A340driver,
Sec. 25.107 Takeoff speeds.
(a) V1 must be established in relation to VEF as follows:
(1) VEF is the calibrated airspeed at which the critical engine is assumed to fail. VEF must be selected by the applicant, but may not be less than VMCG, determined under Sec. 25.149(e).
(2) V1, in terms of calibrated airspeed, is selected by the applicant;
however, V1 may not be less than VEF plus the speed gained with critical engine inoperative during the time interval between the instant at which the critical engine is failed, and the instant at which the pilot recognizes and reacts to the engine failure, as indicated by the pilot's initiation of the first action (e.g., applying brakes, reducing thrust, deploying speed brakes) to stop the airplane during accelerate-stop tests.
You are correct in saying that the “defined” critical engine doesn’t apply to twin engined jet aircraft, primarily because the aircraft was tested in perfect conditions with NO WIND.
Are we therefore right in allowing VMCG limited V1 speeds when there is a crosswind ?
Would love to continue, but I have an appointment with a pint of Guinness in the Irish Village.
Mutt.