…Does an aircraft with 4 engines have to land, when one engine fails ?…
In most cases of a single engine failure on a four-engined jet, in the absence of any indications of a fire, the flight will continue on towards destination and the aircraft will not land at the nearest airport. The passengers may well not know that an engine has been shut down unless the crew elect to tell them.
In general terms, prior to making the decision to continue towards destination, the main items the Captain will check are:
That sufficient fuel is on board to continue towards destination, at the increased fuel consumption and lower cruise level of a three engine cruise.
That a suitable airfield will always within range of the aircraft's intended route for an immediate landing should a second engine fail.
That the aircraft will be able to clear any high ground on its intended route should a second engine fail.
That there is no reason to suspect that the reason the first engine failed might also affect the remaining engines.
The weather and route will of course play a large part in the Captain’s decision. It will be a harder decision for a B747 Captain who is flying over the Pacific in poor weather than for one who is flying over Europe in good weather.
If the fuel situation does not permit continued flight to destination, then at least a landing can be made at a convenient airfield, close to destination where good engineering, passenger handling and company facilities exist.
A B747-400, on a SIN
flight, lost an engine on take-off at SIN
some years ago. After checking all the above points the Captain decided the flight could safely continue towards LHR
Fuel checks revealed that whilst LHR
would be out of reach on three engines, Helsinki could safely be reached with full fuel reserves remaining, so the flight continued Westbound towards HEL
During the nine hours it took to arrive at HEL
, the company concerned had arranged for a spare aircraft to fly to HEL
and by the time the first aircraft landed, was ready and waiting to take the passengers on the last leg of their journey to LHR
with only minimal delay.