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Unusual SPH 4 Helmet+Oxygen Mask.
- Thread starter a2 fng
- Start date
dav3469
Active Member
It is an SPH-4. Don't know about the wiring difference's (British vs. U.S.) but I have seen several photos, and accounts of U.S. Army Aviators assigned to aircraft such as
The OV-1 Mohawk utilizing O2 masks with this helmet in their fixed wing aircraft vs. using the APH-5 of that era that is usually seen in fixed wing usage.
I am going to look up the O2 mask in a couple of references I have. Hopefully I can find it. I am not up on O2 masks, but it looks to be of an older vintage than the helmet.
Could it have been put together as just a display? Also, maybe it was obtained surplus by someone who used it in a private aircraft and needed British electronics-hence the change?
Any markings inside the mask? Closest thing I could find in my reference books was a post war A-13A which looks nearly identical with the exception of the dial in the nose area.
The OV-1 Mohawk utilizing O2 masks with this helmet in their fixed wing aircraft vs. using the APH-5 of that era that is usually seen in fixed wing usage.
I am going to look up the O2 mask in a couple of references I have. Hopefully I can find it. I am not up on O2 masks, but it looks to be of an older vintage than the helmet.
Could it have been put together as just a display? Also, maybe it was obtained surplus by someone who used it in a private aircraft and needed British electronics-hence the change?
Any markings inside the mask? Closest thing I could find in my reference books was a post war A-13A which looks nearly identical with the exception of the dial in the nose area.
helodrvr
New Member
It is indeed an SPH-4. But it looks to me as if someone has cobbled together the avionics, especially the microphone. Note in particular the cutting that has been done in the rear of the helmet. An SPH-4 (and the later SPH-5) will have one small diameter hole on the left rear of the helmet (the hole clearly visible just to left of the rather crude, home-made opening with the mike cord.) The connection for the microphone cord comes through this hole, protected from the helmet shell by a rubber grommet. The fitting that comes through this grommet is clamped into place and held firm by two small screws that secure the fitting.
The main communications cord has the wire leading to the connection for the microphone, two earcup wires, and the main cord which connects to the aircraft. Whether using an oxygen mask or a standard boom microphone, this cord is standard with the only options being the choice of length and whether it is straight or coiled. This cord is held in place with a metal strain relief bracket which is anchored in place by the screw shown in the helmet rear view on the far right of the red band. This bracket accepts a piece of the communications cord, a braided portion of the exterior covering, which is knotted into place. This supports the cord and prevents the ear phone wires and microphone wire from being ripped from the helmet if undue stress is placed on the cord.
You know, things that never happen like forgetting to unplug your helmet then exiting the aircraft, or, having remembered to to take your helmet off, dropping it out of the cockpit while it is still plugged in. Unfortunately, I am guilty of both. But I was saved by the strain relief bracket!
The basic design of the avionics package has changed very little in the 40 years since I was issued my first SPH-4. A note here too is that when the SPH-4 first came out, it was only issued to Rotary Wing pilots. As a fixed wing pilot in Viet Nam (U-21- unfortunately not Mohawks,) getting an SPH-4 required a bit of horse trading. I can't remember if I swapped a Swedish-K 9mm or an old Thompson 45 cal for one. But they certainly did not want to issue me one. I was issued one upon returning to the 101st Airborne Division after completing the Rotary Wing Qualification. That said, I have been wearing SPH-4's and SPH-5's ever since. I still do the basic maintenance on the SPH-5's we wear at work. It involves replacing harnesses, suspension, earphones, wiring, and visors. It is all pretty simple as long as the shell is in good health. I don't work on shells. I just put on new parts and pieces.
When I get back to work later this week, I will post photos of a more standard cord installation.
The main communications cord has the wire leading to the connection for the microphone, two earcup wires, and the main cord which connects to the aircraft. Whether using an oxygen mask or a standard boom microphone, this cord is standard with the only options being the choice of length and whether it is straight or coiled. This cord is held in place with a metal strain relief bracket which is anchored in place by the screw shown in the helmet rear view on the far right of the red band. This bracket accepts a piece of the communications cord, a braided portion of the exterior covering, which is knotted into place. This supports the cord and prevents the ear phone wires and microphone wire from being ripped from the helmet if undue stress is placed on the cord.
You know, things that never happen like forgetting to unplug your helmet then exiting the aircraft, or, having remembered to to take your helmet off, dropping it out of the cockpit while it is still plugged in. Unfortunately, I am guilty of both. But I was saved by the strain relief bracket!
The basic design of the avionics package has changed very little in the 40 years since I was issued my first SPH-4. A note here too is that when the SPH-4 first came out, it was only issued to Rotary Wing pilots. As a fixed wing pilot in Viet Nam (U-21- unfortunately not Mohawks,) getting an SPH-4 required a bit of horse trading. I can't remember if I swapped a Swedish-K 9mm or an old Thompson 45 cal for one. But they certainly did not want to issue me one. I was issued one upon returning to the 101st Airborne Division after completing the Rotary Wing Qualification. That said, I have been wearing SPH-4's and SPH-5's ever since. I still do the basic maintenance on the SPH-5's we wear at work. It involves replacing harnesses, suspension, earphones, wiring, and visors. It is all pretty simple as long as the shell is in good health. I don't work on shells. I just put on new parts and pieces.
When I get back to work later this week, I will post photos of a more standard cord installation.
helodrvr
New Member
Here is the rear of my SPH-5. The velcro is for attaching a battery pack for night vision goggles.
The wiring that comes through the rubber grommet is for the microphone connection. The extra wire is for a microphone lip light.
This is a close-up of the main communications cord just below its attachment point inside the left rear of the helmet. The strain relief bracket is hidden by the styrofoam liner.
The retention harness in the newer Gentex SPH-5's don't have the multiple snaps on either side that the older SPH-4 harnesses had. But that style of retention harness can still be ordered.
The wiring that comes through the rubber grommet is for the microphone connection. The extra wire is for a microphone lip light.
This is a close-up of the main communications cord just below its attachment point inside the left rear of the helmet. The strain relief bracket is hidden by the styrofoam liner.
The retention harness in the newer Gentex SPH-5's don't have the multiple snaps on either side that the older SPH-4 harnesses had. But that style of retention harness can still be ordered.
