Procedure Design Gradient (PDG) 1

28.10.2004

Submission:

Being familiar with the JAR OPS criteria for net flight path for E/Fail after V1, I wonder ,

-if there are minimum design gradients for a SID (all Eng), and

-if there are minimum design gradients for a M/A Proc (all Eng)

as standard minimum design gradients (no special terrain or noise abatement situation).

The modern Takeoff Performance Calculation tools show an EngOut Climb Gradient (gross). Knowing the climb gradient of a SID would enable the pilot to compare the estimated vertical EngOut flight path with the design gradient of an all Eng SID. This might be especially interesting at airports, where no EOSID is published.

Knowing the design gradient of a M/A Proc would enable the pilot to estimate the vertical EngOut flight path when following a M/A Proc (interesting for single engine emergency overweight landings with balked landing). As the Approach Climb Limit Weights are based on a EngOut climb gradient of 2,1% (CAT II/III 2,5%), I assume that the terrain clearance must be assured from MDA/DH by following the 2,5% climb gradient.

F. Brenner Training Captain.

Answer or Commentary:

(I.W.

Yes there are minimum gradients for all engines operating in both cases. For a SID the minimum is 3.3%, whereas for a missed approach the usual is 2.5% but can be reduced to 2%. Both cases are with out taking into account obstacles which quite often raise these values)