B787-800 for interest

[enicalyth]

http://www.lissys.demon.co.uk/samp1/index.html

By Dr Dimitri Simos who was remarkably prescient about the A300 and the B777.

Not an official Company "B" site but the worked of a skilled and intelligent man.

["....you can make one better, all I am saying is that it is highly inconceivable that my fiercest competitor will make one worse"... quote by Richard Shevell].

[Thunderball 2]

What an awesome piece of software....didn't even know it existed.

So Boeing are talking about an empty weight that is 15% below the figure that Piano predicts? As the good Doctor says, "a challenging task", but surely the Piano predictions would make the B787 heavier than the A350....or will Piano make the same over-weight prediction for that?!

:ok:

[BEagle]

Interesting how the 7E7 3-view looks nothing like the PR cr@p pushed out by Boeing......

[enicalyth]

G'Day Tee-Ball 2, G'Day Beags!

As it stands the version of Piano you see will overestimate the A350 similarly. The "Good Doctor" as you put it has to put food on the table. Even so what you see on the site as an appetiser would probably cost you the thick end of £20k GBP if you commissioned it as a one off study. As he sells his product and services to both Companies "A" and "B" he has to be careful. Each company knowing what it knows about its own research and what the proven weaknesses are in the opposition they undoubtedly use Piano as one tool among others, suitably tuned in-house, to keep a weather eye on the other guy. Sadly we only see the Demo version as it were.


However I'm still enjoying the Dim's outpourings on his revamped site. Shame he excised the A300 and B777-200ER from his "freebies" or should I say lucky I downloaded them first while they were available! Interesting are his Cdc and Cdtrim figures for the 787. My computer predictions deviate from his but the sum of the two is much the same. Always eager to learn.

We have yet to hear a lot about the A350 but the A330 (better suited to M0.82 cruise than 0.85 by a long chalk) has AR 9.3 (excl winglets), root t/c 15.25%, Inner kink 11.27%, Outer kink 9.86%, tip 10.6%, 3892sq ft and 30* sweep. (Airbus figures). Dim's publishing of the Boeing figures shows the merit of thinness and a little more sweep but the admonition is to keep the weight down or there will be more than tears. Please not another double kink or dogtooth to a prematurely frozen design.

Interesting also to see wetted and wing areas, my estimates not Dim's or company ones. Metric in sq m.

Wetted / Wing
A300-600R 1529.5 260
A330-200 1889.6 361.6
A330-300 1967.9 361.6
B777-200ER 2246.3 427.8
B787-800 1826.4 362.3

Quite a departure from the B777. Gawd have Boeing shaved that wing (and the elevator) but according to Dim the wing loading is already 133lbf/sq ft for the -800. Of course his structural weight is 15% higher not being as au fait with composites - at least in his demo sample. If Boeing is wildly wrong the wing has not much in hand for stretched versions.

Airbus are good at making a virtue out of a vice, always have been, yet they must surely have to go for thinner airfoil sections and two degrees or so more of sweep. Are they sticking with the legacy 5.64m fuselage dia? The 777 is 6.4, 787 a bit eggy shaped.

I think of my Dad who worked for de Havilland, Douglas and Airbus. It's 20 years since he took to pipe and slippers but I don't think he'd be floundering with today's technology. He prophesied trench warfare with every gain at enormous cost. Holden v Ford? Holdens ARE Fords.

I must get out more often.

Cheers m'dears

the "E"