Questions tagged [experimental-aircraft]
For questions about experimental aircraft that have not been granted a type certificate by a regulatory agency.
88
questions
35
votes
1answer
5k views
What is this 3-engine beast?
What is this 3-engine beast? It has an unusual 6-bladed propeller as well.
9
votes
1answer
282 views
What does it mean exactly when an aircraft is "35% unstable"? (aircraft stability factor)
CNN's Grumman X-29: The impossible fighter jet with inverted wings contains several interesting photos, and says:
It was unflyable -- literally -- without a digital flight computer on board, which ...
1
vote
2answers
223 views
What are the effects of placing the vertical stabilizer at the front of the aircraft? [duplicate]
I am experimenting with different aircraft designs. The one I am trying right now is a canard (horizontal stabilizer at the front) and the main wings are quite far back. I wondered if it would be of ...
3
votes
1answer
209 views
Does/did Russia or the Soviet Union ever fly rocket planes?
Did Russia or the Soviet Union ever have their own experimental or military rocket planes (other than the Buran), or did their military merely use jets and other non-rocket aircraft? America flew ...
5
votes
3answers
215 views
Can air-to-air refueling be done in compliance with the FAR's?
I am wondering if any FAR's would prohibit the air-to-air refueling of two civilian aircraft in the US. In our use case, the receiving aircraft would be custom-built, and it would receive fuel pumped ...
2
votes
1answer
181 views
How are composite aircraft canopies constructed that sit flush with the fuselage?
More specifically, how is the composite frame of the canopy manufactured? Attached picture as an example.
2
votes
1answer
218 views
Does anyone know more about the 1958 Heinkel-211 project?
Industria Aeronáutica Argentina worked in the 50s in a Jet airliner, Kurt Tank design, the IA-36, 'Cóndor', with simmilarities to 1958 Heinkel-211 project, turbines intake aspirating fuselage boundary ...
1
vote
1answer
298 views
What about a Plane-Train?
The Shanghai Maglev Train's max speed is 267 mph. Could a plane be made to follow a rail, surface area provided, if not an existing rail to travel along? How much faster could the heavily modified ...
2
votes
1answer
161 views
Could a wing be designed to exploit both normal flying and ground effect?
Ground Effect planes' wings are stubby and the height over the ground or water is limited to wing span.
Could a wing be designed to exploit both normal flying and ground effect together to give the ...
3
votes
3answers
519 views
Is it feasible to replace a C152's engine with multiple small turbine engines?
If I wanted to remove the piston engine from a cheap plane like a Cessna 152 and add small turbine engines with an equivalent thrust but weighing less, where would be the best place structurally to ...
1
vote
1answer
290 views
Any idea what this Ampaire plane is?
(Source)
This is certainly not the Ampaire 337 or Electric EEL, which is a converted Cessna 337. It looks like a boundary layer ingestor. Being from Ampaire, it probably is electric or hybrid.
I've ...
1
vote
0answers
39 views
How is NASA going to get high fuel economy on the X-57? [duplicate]
This X-plane is meant to fly soon.
It's a modified Tecnam.
The propeller direct wash over the wings, increasing lift. This allows the use of a smaller, high-aspect ratio, low drag wing.
But this isn'...
1
vote
3answers
495 views
The NASA X-57 uses 12 electric motors for takeoff. Does it need 12 control levers or just one?
If the NASA X-57 uses 12 motors for takeoff, does it need 12 controllers (like throttle levers), or just one?
The traditional way of engine throttle design was 1 throttle per engine, but what if you ...
20
votes
1answer
4k views
What is the asymmetric feature on the rear of a Sukhoi Su-47?
I saw this part on the rear of the Sukhoi Su-47 Berkut, and I can see that it is asymmetric. Is it maybe for interference, or is it a take-off aid because the Su-47 is a STOL plane?
What is it and ...
2
votes
3answers
1k views
What are the disadvantages of a Tail providing lift? (tandem-wings included)
Most aircraft feature the tailplane configuration, which requires the main wing to provide higher lift than the weight of the plane itself, what seems counterproductive.
Few aircraft have featured ...
1
vote
1answer
246 views
Are there any NACA airfoils that resemble the X-29's wing?
As a part of my project, I am trying to perform structural and aerodynamic analysis of a forward swept wing on an aircraft, specifically the Grumman X-29 (pictured below).
I am assuming that ...
4
votes
1answer
346 views
Would "Mad" Mike Hughes' steam-powered rocket have been certified airworthy by the FAA?
Daredevil 'Mad' Mike Hughes died after his homemade rocket crashed on 22 February 2020. The cause appears to be the premature deployment of the parachute used for a safe return. He was hoping to reach ...
32
votes
5answers
10k views
Why Didn't the USSR Build An X-15?
