Four point restraint

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drotto

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drotto
I was reading the thread about the crash of the Malibu at Oshkosh, and how one of the first impressions from the crash was that three point seatbelts break ribs. Got me to thinking how many planes have STC systems to go from three to four points. I am talking common planes: 172, 182, PA28, PA32, etc. More specifically, I am usually in a PA32 (see another thread), is there a four point system available?
 
Four point belts allow submarining and severe spinal injuries. There is an STC for my plane available, but my research convinced me that the factory belts are a better choice. Now if a 5 point were available, it would be a no brainer. But it isn't...
 
rwellner98 said:
Four point belts allow submarining and severe spinal injuries. There is an STC for my plane available, but my research convinced me that the factory belts are a better choice. Now if a 5 point were available, it would be a no brainer. But it isn't...
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Im not sure that can be applied to "all 4 point harnesses"

I had the impression that spinal cord compression injuries due to 4 point harness systems were due to the harness attachment point being lower that the shoulders, like the hooker add on ones that attach to the rear seat lap belts.

So in frontal impact the shoulders are pulled down when the anchor is below the shoulders. So if the 4 point harness is anchored above the shoulders this downward force does not exist. :dunno:
 
Pretty sure "Murphey" has a 4-point setup in a PA-28. Maybe she will respond here. Seems like the shoulder straps are mounted from the ceiling, not the seat itself.
 
The main risk with my four point harness is not fitting it low on the hips. The two shoulder belts pull up on the two lap belts that they tend to creep up to the kidneys. PAX never get it to fit low and tight around the hips without me talking them through the process. Once they've got it right, though, the protection looks quite good.
 
rwellner98 said:
Four point belts allow submarining and severe spinal injuries. There is an STC for my plane available, but my research convinced me that the factory belts are a better choice. Now if a 5 point were available, it would be a no brainer. But it isn't...
Click to expand...

That isn't the worry. The worry is your head going forward, that is where people die that didn't have to. If you are submarining out of your belt, you aren't in a survivable crash. The worst part with head injuries isn't dying either, the worst part is living with severe brain trauma.

BAS makes a 4 point system that is an improvement over the 3, for a bunch of planes, and if you have one that isn't on the list, I bet they help you get installed. If you want 5 & 6 point sets, sure, Hooker among others have them, even have ratchet straps to really hold you in place if you want.
 
Henning said:
That isn't the worry. The worry is your head going forward, that is where people die that didn't have to.
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That is *also* a worry. But submarining is a very real thing that can make injuries worse.

The head forward - spine snap can only be prevented with helmets and straps that secure the helmet to the seat (auto racing requires this in some leagues), but if anyone is doing that in aviation it's rare enough that I've never seen it.
 
rwellner98 said:
That is *also* a worry. But submarining is a very real thing that can make injuries worse.

The head forward - spine snap can only be prevented with helmets and straps that secure the helmet to the seat (auto racing requires this in some leagues), but if anyone is doing that in aviation it's rare enough that I've never seen it.
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I walked away from an open cockpit plane upside down in oats with no injuries on a 4 point restraint. Most all the load was taken on my shoulders, I can assure you that. It's not the whiplash type injury it'll prevent, it's the contacting the panel injury.
 
MyassisDragon said:
Im not sure that can be applied to "all 4 point harnesses"

... So if the 4 point harness is anchored above the shoulders this downward force does not exist. :dunno:
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My club's Cardinal RG was originally purchased by missionaries, who installed a four point harness system. The top of the harness is attached to the main spar and hangs down from the ceiling.

It feels really secure anyway.
 
JimNtexas said:
My club's Cardinal RG was originally purchased by missionaries, who installed a four point harness system. The top of the harness is attached to the main spar and hangs down from the ceiling.

It feels really secure anyway.
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I cleaned up a couple of planes that had the BAS reel, they held up and functioned just fine. For the cost I wouldn't hesitate.
 
Henning said:
I walked away from an open cockpit plane upside down in oats with no injuries on a 4 point restraint. Most all the load was taken on my shoulders, I can assure you that. It's not the whiplash type injury it'll prevent, it's the contacting the panel injury.
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Ah, ok. Sure it will indeed prevent that. Maybe even better than a three point depending on how the impact took place.

Glad you didn't submarine in yours and get injured that way.
 
rwellner98 said:
Ah, ok. Sure it will indeed prevent that. Maybe even better than a three point depending on how the impact took place.

Glad you didn't submarine in yours and get injured that way.
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If you keep the plane under control and fly it into the crash, unless you have a really reclined seating, I just don't see the submarining, but I keep my lap belt tight except to pee.
 
