Becker asked:
What is the relation between the minimum SID climb gradient, usualy 3,3%, and the standart 2,4% and 1,2% of the initial climb the limit our take off weight?
Old Smokey replied:
The 2 sets of rules have virtually nothing in common, especially in terms of vertical and lateral clearance of obstacles.
Thats about it really.
Consider this:
Most of the time SIDS are flown by transport category aircraft. But SIDS are not exclusive to transport category ops. SIDS are available to all IFR operations. ATC could issue a SID to an IFR Cessna 182, or the IFR rated PPL could elect to do a SID when departing from an AD OCTA.
SID is IFR, not Performance.
If the standard 3.3% SID gradient relates to
anything it is more likely to relate to a general IFR requirement -- haven't had the time to check it, but a 2.5% gradient requirement for IFR obstacle clearance in missed approach plus 0.8% factor rings a bell.........