If you’re interested in this sort of stuff, this is the best book I’ve found on the subject, it is very practical and written with the engineering minded amateur designer in mind: https://www.amazon.com/Design-Aeroplane-2e-Darrol-Stinton-dp...
Here's a concept from Elytron: https://rotorcraft.arc.nasa.gov/Publications/files/Grima_The...
The advantage is lower induced drag during cruise. You do analysis to validate controllability during high-AoA regimes. As with every design choice in aviation, it's a tradeoff.
Losing lift on that rear wing, which there is a massive range of opportunity to do, will yank the rug out from under the back of that aircraft. How often will this design suddenly decide to fly tail-first tens of feet away from touching down on the tires?
t tails on most business jets etc.
A major exception is aircraft with an inverted V tail, like the Lazair ultralight and the MQ-1 Predator drone.
Another exception is the flying wing, like the B-2 Spirit, but that certainly isn't an aerodynamically low-risk design.
Another exception is weight-shift ultralights that look like tricycles hanging under flying wings.
From the linked article: "This [crashed] aircraft was intended to be the production version of the "Stratos" aircraft. The prototype version had successfully flown some 340 hours. The production model incorporated significant changes made by the designer/pilot."
Test-flying unconventional prototype / experimental airplanes, or flying commercially available ultralights? With or without training?
And wingsuits – proximity flying? base jumping? Or just jumping out of a plane?
The risks of those scenarios are magnitudes apart.
Personal aircraft are about as dangerous as motorbikes. Base jumping on the other hand, whether with a wingsuit or not, is one of the most dangerous recreational activities you can do, with a fatality rate of something like 1% per participant per year.
If anyone wants a crashed belite in the PNW area, let me know.
I managed to advance to an unpowered glider, but without
a motor, and no chance to get a tow from anybody.
I managed to take off once, for a few meters from a slope, and that was it.
Once I hit 16, I had to leave Russia, and the unpowered glider parts still lie in my uncle's garage.
On the flipside, though, stalling a Ligeti Stratos is probably a major event since it's almost a flying-wing.
In fact, all planes can gain altitude without pitching up, by increasing speed, and by decreasing speed can lower altitude. The resulting lifting force on the wings is for most important flight regimes a function of speed and angle of attack.
I assume that AoA=0 and flat wing (not a teardrop-shaped one) would not lift off despite increasing the engine power (assuming no wind). Is that correct?
I'm very much confused by what you're saying - given that "lifting force on the wings is for most important flight regimes a function of speed and angle of attack", isn't it easier to change the AoA, by operating the control surfaces and pitching the plane, instead of adding or reducing speed?
Consider taking off in a taildragger. You start the takeoff roll with the tail on the ground, giving an angle of attack close to that of a stall, but at some point before lifting off, you typically raise the tail, because you do not want to stagger into the air on the point of stalling.
If you are flying level at a constant speed, and then raise the nose without changing the power, you will initially rise, but you have tilted the lift vector backwards, increasing its backwards component, so your thrust is no longer sufficient to maintain speed (it is the same as a car going from flat to uphill.) If you are on the back of the drag curve (where drag increases as you slow down), raising the nose can result in going into a descent.
An aircraft in a straight steady climb weighs no more than when it is flying straight and level, but there are two factors to consider. Firstly, the angle of attack is relative to your trajectory, which is now tilted. Secondly, on account of that, the lift is now tilted back, so the wing must create more lift in order that its vertical component is equal to the weight. Therefore, the angle of attack itself needs to be increased (and even more if your climbing airspeed is going to be lower that the speed you were cruising at.)
Putting it together: to go into a climb, you must increase your thrust (or 'get some back' by allowing the aircraft to slow down to reduce the drag, but that's not an option when you are going slowly.) Secondly, you must increase the angle of attack, but that happens as a consequence of adjusting the pitch of the aicraft to maintain the desired/correct speed.
You’re assuming a lot here. It basically comes down to lift coefficient of the wings when a certain power magnitude of air is forced under them. This comes from thrust. Power. You can climb with power being perfectly level. You should NOT increase your angle of attack (this will induce stall as it increases drag).
It’s weird, it’s backwards, but it’s physics. Pitching up increases drag and increases the angle of attack increasing your power requirements to stay at altitude.
This is a video I found on YouTube from my local college:
In aeronautical terms, Power as P comes from lift and drag, you assume it’s from the wings, when it’s the thrust from the engine providing the compressed airflow (because we’re going fast) under and over those wings.
I’ve been flying simulators and aircraft most my life as a hobby (due to slight red green colorblindness, I couldn’t be a fighter pilot so I went into computers). One thing I always have friends try is just keep the Cessna straight and level, increase power, she’ll lift on her own when she reaches that sweet spot.
Actually, I am not. I am assuming only that, for an unstalled wing and a fixed flap setting at a given air density, lift increases with airspeed and also with angle of attack, plus Newtonian mechanics. Nothing here is contradicted by the video you linked to.
> It basically comes down to lift coefficient of the wings when a certain power magnitude of air is forced under them.
This appears to be gibberish.
> Power as P comes from lift and drag, you assume it’s from the wings, when it’s the thrust from the engine providing the compressed airflow (because we’re going fast) under and over those wings.
> I’ve been flying simulators and aircraft most my life as a hobby.
Well, I fly airplanes too. This just goes to show that you don't need to understand the physics of flight in order to learn how to pilot an airplane.
Too little and you strike the prop.
The way you’re taught to land you use the controls is basically backwards - the elevators (pitch) control speed. The throttle controls rate of descent.
“During a short test flight of the new highly modified production version in September 1987 the airplane stalled during approach to landing and Charles Ligeti was killed.”
“During a short test flight of the new highly modified production version"
That’s not cleanly “exactly same” nor “totally different” airplane design, but the mishap airplane was clearly closer to this effort than to a 172.
It's a pretty thing for sure. And I think it's neat they want to give away plans. Just don't think it's a big impact.
Open source is about more than price.