Original U.S. Vietnam War Era Named APH-5 Helicopter Pilot Flying Helmet by Sierra Engineering Company With Early “Bowling Ball” Storage Bag - Size Large Category_Martini-Henry Parts One observer

One observer

Most technical manuals will tell you what type and model of test equipment was used to prepare the voltage charts

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Seventy seven men were executed on charges of treason though historians tend to think the figure is higher

Approximately 800

Original U.S. Vietnam War Era Named APH-5 Helicopter Pilot Flying Helmet by Sierra Engineering Company With Early “Bowling Ball” Storage Bag - Size Large Category_Martini-Henry Parts One observerOriginal Item: Only One Available. This is a solid example of a Vietnam War APH 5 Flying Helmet, as used by all branches of service during the Vietnam War. This Helmet appears to have been very well used, and repainted multiple times during its period of service. Has a functional tinted visor as well as boom mic and issued hearing protection. Size is a LARGE and overall condition is very good. There is an original manufacturers label is still present