HMD & Neck Injuries:---

[Arsalan]

Exactly my point. Without knowing the weights and the change caused by the HMD, one cannot say anything. Mitigation measures would depend on the numbers.

Yes. As i mentioned, the change in terms of grams is not that much so that number wont make everyone realize what harm it can do. However when you talk in terms of percentage weight increase, which is around 30% than it becomes a problem.

 

[VCheng]

Yes. As i mentioned, the change in terms of grams is not that much so that number wont make everyone realize what harm it can do. However when you talk in terms of percentage weight increase, which is around 30% than it becomes a problem.

It is not just the weight, but its distribution and orientation relative to the ejection axis, and a host of other factors. The benefits of HMDs have to be weighed against the risks it may pose during ejection and the technology is still evolving.

 

[Arsalan]

It is not just the weight, but its distribution and orientation relative to the ejection axis, and a host of other factors. The benefits of HMDs have to be weighed against the risks it may pose during ejection and the technology is still evolving.

Yeah all other things plus quite a few more are important but the problem here is the weight actually. As a mentioned, a recent study concluded a weight reduction to sort out the problem. It can come in form of reduced weight of HMD or that of the helmet. Will be a costly exercise! The pilot helmet is no joke really, a lot of study goes into that simple looking piece of equipment.

 

[VCheng]

Yeah all other things plus quite a few more are important but the problem here is the weight actually. As a mentioned, a recent study concluded a weight reduction to sort out the problem. It can come in form of reduced weight of HMD or that of the helmet. Will be a costly exercise! The pilot helmet is no joke really, a lot of study goes into that simple looking piece of equipment.

It is a complex subsystem to be sure. At some point, neck stabilization and support devices will need to be incorporated to prevent serious injuries at ejection.

 

[Arsalan]

It is a complex subsystem to be sure. At some point, neck stabilization and support devices will need to be incorporated to prevent serious injuries at ejection.

The way aviation is progressing, specially fighter aircraft, i wont be surprised to see pilots suited in space suit like thing. They will want to put more and more control in direct contact with pilot and that may increase the weight of subsystems that the pilot will be "wearing", requiring specially modified suit.

 

[VCheng]

The way aviation is progressing, specially fighter aircraft, i wont be surprised to see pilots suited in space suit like thing. They will want to put more and more control in direct contact with pilot and that may increase the weight of subsystems that the pilot will be "wearing", requiring specially modified suit.

If further progress does not make the pilot's physical presence inside the actual aircraft obsolete, then yes.

 

[Arsalan]

If further progress does not make the pilot's physical presence inside the actual aircraft obsolete, then yes.

It wont, in my opinion it may become optional but there human direct involvement will be there for most part. (no fan of sci-fi)

 

[VCheng]

It wont, in my opinion it may become optional but there human direct involvement will be there for most part. (no fan of sci-fi)

Now that is a whole 'nother discussion.

 

[Armchair]

Something like this, combined with cuing of WVR AAMs could perhaps create a simple HMD/S :

 

[MastanKhan]

It is not just the weight, but its distribution and orientation relative to the ejection axis, and a host of other factors. The benefits of HMDs have to be weighed against the risks it may pose during ejection and the technology is still evolving.

Hi,

Seemingly there is no benefit of HMD over a BROKEN NECK---. No one will say let me have a broken neck for 1 or 2 enemy aircraft---.

The criteria would be---are you physically capable to handle the whip lash force or not---.

A minimum weight is mentioned---what is not mentioned is extra strengthening of neck muscles---like football players to compensate for light weight pilots---.

It would be interesting to find out if a stronger physique thru physical fitness may reduce neck injuries due to heavier weight---.

 

[VCheng]

Hi,

Seemingly there is no benefit of HMD over a BROKEN NECK---. No one will say let me have a broken neck for 1 or 2 enemy aircraft---.

The criteria would be---are you physically capable to handle the whip lash force or not---.

A minimum weight is mentioned---what is not mentioned is extra strengthening of neck muscles---like football players to compensate for light weight pilots---.

It would be interesting to find out if a stronger physique thru physical fitness may reduce neck injuries due to heavier weight---.

A work in progress, as me and @Arsalan mentioned above.

 

[GriffinsRule]

Another obvious point not mentioned is, apart from the percentage increase in weight, the 500grams of additional weight will increase many times over under the effects of Gs

 

[SQ8]

The JHCMS has been put through physiology tests and while the extra weight associated with it and other HMD systems of similar nature( The Scorpion is basically an eyepatch that adds much less weight) does increase the neck strain, it also goes in terms of a lighter helmet material in the most recent HGU iteration.

Weight balance is also a consideration along with the most key factor of pilot physique. USAF now has dedicated physiotherapists at its key A2A fighter bases who help relieve muscle tension after each sortie.

 

[messiach]

@Oscar @VCheng @Arsalan @MastanKhan Spinalcord injury is not related to weight but to torsional forces damaging fixed neck at ejection. The major weight concern is because of CAAHP module. Future systems would be distributable gaining considerable weight reduction.

 

[VCheng]

@Oscar @VCheng @Arsalan @MastanKhan Spinalcord injury is not related to weight but to torsional forces damaging fixed neck at ejection. The major weight concern is because of CAAHP module. Future systems would be distributable gaining considerable weight reduction.

Yes, that is why I referred to the the weight, and its distribution relative to the ejection axis. Weight reduction is a workable solution, up to a limit. Future designs will need to look at incorporating a specific neck stabilization device as part of the ejection sequence to limit not only these torsional forces, but also the compressive forces, in addition to distributing the weight of the hardware to other areas, as you mention.