Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

For questions about experimental aircraft that have not been granted a type certificate by a regulatory agency.

6
votes
1answer
211 views

Can an amateur-built aircraft ever be used for commercial activities?

There are some non-recreational activities, such as aerial photography, wildlife observation, environmental monitoring, etc., that seem well-suited to certain amateur-built aircraft. The open-cockpit ...
0
votes
2answers
202 views

Can a Rutan Quickie be made into a legal Part 103 Ultralight?

I was was thinking about buying a 80s rutan quickie q-1, it has a 18 hp motor. I want to get a ultralight but I like this one because it is fast. Can I get a motor that would be within the ...
0
votes
1answer
63 views

Why does the Aurora D8 have vents on the bottom of its fuselage?

The Aurora D8 is a concept of an experimental aircraft (not an actual aircraft for now), described in this site. It's discussed in this question here on Aviation.SX. I was watching the embedded video ...
0
votes
1answer
67 views

Airfoils designed for reverse flow [duplicate]

This question might seem strange as almost all aircraft have the air flowing over the wing in only one direction. However if you wanted to design an airfoil would have a good L/D in the forward flow ...
5
votes
2answers
230 views

How can someone without a pilot's license arrange an initial test flight for a homebuilt aircraft?

I think this has more to do with culture and expectations than actual rules, so maybe this might attract opinionated answers, but I still want to know what people think: If a person were to construct ...
2
votes
1answer
80 views

What are the FAA's requirements for an experimental type certificate?

What is required by the FAA to obtain an experimental type certificate for a manned prototype aircraft?
4
votes
1answer
302 views

Is it legal to rent out an experimental aircraft?

Is it legal to rent out an E-AB aircraft (not a light sport aircraft)? The aircraft will not be used for hire or compensation but to rent out to a pilot who wants to fly from point A to point B. ...
0
votes
0answers
79 views

Can you own a fractional portion of a kitplane or experimental airplane?

I understand that experimental/kit planes can't be used for 'training for hire', i.e. an option of leasing them to flight schools is out. But... is it possible to own such aircraft on the fractional ...
0
votes
2answers
308 views

Could a blimp maneuver using a sail? [closed]

How do you build a sail for a blimp/hybrid airship and what would it look like? Similar to a sail boat how could a blimp maneuver without propellers? Can a blimp sail against the wind? Wind can travel ...
0
votes
0answers
80 views

Will the Honda CG 125 engine be able to lift a 200kg weight at 2100 RPM? [duplicate]

I found a Rotex company engine with a maximum RPM of 5800. However, company allows 70% mean 4000 RPM, so I'm sure that 2100 RPM will be enough for lifting or take off and be able to climb. I have ...
3
votes
1answer
232 views

What would be the effect of skinning over the gap in fixed leading-edge slats?

The Zenith STOL CH-750 experimental aircraft uses a modified NACA 650-18 airfoil (having a 17% fatter-than-normal thickness) with a fixed leading-edge slat. In an effort to reduce drag and improve ...
2
votes
1answer
459 views

Can I do an instrument rating checkride in an experimental aircraft?

The EAA has a document that strongly suggests that IFR operation in Experimental Aircraft is legal. The necessary equipment is described in 91.205. Provided all this is met, as well as all other IFR ...
5
votes
3answers
353 views

What are the factors required to estimate the minimum required power for an experimental aircraft of a specific mass?

I have already viewed these questions: Basic aircraft performance: how can you calculate the required power? How can I estimate the required T/O power for propeller aircraft? But is there a ...
0
votes
0answers
39 views

Why don't we see more aircraft with a variable (swing) wing today? [duplicate]

During the Cold War, there was a great interest for variable geometry (swing) wings for military aircraft, e.g. between 1965 and 1975, Dassault designed 4 types of Mirage G which never went into ...
0
votes
3answers
483 views

Could a spinning disk disperse heat better?

Could a spinning disk dropped from orbit survive speeds faster than conventional aircraft in our atmosphere? How fast would the disk have to spin to keep it stable along with heat dispersion? Can it ...
21
votes
1answer
1k views

What was enabling control to the pilot on the Snecma C-450 Coléoptère?

Looking at the Snecma C-450 Coléoptère, I was wondering about the (4?) fins towards its tail: Source: Wikipedia Were they able to pivot to help the pilot control the aircraft? If not, what else ...
8
votes
3answers
593 views

Has anyone researched or built an aircraft that controls pitch and roll by pumping liquid within the airframe?

