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Safety Question - Seats with Headrests

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Riggerrob

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Dear Bigshu,
The type of foam can radically improve your chances of surviving a crash.
Even back in the 1970s, Ladzlo Pazmany recommended installing styro-foam seat cushions that collapse slightly quicker than your spine. Think of those cushions the same as motorcycle helmets: good for one crash!

NASA developed some fancy foams to cushion impacts for astronauts.
Oregon Aero will cheerfully sell you a variety of stock seat cushions made of NASA's fancy foams. For a few extra dollars, they will sew custom cushions for your airplane, or even re-upholster your entire cockpit.
Kitplanes and Sport Aviation magazines have also published a few articles about sewing your won sear cushions.

Seat cushions are like parachutes ... the earlier you decide, the more likely you can install - moderately priced - stock seating.
 

pictsidhe

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Big box styrofoam looks excellent as a crash energy absorber. I'm going to put as much as I can under my seat. Extra styro pads will raise the seat height for shorter people. Light enough to carry onboard.
 

D Hillberg

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Racing seats are not designed for typical aircraft impacts. Cars don't fall from the sky.
You are wrong on all counts. Racing seats are designed for supporting the driver in impacts you'll never see in an aircraft. Father raced all his life as with my brothers, And all of us worked in aviation. Big difference.
Some aircraft have less under your back & butt then even the typical production automobile.
An old Grumman had plywood for seat bottoms... A Robinson is foam and a .0too thin sheet aluminum.
 

BBerson

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Racing seats are designed for supporting the driver in impacts you'll never see in an aircraft. F
That's why they are not ideal for aircraft. Aircraft need seats engineered and designed for aircraft with progressive deformation on the bottom. The seat belts restrain the body in position. Study military helicopter seats. I am not suggesting getting old inferior airplane seats.
 

PagoBay

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Big box styrofoam looks excellent as a crash energy absorber. I'm going to put as much as I can under my seat. Extra styro pads will raise the seat height for shorter people. Light enough to carry onboard.
Can you clarify what you mean by "big box styrofoam", an example? What is the thickness you are considering for under the seat?

Cirrus SR22 seats have full height head protection and also crash energy absorption. So you are in good company with the concept.
From the owner manual: Do not kneel or stand on the seats. The seat bottoms have an integral aluminum honeycomb core designed to crush under impact to absorb downward loads.
 

rv7charlie

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I can't imagine owning a low wing a/c that was *designed* to keep me from standing/kneeling on the seats. Of course, I can't imagine spending SR22 money on an a/c, either...

I doubt that using random styrofoam will provide any meaningful controlled crush in a crash. Low density rigid foam is used as structure in wings; it seems unlikely to provide crush protection in a crash. I've got kludged booster wedges made of rigid urethane foam (roughly the same density as styrofoam) under the Temperfoam seats in my RV6, and I stand/kneel on them all the time while doing maintenance, accessing the baggage area, etc.

Temperfoam, Sunmate, and the various post-patent knockoffs (if you're careful) will all provide proven protection as long as the density layers are engineered correctly, and as a bonus, provide a cushion that you can tolerate sitting on for more than a half hour at a time. Only downside is that the foam isn't light. Or particularly cheap. Van's A/C ships Temperfoam type front seat cushions with their RV10 kits, specifically for crash protection.

Man, we are a loong way from headrests... ;-)
 

pictsidhe

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Can you clarify what you mean by "big box styrofoam", an example? What is the thickness you are considering for under the seat?
25psi XPS insulation sheets. The crush strength is a bit higher than optimum, but that can be fixed by drilling it. I'd like to get 2" under my butt. Normal height people can fit extra pieces in for seat height adjustment. It absorbs energy pretty well. Drop a concrete block on it and see how far it doesn't bounce. There is better stuff, such as some divinycell grades, but at a far higher price and tricky to find. This is for an affordable ultralight, aluminium honeycomb is not in the financial budget and temperfoam is not in the weight budget. XPS is light, cheap and works fairly well.
 

