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View Full Version : Vref and all that.


Centaurus
7th Sep 2002, 14:32
How things change over the years. When I flew the 737-200 12 years ago Boeing stated that on landing approach the headwind wind additives (not the gust factor) were bled off such that the aircraft crossed the threshold right on Vref. Touch-down was around Vref minus 5 knots.
More recent Boeing publications say that you cross the fence with the HW additives which you apparently lose in the flare (lose 10-15 knots on the flare - no way unless you float for miles) and touch down at Vref.

I don't see the problem. Why do people get so apprehensive of getting close to the calculated Vref speed approaching the threshold? Is it because of scares that third world pilots may get below Vref too early? I once was told by a Boeing instructor pilot many many years ago that Boeing plan for the weakest link.

Pilot Pete
7th Sep 2002, 16:27
Just an idea; is it perhaps for commonality between types (especially versions of 737)? I know from personal experience (!) that if you get below the Vref at all on the 757 it drops on pretty damn hard!

PP