I am confident I have seen an article couple years ago about a "static surface aircraft" (or at least a concept of it) with no control surfaces, which uses a "wet mass" to adjust its roll and pitch. ...
1
vote
1answer
136 views

Are experimental aircraft exempted from the 2 year transponder and avionics checks?

Experimental aircraft and LAS. The 2 year verification test for avionics , transponder and altitude encoder. Are experimental aircraft exempted from this test or they must comply ?
6
votes
1answer
704 views

May I fly with passengers on a homebuilt experimental airplane with only a simple PPL?

So I’m in the market for a small two-seater. I see a lot of homebuilts and experimentals listed that are perfectly priced. I have my private pilot certificate but that’s it. Would I be able to fly ...
7
votes
1answer
471 views

What is this Lockheed Martin plane?

It's on a Lockheed Martin banner showcasing the company's iconic planes. The plane to the left on a crimson background is the U2, and the plane to the right on a blue & tan background is the C130. ...
5
votes
1answer
430 views

How come there is no attempt at an “inter-meshing rotorprop” high-speed helicopter?

There are some prototypes of high-speed helicopters, such as the Eurocopter X³ (X-Cubed), Sykorsky X2, and older ones such as the AH-56 Cheyenne. At high speeds, forward and backward traveling rotor ...
56
votes
2answers
8k views

What is this odd aircraft?

What is this aircraft? It was parked at transient parking at the Southern California Logistics Airport. It is a pusher prop driven plane with a conventional tail. High aspect ratio un-swept wings. ...
3
votes
2answers
661 views

If I were to scratch build a helicopter, as the manufacturer, would I need a pilot's license to fly it?

If I were to scratch build a helicopter, as the manufacturer, would I need a pilot's license to fly it while its in the experimental stage? This is in the USA, but I'd be interested in how it plays ...
5
votes
1answer
256 views

Which FAA regulations apply to the Stratolaunch?

(Image source) Which FAA regulations apply to the Stratolaunch being built by Vulcan Aerospace and Scaled Composites? Do they follow the same regulations for the type cert, production and CofA (...
6
votes
1answer
190 views

Can (part of) the fuel in your tanks be considered “property carried for compensation or hire”?

This question brings up that an experimental category aircraft cannot carry "persons or property for compensation or hire". However, this raises a question regarding civil-registry refueling tankers (...
2
votes
2answers
439 views

May a commercial pilot transport an owner in the latter’s experimental aircraft for compensation?

Say Olive Oyl owns an RV and wants to hire Popeye, a commercial pilot, to fly her to the beach in her aircraft, which has an experimental certificate. May Popeye legally accept compensation for this ...
1
vote
2answers
482 views

Could flywheel type gyros stablize a plane?

An aircraft carrier has massive spinning gyros to keep the ship upright against waves. Do planes of any type have gyros like those used in satellites? Not instrument gyros. In the picture below ...
-5
votes
2answers
569 views

Why are car engines not used for planes? [closed]

I found this picture of a 1/2 VW Bug pan air cooled engine in a plane. Source What other air cooled car engines work well in a plane?
3
votes
1answer
357 views

Why does the NASA GL-10 Greased Lightning run on diesel?

I've been reading about NASA's experimental GL-10 Greased Lightning tilt-wing aircraft with interest. My understanding is that this is a diesel-electric hybrid aircraft uses stored electrical energy ...
0
votes
4answers
693 views

What is a blimp called if it is designed not to be lighter than air?

I have not found a name for a this type of vessel what class a vessel is it? Could it operate similar to a parasail if dropped from a high altitude or orbit with air far thinner then operational ...
1
vote
0answers
156 views

Is it technically feasible to dampen the control stick in an Autogyro?

The control stick in a gyrocopter is too wobbly for a glider pilot's liking. Is there a way to dampen the stick in a Gyrocopter [Eg. the Air command] to make it feel as smooth and light as one would ...
2
votes
2answers
439 views

Could the vertical stabilizer be removed on the NASA X-57?

I was reading this article about how NASA will develop this new X-57 X-plane which has many tiny electric motors mounted on the wing. Now, I wonder: How come this aircraft still has a vertical ...
0
votes
1answer
357 views

What are the design goals for NASA's X-57? [duplicate]

There have obviously been work going on prior to the X-57 announcement (see LEAPTech and Joby Aviation http://www.jobyaviation.com/LEAPTech/). However, what does NASA actually think they will achieve ...
7
votes
1answer
1k views

Why do forward-swept winged fighters have the main wings in the back?