+1 on the BAS 4-Point. I had them installed in my PA28-140 last march. They attach to the ceiling, so definitely above the shoulders.
 
How about rear passengers shoulder belts. My plane does not have them and I worry about that some times. How do rear passengers fare during accidents?
 
netsurfr said:
How about rear passengers shoulder belts. My plane does not have them and I worry about that some times. How do rear passengers fare during accidents?
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Not sure of the overall stats, but in 6 seaters with club seating, they have shown that the passengers in the middle facing backwards do better, regardless of belt system. In all situations three point restraint is superior to just lap belts. Lap belts alone especially in kids, do tend to ride up higher on the abdomen as opposed to around the hip bone where they are intended to sit. The possibility of internal injury is therefor increased. Where lap belts are not as bad in the back, beacause seat backs tend to be much softer and more forgiving then panels and windscreens. So the head injury reduction is significant, but not as much as the front seats.
 
Copy paste from another thread on the same subject.





Only option in my opinion, BAS with the rotary buckle.

Once you fly inerita reel belts with rotary buckles you won't look at chinsy normal belts the same way again.

Many lives have been saved by BAS belts.


http://basinc-aeromod.com/piper.php

rotary_buckle_closed.jpg


rotary_buckle_open.jpg



Read some of these, then pull out the plastic

http://basinc-aeromod.com/testimonials.php


oldShar said:
Brand wise? Or the rotary buckles? & why?

((my only real experience is when flying Grobs; but my experience is that they are just another brand of seat belt))
Click to expand...

You could buy any brand, most inerita reels are about the same price, just lots and lots of good PIREPS on the BAS, they also have a large list of approved makes and models.

The rotary buckle, it's super fast to attach and take off, one twist and you're out, no lifting or routing hoops through clasps, plus you can ditch the shoulder belts without taking the lap belt off. Just a cleaner arrangement, especially since the attachment points of the shoulder harnesses are smaller, if no one is riding shotgun the belt attachments are more out of the way then the other options IMO

Side note, all the commercial turbo props and above use the rotary buckle and inertia reel setup too.
 
James331 this is exactly the info I wanted.
 
This is a Y - type on the top. I like it because, fewer reels, fewer parts. The shouler harness terminals are permanently attached to the lower lap belt buckels, meaning the buckle never falls on the floor or out the door. I never have to go looking for the buckles either because I just grab the shoulder belts hanging behind me to find the buckles.

This by far is my favorite setup. I like the lever style latch too over buttons in cars or rotary knobs.


 
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drotto said:
Not sure of the overall stats, but in 6 seaters with club seating, they have shown that the passengers in the middle facing backwards do better, regardless of belt system. In all situations three point restraint is superior to just lap belts. Lap belts alone especially in kids, do tend to ride up higher on the abdomen as opposed to around the hip bone where they are intended to sit. The possibility of internal injury is therefor increased. Where lap belts are not as bad in the back, beacause seat backs tend to be much softer and more forgiving then panels and windscreens. So the head injury reduction is significant, but not as much as the front seats.
Click to expand...

Rear facing seats always do better regardless the circumstance as long as people are belted in.

Lack of shoulder and upper body restraint is not as much of a concern for the back seat since everything in front of them is typically soft, but it wouldn't hurt to have.
 
bnt83 said:
This is a Y - type on the top. I like it because, fewer reels, fewer parts. The shouler harness terminals are permanently attached to the lower lap belt buckels, meaning the buckle never falls on the floor or out the door. I never have to go looking for the buckles either because I just grab the shoulder belts hanging behind me to find the buckles.

This by far is my favorite setup. I like the lever style latch too over buttons in cars or rotary knobs.


Click to expand...

Yep, those are nice, secure, and convenient.
 
Connected to this, but a little different. Has anyone done the STC for the seatbelt airbags? How do those compare to a 4 point harness system?
 
James331 said:
Copy paste from another thread on the same subject.





Only option in my opinion, BAS with the rotary buckle.

Once you fly inerita reel belts with rotary buckles you won't look at chinsy normal belts the same way again.

Many lives have been saved by BAS belts.


http://basinc-aeromod.com/piper.php

rotary_buckle_closed.jpg


rotary_buckle_open.jpg



Read some of these, then pull out the plastic

http://basinc-aeromod.com/testimonials.php




You could buy any brand, most inerita reels are about the same price, just lots and lots of good PIREPS on the BAS, they also have a large list of approved makes and models.

