These air bags are built into the belt......
http://www.amsafe.com/products/detail.php?id=68&type=business
http://www.amsafe.com/products/detail.php?id=68&type=business
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Do you need airbags?
- Thread starter gasman
- Start date
N941WR
Legacy Member
I have never understood why people want to strap a pyrotechnic device to their chest.
In fact, in one of my cars, I replaced the steering wheel to get rid of that airbomb. Then again that car was used as a track toy. It has seatbelts very similar to our planes and since I have never seen a race car with airbombs, I’m not sure they are really needed when properly restrained.
Remember, in your car airbags are supposed a “supplemental restraint system” for those who are too dumb to put on their seatbelts.
In other words, my vote is no, don't put them in. Besides, what are you going to do if they accidently went off while taking off, flying, or landing?
In fact, in one of my cars, I replaced the steering wheel to get rid of that airbomb. Then again that car was used as a track toy. It has seatbelts very similar to our planes and since I have never seen a race car with airbombs, I’m not sure they are really needed when properly restrained.
Remember, in your car airbags are supposed a “supplemental restraint system” for those who are too dumb to put on their seatbelts.
In other words, my vote is no, don't put them in. Besides, what are you going to do if they accidently went off while taking off, flying, or landing?
craigvince
Well Known Member
Airbags
We're actually considering these airbag/seatbelts for our 2009 Skylarks. Hopefully, they'll never need to be used, but it's a great marketing point, and I think more wives would fly with them, same as the BRS parachutes. Anything to give people more comfort and peace of mind is a benefit. And who knows? It could save a life too.
I'm sure someone will install them or something similar in an RV and give some pireps.
(Just my 2 cents worth.)
We're actually considering these airbag/seatbelts for our 2009 Skylarks. Hopefully, they'll never need to be used, but it's a great marketing point, and I think more wives would fly with them, same as the BRS parachutes. Anything to give people more comfort and peace of mind is a benefit. And who knows? It could save a life too.
I'm sure someone will install them or something similar in an RV and give some pireps.
(Just my 2 cents worth.)
N941WR
Legacy Member
Exactly
I sure hope they don't! It is kind of like insurance, you only win when you lose.
(Craig, check your email.)
Some would disagree
I am not a fan of the air bag belts either, so don't read this as supporting them. I don't have them and don't want them.
Those belts have been standard equipment in Cirrus aircraft for about 3 years. At least one accident (in the European Alps) the pilot credits those belts for saving serious injury or worse for himself and his passenger.
Personally looking at the picture I think he is overstating their case, but that's his story, FWIW. To each there own.
BTW, manufacturors have more reason than just marketing. The more safety gear they install the better defense they have in the ensuing lawsuits after someone gets hurt or killed.
I am not a fan of the air bag belts either, so don't read this as supporting them. I don't have them and don't want them.
Those belts have been standard equipment in Cirrus aircraft for about 3 years. At least one accident (in the European Alps) the pilot credits those belts for saving serious injury or worse for himself and his passenger.
Personally looking at the picture I think he is overstating their case, but that's his story, FWIW. To each there own.
BTW, manufacturors have more reason than just marketing. The more safety gear they install the better defense they have in the ensuing lawsuits after someone gets hurt or killed.
cropdusterengineer
Active Member
Airbags-thumbs up!
I really don't see any negatives at all with seatbelt airbags.
When auto manufacturers started putting seat belts in cars, I'm sure there were tons of "yeah, but what if I crash and the car catches on fire and I can't get the seat belt off" guys out there.........but no one would argue the increased safety of them now. There are lots of motorcycle riders who refuse to wear helmets......for some stupid reason.
As far as inadvertant deployment, can you name one instance where this has happened in a car? (aside from Clark Griswald in the National Lampoon's Vacation movie....)
From what I've seen, they are very lightweight, not very expensive, maintenance free, comfortable to wear, and reliable. Seatbelts do a good job of restraining the body, but a lousy job of preventing head and neck injury. Thast what the airbags are designed to do.
In a crash, I like my survival chances better having them than not. Put me on the list of guys that think they are a good feature.
CDE
I really don't see any negatives at all with seatbelt airbags.
When auto manufacturers started putting seat belts in cars, I'm sure there were tons of "yeah, but what if I crash and the car catches on fire and I can't get the seat belt off" guys out there.........but no one would argue the increased safety of them now. There are lots of motorcycle riders who refuse to wear helmets......for some stupid reason.
As far as inadvertant deployment, can you name one instance where this has happened in a car? (aside from Clark Griswald in the National Lampoon's Vacation movie....)
