Flying-V flying wing airliner

There is a simple solution to windows on the leading edge. Just get rid of them... and replace them with TV screens. Simplifies the structure and most people shut their windows down anyways.

Not me. Whenever I went on holiday abroad I always wanted the window's open to look out even if there was nothing to lookout at over the Atlantic Ocean.

This. Though I admit it would be cool if the plane had cameras around the exterior piped into an Occulus. (Like an F-35s display.)
 
Hi,

I discovered this concept before from NASA report,and here is anther one but for future.

 

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BWB meets Barnes-Wallis's Swallow.

On practical grounds, what's effectively a two fuselage configuration is unlikely to be popular with the airlines, and potentially with the regulators. For airlines it introduces the not-inconsiderable problem of directing boarding passengers into the right set of seats, likely extending turn-around times, and you potentially need additional flight crews, galleys and toilets vs a conventional fuselage design of similar capacity. For regulators, the problem is going to be escape capacity, with all passengers aft of the divide into two wings only being able to escape from one side of the aircraft. And as one side of the aircraft is often infeasible for escape due to fire, that's a problem. The evacuation scenarios are almost certainly worse in every blocked exit case than for a conventional fuselage aircraft.
 
With this arrangement, bird strike will be a show stopper;- a conventional cockpit window glass is about 40-50mm thick laminated glass and it together with the frame is very heavy but there’s only a few of them. Normal pax windows are only 6-8mm thick lightweight plexiglass but can’t be impacted by a bird. With a conventional wing the leading structure, a bird will penetrate the leading edge but loose sufficient energy that its remains won’t penetrate the forward spar which is the fuel tank boundary.

With this Vee wing thingy every leading edge window/frame will have to be strong enough to take a bird without rupture or discharge of debris afterward;- all the front aspect pressurised hull will have to take a bird without breach;- doors, especially emergency exits will have to take a bird without loss of function. Hence any aero benefit will rapidly be negated by the extra structural weight. Good luck with that.
You brought up a very important issue, that I have never seen before when reading about any flying wing transport. Maybe the only solution is to replace the passenger windows by TV screens, to show the outside world. On the other hand, I think safety regulation demand windows to provide lighting in an emergency. On the other hand again, the sweep-back of the leading edge will reduce the impact of the bird and the structure & windows may not have to be so strong.
in any case - an important issue for designers.
 
Maybe flying wings of all configurations will only be good for cargo, but the will have to have exeptional performance to be developed only for cargo.
 
Likewise, being in an aircraft and not being able to see outside is a waste. It has been a long time since I flew anywhere though (1995).

Times have changed. Nowadays, most airline - and bus - passengers spend their entire trip nose-down in their cell phones. They close window blinds to reduce distractions.
Hah!
Hah!

At most traffic lights in Vancouver, you will see at least one driver playing with his/her cell phone while waiting for the traffic light to change colour. Police get upset about that practice, but civilian drivers still find their cell phones more interesting than street traffic.
Hah!
Hah!
 
engines mounted above, is said in technical reports to benfit more on the laminar flow lift effect.
 
Some interesting tech info on the Delft web site now, including a general description and a FAQ:
https://www.tudelft.nl/en/ae/flying-v/technology
https://www.tudelft.nl/en/ae/flying-v/technology/frequently-asked-questions

Points relating to this discussion to date (some which I have come across elsewhere):

Engine location is highly sensitive to the local aerodynamics and will be refined as the design shapes up. Vortices at high AoA are the main worry. No mention of location under the leading edge, it seems to have been decided on for noise reasons, by the time anybody began serious study. Seems to me that the stalky u/c would allow such a position, which would resolve any stall worries, as well as the FAA's concerns over crashability.

Talking of which, the stalks allow a high AoA on takeoff and landing. This is done in conjunction with large wing area, so that no flaps or other high-lift devices are necessary.

I have seen BWB reports which claim that underslung engines would be a worse option because they require longer, heavier u/c when the designers are assuming nice stubby legs in their design study. I have seen no authoritative analysis to support the claim that rear-mounted engines, complete with heavy structural reinforcements to protect the cabin beneath (this last not mentioned in the published puff), are actually a better bet.

Most BWB designs have a less practical cabin. The big central space makes pressurisation a problem. Elsewhere I have seen criticism that in say an undercarriage collapse scenario with floor doors blocked, emergency evacuation would take too long. The reverse is true of the Flying-V. Boarding/exit times are likely to be better even than a conventional toothpaste tube. I suspect that this is mainly due to the big gaps in door spacing enforced by the usual wing root position; Flying-V can distribute them more effectively than usual, BWB has a real problem.

Blohm & Voss trialled extreme pilot positions on the wing tip in WWII. They found no issues with banking. This non-issue was confirmed by NACA/NASA after the war had ended. Flying-V passengers are not going to mind, half the time not even notice.

Delft reckon that the angled windows can actually be made larger than usual, due to the leading-edge radius. One hopes they have thought about bird strike, but they make no mention. A strike along the wing would be a glancing blow, not head-on, so I would assume that precautions can be watered down accordingly.

It's all still relatively early days yet, and several of these issues are still being thrashed out. Airbus are strongly interested, but not yet confident enough to push the Go button.
 
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Wasn’t there a three core EELV type fly back that would glide back that looked similar? The outer two strap-one with rogallo webbing connected to the center core?
 
Wasn’t there a three core EELV type fly back that would glide back that looked similar? The outer two strap-one with rogallo webbing connected to the center core?

Yes, it was Rogallo's first recorded use of the flexible biconical delta wing, which had first been developed for kites by people such as Bach and Wanner. The rigid biconical delta goes back to JW Dunne in 1904 and Lee & Darrah ca. 1910. Rogallo patented a triplet of side-by-side rockets hinged together at the front and with collapsible webs between them, so they would open out into a huge biconical delta for descent and landing. Aerodynamically it was a delta wing, not a vee.

Having said that, adapting the flying-V form to a re-entry lander is an obvious game to play. Cross-section at launch would approximate to a yin-yang symbol - two bluntly streamlined blobs packed into a single cylinder.
 
I guess, the bird strike problems could be solved, but de-icing is also an issue. Conventional de-icing with bleed air seems to be unpractical, but electric heating might work. Electrically heated windows or wingtips are nothing totally new, but I will surly takes a long time until all those issues are solved and certified.
 

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