some crashes (the perris 91 crash) show evidence of people moving long distances inside the plane and becoming projectiles. This isn't good for either the projectile or the person the projectile hits.

In any case, there are still plenty of other good reasons (preventing load shift in case of sudden manuever, safety in minor accidents, not getting the pilot busted) for wearing seatbelts.

>and you take your seat belt off at 1,000 feet and the engines quit at
>1,100 feet. By the time you reach the door, you will be too low to exit.

I suppose that depends on your minimum personal exit altitude.

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Why wear them?

FAR 91.107 requires the use of seat belts for all occupants.



For taxi, takeoff and landing.

Quote


If you are seated towards the tail, not wearing a seat belt and the aircraft crashes, you will become a projectile, hurtling towards the front of the aircraft. The force of the collision as you reach the jumpers near the front of the aircraft could kill you and the jumper(s) you collide with.



Not could -- WILL.

All you have to do to understand this is read or hear accounts of a very famous skydiving accident in which people were not wearing seat belts and this becomes horrifyingly clear.

If anyone thinks it's not really a big deal, have them talk with Dan B.C..
quade -
The World's Most Boring Skydiver

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>If the aircraft does crash, having the set belt attached to your
> harness will likely result in less injury than a single strap across your
> lap.

I'd have to disagree here. Harnesses are designed to take loads exactly one way, and that's through the top of the main lift webbing. If you're sitting facing the tail, and you loop it through the side of your lift webbing, you will be rotated 90 degrees by the force of the crash, and that amount of rapid rotation is bad for you and the people around you. If you're sitting on the floor and you want this sort of protection, passing it through both lift webs or chest straps would be the ticket - although you still can't guarantee much.



True. In a C-206, I attach the seat belt to my chest strap. It would hold me better than laying it across my lap, where I don't think it would very much. Also, attaching it to your harness prevents you from slipping out from under it and becoming a projectile.

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>and you take your seat belt off at 1,000 feet and the engines quit at
>1,100 feet. By the time you reach the door, you will be too low to exit.

I suppose that depends on your minimum personal exit altitude.



LOL- very true.

Hook

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I've yet to see seatbelts that you could easily get through both lift webs. Most of the time they are mounted to one side and way too short. Take the average Otter when sitting on the floor or bench, facing the tail. You can barely snake the belt through the harness.
If facing into the middle of the aircraft I've seen, I think you have a better chance of getting the belt in as how I tihnk you are describing it.
Something is better than nothing I suppose, but the seatbelt configurations in most jumpships don't exactly fill my with a warm fuzzy feeling.
JJ
JJ

"Call me Darth Balls"

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>In a C-206, I attach the seat belt to my chest strap.

I think in a crash, facing backwards, a chest strap is better than a main lift web from a kinematics point of view, but I would worry that the chest strap hardware would fail under any significant load. That's pretty weak stuff. I'd be suprised if it even took a 1000 lb load successfully, and that's only a 5G crash.

A while back I was talking with Mick Cottle about coming up with a standardized restraint system. The ideal would be something like a belly band connected to the harness with an anchor point in front. Alternatively a retrofit could pass through the hip rings of articulated harnesses. In the plane you'd just have short pieces of webbing with biners on the end to attach to the harnesses. A load limiter would decrease impact forces. It would take a lot of work by the FAA, USPA and equipment manufacturers to certify such a system though.

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Why wear them?

FAR 91.107 requires the use of seat belts for all occupants.



For taxi, takeoff and landing.

Quote


If you are seated towards the tail, not wearing a seat belt and the aircraft crashes, you will become a projectile, hurtling towards the front of the aircraft. The force of the collision as you reach the jumpers near the front of the aircraft could kill you and the jumper(s) you collide with.



Not could -- WILL.

All you have to do to understand this is read or hear accounts of a very famous skydiving accident in which people were not wearing seat belts and this becomes horrifyingly clear.

If anyone thinks it's not really a big deal, have them talk with Dan B.C..




I believe there were two, about 10 years ago, where no restraints were used and multiple fatalities might have been avoided. Conversely, I saw a Skyvan go off the runway and into a ditch about 3 years ago. All on board were belted in, and it was a non-event as far as injuries were concerned.
...

The only sure way to survive a canopy collision is not to have one.

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Not to get this thread of subject, but let's add something about either wearing your helmet, or strapping it in with the seat belt.
Nothing gets to me faster than a plane load of jumpers with one or two of them just holding their helmets in their hands on take off. I don't care if it's hot, but the helmet on. (Yea, it's me the bossy one at WFFC that tells everyone to put their helmet on for take off)
Thanks :)
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. - Edward Abbey

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Not to get this thread of subject, but let's add something about either wearing your helmet, or strapping it in with the seat belt.