From what I've seen, they are very lightweight, not very expensive, maintenance free, comfortable to wear, and reliable. Seatbelts do a good job of restraining the body, but a lousy job of preventing head and neck injury. Thast what the airbags are designed to do.
In a crash, I like my survival chances better having them than not. Put me on the list of guys that think they are a good feature.
CDE
N941WR
Legacy Member
Two cars that I know of and maybe more.
Mazda's Miata had a problem in 2000 I think it was. If you hit a bump just right the bags would go off. It happened to a friend who promptly stuffed their car into a tree. Oh, and on those Miatas, if both air bags went off, they would total the car because of the need to replace the windshield bow, instrument panel, and steering wheel.
The other one was the Chrysler minivans, back when they first installed airbags. The airbag controller was mounted on the floor under the driver?s seat. These usually deployed when the driver would leave his/her window down and it would rain at night. When they would get in the car and turn on the ignition, the bag would deploy.
There are a lot of other stories but those two come to mind.
Remember, airbags are "supplemental restraint systems", not the primary. They were designed to save people who wouldn't put on a seatbelt. In addition, they would do nothing for a secondary impact.
If airbags are so good, you would think race cars would have them as they have many more safety features. Yet they are not allowed by the rules.
Airbags have also hurt and killed a lot of people who should have walked away from an accident. There was a guy in Ohio who put his baby in the front seat of his pickup but forgot to turn off the right side airbag, ran a red light, bag deployed and killed his son. He was prosecuted for manslaughter. Other's have had to have facial reconstruction performed after the bags deployed in minor accidents, sending their hands into their face with enough force to break their jaws, cheekbones, etc. That's why they now tell you to keep your hands at 4 & 8 rather than 2 & 10.
As a side note, I had a friend who's wife's car was in the shop so she took his rally car to work, since it was licensed for the street, as required. It was set up for full on rally racing, complete roll cage, racing seat, six point harness, no air bags, etc. Traffic on the freeway ahead was stopped. She pulled up behind some big SUV and then some lady in a Caddy hit her from behind going 70 MPH w/o touching her brakes.
Of the three cars, she was the only one who was not hurt. The rally car was toast as the front and reat bumpers stopped where the roll cage began. She was the only out walking around when the cops and ambulance showed up. The cop stuck his head in her car and said, "Now that is something you don't see every day."
Put me down as someone who has always wares their safety belt, even when moving the car around the driveway but wishes we didn?t have to deal with these darn airbombs.
captainron
Well Known Member
Likewise, count me in on only seeing the positive aspects here.
Jamie
Well Known Member
Hehe...I'm not arguing for the air bag seatbelts one way or the other, but my cousin was involved in an incident. Of course there were mitigating circumstances.
My cousin has a thing for taking perfectly good pickup trucks and ruining any practical purpose the trucks may have previously had by lowering them to just a couple of inches off the ground. He did this very thing to a Toyota Tacoma and was cruising down a road in downtown Atlanta. He hit a pothole...and yep...you guessed it...the bumper hit the road which triggered the airbag deployment. Messed him up pretty bad and worse of all he lost forward visibility, hit his brakes and a car behind him rear-ended him.
captainron
Well Known Member
What would you call strapping on a device loaded with many gallons of highly explosive gasoline and plenty of electrical detonators, or does the fact that they're strapped to your posterior instead of your chest make the difference?
Sid Lambert
Well Known Member
I think the airbags would only help if it could keep the panel and sub-structure from reaching you. You won't be going forward if you have your belts tight. At least in a survivable crash.
wingtime
Well Known Member
I don't see a huge benifit
I don't see how those would help much in an airplane crash unless you go straight in. Sure in a car your dealing with a forward momentum such as a head on collision. But in a airplane isn't it more of an angled or vertical moment? I would think the biggest force we should be worried about is the compressive forces on our spines.
I don't see how those would help much in an airplane crash unless you go straight in. Sure in a car your dealing with a forward momentum such as a head on collision. But in a airplane isn't it more of an angled or vertical moment? I would think the biggest force we should be worried about is the compressive forces on our spines.
My understanding is that your seat belt/shoulder harness in your car will save your life; the air bag will decrease injury. There are always exceptions but a person needs to look at the balance of probabilities. I have suffered unnecessary injuries by an airbag in a minor accident, but still want them in my vehicles for when a more serious accident occurs.
If we put "race car" type roll cages into our airplanes they wouldn't carry much else but would be safer.
I don't see much downside to the airbag, but wouldn't want to be first out the gate testing this technology in my airplane!
