The problem was once explained to me by someone smarter than I as follows:
Engineering is hard, marketing is easier, and more graduates are choosing the easier path. Thus to keep themselves employed the marketeers are stealing the design function from the engineers... but there's slightly more to it than drawing pretty pictures and imaginary budgets. Further proof of this is the recent spate of electric drone shuttles that have been "designed" by marketeers but can barely get themselves off the ground. But lets say for a moment that they pulled this off, the wing flex would be pretty awful on pax, and if they made it fully rigid then those air bumps might turn the interior into a flying circus of its own. |
DAR , lets embrace the Young and the idea. I was contracted to undertake certification planning for an STC'd modification to make a C 172 electric powered. The present design requirements do not enable this from a regulatory perspective, but only 'cause at the time the present design requirements were developed, there was no need to consider this. Now, there very certainly is, and I found the regulatory not only willing, but eager to undertake the development of new design requirements to enable electric aircraft. That happening is a certainty. However, the new design requirements will have to have the present ones as a starting point. Where a design cannon meet just one or two design requirements, it is common for a documented "Special condition" to be agreed upon between the design organization and regulator. That means that everyone has agreed that there's a different way, and allowed the design to proceed with that design. So perhaps the innovative team at Delft have recognized the gaps between their design, and the prevailing design requirements - I hope so, that's a part of any design undertaking. If so, they have prepared a "compliance table" listing the prevailing design requirements, and either how compliance will be shown, or where there is a gap which will require a change to a design requirement. This design appears so innovative, that a whole bunch of special conditions will not be enough. New design requirements will be required, and that is an early and extensive step in such a project. Perhaps that has been addressed in the description of the aircraft, if so, well done. If not, an instructor/mentor to the team has overlooked an important step, and the project has passed itself a little too much.... Out of a curiosity, can you transport legally pax in a cargo aircraft (one with no windows at all ) |
Well, it's not like any of this is new. Here's a 1971 NASA paper on lifting bodies.
https://ntrs.nasa.gov/archive/nasa/c...9710009392.pdf |
Originally Posted by Loose rivets
(Post 10485817)
So we sit next to the fuel? |
Originally Posted by Gove N.T.
(Post 10486054)
its a student exercise in engineering and, strangely enough, some students are pretty bright. |
Originally Posted by Flap40
(Post 10486518)
No one complained about the location of the tanks in the Shorts 330 & 360.
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Fuel in the wings isn’t ideal either. The Superjet fire at SVO proves the point. The theater seating is probably the breaking point. Pax just love the narrow tube.. |
V-Shaped Airliner
Can someone decode this statement
"The Flying-V will ultimately be propelled by turbofan engines but is currently designed to fly on kerosene fuel" V-Shaped Airliner |
There is no decode as it is simple PR.
As part of a suite of 'strategy' ICAO/IATA pump the technically feasible as solutions to aviation's continued reliance on fossil fuel. A flying V sounds great, has great images and laminar flow is assured, however it is practically a long way from a commercially viable vehicle. As is bio-fuel, technically feasible but commercially a long way from anything. So expect to see conventional wings and air frames at airports world wide for decades, all burning the same jet kerosene fuel of today. Of course a flying V might need a whole new lot of airport infrastructure world wide to accommodate it, but it sure is pretty... |
I can not find it again now, but I seem to recall one of the current articles mentioning the "petrol tanks".
I took note at the time and just put it down to journalistic incompetence. Maybe, just maybe, they are going to run this prototype on other than Avtur. |
Originally Posted by Pilot DAR
(Post 10486235)
I have approved ex freighter Cessna Caravans (no cabin windows) to carry parachutists. This was accepted by the authority, though with a sidewards glance (pun intended). I'm not aware of a design requirement stating that there must be windows for passengers to look out, but I think it's fairly widely agreed that passengers might not like the ride, if seeing out is impossible.
Where that gets dicey, is an in-flight or landing emergency situation, where the displays go dark and the pax are in a sealed cabin with no external view for anyone to know what's happening. Recipe for panic. |
I've posted this before, but new design concepts are a dime a dozen. Boeing has often played with a blended wing/body concept - apparently there is a pretty good drag carrot there if you can make it work - but even Boeing says if it ever happens, it'll probably start out as a military aircraft because it'll cost so that to do it commercially first would be corporate suicide if it goes badly.
Forty plus years ago I took a class on aircraft design in college (fun class - our prof literally wrote the book). You had to design an aircraft from scratch - and your final grade was determined by the quality (and documentation) of your design. Several of the people in the class initially tried to do 'revolutionary' designs (one was a vertical takeoff 'flying car', another a hydrogen fueled aircraft carrying fuel in the wings) - only to quickly discover that there is a pretty good reason why successful aircraft designs tend to look more or less the same. |
Originally Posted by 601
(Post 10487387)
Can someone decode this statement
"The Flying-V will ultimately be propelled by turbofan engines but is currently designed to fly on kerosene fuel" V-Shaped Airliner The journo has simply left out the electric reference, rendering the statement meaningless. |
apparently there is a pretty good drag carrot there if you can make it work But I'm sure the marketeers now running the design department will simply bolt a big emergency parachute to it, and the remaining engineer will devise a brick quick release system for guidance. |
it needs a ridiculous amount of speed (190Kts) to glide (at roughly 45 degrees nose down) The fact that a military or experimental aircraft can accomplish a maneuver does not mean that it's certifiable for civil applications. I believe that it's still a requirement for an airliner to be able to fly a glide approach to landing with average pilot skill. Yes, the space shuttle glides to land, but is the pilot skill "average"? I'm not a naysayer to advancement, but the aviation industry has a huge investment in the present design standards, so we must either follow them, or devote the effort to develop new ones... |
Good luck de-icing those leading edges.
No need? Think the moisture in the air will be so scared that it will refuse the freeze? De-icing is gonna require some doing. (And there is a LOT of surface for the ice to stick on. ) |
Presumably instead of conventional landing gear, it will have tele-castors.
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the Mirage fighter jet's delta wing whilst very efficient at high speed generates enormous drag at low speeds, should the donk(s) stop then it needs a ridiculous amount of speed (190Kts) to glide (at roughly 45 degrees nose down). There was even an old joke that developed which recommended that if the engine stopped then open the canopy, throw out a brick and follow it down |
John Farley told me that he dead sticked a Hawker Harrier at Edwards Airforce Base. He said the gliding approach speed was about 250 knots, but otherwise it was not difficult! I just keep thinking about those itty bitty wingtip wheels touching the runway at speeds like that!
The fact that a Mirage, Harrier, the Space Shuttle, or a lifting body can fly a gliding landing at high speeds and descent rates does not mean its certifiable that way in a civil aircraft! Hmmm, I wonder how the Concorde glided, I presume it had to for certification.... |
Speaking as SLF, I'm not sure I'd like to ride in one of the outboard seats. The vertical motion as the plane banks is going to resemble a roller-coaster ride.
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