Ask Captain Lim ~ All about Aviation

Dear Captain Lim,

Firstly, I do sincerely appreciate your dedication, effort and time to create such an informative and excellent website for us. I can really feel your passion about flying and I know you do enjoy your job in the sky.

After I read your FAQ about engine failure on the Boeing 777, I have one more question. Let's say, if you decide to proceed with the take-off after one engine has failed before the aircraft reached V1 on a short haul flight of about 2 hours, I would like to know, whether you would fly to your destination as scheduled or would you join the circuit and land in the departure aerodrome?

I am looking forward to your reply. If it is possible, could you also share some more technical and operation stuff with us?

Thank you.

Regards,

Ben Lam

Hi Ben,

I think there is a slight misconception on the issue of V1 - the decision speed. Let me refresh.

V1 is the take off decision speed whereby if the take off is continued after an engine failure (above this speed) it will be possible to continue the take-off safely. It is also the speed whereby, if the Captain abandoned the take off, it will also be possible to bring the aircraft to a safe stop within the remaining Runway.

This means that an airplane must be ABOVE the V1 speed before he can safely continue with the take off if an engine fails. If the airplane has NOT reached the V1 speed, he MUST ABORT the take off for it is no longer safe to do so. So in your scenario, the Captain would abort the take off.

However, if the engine fails ABOVE V1, the Captain would continue the take off, carry out the emergency drills and attempt to re-start the engine. If it is not possible to regain the failed engine, he would return for a single engine landing and would NOT proceed to the destination. On the other hand, if the engine fails past the half way point, the Captain would only continue to fly on one engine to the destination or any diversion airports if he chooses to do so.

Sorry, general operational and technical issues are too wide to cover in this site!