As for dealing with the Bocage country in Normandy, the Cullen Hedgerow device was not the only key locally-devised innovation. The problem was that the infantry needed to talk to the tanks directly. In a typical hedgerow assault operation the tank would break through the wall and the infantry would spot the areas that needed some heavy fire and relay that info to the tanks, very much in real time, like a fighter pilot would tell his wingman about a target.

US tanks were equipped by that time with what we would call low band VHF radios. These were vastly superior to the HF sets that were used earlier in the war, offering easier, channelized operation (literally like the push button radios we have in cars) offering much more bandwidth and more frequencies, and being almost immune to interference. And according to at least one report offering the unexpected side benefit of interfering with German communications in that same band.

But the radios in the tanks pretty much could not talk to the infantry. The tank radios were heavy monsters, virtually bulletproof but totally unsuitable for portable operation. The handheld walkie talkies used by the infantry were in a totally different band. The backpack radios had only limited frequency overlap with the tank radios. The other portable sets in the right band were designed to be put down and set up, not hauled on the run under fire.

The answer was simple. They attached a phone box on the back of each tank and the infantry, hiding behind the cover of the tank, would pick up the phone and tell the tankers over the intercom what areas needed attention.

Note that this was directly opposite to the philosophy in the Philippines in 1941, in which the local command got in a spat with the Ordnance Dept and so the Stuart tanks were equipped with no radios at all. “Nothing concentrates the mind so much as the prospect of being hanged on the morrow.”

Starling:
My best suggestion is to look for the Columbia mishap report on the Internet. It is freely available. But be aware that there is “the rest of the story.” I have a LOT of other material available outside the formal report, and if I can get it in a format that I can send you I will.