PPRuNe Forums - View Single Post - All Engines Go Around from runway well below Vref
Old 21st Feb 2009, 18:04
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Mad (Flt) Scientist
 
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Originally Posted by Old Smokey
To put you in the comfort zone, 15 Kt below Vref for a B737 should still be above the stall, so the aircraft is flyable.Remember that Vref is 1.3 X Vs, whereas V2 (min) is 1.2 X Vs, so, although we don't have V2s for Landing Flap, a speed a bit below Vref should be no more dangerous (from a stall point of view) than for a Takeoff. If for example, Vs was 100 Kt, V2 would be 120 Kt, and Vref 130 Kt, so 10 Kt below Vref is totally survivable.
I won't presume to debate the techniques, but one caveat on the comment comparing Vref-10 to V2: For the takeoff case your engines are already running at the power you want - if you've ended up well below Vref, there's probably a good chance that your engines have been brought to idle, or close to it. As a consequence, the engine response will be rather sluggish on many jets, especially turbofans.

As a result, if you fly the balked landing like a takeoff, you're going to be very short on energy. This accident in Fredericton contains some of those elements. (Section 1.18.1.4 discusses the go-around/balked landing specifically)
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