NOD
“Summary We adhere to the ATC speed request - we have tea and biscuits with our Mgmt. We adhere to our Mgmt/SOP speed schedule, you get tea and biscuits with your Mgmt. Result - Mgmt is the common factor - quelle surprise”
Or the third option, you adhere to your Mgmt/SOP speed schedule and a lighter aircraft behind you (at the minimum vortex spacing) has a nasty because you slowed down early without advising ATC. We all get to meet our respective Mgmts, but only the ATCO gets tea and biscuits, and (quite possibly) continued employment!
Why? Because the pilot failed to comply with an ATC instruction, and he/she didn’t tell ATC that they would be unable to comply with it. Simply speaking this is against the law.
All ATCOs (and certainly those at the London airports) are aware that certain aircraft and certain weather conditions mean that aircraft are unable to comply with ATC speed instructions and we don’t have a problem with this. We also know that you will fly your aeroplanes to comply with your company SOPs and we don’t have a problem with this either.
The vast, vast majority of the time slowing early to meet your SOPs has no effect on operations (apart from maybe the odd go-around) and we all go home to live another day. The vast, vast minority of the time (occasions we’d be unlucky to see in our careers but which are still quite possible) an incident / accident caused by the above circumstances would lead to the pilot being legally responsible.
The ideal answer should be (having advised ATC that you can’t meet a speed restriction), to advise your OPS department every time this happens. If this happens frequently (and I imagine it does!), your OPS should then liaise with our OPS and procedures (either yours or ours) will change for the better.
Just make sure it’s the OPS department of the relevant ATC unit they speak to and not senior management, who quite frankly couldn’t organise a pissup in a brewery, let alone an ATC operation in an ATC centre!