The US Military upgraded their CH/MH-47F's with the CAAS (Common Avionics Architecture System) which would i believe open up their capability to be compatible with all future avionics fits no matter what was fitted in the flight deck. (I stand corrected if wrong).
Surely Boeing construct their new airframes with this CAAS installed so all future buyers including that outside the USA could fit anything they wanted into the flightdeck without any problems with it not fitting or installing properly.
So why have the British had such a problem with the avionics fit of the Chinook HC3, or did Boeing only produce this CAAS to fit US Avionics only creating a problem to buyers outside of the USA?
It is now going to take a a year or two for the HC3 to be downgraded into an HC2 fit just so we can get it into theatre...
If we had not farted around with the avionics in the first place they would have been flying years ago as PCD stated with pretty much all avionics.