Over a billion pounds were wasted on this two-headed monster - leading to a much reduced budget to buy AWACS - which is what some in the MOD wanted in the first place. However, a Labour Govt was in power, the country was strapped for cash and UK jobs were a major issue. Industry told the MOD what it wanted to hear in 1977, namely, that Nimrod would meet the spec and secondly, it would be in squadron service by 1982. One day, an insider will write the true story of how this outrage came to pass, but here are a few salient details.
One memorable quote from the very early 80s was, "It's all proven technology, all we have to do is to integrate it.."
The airframe featured two radar heads: one at each end of the fuselage, making the test aircraft one of the wierdest-looking things ever to fly. Transmitter cooling was never the problem that crew room banter would have people believe.
Its all up weight that was so out of control that at one point it wasn't going to be possible to fit a jump seat for an IRE to occupy. Meanwhile, the (even by then obsolete) Shackleton trundled on - and on, and on, and on.
It is worth noting that the prime contractor for this abortion was the MoD. The contractors involved were paid cost plus for all the work they did. As they delivered what they were asked to that's not surprising. The fact that the radar (as ordered) was not compatible with the airframe (as ordered) didn't seem to matter to the Civil Servants involved. Hard working no doubt, just incompetent and not fit to run a procurement programme for a cheese roll.
All in all, a total spinning bow tie extravaganza of proportions bordering on biblical. Unsurprisingly, it was all down to decisions undertaken during the tenure of... wait for it... a Labour government. Good eh?
It's all here: Nimrod AEW3
Lessons learned = 0
As proven by the Nimrod MRA4 program some decades later.