B737 N-1 Flaps 10 circling, why?

[hoek0201]

Dear all,

Can anyone explain the reason why Boeing wants flaps 10 for a B737 N-1 circling? I can understand why we wait with gear down, flaps 15. But if it is to increase maneuvre margin why not use it on a normal circling as well?

Thanks in advance,

Kirk

[john_tullamarine]

Never looked into this specifically but, probably, for OEI 10 deg provides for the approach criteria while 15 deg does likewise for landing.

[RAT 5]

Which B737? ON NG's F10 is same speed as F5 but more drag, so doesn't seem a good idea. On the classic with fixed speed schedules for flaps, F10 will give you a reduced IAS and at max wt. bring you within Cat C circling minima. At high wt's. F5 might take you into Cat D and perhaps higher minima. You'll need to check the speeds; I don't have them to hand.

[hoek0201]

It's about NG's, it's in our FCTM. Recommended to use 10 optional 5.

Kirk

[FCS Explorer]

maybe to get a better visual segment?