Watching several real 747-400 cockpit takeoff videos, I notice the captain will advance the throttles, wait for the engines to stabilize, then press the TOGA switches to engage the autothrottle. After a few seconds, the F/O calls out something that sounds like "Fifty percent", to which the captain responds, "I have control". These exchanges are made before the standard '80 Knots' callout. I'm surmising this initial takeoff callout has something to do with manually backing-up the autothrottles perhaps?Also, I may be misunderstanting the 'Fifty percent' callout as the crews in these video are all very British and, consequently, speak with British accents. If only they had the courtesy to speak the King's english! Ahem, well actually, I think the reason I sometimes have difficulty understanding them is that they ARE speaking the King's english. Either way, there is such a thing as over-refining the english language to the point that nonone can understand it properly!

Actually they call: "Take off thrust set" after the TOGA switch has been pressed. The "I have control" comes together with the "80kts" call. Atleast this is how Virgin Atlantic does it.Martin

Martin is this for FO take offs?Does the Captain set the thrust and have control up until the 80kt call and then the FO takes over (for a FO handling sector)?CheersSteve

Steve,the standard virgin call the captain makes for a right seat take off is"my thrust leavers my brakes,your controls"it is the capt and only the capt that makes the decision to reject or continue the take off. if there`s a reject control reverts to the capt to carry out the RTO if he decides to continue FO retains control.Each airline will have there own proceduresregardsJon