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Mike Huntaches
4th Feb 2004, 16:23
Can someone out there enlighten me as to what the term 'V2 speedup' means? (possible that its also refered to as 'V2 overspeed'). Does it have something to do with take off gradient, or effect thereof? Also in which situations that this procedure is relevant/employed in different aircraft types? Have searched but unable to find an exact reference using this definition.:confused:

john_tullamarine
4th Feb 2004, 17:44
Mike,

Try a search using the PPRuNe search engine and keywords -

overspeed takeoff, and/or
improved climb

Restrict the search to Tech Log as much of the discussion on this subject will be in that forum.

... and you should have a cup or two coffee's worth of reading to play with ... have fun ...

Story is the same .. Boeing tends to use the "overspeed takeoff" or "overspeed V2" jargon, Airbus "improved climb performance" or "optimised V2".

Minimum V2 results in somewhat below the best climb performance for the takeoff configuration but gives good runway performance .. which is good for marketing aeroplanes.

If you have some spare runway, however (and this can mean HEAPS of spare runway), you can run to a higher speed schedule and pick up a better climb gradient as a result. There are circumstances where this is sensible (more payload) and others where it is not a proposition ... the various threads will dissect the subject until you wander off in bemusement.