1944...The first attack was conducted on 30 July, on a derelict Japanese freighter, the YAMAZAKI MARU, that had grounded itself near Cape Esperance on Guadalcanal Island in the Solomons. Six TDR-1s, with four intended for the attack and two as backups, were committed to the mission, all armed with 900 kilogram (2,000 pound) bombs. Two cracked up on takeoff, two performed attacks that were frustrated by dud bombs, but two went off with very impressive bangs. It made for great film footage, but by that time the effort's standing was so low that Smith had to lobby very hard just to keep the program from being immediately cancelled.
Beginning on 27 September 1944, STAG-1 conducted a series of attacks on Japanese installations on the island of Bougainville. When the attacks ended on 26 October 1944, STAG-1 had expended 46 TDR-1s in combat, with 37 performing attacks and at least 21 hitting their target. The Japanese found the attacks startling, believing that the Americans had taken up suicide attacks.
The end score seemed encouraging, but it wasn't enough to stave off cancellation. The TBM-1Cs were dumped into the ocean to dispose of them and the personnel reassigned to other duties. It was a bitter pill to swallow for the program's officers and men, but by that time the war was clearly going to be won by other weapons and the TDR-1 was no longer seen as particularly relevant. Apparently some further work was done a "TDR-3" that featured radial engines, but though a picture of such a machine survives, it may have been a mockup, and it's unclear if it ever actually flew.
Tokyo Rose herself commented on the strikes, labeling the drones “American Kamikazes.” The Japanese failed to realize the planes had no pilots!