Quote

Camera helmets, helmets, sky-surfing boards, tubes, any loose article must all be secured before take off. Do not allow the pilot to take off if all the jumpers are not wearing their own seat belt and all loose article are not secured.



Secured = worn or belted in.

Hook

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Secured = worn or belted in.



Sorry, I was on the way out the door and read your first post quickly. I guess I learned not to do that now:$

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Do not allow the pilot to take off if all the jumpers are not wearing their own seat belt and all loose article are not secured.



I would so love to do that, but in a real world what do you think everyone on the plane would do?
It's bad enough the looks I get when I ask jumpers to secure their helmets.
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. - Edward Abbey

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No sweat:D

Who cares what everyone on the plane would do? If the plane crashes and they slam into you, killing you would you care what they thought then? I think wear ing a seat belt is a sign of respect for your fellow jumper's safety. Like Bill V. pointed out, they aren't designed to protect the jumper wearing them very much, but at least you won't kill someone else.

Hook

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Does anyone wear seatbelts in a c182?

Hypothetically you could have a plane with some padding on the floor and the seatbelts are under it. Does anyone know a way around this?

Gale
I'm drowning...so come inside
Welcome to my...dirty mind

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Good, then we're on the same page. The next time we're at a certain Colorado DZ together and the video guy starts giving me a hard time cause I've asked him once again to put or strap in his helmet, you can back me;) I even talked to the DZO of the DZ and they didn't seem too concerned about the video guy doing what he was doing :S The video guy just said "But I always do it, and if you don't like it, then don't get on the plane with me". >:( You know me, I now check the loads that are manifested before I manifest myself.
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. - Edward Abbey

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Does anyone wear seatbelts in a c182?

Hypothetically you could have a plane with some padding on the floor and the seatbelts are under it. Does anyone know a way around this?

Gale


In the 182 that I usually jump from, the belts are all attached at the edge of the padding. On jump run, the belts are shoved under the padding to prevent snags.

If that isn't possible in your plane, cut holes in the padding.

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Does anyone wear seatbelts in a c182?

Hypothetically you could have a plane with some padding on the floor and the seatbelts are under it. Does anyone know a way around this?

Gale



Yes, and yes.
...

The only sure way to survive a canopy collision is not to have one.

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The only time I wore a seatbelt on a jump plane was the 'informative' flight before my first jump. We always make the passengers who occasionally fly with us wear seat belts (usually with comments like "if you're not wearing it, you'll have to exit with us when we get to altitude"), but I don't think I've seen a skydiver use it more than five times.
I am not saying I'm completely against seat belts, I'd just like to point out some things that may be incogruent with what everyone else was saying; unless the plane takes off and immediately falls down again, you have time to prepare for a crash landing, and the procedure I have been taught for this situation is to get as close to each other as possible, with every diver holding the person behind him/her tightly to him or herself. This way everyone functions as one big object as opposed to everyone being a small object capable of flying into others. To do this, seat belts have to be unfastened, otherwise there are gaps between people. Any comments on this procedure are more than welcome.
And another situation where seat belts might or might not be useful is if a plane makes a sudden change in either speed or direction; if it's a small change, a seat belt doesn't make much of a difference and if it's a big one, it could mean everyone will have to get out in the very near future- and in this case fastened seat belts would just mean more time wasted and more panic.
Well, as I was saying; I'm not against seat belts and will probably reconsider using them at least on take-offs on loads that are not completely filled (in such cases as was our record-breaking 12 skydivers + 2 pilots in a Pilatus Porter, everyone is already so close to each other that the mechanics of a single large body apply)
So what do you think of all this?

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I am not saying I'm completely against seat belts, I'd just like to point out some things that may be incogruent with what everyone else was saying; unless the plane takes off and immediately falls down again, you have time to prepare for a crash landing, and the procedure I have been taught for this situation is to get as close to each other as possible, with every diver holding the person behind him/her tightly to him or herself. This way everyone functions as one big object as opposed to everyone being a small object capable of flying into others. To do this, seat belts have to be unfastened, otherwise there are gaps between people. Any comments on this procedure are more than welcome.



You have to be kidding me.

Hook

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Bill, I don't thing jerry81 would like me on his aircraft.

Jerry81, is this for real? Where do you skydive at that allows this to happen?
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. - Edward Abbey

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>and the procedure I have been taught for this situation is to get as
> close to each other as possible, with every diver holding the person
> behind him/her tightly to him or herself. This way everyone
> functions as one big object as opposed to everyone being a small
> object capable of flying into others.

