Hoschi,
There is some good information posted here.
It is the responsibility of the operator to educate crews with the answers to your questions.
JAR-OPS 1.975 and AMC Ops 1.975 state that any airfield with performance limitations should be classified as a Category B aerodrome. I interpret a minimum SID gradient as a performance limitation. In actual fact most of the SID gradients are for noise abatement considerations. However this can lead the unwary into comlacency when they need to be alert.
I have issued Cat B briefs for all airfields with minimum SID gradients that require terain clearance. The briefs include a set of parameters (TOW and Temp) up to which our aircraft can achieve the min SID gradient with an engine failure and engine anti-icing on. If the take off is outside these parameters then the Captain is obliged to consult the AFM before departure. Your AFM or Ops manual should contain a graph of groundspeed vs rate of climb shown as a gradient. There is some guidance on this in JAR-OPS but I do not have the reference on me at the mo.
If you do not have gradient information available in the AFM or Ops manual then it may be wise to consult your chief pilot. But do not challenge him, ask politely and remember the CRM acronim PACE.
Climb gradients and performance are good subjects for ground recurrent training.
MM
A tutor from the D and X.