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Will Tidmarsh 812119

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  1. Hi Andrew, The above airports I listed are just approved alternates 'in the area' of the routes you mentioned - not all of them are neccessarily within ETOPS time (which is 180minutes for our 767-300GEs). To calculate ETOPS distance in still air, we multiply 180mins by the single engine cruise speed (the 767-300GE uses 430kts TAS), to give the maximum distance our route may go from an enroute alternate at any one time - in this case, 1,290nm in still air. If you can find an old enroute chart of the area, a useful method of checking this would be to draw, using a comp[Mod - Happy Thoughts], 1,290nm range circles on each enroute alternate airport listed above (but not the emerg ones, which can't be used for ETOPS, but can be used in a dire emergency!). In order to check that your planned route is ETOPS180-compliant, verify that at all times it lies within at least one of these circles. If it doesn't, you'll need to adjust the route so that all sections remain within a circle. Whilst inflight, you an put each of your ETOPS airports in the 'Fix' page as your flight progresses, and check that at no time are you more than 1,290nm from the nearest alternate. I fly the 744 which doesn't have ETOPS considerations, so I'm not as 'up' on it as I once was. Nonetheless, the concept is reasonably straight-forward, especially with new aeroplanes such as the 777 achieving record ETOPS times (200 mins ++) by virtue of their high reliability. That said, we regularly fly across the Pacific, and there's an area roughly halfway between Pago Pago-Tahiti and Los Angeles at which point you're at least 3 hours from the nearest alternate - not somewhere I'd like to be in an engine-out twin Fire away with any other questions - I have all the material here to look it up from. Cheers, Will
  2. No worries Andrew. Many factors are involved in selecting appropriate enroute 'normal' alternates versus emergency-only alternates - some include: - fuel availability - ground handling availability - military restrictions (eg the various US Pacific atoll military bases and installations) - pavement strength limitations - apron space etc Therefore whilst all airports listed might be technically suitable for an aeroplane to land at in a one-off emergency, some airports (the non -'emerg' ones) are preferred by the company where the situation isn't absolutely critical. Hope this helps! Will
  3. Hi Andrew My airline uses these for the 767-300 along or near the routes you described: Between NTAA Tahiti - NZAA Auckland: NCRG Rarotonga NFTF Nuku'alofa (Emerg Only) NSTU Pago Pago NSFA Faleolo NFFN Nadi NWWW Noumea YSNF Norfolk Island (Emerg Only) Between Honolulu PHNL and Tahiti NTAA: PHJR Kapolei PHOG Kahului (Emerg Only) PHTO Hilo PLCH Christmas Is/C[Mod - Happy Thoughts]idy (Emerg Only) NSTU Pago Pago NSFA Faleolo NTTG Rangiroa (Emerg Only) NTTO Hao Island (Emerg Only) NCRG Rarotonga Cheers, Will
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