Moggiee
Moggiee,
You say :
“There should not be a gap between VMCG and VMCA. V1 must ALWAYS be lower than either of these speeds so that the loss of the critical power unit does not lead to loss of control.”
Well, when I used to fly, Vmcg was a ground speed and Vmca was a flight speed, so I am not quite sure what your understanding of V1 is ?
Also :
“For 3 engined take off the performance is calculated on the understanding that the second engine will fail at V1 and the take-off will be continued”
I always thought V1 was a recognition speed ? And I must say my understanding was quite different to yours, but it always worked fine.
Try these definitions :
Vmca MINIMUM CONTROL SPEED (AIRBORNE)
Vmca is the minimum flight speed at which the aircraft is directionally controllable. The conditions for Vmca include the critical engine becoming inoperative and windmilling, using a maximum of 5° of bank towards the operating engine, which is at maximum thrust, landing gear up, flaps set at take-off setting and the most rearward CG.
Vmcg MINIMUM CONTROL SPEED (GROUND)
Vmcg is the minimum control speed on the ground at which the take-off can be continued using aerodynamic controls alone, when the critical engine suddenly becomes inoperative and the remaining engine(s) are at take-off thrust.
These might have altered slightly ? Long time since I saw four thrust levers on one console.
V1 – can’t remember it exactly, but in practice it is a historical speed as you make your mind up to go long before it arrives
Ferry Dude, Thanks for bringing the topic back on line.
oTd