Blackbird From , joined Dec 1969, posts, RR: Posted (8 years 2 weeks 1 day 3 hours ago) and read 1480 times:
I know a BWB has some issues in weight due to pressurization of a pressure-hull that is not cylindrical but heavily ovalized or even using a bunch of rectangular sections. I'm not sure if this is true, but have they figured out anyway to overcome some of these weight excesses?
I am curious because Boeing is developing it's X-48B design, and I'm wondering if they were able to overcome the strengthening problems. (Additionally, if applicable: does anybody have an estimate over how much heavier or lighter a BWB would be over a regular airliner if these new strengthening techniques were applied to the BWB's design?)
FredT From United Kingdom, joined Feb 2002, 2185 posts, RR: 26
Reply 1, posted (8 years 2 weeks 1 day 2 hours ago) and read 1467 times:
You can't really overcome it. It is a fact and you have to design for it. A pressure hull of any other shape than a sphere will mean a disadvantage compared with the spherical design case. Compromises, compromises. If you believe the benefits associated with a BWB design will outweight the weight/space penalties of having a non-round pressure hull or a round pressure hull built into a non-round fuselage, you design a BWB aircraft. If not, you stick with the traditional fuselage on a wing concept.
You need more structural strength. You can then beef up the structure, adding weight. To counter the weight increase, you can throw money at more complex materials, more complicated manufacturing etc etc.
I thought I was doing good trying to avoid those airport hotels... and look at me now.
Blackbird From , joined Dec 1969, posts, RR:
Reply 2, posted (8 years 2 weeks 19 hours ago) and read 1431 times:
How much weight would a two deck 800-pax, 160-foot length by 290 foot span, by 40 foot height BWB with a 37.5 to 38.5 degree wing-sweep with 21st century weight savings technology (including the use of this shear-thickening fluid which is like a liquid armor that can become hard as hell, bullet proof, knife proof that I mentioned in a previous link: http://www.weaponsblog.org/entry/she...-liquid-armor-to-protect-soldiers/ I posted) weigh in at... about? I just need a range of weight, an educated guess... hell even a basic guess