Operational Requirement to increase VMCG by 5 knots if either ADP 1 or 4 is MEL-for ADP 2 and 3 does not have requirement. Can anyone tell me what the performance issue is. ENG 1 and ENG 4 can either be critical engine but still have rudder authority with loss of engine 1 or 4 if adp is u/s. Upper rudder systems 1/3 and lower rudder 2/4. Can't seem to figure out the issue of controlability. Any suggestions or ideas why required for ADP 1 and 4 and not for ADP 2 or 3. I know there is issue with gear after rotation for 1 and 4 but on ground? Thanks