I can see a use for the technology - but not so much as an airbag deployment system. I'm thinking more along the lines of a system to blow out or shatter the canopy on impact, to facilitate egress, even when upside down or underwater. With a little appropriate engineering you could build one or more of those airbag modules into your structure in such a way that detonation would sever the canopy hold-down structure and shove it upward and outward. That would effectively solve the "Can I bail out?" question...
Since the airbag deflates within a couple seconds, even mounting it on the dashboard facing up (with good bracing in the instrument panel) would suffice - it would toss the canopy and deflate within a few seconds, allowing you to exit the remains of the aircraft.
Just a thought...
Since the airbag deflates within a couple seconds, even mounting it on the dashboard facing up (with good bracing in the instrument panel) would suffice - it would toss the canopy and deflate within a few seconds, allowing you to exit the remains of the aircraft.
Just a thought...
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N941WR
Legacy Member
Hahahahaha...What would you call strapping on a device loaded with many gallons of highly explosive gasoline and plenty of electrical detonators, or does the fact that they're strapped to your posterior instead of your chest make the difference?
Good point
cropdusterengineer
Active Member
That is the exact opposite of my understanding of an airbag system. "Supplemental" means "in addition to".....not "in place of". They are designed to work with the seatbelts, not replace them (in cars and airplanes).
As far as secondary impact, I think the assumption is that the initial impact of an airplane crash absorbs a very large portion of the total crash energy. The airbag keeps your head, neck, and torso in the best position to survive the initial impact. The seatbelts, even the best ones money can buy, and worn correctly, will not keep your head and neck from going forward.
From what I hear, the entire event timing (from activation, to inflation, to deflation) is less than the blink of an eye.
One other feature of the aviation seatbelt airbags is that the shoulder harnesses tighten at the beginning of the crash event. That alone would increase the survivability of a crash.
CDE
w1curtis
Well Known Member
You are thinking of helicopters. Head trauma from forward impact is a major killer in otherwise surviveable small airplane crashes. This mostly in older airplanes with only a lap restraint and no shoulder restraint. Yes, with proper shoulder restraint, the need for an airbag is greatly diminished, however the pluses may outnumber the minuses.
JakeC
Member
They have just recently installed airbags in the OH-58D's I fly. I would like to think I'm safer with them installed than without. Here is a link that has some test data. Although it's not about the seat belt mounted bags it does address some of the common questions such as inadvertent deployment and water deployments.
Here is the link:
http://www.baesystems.com/BAEProd/groups/public/documents/bae_publication/bae_pdf_mps_oc_cabs.pdf
Here is the link:
http://www.baesystems.com/BAEProd/groups/public/documents/bae_publication/bae_pdf_mps_oc_cabs.pdf
Kyleag04
Active Member
Airbags
I have spent the last two years working closely with AmSafe to develop an airbag system for Air Tractor agricultural aircraft. At first, I was a little skeptical about whether airbags were needed in our aircraft. We already have designed our aircraft with remarkable crashworthiness, including a steel "roll cage" around the cockpit.
In the past two years, we have run over 12 full scale crash tests on a test sled. These crash tests were conducted at up to 26 G's, which is the maximum definition of a "survivable crash". Our development also included several safety analyses and analysis of actual crash data. My opinions of the need for airbags has been totally changed. We recently unveiled our airbag system at a convention in December and received an overwhelmingly positive response. In our testing, we determined that these airbags reduced the severity of head and neck trauma by over 95%!!!
First of all, it is important to understand that these aviation airbags are completely different that car airbags. Besides the fundamental technology involved, there are no similarities in the way the systems operate. For example, car airbags deploy toward the driver at near supersonic speeds. This alone can cause injury as described in a couple of the previous posts. However, aircraft airbags deploy AWAY from the pilot and simply fill the space between the pilot and the instrument panel. Also, the airbags are specifically designed so that when they deploy, they will not interfere with the aircraft controls or the pilots arms.
Also, the airbags are fully inflated in approximately 35 milliseconds and then deflate in less than a second. According to google, the blink of an eye takes 350 milliseconds!! Everybody worries about "inadvertant deployments" or the bags going off on accident. We did testing and analysis to prove to the FAA that the risk of inadvertant deployments was less than once for every 51 million flight hours!
If you read the accident report on this accident, you will see that this aircraft only had one operational airbag system, for the pilot seat only. The pilot walked away from the accident with a broken vertebra. The co-pilot however had a broken vertebra, severe facial injuries, and brain trauma. As was mentioned earlier, the airbags are a supplemental safety device that reduces the severity of head and upper torso injuries.
Do what you like with this info, but it has been an eye-opening experience for me.
