She was lost on 7 November 1944, after hitting a mine in heavy seas off Ostend, Belgium, sinking with great loss of life, particularly amongst her Royal Air Force passengers.
This presented the 2nd Tactical Air Force with an opportunity to conduct necessary servicing, repairs and overhaul of radar installations in North West Europe as “partial downtime” was unavoidable in the process and the defences could not be "down" when the Luftwaffe was active.
[citation needed] All such major maintenance after the D-Day landings on 6 June 1944, until November 1944, had been accomplished by small “Mobile Signals Servicing Units” (MSSU) which had been enormously successful.
1 Base Signals and Radar Unit” (BSRU), which had completed eighteen months training at the Signals Battle Training School, to land in France once the Normandy bridgehead was sufficiently stable but due to the MSSU’s success and the greater rate of territorial advance than expected, the BSRU had been held in England until a more suitable time.
By mid-afternoon when they arrived off the Belgian coast conditions were terrible, and as a result they were refused permission to enter port at Ostend due to concerns that an accident in the harbourmouth might cause considerable disruption in the supply line for land forces.
[7] At approximately 15:00, within sight of Ostend the bow section of LST-420 struck a German mine which tore a large hole in the ship's hull causing it to break into two parts.