The interphone would work just fine and Cooper used it..he would of told them everything was fine on the "radio" vs the interphone..
perhaps R99 can explain the need for a radio...I'm only a sim pilot lol
interphone is stationary,, a radio is mobile as he moves in the plane/airstairs..
but it may have been a ploy to get a radio,,
we need more info on that radio.. for who and what type and if Cooper took it.. or not
I can't even guess why the crew needed a radio that Cooper knew about.
CONSOLAN - was a long-range navigation aid that is received via a simple radio.
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