It happened March 28, 2003, and only now, with the pressure on Tony Blair to step down as high as it’s ever been, is it being leaked. Quite the coincidence. The Sun doesn’t say where they got it, but it does quote a “senior U.S. military source” as saying, “This tape needs to get out. The pilots need to be brought to account.”

Six errors, according to the paper:

Circling at an altitude of 12,000ft, the A-10s spotted Iraqi vehicles 800 yards north, and the British patrol less than three miles west. ERROR ONE came when they asked the Forward Air Controller, call sign Manila Hotel, if friendly forces were around the Iraqi vehicles — not to the west. In ERROR TWO neither pilot gave the precise grid references for the Household Cavalry patrol to double check its identity.

ERROR THREE saw them convince themselves the identification panels were really orange rocket launchers.

In ERROR FOUR POPOV36 decides to attack, saying he is “rolling in” — without permission from the Forward Air Controller. POPOV35 asks for artillery to fire a marker round into the target area to clear up confusion.

But ERROR FIVE came when POPOV36 attacked without waiting for it. In ERROR SIX POPOV36 strafes the column for a second time but still doubts its identity.

It’s long but gripping, and of course devastating when the word comes about error. They actually tell the pilots while they’re in the air that there’s been a man killed. The action begins at around 5:15, but the drama starts a few minutes later at 7:30 when the dispatcher informs them that they’ve got friendlies in the area — moments after they’ve made a second run on the convoy.