When you are given the OLY1B SID you are always given a 'maintain 5000'. as Over & Out said, it is due to the interaction with Heathrow departures.
Not long after the SID came in, a RYR B737-200 flew the SID and climbed to 6000 as per the instructions. Unfortunately a slow climbing Virgin B747-200 (shows how long ago this was!) was still struggling through 6000'.
The stepped climb warnings are on all the BPK SIDs off runway 26, and normally the CPT SID of runway 08. At the moment this has a 4000' restriction on it because the new SID conflicted with the London City northbounds. This will return to a stepped climb warning in September when another new CPT SID comes in.
The warnings are due to the number of level busts over the years.
Hope this helps.
Last edited by Level bust; 13th Jul 2010 at 08:34.
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