Low wing approach
A question for test pilots.
From my POH (172S)
"When landing in a strong crosswind, (...). Although the crab or combination method of drift correction may be used, the wing low method gives the best control."
"Normal Approach, Flaps UP . . . . . . . . . . . . . . . . . . . . . 65 - 75 KIAS
Normal Approach, Flaps FULL . . . . . . . . . . . . . . . . . . . 60 - 70 KIAS"
When approaching using the wing low method, if I want to have the same margin above stall than when approaching using the crab method, I should fly at a higher calibrated speed. Even if I knew how much higher, I would have no idea of how much my indicated speed deviates from my calibrated speed when I fly in a slip.
In practice I would fly the approach at the higher end of the recommended approach speed range if the aircraft is heavy and I use the wing low method, and I would fly the approach at the lower end of the recommended approach speed range if the aircraft is light and I use the crab method.
Nevertheless, I'm still worried about what would happen if the calibrated speed would suddenly decrease(a gust for instance) when flying the wing low approach. I'm afraid that an asymmetric stall might be more likely to occur than when flying the crab approach.
So my question is, to what extent the crab approach is safer than the wing low approach?