The rotary buckle, it's super fast to attach and take off, one twist and you're out, no lifting or routing hoops through clasps, plus you can ditch the shoulder belts without taking the lap belt off. Just a cleaner arrangement, especially since the attachment points of the shoulder harnesses are smaller, if no one is riding shotgun the belt attachments are more out of the way then the other options IMO

Side note, all the commercial turbo props and above use the rotary buckle and inertia reel setup too.
Click to expand...

BAS makes a good product, and makes it easy to do business with them. I like the rotary buckle just fine, but I don't ever find myself releasing the shoulder straps, I prefer to just slip in and out. I hate fumbling with the thing trying to re buckle it in turbulence; fast and simple to slip in and out, that's the nice thing about inertial reels.
 
Henning said:
BAS makes a good product, and makes it easy to do business with them. I like the rotary buckle just fine, but I don't ever find myself releasing the shoulder straps, I prefer to just slip in and out. I hate fumbling with the thing trying to re buckle it in turbulence; fast and simple to slip in and out, that's the nice thing about inertial reels.
Click to expand...

I see the purchase price is about $1900 for the system (with the rotary buckle). What is the install cost?
 
Henning said:
BAS makes a good product, and makes it easy to do business with them. I like the rotary buckle just fine, but I don't ever find myself releasing the shoulder straps, I prefer to just slip in and out. I hate fumbling with the thing trying to re buckle it in turbulence; fast and simple to slip in and out, that's the nice thing about inertial reels.
Click to expand...

That's why I like the standard one with the shoulder straps permanently attached to the buckles. The extra $500 per seat for the rotary doesn't make sense in GA stuff.


Corporate jets with the rotary buckle have an individual reel for each shoulder strap (built into the seat). GA planes are most often a Y, with one reel attached overhead to the ceiling, if they have dual shoulder straps at all.
 
Everskyward said:
Pretty sure "Murphey" has a 4-point setup in a PA-28. Maybe she will respond here. Seems like the shoulder straps are mounted from the ceiling, not the seat itself.
Click to expand...
Yup....4point attached to a doubler on the top of the cabin frame, STC included. I did not go with the inertial reel version. Every rental I was in with the inertial reel had broken belts. I'm rather fond of low-tech that is more difficult to break. And cheaper to repair.
 
bnt83 said:
That's why I like the standard one with the shoulder straps permanently attached to the buckles. The extra $500 per seat for the rotary doesn't make sense in GA stuff.


Corporate jets with the rotary buckle have an individual reel for each shoulder strap (built into the seat). GA planes are most often a Y, with one reel attached overhead to the ceiling, if they have dual shoulder straps at all.
Click to expand...

Plus passengers who aren't acquainted have an easy time with them, and by nature pull the lap belt down to the proper position. I never have any issue with them. Typically I don't see a rotary buckle unless there is a 5-6 point system installed, then the crotch strap(s) are permanently mounted to the bottom. Then you need a rotary buckle.
 
drotto said:
I see the purchase price is about $1900 for the system (with the rotary buckle). What is the install cost?
Click to expand...

Depends on the install and shop. If the shop has done them before, they probably have it down to a few hours.
 
murphey said:
Yup....4point attached to a doubler on the top of the cabin frame, STC included. I did not go with the inertial reel version. Every rental I was in with the inertial reel had broken belts. I'm rather fond of low-tech that is more difficult to break. And cheaper to repair.
Click to expand...

I've had both and now I really appreciate the reel since I'm an amputee. Reels do fail. As far as I know almost all of the them are made by AMSAFE which seems like a pretty good company.

My BAS kits came with AMSAFE reels.
 
murphey said:
Yup....4point attached to a doubler on the top of the cabin frame, STC included. I did not go with the inertial reel version. Every rental I was in with the inertial reel had broken belts. I'm rather fond of low-tech that is more difficult to break. And cheaper to repair.
Click to expand...

I have the same ones. We are installing them right now. 9 hours in but I'm doing most of the work. The one side took me a good while and the second side I had in in about 2 hours. Glueing and stretching the headliner back in is now the pain and all the trim. Hope to have it finished tomorrow.
 
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When I was researching belts for my classic muscle car, I looked at doing 5-points, my logic being that if race cars use them, they must be safer. After talking to some folks in the know, I was advised against them for the simple reason that my car didn't have a roll cage. As a result, 5 points would not allow my head out of the way of a compressing roof (rollover, impact with object/vehicle etc). The total setup has to be looked at. To the OP, I would take broken ribs over eating my yoke or instrument panel any day. It's not a question of being injured vs not, it's a question of limiting the type and/or severity. Ribs will heal. An altimeter print on your forehead may not.
 
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