In the history of aerospace engineering in the United States, the X-15 is lauded as a critical and necessary step on the path to manned spaceflight. Throttle-able chemical rocket propulsion systems, ...
0
votes
0answers
171 views
Does a 3-blade prop handle up/down drafts better than a 2-blade?
I'm about to order a plane kit (RV-10) and one of the choices I'll be making is a 3-blade vs 2-blade propeller. A 3-blade prop should be: easier to balance, quieter and capable of generating more ...
1
vote
0answers
137 views
Can an aircraft be issued a standard airworthiness certificate after being operated under and experimental certificate?
14 CFR, §21.191 (b) states that experimental airworthiness certificates can be used when:
Showing compliance with regulations. Conducting flight tests and other operations to show compliance with ...
3
votes
0answers
103 views
What were the typical rotation and landing speeds of the X-29?
Looking online through all the available literature, I could not find the typical rotation ($V_r$), landing or even stall speed of the experimental forward swept wing X-29 aircraft.
I'm curious to ...
4
votes
1answer
511 views
Are there experimental aircraft regulations in Germany?
The title is the question.
Are there any special regulations regarding experimental aircraft in Germany (or the EU)?
Those "special regulations" would (hopefully) be looser set of regulations in ...
1
vote
3answers
419 views
Can a gas turbine be able to switch from torque to thrust?
Can a turbine engine be switched from providing torque (like a helicopter) to the rotor to transfer power to provide exhaust thrust (like a jet plane)?
Related: BV-347 upgrade this way?
-1
votes
2answers
634 views
Could a BV-347 be upgraded by extending the wings?
The CH-47 Model 347, also referenced as BV-347, was a helicopter that utilized a wing for forward flight and to carry external payloads. Could the wings be extended and engines on the rear rotor ...
10
votes
1answer
3k views
What kind of Chinook helicopter/airplane hybrid is this?
I had this question: Could this helicopter's body be a flying wing? and this picture came up.
What kind of helicopter is this?
What is the extra wing for?
9
votes
1answer
5k views
Why did the AvroCar fail to fly above 3 feet?
I don’t quite understand why the AvroCar didn’t reach more than 3 feet? Was it a ground effect keeping it at that height and it didn’t have the capability to fly higher?
2
votes
1answer
527 views
Could this helicopter's body be a flying wing?
This question: Could a helicopter fly like a plane this way? asks if a helicopter can turn sideways using additional wings to tip forward to allow the rotor blades to act as a propeller. The tail-...
-2
votes
2answers
145 views
Would a long pole help stablize a jet pack?
Jet packs are classically worn like a book-bag on the back. Would it be more stable if the exhaust ports were separated? Would the jet pack be easier to control if the turbines were at the ends of a ...
0
votes
5answers
659 views
Could a helicopter fly like a plane this way?
Could a wing be added to a helicopter to allow the entire craft to tip 90 degrees forward allowing it to fly faster like a plane using a fixed wing and leaning into the wing for lift?
I understand ...
5
votes
2answers
415 views
Has a small airplane ever been air launched from a heavy-lift helicopter?
I would like to know if a small airplane, like a Cessna, has ever been air launched from a heavy-lift helicopter, perhaps as a stunt or as an aviation experiment?
I think it would have been a simple ...
1
vote
1answer
162 views
What rotors would be best for atmospheric reentry?
What rotor blade set up would be the best for entering Earth atmosphere or to shed speed before landing in place of a parachute?
I understand that the longer blades are more efficient, but are not as ...
8
votes
1answer
408 views
How are businesses able to use experimental aircraft?
I saw businesses like this using military jets to sell rides to civilians. Since warbirds are considered experimental aircraft, does the FAA issue special certs to fly them commercially?
According ...
3
votes
2answers
123 views
Where can you find wind tunnel visualization data online?
I was wondering if there was a repository of flow visualization results somewhere online, preferably of wing sections categorised in some manner.
2
votes
1answer
374 views
Has the FAA ever granted a LODA for compensated instruction in a non-LSA E-AB?
I have been trying to find a list of granted LODAs to get this question answered. No joy. I am considering purchasing a Sling TSI E-AB. It would be great to be able to instruct in it for compensation.
8
votes
3answers
3k 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 ...
2
votes
3answers
900 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
596 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
253 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
864 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
344 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
2k 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
158 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 ...
1
vote
2answers
1k 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
200 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 ...
5
votes
1answer
665 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 ...
3
votes
1answer
2k 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
1k 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 ...
-1
votes
4answers
719 views
Spinning wing heat dispersion dynamics for Mach 24 and beyond?
Could a spinning disk dropped from orbit survive speeds faster than conventional aircraft in our atmosphere? Does the rate of spin matter when dispersing heat? Does a spinning disk create stability ...
22
votes
1answer
2k 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 ...
10
votes
3answers
908 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.
...
