jahall4
Well-Known Member
- Joined
- Jul 21, 2014
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Im surprised I have not found more about this on the forums. Maybe a post or two, so if Im overlooking something that answers my question directly please point me on the right direction.
Seems that there is some consensus to place the pins as far back on the shoulder as possible, reason being that if the pin fails to shear the less time it spends dragging against the shoulder and the nose would still come out.
Im dubious of that conclusion because in order for that to happen the pin would have to come out of the hole in the nose cone shoulder and deform the body tube and/or nose cone shoulder. My instinct is that would take more force than the ejection charge is capable of overcoming. And, even if the cone exited the chute it could get caught on those same bent shear pins.
It would seem to me that it is more likely that the aft position of the shear pin holes could actually end up venting ejection gasses before the shoulder has exited the tube. If the pressure is marginal for whatever reason it could mean a failure of the main to eject.
Seems that there is some consensus to place the pins as far back on the shoulder as possible, reason being that if the pin fails to shear the less time it spends dragging against the shoulder and the nose would still come out.
Im dubious of that conclusion because in order for that to happen the pin would have to come out of the hole in the nose cone shoulder and deform the body tube and/or nose cone shoulder. My instinct is that would take more force than the ejection charge is capable of overcoming. And, even if the cone exited the chute it could get caught on those same bent shear pins.
It would seem to me that it is more likely that the aft position of the shear pin holes could actually end up venting ejection gasses before the shoulder has exited the tube. If the pressure is marginal for whatever reason it could mean a failure of the main to eject.