I have brought my 21 T Model Ford into the jet age by fitting those fancy Dan, new-fangled airplane shocks all round Sent from my moto g(6) play using The H.A.M.B. mobile app
I may be mistaken about this specific installation, but I doubt the OP is saying these shocks are in fact from/for an airplane. The common tubular shocks that have been used for decades on autos and trucks were a design adopted from shocks first appearing on aircraft. At the time, the typical automotive shock absorbers were lever action, like the Houdaille and Delco-Lovejoy, either as separate units or incorporated into the upper control arms. Introduction of tubular shocks were advertised as ‘airplane shock absorbers’ to capitalize on the public perception of the advanced engineering of aircraft. For awhile thereafter, tubular shocks were often referred to as ‘aircraft type’ shocks to distinguish the style from the (at the time) more common lever style.
Sorry - missed this one... As Hnstray says, it's a reference to the fact that tubular dampers were often referred to as airplane shocks and were the hot ticket back in the days of lever arm shocks - although given the number of aircraft factories and scrap yards in So Cal som hot rodders may well may well have used aviation parts. I do know of a London Underground engineer who used the dampers from the tube train doors on his T bucket. The brackets were fabricated at both ends.
I believe that this is correct ^^^^^ I vaguely remember someone calling them airplane shocks when I was really little. By the time I was old enough to play cars and motorcycles on my own we were calling them tube shocks, not to be confused with tube socks.