Oddball, Experimental, or One-off

[red750]

The Yokosuka R2Y Keiun (景雲 - "Cirrus Cloud") was a prototype reconnaissance aircraft built in Japan late in World War II.

 

Commissioned for the Imperial Japanese Navy after the R1Y design was cancelled due to its disappointing performance estimates, the R2Y used coupled engines driving a single propeller and also featured a tricycle undercarriage.

 

Completed in April 1945, the prototype made a short flight on 8 May, but was destroyed in a US air raid only a few days later, thus ending development.

 

[red750]

The Horton Wingless aircraft was invented by William Horton of Huntington Beach, California in 1952. He called the strange-looking plane “wingless” because he claimed the entire craft was a simple air foil with vertical fins and utilized all surfaces for lift. Unfortunately, Horton did not have the money to develop it, but was able to get into a partnership with billionaire Howard Hughes and Harlow Curtis.

 

The plane had a successful, but short, test flight. The venture failed not because the airplane didn't fly, but because Hughes wanted to take full credit for the patents and production rights, which Horton refused to allow. Hughes sued Horton which effectively stopped any further development of the aircraft.

 

Hughes managed to have the prototype and partially-constructed production version destroyed. One aspect of the law suit was a statement that the aircraft could not fly, which witnesses, photographs and video obviously show not to be true. At one point, Horton served jail time for selling stock in a company for an airplane that "couldn't fly" and had several violent confrontations with people associated with Hughes and Curtis because of the law suit and resulting injunctions." 

 

[red750]

The Grumman XP-50 was a land-based development of the shipboard XF5F-1 Skyrocket fighter, entered into a United States Army Air Corps (USAAC) contest for a twin-engine heavy interceptor aircraft. The USAAC placed an order for a prototype on 25 November 1939, designating it XP-50, but it lost the competition to the Lockheed XP-49.

 

[red750]

The Airbus RACER (Rapid and Cost-Effective Rotorcraft) is an experimental high-speed compound helicopter developed by Airbus Helicopters from the Eurocopter X³. Revealed at the June 2017 Paris air show, final assembly will start in mid-2020 for a 2021 first flight. Cruising up to 400 km/h (216 kn), it aims for a 25% cost reduction per distance over a conventional helicopter.

 

On 20 June 2017 at the Paris air show, Airbus Helicopters revealed a high-speed demonstrator configuration based on the X3 developed within the Clean Sky 2 research programme. Its aerodynamic configuration was validated in 2017. In February 2018, the 2,500 hp (1,900 kW) Safran Aneto-1X power plant was selected over the RTM322 initially selected, it is 25% more compact for the same power.

 

By October 2018, design of key subsystems was completed before the first components started manufacturing with long-lead items, as the lateral drive shaft production began. GE's Avio Aero in Italy launched procurement and manufacturing of the lateral gear boxes housings, GE Aviation Systems in UK is building the wing’s titanium cradle, INCAS/Romaero in Romania started the design and manufacturing the hybrid structure (metal & composite) of the Main Fuselage and the Firewalls and Aernnova in Spain the tail parts primary structure.

 

It made its first flight on 25 April 2024 in Marignane. By its third test flight in May, it had performed aggressive manoeuvres and reached 165 kn (305 km/h), using 300 kW (400 hp) less power than a conventional helicopter, while both engines were at 50% torque at 160 kn (300 km/h). It should reach 220 kn (410 km/h) later in 2024 and the “eco-mode” with one engine shut down in cruise should be flight tested in 2025, along mission demonstrations.

 

[IBob]

Looks like the one on the right is POC?
Then the LH one they've ditched the lower struts and gone from pusher to tractor.....

[Marty_d]

Interesting design.  Guessing that the lack of tail rotor is because the side motors are used to balance out rotational forces from the main rotor - in which case you could only ever stop one side motor (and the same side too).

 

[IBob]

I wonder what the drive mechanism is to those props???

[Marty_d]

3 minutes ago, IBob said:

I wonder what the drive mechanism is to those props???

