Gerry didn't know how the bomb worked. He'd heard some of the egghead technobabble, but all he needed to know was where to drop it from his plane. He checked his altimeter, speed and bearing again. Still on course. He cast a nervous look back towards the bomb in the hold. The thing gave him the creeps, to be honest. They'd called it a "Heisenbomb" or something. It was supposed to erase part of reality by collapsing a quantum something into a singular whatsit. Might as well have called it a voodoo bomb for all the sense it made to Gerry.
He saw the city lights spread out below him - Rocvale. The whole city was the target, but the bomb needed to be dropped in the centre. The radars hadn't spotted him, and probably wouldn't, and he'd be gone before they could do anything about it anyway. His plane was the latest and greatest in stealth and speed.
Flying over the centre of the city, Gerry's finger hovered for a second over the bomb release switch. He felt like, maybe, he couldn't do this. Then some other part of his brain stepped up and said "Don't worry, I got this", and his finger flipped the switch.
The bomb tumbled for a second or two before its fins stabilised its downwards course. It began to make a high-pitched whistling tone as its speed increased. People in the streets heard the bomb approaching, pointed and shouted, ran for cover. Some cursed their government for starting this awful war before running to their shelters and shutting the doors.
Gerry watched the bomb fall, but when it hit, there was no flash of light, no thunderclap, no mushroom cloud, no crater in the ground. Rocvale just stopped being there. There was a green field where there used to be ... something ...
Gerry shook his head to clear it. What was he doing again? He automatically checked his altimeter, speed and bearing, then his flight plan. He was ... on a test flight for the new stealth plane? Yes, that was it. He turned the prescribed circle and headed back to base. On the radio, the control tower seemed to have had a similar memory lapse about the same time as Gerry. Weird coincidence.
Gerry kept feeling somewhere in the back of his mind that there was something he'd forgotten. Not something he hadn't done, but something he had done, then forgotten about, but he could never quite put his finger on it.
Mokalus of Borg
PS - How would you know if this had ever happened?
PPS - It might leave behind some weird conspiracy theories, at best.