[rtkwe]

> In 1941, the first "Victory Vertical" was dropped by parachute, complete with tuning equipment and instructions.

Above is from the posted article, in a less fluffy piece [0] someone else posted in these comments their transport crates included: "a set of tuning tools, instructions, spare parts, and sheet music consisting of light classics, Protestant hymns, sing-along tunes, and boogie-woogie numbers"

Basically they didn't try, they provided the tools to tune and repair them and counted on the fact that there'd be a number of mechanically minded people where ever these went (for repairing more normal army equipment) that could do a passable job of keeping them working.

Heck, with a drafted army there's a decent chance on bigger bases for there to be someone who's actually who's worked on piano's in some capacity before.

[0] https://www.steinway.com/news/features/victory-verticals