Following on from my last post.
In the early eighties we pulled S76As back from America and they went into the UK HQ hangar to be fitted out IAW the CAA Regs. When I picked them up from the docks in Antwerp, Le Harve and Southampton they had DME and another thing called Omega. I flew them to the UK and after my company engineering had finished I went down to do their UKCAA C of A.
The DME had been pulled, together with the Omega and had been replaced with Decca Tans. I could understand why Decca Tans was in, it was a company standard, but I could not understand why the DME, which was free, had been pulled. I was told that it had been taken out so that the aircraft's fit was the same as every other company S76 in the UK.
Three months later the Norwegian CAA stipulated the Decca ranges were unacceptable for range chacks in Norwegian airspace, As Norway was high on the IFR diversion list there was a frantic two weeks whilst they refitted all the DMEs thay had taken out.