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brian747 posted a blog entry in Brian's Charter: 747-400 tripsThis trip came about as the result of an offline chat I have been having with Alan (WW1000) in which we were discussing the new Tours — and in particular the Long Haul Tour, in which at least some of the legs were by most standards a bit too long for an unmodified Boeing 744. I had therefore resigned myself to not attempting that Tour — until Alan mentioned that he had once done London-Sydney non-stop in a 744, and that made me think again. Obviously, an unmodified 747 (even an ER version with both additional tanks) was going to... have problems, shall we say — in spite of the fact that the ER model of the 747-400 increased the MTOW to 412,770Kg, with an auxiliary fuel tank in the forward cargo hold and an optional second additional tank in the stabilizer. But the problems I had expected were confirmed when PFPX flatly refused to release the vlight, since the amount of fuel needed would exceed the aircraft's MTOW (Maximum Take-Off Weight). But a challenge was a challenge.... Although a huge trip such as London to Sydney is normally the preserve of the Boeing 777-200LR (even an A340-500, and definitely an A380, would struggle), a little research (OK, Google) quickly revealed that a 744 has indeed done the trip IRL — as recorded in a Flight Global article from 1989 that you can read here. The QANTAS 747-40 ER made it in 20 hours and 9 minutes, just 6 minutes slower than the RAF Vulcan that still holds the record — in spite of the fact that the Vulcan had to refuel in mid-air four times during the trip ;-) . QANTAS's record attempt was made to herald the arrival of the (then) newly-introduced 747-400 ER into their fleet. The flight was made possible because they reduced weight as much as they could and also had a tow to the runway threshold to save taxy fuel: however, the real key to their success was the use of "a special Shell-supplied high-density (0.84 specific gravity, 5 per cent up on the norm) version of Jet A1". I did have a word with virtual Shell, but they couldn't see their way clear to supplying me with their special fuel, so I had to use the usual Jet A-1 and resort to other means to achieve my objective. So I set about building what I mentally called "the Frankenstein 744". Basically, I set out to create a special version of the aircraft, one that would give Boeing a fit of the horrors, but which could be light enough to do the trip with an ER's maximum fuel. QANTAS used the same technique in their 1989 flight too, to be fair: although the only tweaks they revealed to the writer of the article were "...the lack of cargo containers and pallet locks, and less galley equipment". Hmm. Anyway, happily, in PSX you are able to 'roll your own' to a certain extent as long as it's consistent with reality, in that every item on Boeing's list of available equipment for the relevant model is available (or not) — hence with the ER version you can opt to have auxiliary and/or stabilizer tanks fitted — I fitted them both, and then went through the rest of the options with some care. Having thus built my monster in PSX, I retrofitted it into PFPX so that I could do the planning, and this time PFPX was willing to release a (minimum fuel) flight plan for me to import into my 744's FMC. Unfortunately, I was still left with a slight problem, since PFPX planned the minimum-fuel route like this: EGLL DET UL6 DVR UL9 KONAN UL607 MATUG UZ660 RASPU UL984 OKG L984 NIROV M991 OLGIN B494 MKL B491 BISNA M23 MARAL B450 BIBIM A909 LEMOD N644 REGET J145 DI A466 JHANG M875 LAPAN B209 JJS P646 PTN N895 BETNO G463 BKK R468 TSN M768 ELBIS DCT SCO H12 BOREE YSSY (That's the abbreviated ATC-style route, which translates to many more LEGS entries, of course). The snag with it proved to be that when I imported the route into the aircraft and it was translated onto the LEGS page, even before the DET2F SID was added the route was truncated abruptly just before entering Australian airspace. I should explain that the 744 has a slight memory problem, in that there is a top limit of 120 LEGS entries which can be held in the FMC — beyond that you get a "ROUTE FULL" message (and this is faithfully modelled in PSX, of course). So I had to do what RW 744 pilots have to do on their very long flights (I've encountered this previously many times on trips from the UK to Far East destinations, so I know the drill): make a careful note of the missing entries, and then add them in to the FMC by hand (or rather, finger) once safely into the cruise. Not forgetting, when over Australia and having received the ATIS for YSSY, adding the appropriate STAR too, which conveniently (since it meant a straight-in run) turned out to be BORE7P into YSSY's rwy 16R. A bit of a faff? Maybe, but this was an attempt at the record, after all. 8-) But could I make it? There was only one way to find out.... I took off from Heathrow's rwy 27R, followed the DET2F SID, and once I was well past Dover added the missing waypoints to the FMC for the end of the trip. (I added the STAR much later, while over Australia, once the weather and runway in use were known). Here I am over Timor and approaching the coast of north Australia. At the beginning of this you saw a map of the vlight (planned using PFPX's "minimum fuel" option). The initial cruise altitude was FL290, but to conserve fuel during the trip I step-climbed to FL310, FL330, FL350, FL370, FL390, FL410, FL430, and ultimately FL450 — which is pretty much the ceiling for a 744. (The record-breaking QANTAS flight also step-climbed to FL450 by the end of the trip). The planned time for the 1989 QANTAS journey was between 19 hours 23 mins and 19 hours 54 mins (their actual time was 20 hours 9 minutes). I was therefore anxious to do it in less than that if at all possible — hence my determined attempt at step-climbing to conserve fuel as much as I could. The only potential problem being those very high altitudes.... I have talked about "coffin corner" on the forum previously (see here and here for details) and therefore I have to admit that a step climb to FL450 was something that I accepted with some reluctance and only on the grounds of maximum fuel economy. I also monitored the vlight pretty closely (some might say, nervously <*cough*> ) for the last four hours. I did at one point push the nose down a fraction just to practice getting out of the subsequent unpleasant train of events (OK, you guessed, I was also getting a bit bored with long range cruise), and the result was immediate (see pic) — the bottom row of 'red bricks' threatened to rise into my flight régime, the speed climbed to 0.867M, the autopilot chucked me out of VNAV in disgust, and I had to repond decisively to get things back under control again before ATC noticed the departure from my assigned altitude. 8-º There was also plenty of time to observe that at FL450 (hmm, that *is* 8½ miles up, I suppose) the horizon is definitely curved. OK, the effect is being exaggerated somewhat by my wide-angle lens view within FSX, but you can get an idea of the effect nonetheless). At the Top of Descent I was happy to find that that straight-in approach to rwy 16R was definitely going to be easy-peasy. Descending thru FL200 I had just the moon and some clouds for company: Happily, throughout the trip I had benefited from some kindly tail winds that reduced my fuel usage (even during the descent they were still helping me, as you can see) — — with the result that when I'd approached the Top of Descent with just 150 nm to go the FMC was predicting that I would land with 22.5 tonnes of fuel still on board — luxury! During the long trip I had had plenty of time to decide that at the end of it I'd be using autoland (I thought it wise not to take even the slightest risk of messing up this landing, not after 19 hours): it's ages since I did one anyway, and the rules do say that I'm supposed to do one a month.... 8-º After landing, I taxyed to gate 35 in the International terminal with a certain measure of relief, and shut down. But the big question is: how long did the trip take? The official answer (according to the WV ACARS monitor) was 19 hours and 8 minutes — so a record indeed! (OK, a slightly fluky one, perhaps, but it still counts!). X-) And the aircraft's onboard ACARS OOOI agrees (even if it does seem a little confused about my departure airport??!): To be fair, I suppose I was lucky to get favourable tail winds, and, as an added bonus, a straight in approach to rwy 16R, but anyway — I made it. :-) So many thanks to Alan for the challenge! Right.... it's time to take a look at the Long Haul Tour, I think.... :-D Cheers, Brian