Hi Bookworm,
Thanks for taking the time to look this up.
This statement
"Also if I don't hear a reference to stepped climb this is an indirect reference to the cancellation of the 15BNN 6,000' requirement. "
Was only mentioned in my initial post ....came from my local F/O ...sounds like an urban myth.
The SID initial altitude report would catch someone about to climb directly to 6,000' feet but would not stop the potential 5,000' level off followed by a later alt bust as they climb to 6,000',
I think you hit the nail on the head though when you said
"An explicit clearance to a higher level cancels any intermediate levels in the UK "
What I am trying to suggest is that "not above altitude 5,000'" is an explicit cancellation of the SID vertical profile beyond 5,000'.....it leaves no room for interpretation
If ATC tell me to maintain altitude 5,000' in the air this would be an explicit cancellation.
But am I really not convincing anyone that saying "maintain altitude 5,000" as part of the departure clearance (on a SID which requires you to do this for six miles anyway) is not as explicit. In a similar way to when we report the initial SID climb level on first contact....we are only saying that is where we will first maintain level flight....not that this is where we intend to stay.
Don't get me wrong..if ever I fly into Luton again I have bought the intention...but unless someone can dig up the phraseology section which says this (maintain altitude 5,000')is the correct way to cancel a stepped climb at the departure clearance phase (and I am therefore the only one on the planet who does not know this) then "if it can go wrong it will go wrong" may rear its ugly head in the future.