These are the only 2 fighter jets I know of with forward-swept wings. (Su-47 and X-29, they're both still experimental). As you can see, they both have their wings in the back, not the middle. Why is ...
1
vote
1answer
247 views

Where can I find a free/cheap small airplane wing?

I am looking for a small airplane wing (e.g. Cessna 172, but not necessarily) to run some experiments prior to seeking an STC for a modification I am working on. Do you know where I can find a free ...
7
votes
3answers
5k views

What is the procedure to turn a certified aircraft into an experimental aircraft?

Last year at EAA Airventure I saw a helicopter (can't remember the model, but it was something like a Eurocopter EC135 or similar with a full glass cockpit). It was US registered (N-Number tail) but ...
2
votes
2answers
495 views

What are some alternative benefits to electric propulsion?

The context I am asking is regarding if electric motors could ease the fuel cost, take off weight, or runway length if they were set up in 'hybrid' configuration with regular hydrocarbon engines. If ...
7
votes
2answers
493 views

How much could human power add to the endurance of an electric gyrocopter?

If we take a single seater electric gyrocopter like this one, could a human-powered propeller like this add to the endurance of the aircraft? The gyrocopter only needs a 32km/h forward speed to stay ...
5
votes
2answers
254 views

Can a gyro-copter soar?

If one centers the gyro-copter in a thermal and then simulates a hover facing headwind; can the gyro-copter climb up like that ? Is it technically possible or is it advisable....
45
votes
1answer
5k views

What is the purpose of the extra wheel on the XB-70 main gear?

This photo of the XB-70 Valkyrie's main gear shows a small wheel between the two main wheels: Courtsey of AirPigz.com This smaller wheel doesn't touch the ground, though I can see where it might as ...
25
votes
2answers
5k views

What is this red canister on the tail of the YF-22?

On the tail section of the YF-22 further back in the image below, there is a red canister. What is that canister for? I suppose it is for some flight testing purposes from what I can see. I can't ...
20
votes
1answer
1k views

What is the 'arm' at the rear of the X-29?

In this image of the Grumman X-29, there is an 'arm' just above the exhaust nozzle leading forward and, apparently, attached to the right side of the fuselage. What is this and what is it for? Source:...
3
votes
1answer
147 views

Can a kite take advantage of crosswinds to gain speed? [closed]

In a form off a kite can wind be redirected like a sail boat in any direction? Can cross winds around a jet stream be helpful in speed in such a design?
16
votes
1answer
628 views

How can the Perlan II glider climb to 90,000 feet?

I've been reading material about the Perlan II experimental glider. They hope to take it up to 90,000 feet -- higher even than an SR-71 BlackBird. But the Perlan II is just a glider. Can it really ...
7
votes
1answer
833 views

Why was the experimental MiG 1.44 so similar to the experimental TKF-90?

Why was the MiG 1.44 so similar to the MBB TKF-90? (for some information on the TKF-90 you have to scroll down this question, it is the only one source I knew about this particular plane) Here is the ...
7
votes
1answer
255 views

Is there a way for an ultralight or powered glider to smoothly enter a jet stream?

Once inside the jet stream altitude 7-15 km is it all that turbulent or is there a way to enter it smoothly for an ultralight plane or a powered glider? More info
9
votes
2answers
1k views

First to fly around the world by riding jet streams possible?

My questions are related to a scenario discussed on Earth Science: A huge (heavier-than-air) kite sailing in and out of the jet streams. The kite: The scenario: https://earth.nullschool.net/#...
17
votes
3answers
2k views

Was there any progress in ramjet-powered helicopters after 1960?

It seems in 1950's some countries investigated production of helicopters powered by ramjet engines on rotor tips - examples include American Hiller YH-32 Hornet or Polish JK-1 Trzmiel. The enthusiasm ...
-2
votes
1answer
821 views

Is the Boeing AC-25A Banshee a real concept or a gimmick? [closed]

Could this be a feasible concept aircraft to replace the AC-130?
9
votes
1answer
2k views

What does YF stand for?

I know that F=fighter, A=attack, F/A=fighter/attack, B=bomber. I can not find any information on what YF stands for. This type of aircraft is usually an experimental aircraft, but why do modern ...