Richard 111
A "ball park v2" what is that ? Either there is a correct V2 or there isn't. If you were using de-rate take offs on the 777 then if you select TOGA you will likely crash. Which is why Boeing say don't do it. A new VMCA is calculated using the selected de-rate. You will run into controllability issues if you push TOGA on the remaining engine. Assumed temperature can be cancelled without an issue so you may push the thrust levers forward but only to the de-rate limit which is why you have the show full option on OPT. Your company should revise that SOP with the Boeing technical team. The 787 is identical to the 777 in this regard although it also has TAPS/TAMS to try to stop you crashing.
So to summarise if you takeoff with De-rate and ATM combination you may disconnect the A/T and push to the selected De-rate limit only......but NOT TOGA ! Yes the 787 has a drastic drop in performance with an EFATO compared to the 777 but it is all still compliant with the regulations if you fly it correctly. The 777 has more margin but then its a 26 year old design and designed for anything from 155 to 351 ton take off. The 787 is strictly a min fuel burn machine.
By the way our E/O acceleration is 1500 AGL so it can be a very long wait on the 787
Last edited by 8che; 17th Dec 2016 at 16:33.