A-320 V Speeds
Join Date: May 2014
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According to CS/FAR 25.107(c)(2):
So how can V2 be equal to VR?
(c) V2, in terms of calibrated airspeed, (...) may not be less than –
(1) (...);
(2) VR plus the speed increment attained (in accordance with CS 25.111(c)(2)) before reaching a height of 11 m (35 ft) above the take-off surface;
(1) (...);
(2) VR plus the speed increment attained (in accordance with CS 25.111(c)(2)) before reaching a height of 11 m (35 ft) above the take-off surface;
Join Date: Nov 2000
Location: UK
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Hifly, hello. Briefly:
Airbus typically base T/O speeds on an Optimum V2/VS Ratio.
For 4 eng a/c there will be a range of ratios. For 2 eng a/c there is only one optimum ratio.
V2 is a factored value of VS which in itself is a function of weight.
Long runway, low weight high probability of unity for V1/R/2
Suggest read notes in FCOM2 (as was) or current Book 4 in the Perf/TO section.
Out of interest: Did you notice the speeds on the output from an automated T/O calculation program, or from inspection of a RTOW page. (I'm guessing the former
)
P.S. Just read yr profile. Sympatico on losing yr Cat. When I lost mine, felt like me legs 'ad gorn!
Airbus typically base T/O speeds on an Optimum V2/VS Ratio.
For 4 eng a/c there will be a range of ratios. For 2 eng a/c there is only one optimum ratio.
V2 is a factored value of VS which in itself is a function of weight.
Long runway, low weight high probability of unity for V1/R/2
Suggest read notes in FCOM2 (as was) or current Book 4 in the Perf/TO section.
Out of interest: Did you notice the speeds on the output from an automated T/O calculation program, or from inspection of a RTOW page. (I'm guessing the former
)P.S. Just read yr profile. Sympatico on losing yr Cat. When I lost mine, felt like me legs 'ad gorn!
Last edited by 4PON4PIN; 14th May 2014 at 23:07. Reason: add a p.s.
