If the US Navy needs more fuel capacity...

The Navy and Martin felt that a new version, the P6M-2 would provide a useful aircraft. The first was rolled out in early 1959. Changes included new, more powerful J75 engines, an inflight refuelling probe, improved avionics and a canopy with better visibility. A buddy refuelling drogue kit had also been developed to fit in the bomb bay. Three had been built by summer 1959 and Navy crews were moving them through operational conversion when the program was abruptly cancelled in August of that year.