I have spent the last two years working closely with AmSafe to develop an airbag system for Air Tractor agricultural aircraft. At first, I was a little skeptical about whether airbags were needed in our aircraft. We already have designed our aircraft with remarkable crashworthiness, including a steel "roll cage" around the cockpit.
In the past two years, we have run over 12 full scale crash tests on a test sled. These crash tests were conducted at up to 26 G's, which is the maximum definition of a "survivable crash". Our development also included several safety analyses and analysis of actual crash data. My opinions of the need for airbags has been totally changed. We recently unveiled our airbag system at a convention in December and received an overwhelmingly positive response. In our testing, we determined that these airbags reduced the severity of head and neck trauma by over 95%!!!
First of all, it is important to understand that these aviation airbags are completely different that car airbags. Besides the fundamental technology involved, there are no similarities in the way the systems operate. For example, car airbags deploy toward the driver at near supersonic speeds. This alone can cause injury as described in a couple of the previous posts. However, aircraft airbags deploy AWAY from the pilot and simply fill the space between the pilot and the instrument panel. Also, the airbags are specifically designed so that when they deploy, they will not interfere with the aircraft controls or the pilots arms.
Also, the airbags are fully inflated in approximately 35 milliseconds and then deflate in less than a second. According to google, the blink of an eye takes 350 milliseconds!! Everybody worries about "inadvertant deployments" or the bags going off on accident. We did testing and analysis to prove to the FAA that the risk of inadvertant deployments was less than once for every 51 million flight hours!
If you read the accident report on this accident, you will see that this aircraft only had one operational airbag system, for the pilot seat only. The pilot walked away from the accident with a broken vertebra. The co-pilot however had a broken vertebra, severe facial injuries, and brain trauma. As was mentioned earlier, the airbags are a supplemental safety device that reduces the severity of head and upper torso injuries.
Do what you like with this info, but it has been an eye-opening experience for me.
Kyleag04
Active Member
An interesting picture
Here is an interesting picture from our testing. This is a 26 G test. On the left is an occupant wearing our standard aircraft seat belt and shoulder harnesses. On the right is exactly the same except that the airbags have been installed on top of the stock restraints.
You never realize how much the belts stretch until you see them under the high speed camera.
Notice how the airbags cradle the occupant's head and keep it from traveling forward or side to side. The airbags also keep the occupant's head and spine inline for better protection against damage from forward and even vertical loads.
Here is an interesting picture from our testing. This is a 26 G test. On the left is an occupant wearing our standard aircraft seat belt and shoulder harnesses. On the right is exactly the same except that the airbags have been installed on top of the stock restraints.
You never realize how much the belts stretch until you see them under the high speed camera.
Notice how the airbags cradle the occupant's head and keep it from traveling forward or side to side. The airbags also keep the occupant's head and spine inline for better protection against damage from forward and even vertical loads.
osxuser
Well Known Member
In cars, airbags are designed to ONLY go off if the seat belts are buckled. They saved my sisters life, saved me thousands on medical bills when I got in my last car accident. That said:
I don't think they belong in airplanes however. If you are in a bad enough crash in an AIRPLANE to need an airbag (over a 4-point harness) I think the chances of it helping are slim.
I don't think they belong in airplanes however. If you are in a bad enough crash in an AIRPLANE to need an airbag (over a 4-point harness) I think the chances of it helping are slim.
Compelling photo
That is a heck of a compelling photo. A large source of injury in aircraft accidents is head trauma associated with hitting panels, yokes (not that we have that problem) and other things. That bag in front of your face is a awesome way to provide protection for your head.
That is a heck of a compelling photo. A large source of injury in aircraft accidents is head trauma associated with hitting panels, yokes (not that we have that problem) and other things. That bag in front of your face is a awesome way to provide protection for your head.
Here is an interesting picture from our testing. This is a 26 G test. On the left is an occupant wearing our standard aircraft seat belt and shoulder harnesses. On the right is exactly the same except that the airbags have been installed on top of the stock restraints.
You never realize how much the belts stretch until you see them under the high speed camera.
Notice how the airbags cradle the occupant's head and keep it from traveling forward or side to side. The airbags also keep the occupant's head and spine inline for better protection against damage from forward and even vertical loads.
cropdusterengineer
Active Member
airbags
Awesome info Kyle! By the way, change your sig to "wing kit on the shop floor".
CDE
Awesome info Kyle! By the way, change your sig to "wing kit on the shop floor".
CDE
pierre smith
Well Known Member
Remember....
.....Dale Earnhardt and his accident?
Regards,
.....Dale Earnhardt and his accident?
