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Old 12th April 2002 | 09:16
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john_tullamarine
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Joined: Apr 2001
: ATPL
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From: various places .....
Alex,

Re the L1011 V2, a manufacturer doesn't have to use a min V2 schedule and, if the commercial considerations are appropriate, a modest overspeed might have been scheduled to provide a better WAT limit at the lower values of Hp .. particularly if the specific aircraft/model has high performance brake units so that a higher V1 can be tolerated in parallel .. there is not much point in going overspeed on other than a long runway unless the V1 can be pushed up as well. In the absence of an AFM I am only speculating .. but Mr Lockheed might be reducing the V2 from a slight overspeed schedule as Hp increases the better to get an optimal weight ?

I presume that CAP698 is a study guide document of some sort using a "typical" aircraft as an example. Not having that document I am not able to offer any additional comment. However I am never comfortable with these generalist questions as one has to put too many qualifications to any answer ... or else the answer becomes a rather lengthy and boring dissertation ... additionally VR and V2 considerations correlate better with T/W than a simple consideration of thrust.

.... and ... if only the real world decision to abort were as simple as it might be presented in the ATPL lecture classroom ....
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