dropped from Trojan. Models Churchill III and IV AVRE Churchill AVRE was a Churchill III or IV armed with a 230 mm petard spigot mortar, officially designated; Mortar, Recoiling, Spigot, 29mm, Mk I or II. The mount replaced the 6-pounder gun in welded turrets on the Mark III and cast turrets on the Mark IV, otherwise the vehicles are identical. The 6-pounder gun mounting was modified, and retained the 6-pounder sights although "flying dustbin" effective range was only around 80 yards of 230 maximum. Crew was increased to six to accommodate a demolition NCO in addition to driver, commander, gunner, wireless operator, and co-driver/machine gunner. Internal ammunition stowage and the co-driver / hull gunner's seat was removed to provide compartments for demolition charges. This housed stores of the "General Wade" 26 lb explosive charge, and "Beehive" charges of up to 75 lbs of explosive. Both types of charge had to be set manually, but could be detonated from the relative safety of the AVRE interior. In the remaining space, compartments in the sponsons were created fore and aft of the side hatches for "flying dustbin" ammunition. Churchill VII AVRE Post-war, new Churchill AVREs were created using the Churchill VII base vehicle re-armed with a short barrelled L9A1 165 mm demolition gun. This fired a 64 lb (29 kg) HESH round. Centurion Mk 5 AVRE "AVRE 165" FV4003 Centurion Mk 5 AVRE. Armed with a short barrelled L9A1 165 mm demolition gun, it entered service in 1963, replacing the Churchill AVRE. The vehicle was later renamed AVRE 165 relating to its primary armament. The armament was capable of firing a 60 lb (29 kg) high-explosive squash head (HESH) round. The vehicle front added a dozer blade to the front, and frequently towed the Giant Viper for mine clearance or other trailers for stores. Large turret bins provided stowage. The dozer attachment was also provided on regular tanks as the FV4019 Centurion Mk 5 Bulldozer. Centurion AVREs remained in use, and were up-armoured for Operation Desert Storm in 1991. Centurion Mk 12 AVRE "AVRE 105" FV4203 Centurion Mk 12 AVRE. A modified Artillery Observation Post vehicle, it was armed with the conventional 105 mm Royal Ordnance L7 rifled gun and provided with track width mine clearance ploughs instead of the dozer blade on the Mk 5. Chieftain AEV and FV4203 Chieftain AVRE Replacement of Centurion AVRE was planned to be accomplished by