Regards,
Kyleag04
Active Member
Good question. Usually the way AmSafe works is that they work with the airplane manufacturer to design an airbag system specifically for the cockpit of that aircraft.
Like I said before, the airbags must be designed so that when they deploy they do not interfere with the flight controls. To do this, we had to supply a donor fuselage frame (cockpit section) that could be crash tested at the AmSafe facility.
My thinking is that AmSafe would probably be willing to develop the airbags, but would need support from Van's to get the job done.
w1curtis
Well Known Member
You can get them here from Aerocraft parts. $4,350 for a set of two 3 point restrains with airbag incorporated into lap belt. Four point systems are popular in RVs because the keep you in the seat at unusual attitudes but 3 point systems are actually more effective than 4 (but not 5) point systems in a forward collision. There is no tendancy for the lap belt to ride up in a 3 point system as it can with a 4 four point system.
Installation (Lancair) Instructions:
http://www.aerocraftparts.com/images/pdfs/AAIR-Appendex-A.pdf
http://www.aerocraftparts.com/images/pdfs/AAIR.pdf
w1curtis
Well Known Member
Extensively--See above picture and Amsafe web site.
A six point seat belt in a Normal category 172 is a bit overkill--even in a utility category aircraft. 4, 5 and 6 point make sense in RV-3, 6, 7 and 8, but not so much in the RV-9, 10 and 12.
Thanks Kyle!
Kyle, Thanks for the data and background from someone who has studied and evaluated this application. This forum amazining in that there always seems to be someone here that is a REAL expert on most topics.
Did they let you go for a ride on the crash sled? The dummy on the left looks like he might need a good chiropractor!
Kyle, Thanks for the data and background from someone who has studied and evaluated this application. This forum amazining in that there always seems to be someone here that is a REAL expert on most topics.
Did they let you go for a ride on the crash sled? The dummy on the left looks like he might need a good chiropractor!
John Clark
Well Known Member
Basal skull fracture
Pierre, here is an interesting discussion: http://www.motorsport.com/magazine/feature.asp?C=Special&D=2001-02-21
John Clark
RV8 N18U "Sunshine"
KSBA
Pierre, here is an interesting discussion: http://www.motorsport.com/magazine/feature.asp?C=Special&D=2001-02-21
John Clark
RV8 N18U "Sunshine"
KSBA
Norman CYYJ
Well Known Member
If you are moving forward fast enough air bags aren't going to help you. They may save your pretty face but your brain and internal organs are still going forward and they come to a sudden stop and turn to mush anyways.
N941WR
Legacy Member
True but that's why you really need a sub-strap when using a four point system. They hold the lap belt down and keep it from ridding up.
With three point systems, they either have auto tensioners or people just seem to tighten the lap belt first then the shoulder belt.
With four point systems, people tend to tighten the shoulder belts first, then the lap belts. That sequence pulls the lap belt up across the stomach. This is backwards, you want that lap belt down around your hips, not across your stomach.
I will argue with you on this point. The sub strap is primarily thought of a good thing for acro but in the event of an accident, you want that sub strap to hold the lap belt down across your hips, regardless of which model RV you fly.
Here's the deal...
If the lap belt rides up over the hips during an accident, it will damage the internal organs. You may survive the initial impact but will probably die a few days later from these injuries. Maybe one of the doctors on this forum can elaborate.
In my track car, the SCCA mandated 3" six point harness. Each shoulder harness had its own attach point as did the lap belts. The sub strap could be 1" but required two attach points.
The standard harness is an RV is really a three point harness as both shoulder straps go to one point. With a sub strap, it is really just a four point harness.
w1curtis
Well Known Member
Bill,
The problem with anything above a 3 point system for a cross country non-aerobatic airplane is that they are NOT very comfortable for extended periods and normal passenger interaction. Even the 4 point retracting system in the new Cirrus are not very comfortable and tend to ride up to the stomach. On extended flights, I find myself constantly pulling them tight to bring them back down to my hips. Imagine if you had to strap on a 5 point seat belt on an airline trip. People would unstrap themselves as soon as they could, potentially incurring more injuries due to unexpected turbulence than with the simple lap belt which is not so obtrusive.
The best multi-point system is totally ineffective if the passengers are not wearing it because they are uncomfortable. I think I conceded the fact that the 5 point (crotch strap) is safer than the 3 point but the 3 point is the best compromise between safety and comfort and is better than than a 4 point system without a crotch strap.
There are some picture on the web of toddlers riding in RVs with the 4 point system where the lap belt portion is riding up roughly across their stomachs almost up to their chest. This can't be safe under any situation.
