PPRuNe Forums - View Single Post - Increasing CLEARWAY vs MTOW and V1
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Old 25th May 2003, 13:01
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john_tullamarine
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At the simplest level presume a baseline of balanced field length with no spare runway .. ie a critical length situation.

Daydreaming a bit .. if we were now to increase the weight a little on a BFL basis, V1 and both ASDR and TODR will increase and will exceed the available distances. However, if we now reduce the BFL V1 at the slightly higher weight, we can reduce the BFL ASDR at the expense of increasing the BFL TODR.

Provided that we address the TORR requirements, by having a clearway declared, we can take advantage of this V1 reduction to unbalance the takeoff (ie ASDR does not equal TODR) so that we can achieve the limiting ASDA while having the increased TODR contained within the clearway extension beyond the end of the runway.

As to whether the exercise is of any significant value will depend on the numbers for the particular runway, ambients, and the aircraft flight manual data... often the results are worth the effort in doing the extra sums.
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