Is that an Archer near the beginning? https://www.youtube.com/watch?v=THQJA8QWeyk Interesting to see the AA cannon in a ground attack role, some serious firepower pounding that city, I like it
..and don't you just love that brace of "liberated" chickens hanging off back of the Churchill at 1:06 !
Just remember 'Archer' is a postwar term, Wartime one varies but they are frequently documented as Valentine 17 Pdr SP. Goch is very well documented, as always cracking footage.
AA guns were being using in the ground role throughout the campaign from D Day onwards. Bofors guns were used more and more after thew Operations Research teams came to thew conclusion that the morale effect of artillery fire was a function of the number of bangs as well as the weight of HE. As a result fireplans included more and fire from non field artillery - tanks, anti tank guns and Light AA guns, as shown in the film. These were known as "pepper pot barrages."