Vtgt on final B737-6-7-8
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Vtgt on final B737-6-7-8
Hello,
following question: What is your experience in maintaining Vtgt or vref+ x on very short final. i sometimes realize that when i go to the visual part the speed is going up 5 knots or so over the vtgt. i fly on speed till 200ft and then i think the thrust is to much,but i did not change the levers!some instructors on the 737 want us to fly faster instead of marginal vref+5.
how are you handling that thing?
thansk
OD
following question: What is your experience in maintaining Vtgt or vref+ x on very short final. i sometimes realize that when i go to the visual part the speed is going up 5 knots or so over the vtgt. i fly on speed till 200ft and then i think the thrust is to much,but i did not change the levers!some instructors on the 737 want us to fly faster instead of marginal vref+5.
how are you handling that thing?
thansk
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No pilot, but you will be experiencing span dominated ground effect at about 1 span altitude - or about 100' AGL and down on a 737NG.
This ground effect will reduce your induced drag due to less vortex build-up - giving you a slight speed increase if thrust is constant.
Cheers,
M
This ground effect will reduce your induced drag due to less vortex build-up - giving you a slight speed increase if thrust is constant.
Cheers,
M
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Are you sure when you go visual you are not letting the nose drop slightly? It is very common and I have to say I still do it if I don't concentrate.
Once you are sure you are not making that mistake, it's correct you will start running into ground effect which can cause this. I used to find on the 747 it was necessary at about 400' in a perfectly stabilised approach to pull a small amount of thrust off to prevent this happening. If your speed is stable, try this at about 200' every time, it should work. You do not want to let the speed go up, keep on target- it is a very slipery aeroplane hard to land- if you have higher speed you make things very difficult for yourself.
Once you are sure you are not making that mistake, it's correct you will start running into ground effect which can cause this. I used to find on the 747 it was necessary at about 400' in a perfectly stabilised approach to pull a small amount of thrust off to prevent this happening. If your speed is stable, try this at about 200' every time, it should work. You do not want to let the speed go up, keep on target- it is a very slipery aeroplane hard to land- if you have higher speed you make things very difficult for yourself.
