Concorde question on diverts

[newswatcher]

Had a conversation with an ex-BA pilot yesterday. He told me that, for a 20 minute period on the flight from London to Barbados, there are no suitable diversions in the event of a major engine failure.

Am I missing something here? Would anyone like to clarify this, since it sounds unlikely? :confused:

[mach2moose]

newswatcher,

Flights to BGI are constantly monitored by the crew to ascertain the nearest diversion airfield in the event of a single or even double engine failure.

There is always a suitable diversion although for about 20 minutes in the middle, a decision must be made PDQ if you are to arrive with legal fuel, in the event of a double engine failure.

m2m

[newswatcher]

thanks m2m, I didn't think that the CAA would authorise this routing if such a situation existed. Sobering to think that, in 20 minutes, 450 miles will be covered!

Who am I to argue with an ex-Nigel?!?

[Bellerophon]

newswatcher

As you seem to suspect, it is complete rubbish.

As well as loading sufficient fuel to arrive at BGI with standard fuel reserves, enough fuel must also be loaded to meet the tactical requirement that, following an engine shut-down at any stage in the flight, Concorde can still divert, on three engines, to a suitable diversion airfield, and arrive there with standard fuel reserves still remaining.

The main difference between Concorde and other subsonic aircraft in a similar situation is that Concorde will suffer a much more substantial loss in range. From four-engined supersonic flight to optimum three-engined cruise there will be a loss in range in the order of 30-35%.

This is mainly because Concorde must now leave a very efficient flight regime, at M2.0 and 55,000-60,000ft, with relatively low drag, low winds and very cold outside air temperatures, for a higher drag subsonic regime at M0.95, at around 30,000ft, with warmer outside air temperatures and much stronger, probably adverse, winds.

The forecast weather at the principal en-route diversion airfields of Santa Maria, Lajes, Bermuda and Antigua, along with the calculated subsonic wind components to these airfields, are all taken into account at the flight planning stage.

If the weather conditions at and en-route to these diversion airfields are favourable, flight planning is straightforward, if the weather conditions adverse, flight planning gets somewhat more difficult, but the necessary fuel will always be carried, or a re-fuelling stop planned.

On Concorde, the LHR-BGI route is the most demanding and it does requires careful planning and good tactical awareness, but the flight planning procedures are standard, and any twin-jet ETOPS rated pilots would find that they were very familiar with all the planning processes and tactical decision making involved.

With one exception.

Concorde will be able to get you to a diversion airfield after a second engine failure! :D

Regards

Bellerophon

[scanscanscan]

Sadly a concorde on two engines ex CDG did not.

[foxmoth]

SCAN - that was a bit more than just an engine FAILURE!
Bellerophon - ok you have the advantage on double engine failure, but how much is a decompression taken into account (worst case scenario on ETOPS)?

[gordonroxburgh]

scanscanscan

I can't think of many 4 engined aircraft at MTOW that could get away with a double engine failure at take off.

At CDG the aircraft was also burning badly, effecting controllability amongst many other system.

[Bellerophon]

foxmoth

The Worst Case decompression scenario is covered on Concorde, on all current routes, with no extra fuel needed to cover this eventuality.

By comparison with modern subsonic aircraft, an unusually large fuel penalty is suffered on Concorde, following the loss of an engine in cruise, which will necessitate a change in flight regime, typically from 4e, M2, FL520, to 3e, M0.95, FL290.

This fuel penalty is so large, that it is similar to the fuel penalty suffered by going from 4E, M2, FL520 to 4e, M0.76, FL140 following a decompression.

Concorde maintains not only a 3e diversion capability from any point in the flight, but also a 2e diversion capability, and as the fuel required to cover the decompression scenario is less than the 2e diversion fuel, decompression fuel, whilst always a consideration, is not an issue.

Once down at FL140, at M0.76, following a decompression, an engine failure at this stage would hardly affect the total fuel flow, and range would be unaffected.

I wonder, would that apply to your Airbus? ;)

Regards

Bellerophon

[Tonic Please]

Whats all this 4e and 3e business about ??

[sss]

uneducated guess 4e - four engine, 3e - three engine.