Performance: "VMCA" and "Vs" or "Vsr"

[wiw3bb3r]

Hello everyone !

I was studying performance through a book called 737 Performance Reference Handbook, by Maurits Hulshof.

The book says that VMCA should be 1.2 Vs (1.13 Vsr) OR GREATER, "according to the FAR 25.149"

If you look at the FAR 25.149, it says that VMC may NOT exceed 1.13 Vsr

So which one should be followed? This is taking my sleep!


Thanks in advance !

[Mad (Flt) Scientist]

V2min is required to be at least 1.2 Vs (or 1.13Vsr, as applicable) per the various versions of 25.107(b) (With those numbers being for jets, turboprops use different factors)

V2min also has to be at least 1.1 VMC, also per 25.107(b)

Someone has managed to mix the VMC and V2min requirements. The FAR (and CS, and ...) are the definitive source. VMC has an upper bound, not a lower one.

[wiw3bb3r]

Ok, perfect. Thank you !