I would not put a 3 point system in a 6, 7 or 8 but in my 10 (or if I built a 9) I'll have 3 point retracting belts all around. My rational is that I won't be doing aerobatics; they are simpler to use by passengers; they are safer than the standard 4 point belts where they are typically needed; and they will be more comfortable so not to encourage passengers to remove or loosen them.
The problem with anything above a 3 point system for a cross country non-aerobatic airplane is that they are NOT very comfortable for extended periods and normal passenger interaction. Even the 4 point retracting system in the new Cirrus are not very comfortable and tend to ride up to the stomach. On extended flights, I find myself constantly pulling them tight to bring them back down to my hips. Imagine if you had to strap on a 5 point seat belt on an airline trip. People would unstrap themselves as soon as they could, potentially incurring more injuries due to unexpected turbulence than with the simple lap belt which is not so obtrusive.
The best multi-point system is totally ineffective if the passengers are not wearing it because they are uncomfortable. I think I conceded the fact that the 5 point (crotch strap) is safer than the 3 point but the 3 point is the best compromise between safety and comfort and is better than than a 4 point system without a crotch strap.
There are some picture on the web of toddlers riding in RVs with the 4 point system where the lap belt portion is riding up roughly across their stomachs almost up to their chest. This can't be safe under any situation.
I would not put a 3 point system in a 6, 7 or 8 but in my 10 (or if I built a 9) I'll have 3 point retracting belts all around. My rational is that I won't be doing aerobatics; they are simpler to use by passengers; they are safer than the standard 4 point belts where they are typically needed; and they will be more comfortable so not to encourage passengers to remove or loosen them.
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w1curtis
Well Known Member
Norman,
This argument is spurious. The fact is that many NTSB reports cite blunt force head trauma as a cause of death in otherwise survivable crashes. If you face is "still pretty" chances are there is no blunt force head trauma. This is why the FAA allowed Cessna and other manufacturers to offer easy additions of shoulder straps to aircraft that previously had only lap restraints.
It is very difficult to receive fatal head trauma if there is no damage to the skull. If the head moves with the impact, even though it does not impact anything, there could be damage to the neck and spine--this is where the air bag comes in. But If the body is held in place and does not impact anything, the only typical internal injury that results is rupture of the spleen due to it how it is attached internally. Keeping the body from impacting anything, by whatever means, even if there is a high negative G, is a good thing.
Norman CYYJ
Well Known Member
Blunt force damage will be prevented but as I said before if you are going fast enough and your body comes to a complete stop abruptly there is nothing going to stop the internal organs from continuing to go forward and tearing from their mounts or the brain from slamming forward. Which in the end does you in. I have cleaned up too many accidents with no apparent damage to the body only to find thru reports that the innards are destroyed.
Well, yeah - if you hit a mountain at 150 mph there's no safety equipment in the world that will save you. Not sure that's an agrument for or against any safety device. If the argument is that your brain turns to mush in a 100 G impact, then why wear seatbelts at all? The answer is, as mentioned before, decelleration less than 26 G's or so is survivable, if you are not thrown against the panel, and you're head / neck / spine are restrained and kept aligned.
Kyleag04
Active Member
Survivable vs. Unsurvivable
As JDRhodes says, you have differentiate between a survivable and an unsurvivable deceleration. The FAA places this differentiation at 26G's. Anything above 26G's and the likelihood of surviving drops off sharply whether you have any safety systems installed or not.
At decelerations less than 26G's, the event is expected to be survivable assuming your body is properly restrained. At these conditions, all of your internal organs are still where they're supposed to be and functioning properly as long as there is no external impacts (blunt force traumas or penetrating traumas). As w1curtis and N941WR said above, if the seat belt is not located properly across your hips, the belt can provide this blunt force trauma that can cause fatal injuries.
Now, assuming that you have a properly adjusted and properly located seatbelt system, your torso will be properly restrained and you should not receive any fatal torso injuries.
However, your neck has a 8 lb mass sitting on top of it, with nothing restraining it. In the real world, when your head flings forward in a 26G stop, it actually endures a whiplash effect that imposes more than 26G's. Our testing showed this to be around 110 G's!! So, that is 880 lbs of weight (more if you are wearing a helmet) pulling on a very sensitive spine. That can't be good. This can result in the type of basal skull fracture that killed Dale Earnhardt.
Now, with the airbag system that we have designed for Air Tractors, the airbags inflate underneath your chin and keeps your head from whipping forward, reducing the acceleration of your head down to about 32 G's. Using the head injury (HIC) formulas that the FAA uses to determine the severity of head injuries, the airbags reduce the severity of head injuries by 95%.
