Can thrust vectoring enable use of flaps on pure delta wing?

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Thomas Marks

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So I generally caution against such schemes, that introduce both otherwise useless weigh"
Batteries are heavy (no ballast required), have much higher density than fuel (less movement), does not change weight being depleted (no trim movement), can be fixed easy and reliably (mechanical pin) and will be moved only twice per flight short after / before landing (can be mechanically mixed with flaps control for take-off speed). And even if jammed at take-off pilot can go around and land back, and if at landing - do a higher speed run if possible or go to another spot.
 
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Thomas Marks

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When the big military fly by wire projects have a glitch, the pilot often manages to eject. The plane is always a smoking hole in the ground. Maybe you can do as well as gigabuck funded teams of experienced engineers,
I understand your reasoning, but it sounds kind of dated.
There are more than a hundred eVTOL startups https://evtol.news/vectored-thrust, some of them are already delivering and not a single one without computer in the loop.
 

TFF

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Startup is one thing. Media darling does not mean products in hand.
The FAA is slow to react because they did not see this coming, but if the FAA reacts like they always do, these types of aircraft will be classified as Powered Lift. It’s a pilot license class, but there is no way to get one this side of being a civilian Osprey test pilot. Right now, no one has been hurt that we know about. Rules get written when people do. You might be in a location where no one is looking, but most other countries copy the FAA rules and add their own twist. Can’t hide behind, others are doing it. If you design something that will get regulated, you better develop a training program on how to operate. Hovering around in your back yard is completely different than flying across town.
 

Thomas Marks

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Prague, CZ
Since I asked this question, I have been reading the HBA forum backwards and forwards and found almost all my ideas at least mentioned, while many - discussed in all possible perspectives.
Nevertheless, you all, replied to my thread. I appreciate it very much, this is the most welcoming online community I have ever joined.
Thank you.
 

Swampyankee

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On a swept-back flying wing, one could put trailing edge flaps near the c/g and still generate enough pitching moment from elevons located near the tips, far behind the c/g, and still get a net increase in coefficient of lift. You could also use leading edge flaps, which would require a greater angle of attack, but would have relatively small affect on the wing's pitching moment. It would be a balancing act of the sort that's kept flying wings from being considered viable for anything but a few edge cases. A tailless delta, which is really just a low-aspect ratio flying wing, has the same sorts of issues. For a STOL-aircraft, a delta would be close to my last choice (somewhere ahead of arrow wing, lifting body, and hypersonic waverider). A good place to see how deltas suck is the comparison with the Mirage F1 (swept wing) and Mirage III (delta). The F1 needs a shorter runway and has longer range, better transonic maneuverability, and greater payload than the Mirage III.

Combining high cruise efficiency and STOL in the same aircraft is complex, but one should note that the aircraft that combine the two tend to have moderate to high aspect ratio wings and conventional wing-first design. A three-surface aircraft may do better, but they're not simple (they're not called the welfare program for aerodynamicists for nothing). Thrust vectoring is used on a couple of military aircraft, but it certainly adds complication and weight.
 
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