On May 21st, 1944, in the evening, 510 plane Lancaster had unstuck several aerodromes of Great Britain to go to bombard the industrial park of Duisburg, in the Ruhr. The German anti-aircraft defense machine-gunned the British bombers and several people were shot and had to turn back, not having possilblity to release their bombs.
Among others, the DV 309 of the 550th squadron based to North Killingholme was intercepted by a German night fighter based in Sint-Truiden. The plane, was quite hard touched while it overflew the region of Westerlo. She crashed on the hamlet of Schobbroek, causing an immense explosion done by the load of bombs which she had still on board. The damages were considerable, nothing more remained standing, and several farms situated nearby were completely destroyed. Luckily, no inhabitant was involved in the crash, they had all gone to a party, this evening.
On the other hand, the whole crew died immediately and the bodies of three of them did not been find, so much the explosion had been strong.
On the 510 engines had committed in this mission, this night, 31 never returned to their base. Three of them belonged to the 550th: the DV 309, LL 851 which was shot down to Heimolen, near St-Nicolas and the LM 319 which was probably shot down above Germany
Source: http://www.rebecq-memorial.eu/westerlo.php