As JDRhodes says, you have differentiate between a survivable and an unsurvivable deceleration. The FAA places this differentiation at 26G's. Anything above 26G's and the likelihood of surviving drops off sharply whether you have any safety systems installed or not.
At decelerations less than 26G's, the event is expected to be survivable assuming your body is properly restrained. At these conditions, all of your internal organs are still where they're supposed to be and functioning properly as long as there is no external impacts (blunt force traumas or penetrating traumas). As w1curtis and N941WR said above, if the seat belt is not located properly across your hips, the belt can provide this blunt force trauma that can cause fatal injuries.
Now, assuming that you have a properly adjusted and properly located seatbelt system, your torso will be properly restrained and you should not receive any fatal torso injuries.
However, your neck has a 8 lb mass sitting on top of it, with nothing restraining it. In the real world, when your head flings forward in a 26G stop, it actually endures a whiplash effect that imposes more than 26G's. Our testing showed this to be around 110 G's!! So, that is 880 lbs of weight (more if you are wearing a helmet) pulling on a very sensitive spine. That can't be good. This can result in the type of basal skull fracture that killed Dale Earnhardt.
Now, with the airbag system that we have designed for Air Tractors, the airbags inflate underneath your chin and keeps your head from whipping forward, reducing the acceleration of your head down to about 32 G's. Using the head injury (HIC) formulas that the FAA uses to determine the severity of head injuries, the airbags reduce the severity of head injuries by 95%.
So let's look at it this way: You hit a mountain at speed X with no protection and you die. So you add a lap belt and you survive at X, but not X+Y. So you add a shoulder harness & you can survive X+Y, but not X + Z. Add an airbag & you survive X+Z, but not X + A, because X + A is not survivable with any known safety equipment. Is that an argument for not installing the airbag? I think not.
To me the only valid arguments for not using the airbag, if it can be installed in an RV is price (we all make cost benefit analyses subjectively all the time, factoring in probabilities), space considerations and weight.
Norman CYYJ
Well Known Member
It is quite interesting, how people read things. I said "IF you were going fast enough". I am in favour of any safety item that will prevent injuries.
Kyleag04
Active Member
Norman, you are absolutely right. I didn't mean to take anything away from your comments.
In my spare time, I am a certified first responder and fire fighter. I have seen a wide variety of car accidents and it comes to a point (in a head on collision for instance) where no safety feature in the world can help you.
In my spare time, I am a certified first responder and fire fighter. I have seen a wide variety of car accidents and it comes to a point (in a head on collision for instance) where no safety feature in the world can help you.
the_other_dougreeves
Well Known Member
Yes, and don't forget carbon fiber front/side/rear crush structures, fuel cells, helmets with HANS (that's going to do wonders for looking for traffic in the pattern), footbox structures, crash testing of individual structures as well as the entire vehicle, teathers for heavy parts (e.g., engine), CO2 / halon fire bottles, etc.
I agree, there won't be much room or useful load left, either in the airplane or the wallet.
TODR
I'm reviving this because I noticed Cubcrafters has lap deployed airbags. They have control stick instead of wheel, so an RV application must be possible?
IIRC the US Army is the motivating force for the original airbag....in helicopters. These crash in very complex and imaginative ways. Later the technology was simplified and added to cars.
Airbags really are intended for aircraft from the git-go.
I'm having the time of my life building my RV-8. Now I'm getting close to flying and Safety of Flight issues are comming to my attention. Like training, seatbelts, fire extinguisher, canopy egress, maybe a parachute....
The Ballistic Parachute looks impractical and heavy, but these seat belt air bags are much more practical, although they address a different crash type.
About application:
So you're starving; a guy offers you a slice of bread. You turn him down because it won't measure up to your calorific requirement for the day?
I say: Any beats none.
What we are talking about here is risk reduction. I chose an RV-8 because it has a comparatively low landing speed. 60 MPH is about as fast as I want to land. The crash mortality rate goes up exponentially with crash speed. I couldn't bring myself to build one of those fast glass ships that lands so fast.
Also, the same for crash angle. The more horizontally you crash the better your chances of survival. Those crashes where all the wreckage fits within the wing span? Not so much.
So you are forced to make an off field landing. You could walk away if a field or short strip of road or something let you get to the ground horizontally, because even if you could not get stopped, you could get slowed to the point that the 'belts and bags' protect the most important part (you).
IIRC the US Army is the motivating force for the original airbag....in helicopters. These crash in very complex and imaginative ways. Later the technology was simplified and added to cars.
Airbags really are intended for aircraft from the git-go.
I'm having the time of my life building my RV-8. Now I'm getting close to flying and Safety of Flight issues are comming to my attention. Like training, seatbelts, fire extinguisher, canopy egress, maybe a parachute....
