The following is from AHQ Report 054, Para 157. Note the final part of the paragraph.
157. The organization of 6 and 10 Cdn Armd Regts each into two squadrons of normal Shermans has bee referred to previously (para 103). This arrangement was designed to give close support to each assaulting battalion at the crucial moment of landing. Reserve battalions, jmaking an unopposed landing, would be supported ashore by “normal” squadrons. For a detailed description of the manner in which it was proposed to operate the amphibious tanks, reference should be made to the memorandum, Drill for Launching and Run-in of DDs, issued by 2 Cdn Armd Bde, 13 Apr 44 (W.D., H.Q. 2 Cdn Armd Bde, 20 Apr – 31 May 44: Appx 11). Launching was to take place at 5000 yards from the beach under cover of smoke laid by L.C.G. (L), touchdown being made at H minus 5 minutes. D.D. tanks were thus to form the first wave of the assault, going in five minutes before the leading flight of landing craft hit the beach (See diagram at Appendix “H”). Although it was considered improbable that the operation would be mounted if seas were rough, it was nonetheless entertained as a possibility that the launchng of D.D. tanks might have to be cancelled altogether (Ibid),
6 and 10 Cdn Armd Regts were each in addition to supply two Sherman tansk Vc to be employed as “concrete-busters” in the assault. These would be borne in L.C.T. (C.B.) (see Ships and Craft of Force “J”, Appendix “B”) and would disembark so as to deliver observed fire from their 17-pounder guns against emplacements (R.C.A., 3 Cdn Inf Div O.O. No. 1). Concrete-busters would revert to regimental command on completion of their tasks (2 Cdn Armd Bde O.O. No.1).
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