Salute!
Interesting....
Back in the day, "Knife" was the callsign of USAF special ops helos that carried troops to strange and dangerous places in SEA. When they flew CSAR, they were called "Jolly". When I flew escort for the Knives, I was called 'Hobo". On the CSAR, I was a "Sandy". Guess they have kept the traditional callsigns.
Knives flew the last combat missions of the whole steenkeeng war at Koh Tang Island off the coast of Cambodia in 1975. Lost several plus a buncha USMC folks See:
https://en.wikipedia.org/wiki/Koh_Tang
My squadron covered the debacle, but the all-knowing folks at 7th/13th AF HQ knew better and did not assign us the helo escort mission that we had practiced and flown with the same helos many times. So we held overhead as the first two helos were slaughtered. We were supposed to be CAS, but there was no FAC there. A grand CF, if you ask me. We were the only dedicated helo escort attack unti in the theater and not assigned to get the Knives in for the troop insertion. That part of the story is not told or documented.
My roomie was the one that fired the rocket that stopped the boat, and my senior wingman sank a patrol boat with a 2.75 in rocket!
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The V-22 sounds like a multiple helo formation, if you have one fly close to you. After a bit, you can tell the difference from a coupla Apache or Blackhawk helos. Their twin tail is also a giveaway with a visual, duhhhh..
Gums sends...