Pilot-34

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I took a look at a lot of seats on the Internet just now and not one of them seem to be expensive in comparison to what I value my life at.....
 

Pops

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High back seats in the VW off-road buggie that I am building. Not so worried about weight as in an airplane. Yes, I would like to have high back seats in my airplane. Weight is the enemy.
 

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Pilot-34

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Pops you’re right about the weight thing I flying a Cessna XP with the ultimate luxury full leather interior
And this thread has me thinking about the possibility of at least temporarily replacing the seas with high back low weight seating.
Of course I’m sure the STC if there is one will cost more than the seats themselves I guess It’s time to hook around on Google and see what I can find
 

Pilot-34

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Thinking about all my guy in back time in Boeing’s it occurs to me all the commercial airliner seats are Highback . let’s face it if the airlines thought that they could save a buck or a pound the seats would all be stools !
that in itself is a powerful argument for high-back seat
 

rv7charlie

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FAA *requires* shoulder straps in any new GA a/c build, as is required for road vehicles. Where are they in airliners? If the airlines were focused on safety (beyond that forced on them by FAA), they'd have the seats facing to the rear (and shoulder harness), like military transport often is. My money is on headrests to sell tickets (pretense of passenger comfort).
 

Pops

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Pilot-34 ---- My daughter and her husband had a 1963 Cessna 172 ( manual flaps) Lyc- 360, 180 hp conversion, fixed pitch prop ( saved a lot of weight and expense with very little hit on climb and cruise), STC for 200 lb higher GW, battery moved to behind the baggage compartment. Panel to dream about with autopilot coupled to everything. I flew it a lot and loved that C-172.
 

pictsidhe

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FAA *requires* shoulder straps in any new GA a/c build, as is required for road vehicles. Where are they in airliners? If the airlines were focused on safety (beyond that forced on them by FAA), they'd have the seats facing to the rear (and shoulder harness), like military transport often is. My money is on headrests to sell tickets (pretense of passenger comfort).
Airliners are actually very safe. Preventing passengers from being bounced out if their seats by turbulence or shear is by far the most common need for belts.
 

rv7charlie

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The interwebs are cat herding at its finest. ;-)

My statement related to whether airline seats had headrests for safety, or for "comfort". It had nothing whatsoever to do with the airline's safety record (other than the fact that it's forced on them by FAA & counterparts around the world).
 
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wsimpso1

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Another risk is sliding backwards after a forced landing.

For example, a dozen years ago, I was riding in the back of a Beechcraft King Air when both engines quit. The pilot was professional enough to belly-land (wheels up) a kilometre short of the asphalt runway. We touched down with wings level and close to the stall speed. Initially, we slid forward smoothly, but a wing struck a dike, flipping us to slide backwards.
Later that evening, the emergency room doctor diagnosed me with two damaged spinal discs in my neck, etc. My neck never completely healed.

Lesson learned, seat-belts and head-rests would probably have reduced injuries.
There are a number of ways we could get a collision from aft.

I urge anyone thinking about these issues to look into the relative frequencies and severities of each of the crash modes and make choices based upon that analysis. I personally would go after the big frequency high severity modes first, and put in less weight and effort in the lower frequency and/or severity modes.

I personally have chosen to protect from the FAA standard 19g and 26g cases, not just for the belt mounts, but for the seats and cockpit, then covered the rollover case. Other folks may choose to go further...

Billski
 

pictsidhe

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The interwebs are cat herding at its finest. ;-)

My statement related to whether airline seats had headrests for safety, or for "comfort". It had nothing whatsoever to do with the airline's safety record (other than the fact that its forced on them by FAA & counterparts around the world).
It can't be comfort. Many of those dang 'headrests' dig into my shoulder blades. They aren't removeable either, at least not with anything I can carry on... :mad:

I am attempting to meet as much as I can of part23 with my part103. Weight means some stuff will get skimped on to a greater or lesser extent. I'm not having sleepless nights when I settle on 80-90% of some spec. Especially if I am doing better than most Ultralights. For a part23, I'd probably be a bit less skimpy.
 
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