Question for OS.
How can a take off be accel stop limited in isolation? I can always stop below v1 so by reducing v1 i can declare a higher stop limited weight.
For the go case as weight increases for a fixed TODA v1min must increase.
If I plot the go line and the stop line where they cross must be the OEI runway limited weight.
adding clearway moves the go line such that i can have my failure at a lower speed and still go. Now where the go and stop lines cross is at a lower speed (v1) and a higher weight.
V1 is for stopping or going but we could well have a V1min defined by go and a V1max defined by stop. Clearway has no effect on V1 max but will reduce V1 min so long as it isn't limited by something else. (VMCG)
Airbus explain this from the V1 perspective in their getting to grips series as follows:
For a given takeoff weight, any increase in V1 leads to a reduction in both TODN-1 and TORN-1. The reason is that the all engine acceleration phase is longer with a higher V1 speed, and, consequently, in case of an engine failure occurring at VEF, the same V2 speed can be achieved at 35 feet at a shorter distance.
But it's saying the same thing. Increase V1 leads to reduction in TOD n-1 is the same as increase TOD n-1 leads to reduced V1.
But I'm open to another interpretation.