Neck whiplash prevention system
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Neck whiplash prevention system
I found myself recently researching the restraint systems within ejection seats and was amazed to find little in the way of neck whiplash prevention in most modern ejection seat designs such as the ACES-II. There have been many proposed ideas for one but most involve some sort of inflatable device around the head which I reckon is the main reason why such a device has not been implemented.
For my final year project in uni I've been thinking about other methods, such as an inertial reel system that acts like a seat belt attached by wire or cable to the pilots helmet. The reel would have to be innactive during flight operation to allow the pilot freedom of movement.
It could also work by electric motors in the back of the chair.
Further integration of a device such as this could have the electronics from the helmet being fed through the same wire, however this may make this a little more complex.
Just woderin what people think of this idea....
For my final year project in uni I've been thinking about other methods, such as an inertial reel system that acts like a seat belt attached by wire or cable to the pilots helmet. The reel would have to be innactive during flight operation to allow the pilot freedom of movement.
It could also work by electric motors in the back of the chair.
Further integration of a device such as this could have the electronics from the helmet being fed through the same wire, however this may make this a little more complex.
Just woderin what people think of this idea....
There is a system developing for motorcycle riders that has an inflatable collar,triggered by electronics, as car airbags are,and it has been used successfully in racing in one of the MotoGPs. Try the `motorcyclenews` web.
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I think the system in F1, where it attaches to the helmet and is a collar would be preferable to a system that connected the helmet to the seat, if that portion of the man-seat separation didn't work correctly you could end up with a very long neck.
The F1 HANS thingy is a collar that sits on the shoulders and attaches to the helmet - it is held in place by the tension from the shoulder harness so when the pilot unstraps the HANS goes with him/her. The F1 drivers say once they got used to it they now no longer notice it, I'm not sure about how much it restricts vison when turning the head though.
I say we all move to ucav's anyway. problem solved.
The F1 HANS thingy is a collar that sits on the shoulders and attaches to the helmet - it is held in place by the tension from the shoulder harness so when the pilot unstraps the HANS goes with him/her. The F1 drivers say once they got used to it they now no longer notice it, I'm not sure about how much it restricts vison when turning the head though.
I say we all move to ucav's anyway. problem solved.
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The majority of injuries in an ejection tend to be spinal, typically compression injuries caused by the upwards force through the seat. If the spine is a little out of alignment the result can be as severe as crushed vertebrae. I can't really see where the whiplash would occur.
FWIW I wouldn't really be comfortable strapping in with my head attached to the seat by a restraint system. I'd rather be responsible for putting it in the correct position myself!
Blunty
FWIW I wouldn't really be comfortable strapping in with my head attached to the seat by a restraint system. I'd rather be responsible for putting it in the correct position myself!
Blunty
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BluntM8,
As you say , the bigger problem in ejection in most cases is vertical rather than lateral acceleration.
Both the upper and lower initial British ejection seat handle positions were designed to make the occupant adopt the right spinal posture on ejection.
The upper handle position , although good, presented some problems, including that under high positive 'g' situations the user might not be able to raise his ( in those days) arms above his head. Also, by possibly pulling the posterior off the seat in the initial tug, there was a danger of the seat accelerating enormously, prior to transmitting the load to the occupant. The lower handle is quicker to grab, whatever the circumstances.
To this one can add the problems of the intervertebral discs, which , if not pre-compressed, act as essential shock absorbers during ejection. These, incidentally, deteriorate as we age and we shrink in stature accordingly.
Some older seat designs , with the shoulder strap anchorages low on the seat, actually compressed the spine in normal use, decreasing the chances of avoiding spinal injury during initial ejection.
In any event, ejection pushes the spine close to the limits of physical tolerance, for perfectly justifiable reasons.
Apart from industry, we owe a lot to the work of many in the R.A.F. over the years, including those at the Institute of Aviation Medicine at Farnborough such as Tony Barwood, Peter Howard and Jim Fitzgerald amongst others in the past, for giving aircrew the best chance possible once choosing to pull the handle.
As you say , the bigger problem in ejection in most cases is vertical rather than lateral acceleration.
Both the upper and lower initial British ejection seat handle positions were designed to make the occupant adopt the right spinal posture on ejection.
The upper handle position , although good, presented some problems, including that under high positive 'g' situations the user might not be able to raise his ( in those days) arms above his head. Also, by possibly pulling the posterior off the seat in the initial tug, there was a danger of the seat accelerating enormously, prior to transmitting the load to the occupant. The lower handle is quicker to grab, whatever the circumstances.
To this one can add the problems of the intervertebral discs, which , if not pre-compressed, act as essential shock absorbers during ejection. These, incidentally, deteriorate as we age and we shrink in stature accordingly.
Some older seat designs , with the shoulder strap anchorages low on the seat, actually compressed the spine in normal use, decreasing the chances of avoiding spinal injury during initial ejection.
In any event, ejection pushes the spine close to the limits of physical tolerance, for perfectly justifiable reasons.
Apart from industry, we owe a lot to the work of many in the R.A.F. over the years, including those at the Institute of Aviation Medicine at Farnborough such as Tony Barwood, Peter Howard and Jim Fitzgerald amongst others in the past, for giving aircrew the best chance possible once choosing to pull the handle.
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The majority of injuries in an ejection tend to be spinal, typically compression injuries caused by the upwards force through the seat. If the spine is a little out of alignment the result can be as severe as crushed vertebrae. I can't really see where the whiplash would occur.
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I agree, A friend of mine has a book on 'Aviation pathology'
And in that book it explains that in the 1960's alot of FJ crew were fatally injured ejecting from their mounts, The early MB ejection seats were not set at the right settings for a safe & succesful ejection.
The aircrews were being crushed against the aircraft during the ejection sequence.
The book contains 'graphical' images of the aircrew's fatal injuries, Spinal was the most common.
Thankfully MB realised the error and after that time the MB has saved thousands of lives.
The majority of injuries in an ejection tend to be spinal, typically compression injuries caused by the upwards force through the seat. If the spine is a little out of alignment the result can be as severe as crushed vertebrae. I can't really see where the whiplash would occur.
Reply
I agree, A friend of mine has a book on 'Aviation pathology'
And in that book it explains that in the 1960's alot of FJ crew were fatally injured ejecting from their mounts, The early MB ejection seats were not set at the right settings for a safe & succesful ejection.
The aircrews were being crushed against the aircraft during the ejection sequence.
The book contains 'graphical' images of the aircrew's fatal injuries, Spinal was the most common.
Thankfully MB realised the error and after that time the MB has saved thousands of lives.
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Whiplash injuries result from sudden rearward movement of the head relative to the body (or sideways in some circumstances) - I don't think you can get them from forward head movement (could be wrong though - standing by to be corrected). I have never heard of whiplash injuries being an issue during ejection, ergo there must be no need for such a system.
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And if we all switch to ucav's we can all sit in a La'z'Boy (or whatever floats your boat) and fly with a beer in hand. There would be no need for a master race as the engineers could fly it, it can't be any harder than fixing it.............
