firewired

Sorry, to be obtuse, but why does everyone feel that having your head in contact with the head restraints is dangerous? It seems to me by minimizing distance of the gap to no gap at all, the potential travel of your head in an impact decreases the potential secondary hyper-extension injury that follows the initial hyper-flexion during impact. In my mind this would allow the head restraint to do what they were designed to do and absorb the energy of the impact.

Volvo head restrains are very well rated, and jut forward to contact the head.

Wiu-Bimmer

Sorry, to be obtuse, but why does everyone feel that having your head in contact with the head restraints is dangerous? It seems to me by minimizing distance of the gap to no gap at all, the potential travel of your head in an impact decreases the potential secondary hyper-extension injury that follows the initial hyper-flexion during impact. In my mind this would allow the head restraint to do what they were designed to do and absorb the energy of the impact.

Volvo head restrains are very well rated, and jut forward to contact the head.
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wow!!! could not agree with you more!!!
And yes, I would like to be able to rest my head on the head rest (Or restrain, whatever) I would just like to be able from time to time.

sg530

I have tried to learn as much as possible about active head restraints as I too thought the position of the restraint was too far back.
BMW says it is not intended to be a head rest during driving. I have the comfort seats with the active restraints and they have bendable face on the front I assume to add some level of comfort. The adjustment doesn't allow contact in normal driving position so it appears useless to have the feature. I know the head is not supposed to touch the restraint during driving and that in a rear-end collision, the restraint will jump forward to intercept the head before it is hyperextended. This is by design. I would realy like to hear from a bmw rep the exact intent of the different head restraint designs. Standard and sport seats must be treated differently AFAIK.
Other active restraints, like on Nissan, is mechanical and also catches the head as it is bent back in a rearend collision. There is no discussion about the head-to-restraint distance nor the comfort level of any of these active restaint designs designs anywhere on the web.
If I wish, I can lean back and place my head in the restraint cushion, but this is not good for driving, but ok while resting and stationary. The bendable face cushion is cute but not very functional if you ask me. I would rather it be puffier and bigger so it still can protect but also provide support for the head is desired. It may look odd and asymetrical, but maybe the passenger head restraint could be made more comfortable?

firewired

To me I wasn't talking as much about the bendable portion of the restraints. I think that is simply for comfort. I am talking about the fact that I don't think having a gap between your head and the headrest makes it any safer, I conversely think that that having your head in contact with the pad is probably safer being that there is less potential distance to be traveled by the head in an impact.

Rudy

firewired, I think you're correct that a head touching the restraint would be safer in an impact.

I think the reason you're not supposed to drive that way is that resting your head on the restraint can lead to driver fatigue or worse, if a fatigued driver rests his head on a restraint, he may fall asleep.

Also, resting your head on the restraint can reduce your reaction time if you need to quickly move your head to see a situation because your neck muscles are more relaxed, etc.

sg530

With the active head restraints, one should not rest the head onto the cushion while driving. This is according to BMW. You may injured by the moving head restraint if your head is too close.

firewired

Where does BMW say that? I was unable to find any statement similar to that in the owner's manual. The only thing the manual says about the reactive restrains is: to not put covers on them, don't hang things from them, and to essentially have them positioned properly.

I would think if BMW thought it was specifically unsafe they would specifically warn about that. They warn you about 100 other things, most of which seem like common sense.

I don't think that the restraints move forward to counteract a potential space, though they may partially accomplish that as well. I think the forward movement is meant to not close a space but to counteract the inertia of your head traveling rearward and hyper-extending your neck. Both SAAB and Volvo have similar designs in head restraints and both were highly rated. The restraint moves forward on pivots not explosive charges like some seat-belt pre-tensioners and airbags.

Like I mentioned previously I for one think the whole premise that having your head unsupported is more likely to cause injury than by having it supported by the seat head restraint. One would think if it were unsafe, BMW would have a specific distance recommended like they do for airbags.

sg530

Sorry you you don't believe me, firewired, even after I already said I researched the issue months ago. <_< The 'active' in the bmw restraints in the comfort seats is an explosive gas discharge like an airbag. These restraints are designed to be several inches away from the head during driving and catches the head to prevent hyperextension during a rear-end collision of sufficient magnitude to trigger the restraint. The system is described or was described on one of the many bmw websites. The manual doesn't explain much of anything. There is a lot of other litterature out there to read besides the manual. The non-active restraints IMO could touch the head during driving but I believe BMW doesn't recommnd this. This is also what I was told when at the Performance Center.

firewired

Can you link or post one of the sources which you mention?

sg530

Link tells a little about restraints but not so much BMW, however, mentions restraint shouldn't touch head.

http://msnbc.msn.com/id/6470994/

Pyrotechnic operation mentioned here:

http://www.autoweb.com.au/cms/A_55591/newsarticle.html

Just the first ones I found today to answer the question.