Good afternoon everyone,

when entering distance circles for alternates on oceanic crossings, does anyone know the distances needed for the A330neo when entering the alternate fixes for 1hr and 3hr rings?

For example, for the 787X, when entering the fix info for BIKF (Rejkavik), the 1hr ring will be set as 429 nautical miles and the 3hr ring will be set at 1220 nautical miles, 1hr and 3hr distances respectively for emergency reroutes.

I expect the performances will be different for the A330neo so was wondering if anyone uses an estimate such as the mileage above or is there a way to calculate accurately the distance traveled by the neo at cruise level for both 1 and 3 hours?

Thanks in advance

one engine, two engines, still air, head wind, tail wind, mach speed,  altitude, drift down, etc etc etc

they all make a difference.

cheers  

3 hours ago, El Diablito said:

is there a way to calculate accurately the distance traveled by the neo at cruise level for both 1 and 3 hours?

Cheers, Fluffy. I was looking to see if there's a way to calculate the distances, or does the real MCDU calculate it for example. 

I read a thread from here from 2012 that had some good pointers. The distances can be found in the ETOPS section of the OFP but unfortunately the Headwind A330 doesn't have the capability to enter the range rings. Anything over 250NM and the MCDU says "Out of Range". Ah well, back to flying blind over the Atlantic.

I’m sure you’ve probably read up on things in the thread you found but basically the 60 minutes ETOPS circle is usually specifically approved for each company so varies slightly, but is based on flying for 60 minutes at the approved engine out speed , in still wind.

A currently used real world  figure for the A330-900 is 429NM

So according to Headwind the max you can insert is 256nm because the A330 uses the ETP system and FBW and Headwind have not implemented it.