Qrh 2.32 & 2.33
After giving this some thought and discussing with sim instructors...........
From QRH 2.38A
Only combine PRIMARY or SINGLE failure....this is the key sentence !!
So if you have a G + Y hyd failure, then the "direct law" additive is NOT considered a PRIMARY failure.
So the calculation of the LDA require @ 66T will be
910 x 2.8=2548m which is pretty close to answer in summary table.
Next query comes to mind. Would I be correct in saying that there are 9 primary failures that require LDG distance calculation from chart 2.32 ans 2.33 QRH.
The primary failure being
1.ELEC
2.SLAT/FLAP
3.FLT CTL
4.HYD
5.A.ICE
6.BRK
7.NAV
8.BLEED
9.ENG
Any comments on my thinking ????
regards