As you know the industry paid attention to 'slush'after the BEA takeoff accident late 50's.FAA take into account 'slush'and data available in the AFM.the difference between FAA data and the JAR's is the 'wet' screen height adopted by the BCAR,thence the JAA.With 'Contam'ops,JAA rules reduce the screen height to 15'and the V1 is reduced to enable the accel'stop! to stop in the distance provided.As the UK has always contended it's a compromise towards safety.The same 'info'is now avail'to Boeing User's under 'perf package 'B',used by all the JAA fleets!It cost money and in the gen'case'payload-but it is Safer.Why is this Safer procedure not used in the 'states-because the ATA(fleet owners)won't compromise on the payload,and the FAA won't use the 'new'data(B777)on the 'old'types..
