Posted by Dogma
This post illustrates perfectly why not to ask technical questions on this type of forum.
Granted you have made some accurate observations but some of this is utter drivel:
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Vr is 1.3 VS, Simple as that.
V1 is a function of the accelerate stop capability of the aircraft on the day.
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I'm sorry, but
your info above is far more misleading.
Vr has No rpt NO relationship of that nature with stall speed. I don't know where you can have got such a wierd idea. One of the regulatory minima for V2 (which is always higher than Vr) is 1.2Vs. There would be no point in defining this if Vr were always 1.3Vs.
V1 may or may not be a function of the accel-stop performance; it depends on the aircraft and the conditions, as do issues of whether Vmc or Vmu are limiting for determining takeoff speeds.
edit - OK, I think I can guess where you are getting that idea from...
Vr is rotation speed (and is the subject of all the above discussion)
Vref is defined as not less than1.3Vs (note it need not be equal to 1.3Vs) and I suspect that's what you are bringing into the discussion.