SFI145
17th Apr 2007, 11:03
If a SID has a required climb gradient (e.g. 5% up to 5000 feet) do operators have to treat this as a dummy obstacle for performance calculation purposes or is an escape manoeuvre sufficient?
john_tullamarine
17th Apr 2007, 14:14
Perhaps you have answered your own question ..
(a) if you intend to fly the SID, then the dummy obstacle approach is sensible
(b) if you intend to bug out, then the SID becomes irrelevant
Old Smokey
18th Apr 2007, 07:28
It depends upon whether you are considering the All-Engines Operating (AEO) or 1 Engine Inoperative (OEI) scenario.
If you are talking of a normal AEO departure, you must ensure that your aircraft's AEO performance is such that you can meet the SID Gradient requirement.
Having established before departure that you CAN meet the AEO requirements for the SID, you must now establish a suitable OEI 'escape' from the SID, which mostly leads to a totally different lateral and vertical profile to the SID.
SIDs are calculated from PANS-OPS (and their equivalents) rules, OEI procedures are calculated from FAR 25 (and their equivalents) rules, totally different sets of rules, and........ BOTH MUST BE SATISFIED!
.... and that probably generates more questions than answers :E
Regards,
Old Smokey