My dad was a hydraulics & pheumatics tech in the USAF Reserves. The Airlift Group to which he was attached has a B-25 that the commander used as his personal liason craft. They were tasked to work on the nose gear. Well SOMEBODY re-connected the hydraulic lines backwards. That spring day at Willow Grove NAS they did a taxi test. The pilot cut the nose wheel gear to steer onto the main strip and the plane went the opposite direction, off the taxiway sinking the nose gear into the mud about halfway up the strut. The colonel was not a happy man.
Every repair I do ( industrial maintenance everything from pneumatics to PLCs) I always verify the repair. It sounds like a practical joke.
Probably pretty easy to do in those days but I'm surprised they didn't jack it up and test it before the taxi test.