Optimum flaps for takeoff
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Virtually every airline would use optimum as an SOP now, The performance data for most companies is set to exclude F1 for -800/900.
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Application calculates the best scenario, and optimum flaps are being used in most of the cases, even though , if compare fuel used Flaps1 nad Flaps 5 TKOF on NG the difference reaches 80kg accordingly. For specific scenarios or airport you can choose fixed flaps ....
and optimum flaps are being used in most of the cases
Only half a speed-brake
How much of a higher EGT would you scarifice for a lower tyre speed? There must be a break-even point, I guess. But maybe I am just allergic to mis-applications of the S word. 
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Optimum flaps often requires higher takeoff speeds; therefore higher tyre speeds. Higher VR speeds than necessary increase the chances of tyre failure. High speed tyre failure on limiting runway length increase the chances of an over-run if the pilot decides for whatever the reason to abort the take of run. Especially as loss of braking efficiency will occur with tyre failure. No brainer for the safety conscious pilot especially if runway wet
do you have any reference material to support the suggestion of increased liklihood of tyre failure with the higher Vr? Having done a fair bit of research into tyre dynamics at university I am not sure where that comes from. It isnt supported from anything I remeber from those days and would be interested to see the reasons for it. Marginally increased wear I could understand but if you remain within the stated performance envelope of the tyre I dont understand what is failing.
honest question, not fishing..
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hello Centaurus
do you have any reference material to support the suggestion of increased liklihood of tyre failure with the higher Vr? Having done a fair bit of research into tyre dynamics at university I am not sure where that comes from. It isnt supported from anything I remeber from those days and would be interested to see the reasons for it. Marginally increased wear I could understand but if you remain within the stated performance envelope of the tyre I dont understand what is failing.
honest question, not fishing..
what happened to these tyres?
do you have any reference material to support the suggestion of increased liklihood of tyre failure with the higher Vr?
That is, do not abort for a tyre failure if the failure occurs at speeds more than V1 minus 20 knots. Loss of braking efficiency means V1 as a decision speed becomes invalid. MD would not have issued that warning unless there was evidence that tyre failures at high speed have happened. MD did not supply individual details.
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That is, do not abort for a tyre failure if the failure occurs at speeds more than V1 minus 20 knots. Loss of braking efficiency means V1 as a decision speed becomes invalid. MD would not have issued that warning unless there was evidence that tyre failures at high speed have happened. MD did not supply individual details.
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My company has dabbled with the fixed versus Optimum Flap for A330/340 fleet for some time. Tail strike avoidance was one reason given by the fixed flap fans. At the end of the day, it's all just silly really. The manufacturer wouldn't have called it optimum if it wasn't that. Train your pilots properly and use Optimum Flap. In the 2 yrs since moving back to Opt Flap, we haven't seen any tail strikes, or increased tire failures for that matter.
