Will you climb at Vxse or Vyse with 1 engine out after take-off on a twin Jet ?

[manucordier]

Hi,

Could someone tell me at what minimum IAS one must climb if you get one engine inoperative during the climb (after takeoff) on a two engine jet aircraft (B737 or A320 for instance).

On a piston twin engine (I did my ME on a Cessna C310R) I remember we had to climb at Vyse (= blue line) which is the speed that gives the best rate of climb with one engine out. However, I suppose that if I have nasty obstacles ahead of me I would rather fly Vxse, which is the speed that gives the best angle of climb one engine out. Vxse is a bit slower than Vyse.

Would that be the same reasoning for a B737 or a A320 ?

Thanks for your help.
Good night.

[George Koumis]

Hi manucordier,

Well, the philosophy in a commercial airliner is a bit different from the C310.

When, for example, you encounter an engine out in an A320 right after Take-Off, your first action is to maintain a positive RoC by following the Flight Director Commands (Pitch Up about 12,5 degrees). This pitch would give you a speed of about V2 + 15. V2 depends on multiple parameters (runway, weight, wind, configuration, etc).

You follow that speed for as long as it gets to secure the engine, depending on the failure (Engine Fire, Catastrophic or Not).

Hope it helps somehow,

george