Mrakula wrote:trav777 wrote:Mrakula wrote:
ok, in response to both you and the previous message on this same subject- guys, I don't want to keep going round and round on this.
Feel free to use whatever ACAP you want; I'm using a real world example of an actual flight, ok? Throw your ACAP out the wiindow; we have video of a FC on an actual flight as well as SQ's data on LAX-SIN. The p-r graph is linear. If you add payload you go up it, subtract and you go down it. This is a straightforward calculation.
Again, the 268t DL 359 will not do LAX-SYD with a full cabin. Its real range is around 6600nm with 300 pax, give or take. DL's config is probably not really much lighter nor heavier than any other common airline's. The 78J's brochure range, which I'm giving a hell of a lot of accuracy to given how accurate BA's other brochure ranges now are against REAL world flight profiles, is 6400nm with 330 pax. If you subtract 3t of pax (30) you will have more range than 6600nm. This is just a simple fact.
So what is the issue with it? You don't wanna hear it? You don't like it? There's nothing whatsoever factually controversial about what I'm saying and it's backed up with not just my own but another guy's analysis on the DL/350 thread. Even taking his rounded up number of 33t payload for that leg, against the wind on the westbound, the plane does not have the range to fly full pax in DL's config.
I'm not sure why this information is meeting with so much opposition when the numbers are not in dispute.[/quote
Sorry but your estmations are totally irelevant!
You are comparing data from forum thread about DL/A350 complains with 787-10 brochure data!!!
Compare both aircraft in same environment. Ideally at same route at same time.
is there a reading comprehension problem or something? Boeing's brochure specs are accurate these days. for the love of god you can go to the 787's ACAPS and adjust on the 789's graph downward to account for the increase in weight of the 78X and see exactly where the range will be...6400. And I mean adjusted ACAP relecting the downgrade from 8200-7635nm range on the 789
How can you say that? Boeing is true but Airbus lies.
https://www.boeing.com/resources/boeing ... ps/787.pdf
https://www.airbus.com/content/dam/corp ... 0-1000.pdf
There are manufacturers performance data. It is far from real world environment but at least something exact.
I'm not sure how to get through to you...can someone help me out here?
Yes, Airbus overstates the 350's range in its brochure. I have already shown exactly how and by how much. Their brochure range is THEIR OWN CABIN SPEC, do you get that!??!? However, no airline flies a cabin spec even close to theirs. Boeing decided to revise its brochure numbers downward to reflect more realistic numbers.
Surely airlines don't rely on brochure specs alone before they commit to spending billions of dollars on aircraft which have to last for 20 years or more?
I was under the impression that airlines use their own engineers and consultants to crunch the numbers? And surely they would have had access to the flight test data and real world data from other customers?
of course they don't depend on brochure numbers, but every single airbus fan on Anet does and for them, EVERY variant of the a350 inherits the 280t's attributes! On the DL/BOM thread, someone claims DL can just use "the 350" on ATL-BOM. It's absurd. Only the 280t variant has that kind of range. DL has none of those. JFK-MNL is a 278t...Air Phil didn't order this variant for kicks and giggles instead of a 276 or 268 both of which would've been cheaper. Right here is your "real world" range data.
Airlines negotiate performance guarantees with the manufacturers.