Hi Dave
Yes the car parts
Al cars from 1-999 had this bit and from 1001 to date have this.......and I have number 1000. :curse:
As to the 539 I always wondered about the different designation but that could have just been a later built with mods. These were some of the last or perhaps in Britiain the last 500 where as the 510 were the first.
Visually they were built with hush kits and that set them apart for a while until the others had to be modified. Also they had the forward airstairs.
As you say the Trident necessity was fading..the 510 were with the Super One-Eleven division which was Manchester based so were in league with Tridents and these three 539 were BHX based on what had been the Channel Islands division.
I only ever saw them on those routes and they did seem to run separate from the main fleet.
Looking as they did as being a fleet within a fleet I have always wondered it they were more like normal One-Elevens rather than the BA hybrids which was in fact a BEA thing so really goes back to a different set up entirely.
Although there is every reason to assume they were the same, just about every thing about their use was different to the point where it could also be assumed that they were standard One-Elevens. :think:
BA didn't really need them but had to buy a 1-11 for every 10 Boeing 737's ordered....so in a way they were never even wanted. :sad:
That could have meant a straight cheaper off the shelf One-Eleven and then operate them away from the main fleet.
Garry