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Old 6th December 2002 | 11:32
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Hew Jampton
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Joined: Apr 1999
Posts: 220
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From: UK
The PAPIS 'correct' angle is there for a purpose and that's to indicate an approach path that gives internationally-agreed safe obstacle clearance. Yes, a shallower approach angle can give an earlier touchdown and shorter landing distance but it also increases the risk of hitting an obstacle or touching down in the undershoot area, both of which can shorten careers rather than landing distances, to say nothing of the consequences of the 'accident' itself. If you have access to a confidential reporting system like UK CHIRP or an equivalent in-house scheme, use it. It is an unfortunate fact of life that if your captain screws up and it is shown that you sat there and did nothing, especially if you knew that it had been happening "consistently", some of the fertilizer that hits the air conditioning will come your way.

On 'the step', doubtless the aerodynamics experts will comment but I think it only applies if flying near the very bottom of the drag curve, ie at max endurance speed. If the bottom of the curve is a U shape, with the very bottom being max endurance, there will be two speeds for a given power setting just above max endurance power. One of these will be 'on the back of the drag curve', ie inefficient and the other will be on the correct, efficient, side, probably at or near max range speed. 'Getting on the step' involves a belief that this practice ensures the aircraft is on the right side of the drag curve. However, especially with the advent of TCAS and level-bust monitoring both from flight recorder and radar data, I think it is wrong deliberately to bust a level, even temporarily. If it becomes part of a company's or an individual's unofficial SOP to bust the level by, say, 300 feet and the Pilot Not Flying routinely ignores it because "It's just to get on the step", one day it will be a proper level bust, ie complete failure to level off and it will have been ignored by PNF, even if PF has pre-announced his/her 'step' intentions. Again, you might consider submitting a confidential flight safety report.

Last edited by Hew Jampton; 6th December 2002 at 11:46.
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