Flight gear is designed for two purposes:
for use or protection while in flight
for use, protection or signaling while in some post flight environment
Flight suits are the most fundamental piece of flight gear. In the pre0Vietnam years, cotton international orange flight suits were issued by the Navy. The color was for recognition. The cotton was treated with a solution to presumable provide some protection against fire. General understanding was that it was not very effective and in any case its utility faded after a few washings. Fireproof green nomex flight suits were year away when we went on the line in 1967, so an alternative was neeed. The most popular option was Marine fatigues (blouse and pants). Still not fireproof, but at least would not stand out like a sore thumb if you were on the ground.
Steel- toed leather flight boots are an obvious item. One modification for combat was replacing the soles with no slip Vibram one, the better to outrun the NvA!
The Integrated harness with life preserver and survival vest was the next item to don. Hip and shoulder connectors to the aircraft harness were built in. Then survival vest contained two pockets: survival and medical.
Some items in the survival kit:
signal mirror to reflect sunlight. It was aimed by looking though a semi-tranparent circle in the ceter of the mirror. The device is surprisingly effective, especially at sea.
Wire saw for building an abode in the wilderness, I suppose
Fishing gear (line, hooks, lures)
High energy candy (Charms as I remember)
The medical kit contained items such as: Adhesive plaster, matches, gauze compress, bouillon cubes, adhesive bandages, soaped tissues, water purification tablets, tincture, petrolatum, hacksaw blade, razor blade and sun burn lipstick.
Some items needed to be accessed quickly, perhaps while dangling in a parachute. These were attached to the exterior of the survival vest or to the torso harness itself:
Shroud cutter for freeing one's self from parachute lines was placed in a handy position on the front of the vest. It had a shroud cutter at one end and a spring loaded kife blade at the other
Pencil flare for signaling, also placed for handy
K-bar knife.
Survival radios. Common to carry two since this the only way you were going to be rescued if downed in hostile terrritory.
Pistol or revolver. Standard Navy issue was a Smith and Wesson 38 Caliber Special revolver. I carried my on a web gear belt.
All flights were conducted while breathing oxygen; the oxygen mask was attached on the left side of the harness over the left shoulder, handy to the oxygen connection.
Exiting aircraft following a combat mission. Note marine fatigues (sleves rolled down over land!) Outline of water bottle in pocket in g-suit, K-bar knife. Gloves were nomex, the only fireproof item we had at that point.
Knife/ shroud cutter