BOAC-indeed ,I'll reach more quickly v1 (53t) ,but in case of reject-actual weight is 48T-lower braking force comparing to 53T-so maybe overrun. The v1 for 48T can be 10kts lower than v1(53T).
In case of improved climb we have calculations done,but just ot take v1 for max TOW for any lower TOW doesn't seem safe to me.Why all the calculations then,just do one for max TOW?
The assumed 50C guarantees you'll stop for a TOW of 53T if you use the V1 for 53T.If you're lighter than 53T shouldn't you use corresponding v1?