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Old 31st May 2008 | 09:06
  #5 (permalink)  
enicalyth
 
Joined: Jul 2004
Posts: 513
Likes: 0
From: Sydney NSW
will this do?

Never mind which variants of A340 and B747 you have in mind I wish there were such a thing as a typical day and a typical load. This question has been asked so many times on pprune I wonder what was wrong with the previous answers. Suppose we are a bog standard 744, CF-6 engines, HKG-SYD, no delays, good connections, oil is cheap and aircrew wages inflated. We’ll aim for a M0.86 cruise then in this fantasy flight. An Ocean 1C departure to make us pay attention to fly-over WPs. A ZFW of 230T and a proposed landing weight of 242T. [The fuel burnout will probably be about 88T and we have an aversion to low pressure warning lights coming on]. Let’s say we also overfly Berowra [BEROW], SY, NASHO, RISOL, SOSIJ, SIZZL. Not the most economical approach but we fly over my house in Eastwood, go down to the “Nasho”, our first and famous Royal National Park and enjoy the particular humour of Aussie waypoints. Rissole, sausage, sizzle the rissole also being our RSL club name as well as a barbecued delicacy. That is a journey of 4100nm with no wind factor applied and will take 8.8hrs so the first rule is roughly 10T per hour. Re-hashing the weights the BRW is about ZFW+100T giving a figure of 330T. The first variable is climate and ATC and I am going to simplify everything into a world where you fly odds southbound and evens northbound purely because at this weight the B744 settles at its happiest into FL330 at first cruise in 130nm, 18 mins and 8T gone up in smoke. A fairly hot muggy day then. At M0.86 [CI, what’s that??] she’ll turn over 2800kg/hr/eng easily. And somewhere around 295T AUW the green screen will say NOW and we punch up to FL370 and 2500kg/hr/eng and stay there until 2200kg/hr/eng at T/D. Slide over SY at 6,000ft, no mistaking the CBD and Coathanger where in the Rocks the “Lord Nelson” and “The Hero” will welcome you with open arms, if you have an open wallet. Slowing for a tight turn NASHO-RISOL and home it isn’t the most economical descent and can wipe out 2T over 130nm but it sure is pretty. Take time to visit the real Nasho. Take the train to Otford and get the worst part of the climb over first. Ignore the signs to the nudist beach and trek through Burning Palms. When you reach the settlement ask for Pedro, he’ll have a few spare bunks and his pot of tea is awesome. It’s an easy walk north to the ferry now, on your 2nd day, time to take in the aboriginal rock carvings on the way. You can hail the refreshment boat and it drives right up to the beach for teas, ices… whatever. Of course with different engines, a dimpled airframe, different loads everything is different. There really is no exact answer. Point is don’t stay up in the air, get your feet on the ground, your belly outside some good barramundi, a decent stubbie in your hand and forget the interview. Get married, have kids, sail nothing less than a 40-footer and drive only a Toyota HiLux. Retire at 55. When you ask a general question you get evry shade of answer. Mine includes lifestyle. Enjoy yours, there's only 25yrs till the big excrement fight breaks out. And with that happy thought I'll get my coat...

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The "E"
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