The Ballistic Parachute looks impractical and heavy, but these seat belt air bags are much more practical, although they address a different crash type.
About application:
So you're starving; a guy offers you a slice of bread. You turn him down because it won't measure up to your calorific requirement for the day?
I say: Any beats none.
What we are talking about here is risk reduction. I chose an RV-8 because it has a comparatively low landing speed. 60 MPH is about as fast as I want to land. The crash mortality rate goes up exponentially with crash speed. I couldn't bring myself to build one of those fast glass ships that lands so fast.
Also, the same for crash angle. The more horizontally you crash the better your chances of survival. Those crashes where all the wreckage fits within the wing span? Not so much.
So you are forced to make an off field landing. You could walk away if a field or short strip of road or something let you get to the ground horizontally, because even if you could not get stopped, you could get slowed to the point that the 'belts and bags' protect the most important part (you).
David Paule
Well Known Member
Next best thing to an ejection seat.
Incidentally, they are optional - the airbag belt, that is - on new Cessna 172s. I saw one a few years ago with them.
Incidentally, they are optional - the airbag belt, that is - on new Cessna 172s. I saw one a few years ago with them.
pierre smith
Well Known Member
We also enjoy....
....a gradual, energy-absorbing crumpling from front to rear in these RV's. It is amazing how much energy is absorbed by the structure deforming on impact, reducing the net frontal G-loads the occupants receive.
These belts were shown at Reno, as Kyle pointed out, and attracted a lot of positive comments from the hundreds of ag-pilots there. Our work involves dodging cars, trees, buildings, 18 wheelers, irrigation pivot systems, fences, deer, wind-powered generators and so many other obstacles, at 140 MPH.
Even though it's 16' from my spinner to my seat...a lot of crumple zone, I'm gonna retrofit my Air Tractor.
Best,
....a gradual, energy-absorbing crumpling from front to rear in these RV's. It is amazing how much energy is absorbed by the structure deforming on impact, reducing the net frontal G-loads the occupants receive.
These belts were shown at Reno, as Kyle pointed out, and attracted a lot of positive comments from the hundreds of ag-pilots there. Our work involves dodging cars, trees, buildings, 18 wheelers, irrigation pivot systems, fences, deer, wind-powered generators and so many other obstacles, at 140 MPH.
Even though it's 16' from my spinner to my seat...a lot of crumple zone, I'm gonna retrofit my Air Tractor.
Best,
Kyleag04
Active Member
Bill,
The AmSafe airbag system (as installed in Air Tractor aircraft) are composed of 4 main parts: 1) the "trigger" mechanism, 2) the electrical cabling, 3) the inflator(s), and 4) the airbag/shoulder harness assembly.
The trigger mechanism is a small, sealed, self-contained box (approx. 2" x 3" x 6") that mounts to some rigid structure. This box houses a battery and the "crash sensor". Fundamentally, this crash sensor is a weight on a shaft attached to a spring. During a sudden deceleration (aka "crash") this weight slides forward triggering a pair of switches that trigger the airbags to deploy. (Note: Don't get me wrong, there is a lot more to it than that. This is a much simplified explanation. There are several safety features, the mass of the weight and the stiffness of the spring are very carefully selected, etc...)
The electrical cabling connects the box to the inflators. This is standard shielded cable with a protective sleeve around it to help prevent damage to the cabling during a crash. This cabling contains a diagnostic connector that can be used to inspect the system without removing it from the airplane.
The inflators are basically identical to car airbag inflators. The size of the inflator and the mixture of gasses they are filled with (Argon and Helium in the case of the Air Tractors) varies depending on the particular application.
The airbag/shoulder harness assembly contains airbags incorporated around a standard shoulder harness. There are hoses that attach to the inflators.
It should be noted that this system is not connected to ship's electrical power at all. It has its own battery and is completely independent, so the system would not be affected in any way by loss of electrical power in the airplane.
Pilot135pd
Well Known Member
So 12 years later, how many have actually installed airbags in their aircraft and what's the consensus now? I'm researching this to see if I install the:
AmSafe airbags https://www.aircraftspruce.com/catalog/appages/amsafe_05-22028.php?clickkey=113305
or a 5 point harness. https://www.daymotorsports.com/shop...mall-buckle-latch-link-pro-harness/RQP-811001
AmSafe airbags https://www.aircraftspruce.com/catalog/appages/amsafe_05-22028.php?clickkey=113305
or a 5 point harness. https://www.daymotorsports.com/shop...mall-buckle-latch-link-pro-harness/RQP-811001
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