Sleeve Wing , concur with avoiding water / slush /snow ingestion . We used same technique on all marks on Trident .
In those conditions ,
''V1'' called and is stop /go decision speed .
''Rotate'' called at rotate speed [ Vr ] .
''V2'' is engine out safety speed . In wet conditions , gives a screen height of 15 feet! Talk to BAC111 crew out of Basel on a wet day with and engine failing after V1 ...
With the modern twins , they are mostly way over powered in the 2 engine t/o case , and thus very often V1 = Vr .
rgds condor .