This works about as well as a mother who puts her hand in front of an unrestrained child riding in the front seat to protect them from a crash.

Some numbers for you:

Let's say your pilot stalls a twin otter trying to deal with an engine problem close to the ground. He manages to keep the wings level but cannot recover in time. Fortunately he plows into relatively soft desert sand. Vertical speed is about 60kts at impact, horizontal speed is 30kts.

This is a pretty "good" crash. Speeds are low, and the soft desert allows some attenuation of impact. The landing gear shears off, and the plane digs an 100 foot long furrow as it slides to a stop. Maximum horizontal deceleration is 10G's, averaging 4-5G's over the course of the deceleration. Again, those are very survivable numbers in a car or commercial aircraft.

Let's assume you are unbelted, and you're near the bulkhead. Further assume most people weigh around 200 lbs with rig. Your body will feel a force of 20,000 lbs (the weight of, say, five cars) as everyone else slides towards you. The guy on the end might try grabbing the door frame, but just to keep himself from sliding into you he'd have to be able to lift 2000 lbs (his body weight at 10G's.)

And that's just in the horizontal direction. In the vertical, you might get a foot of deceleration when the bench collapses, another foot of crumple in the body of the aircraft and soil compaction. That's 20G's, so you will also be slammed against the floor with a force of 4000 lbs before that 20,000 lbs gets applied to you.

Then there are the projectiles. Let's say a jumper was sitting on the back bench and couldn't hang on. He comes flying forward and hits you at a speed of around 70mph.

All in all, that's not such a good experience. Had you been belted in separately, each jumper would have loaded their seatbelts with around 2000 lbs, and if the belts held, you wouldn't have to deal with their weights.

>And another situation where seat belts might or might not be useful
>is if a plane makes a sudden change in either speed or direction; if
> it's a small change, a seat belt doesn't make much of a difference
> and if it's a big one, it could mean everyone will have to get out in
> the very near future- and in this case fastened seat belts would just
> mean more time wasted and more panic.

However, fastened seat belts also means that everyone doesn't end up in the tail or on the ceiling. Such a weight shift may not be recoverable by the pilot.

>(in such cases as was our record-breaking 12 skydivers + 2 pilots in
> a Pilatus Porter, everyone is already so close to each other that the
> mechanics of a single large body apply)

If you someday talk to someone who pulled survivors out of the Perris otter, it will become clear that that theory doesn't work. I once had to get people out of a crashed cessna, and three people were occupying a space that had previously been just the pilot. The two students in the back were belted in and were OK; they didn't move much. It made a believer of me.

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It is accepted in the United States that seat belts should be worn.

The question of if a jumper should wear his seatbelt is settled - the law says that he must, and the pilot could have his licenced suspended if a jumper does.

The question of whether the law is correct, is also mostly settled. Few people ever complain of wearing one, and there is little debate if the rules are appropriate. I supose like seat belts in cars, there will always be people who think they have better chances without, but most people believe that history has proven otherwise.

_Am
__

You put the fun in "funnel" - craichead.

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You know, I really hope Jerry is joking or trolling and isn't that reckless.

Everytime I get in the plane, the seatbelt goes on, hell, that's more consistant then when I'm driving my own truck. I'd rather deal with the extra minute it takes to be safe (and legal) then die a stupid death in a plane crash.


(on a side note, the joke at my DZ is in the case of an emergancy and impending crash, everyone gets on their heads. That way when the NTSB tries to investigate, it'll confuse the hell out of them. Thats only a joke, though).
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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First of all, I am not kidding. This is the actual emergency procedure I had to memorize before jumping.
I also think that physics-wise, it kind of makes sense and Bill already pointed out that a single point of attachment could do more damage than good in the case of a sudden stop (crash). [edit]Thanks for the values on crash forces- it does make sense to wear a seat belt if you look at it this way, even though 2000 pounds applied on the small surface a seat belt covers sounds quite unpleasant, too. [/edit]
And Flyangel- even though you might get some annoyed looks from me and my fellow jumpers, I'd never not want to be in a plane with someone just because they are (over)concerned with safety. The only people I really don't like on my load are the, uh, well, constant and unapologetic stinky windbreakers :S. (I know this guy who would be, if it were put to vote, kicked out on most every load as soon as the altitude was safe).
Oh, and I mostly jump all over our small, 13-year-old republic of Slovenia. Commercial skydiving is a relatively new thing here- old rules haven't been revised yet and even so they are not enforced very strictly. [edit]Yes, everyone has to more or less play by their own rules of safety- a seatbelt, as I have said, has just become one of mine. [/edit]
Jerry

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