Gross And Net Flight Path

Question 1

Net flight path NFP

Brenner

Answer 1

A margin of 35 feet obstacle clearance. FAA mandates an aircraft must clear all obstacles within an Obstacle Accountability Area by 35 feet by its lowest point, usually the wing tip. EASA mandates 50 feet in turns greater than 15 degrees of bank.

Question 2

Gross Flight Path GFP

Brenner

Answer 2

NFP + margin of safety of
0.8% for twinjets
0.9% for trijets
1.0% for quadjets