"Lateral drive shaft" is mentioned.

 

[IBob]

You're right Marty. And gearboxes.
 

[onetrack]

More info in the links below. Looks like a typical, extremely complex, European design machine to me, complete with all the normal reliability problems that come with them.

 

In depth: Airbus’ Racer fast helicopter set for 2020 test flight

WWW.AEROSPACETESTINGINTERNATIONAL.COM

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With one year to go before its maiden flight, Airbus Helicopters' Racer technology demonstrator, which aims to reach speeds of up to 400km/h (250mph) is innovating in terms of its design and flight testing

 

Advanced Assembly Solutions for the Airbus RACER Joined-Wing Configuration - Mobility Engineering Technology

WWW.MOBILITYENGINEERINGTECH.COM

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The Rapid And Cost Effective Rotorcraft (RACER) demonstrator is being developed by Airbus Helicopters (AH) to further validate the compound rotorcraft configuration.

 

[BrendAn]

t

[BrendAn]

1 minute ago, BrendAn said:

t

similar concept to the rotordyne, whats old is new again. the rotordyne used jet powered rotor tips to hover and take off vertically, it was an autogyro.

Edited July 31 by BrendAn

[Red]

On 28/07/2024 at 11:24 PM, Marty_d said:

Interesting design.  Guessing that the lack of tail rotor is because the side motors are used to balance out rotational forces from the main rotor - in which case you could only ever stop one side motor (and the same side too).

 

Unless of course it had a reverse pitch function on the props as most Turboprops do for braking, then you could lose one side and still have control of Yaw

(Also I imagine both props could be powered by either engine...the whole drive system will likely be linked )

Edited July 31 by Red

[spacesailor]

Fairey Rotodyne .

There was no ' torque ' from those rotors .

As an " autogyro " it was able to ' glide ' to a safer landing than most aircraft of that time .

[red750]

The DuPont Aerospace DP-1 was a subscale prototype for a fixed-wing VSTOL transport aircraft, intended to take off and land like a helicopter and fly like an airplane. The fullscale aircraft, named DP-2, was designed to travel at high subsonic speeds with a greater range than its rotary-wing equivalent, and to allow troops to rappel from the aft cargo ramp. The development of the 53% scale DP-1 aircraft was originally funded in the early 1990s as a backup to the V-22 Osprey program, which was undergoing significant technical and political challenges. During the construction of the test aircraft, program management changed the requirements, and mandated that the vehicle be tested as a UAV. This change added significant cost and time to the project, but in September 2007, the DP-1 autonomous prototype achieved sustained, controlled tethered hovers of 45 seconds at the Gillespie Field test site.

 

On June 13, 2007, the U.S. House Committee on Science and Technology held a hearing about the fate of the DP-2. In August 2007, funding was finally cut, after a total of $63 million spent over nearly two decades.

 

[Red]

On 01/08/2024 at 2:10 AM, spacesailor said:

Fairey Rotodyne .

There was no ' torque ' from those rotors .

As an " autogyro " it was able to ' glide ' to a safer landing than most aircraft of that time .

Was referring to the airbus helicopter  Ss

[red750]

The RUMAS 10 is a strikingly designed light helicopter by the Czech-based RUMAS (Russian Ukraine Maslova) group.

 

The helicopter uses a three-bladed coaxial counter-rotating main rotor system along with a pusher-type tail rotor reminiscent of the Sikorsky S-97 Raider.

 

The 10 is intended primarily for civil use and takes the unmanned future of aviation into account with its design. Unlike most helicopter the 10 has a main rotor that is not tilted during flight, since propulsion is provided by the rear pusher-type propeller. This is a feature that significantly decreases drag. The rear propeller is a high-speed fully reversible unit that can quickly change its thrust vector to accelerate or brake the aircraft. The combination of these different design features results in a helicopter with a guaranteed cruise speed of 155 mph (250 kph) and a designed top speed of 186 mph (300 kph). This is a 75% improvement on the cruising speed of traditional light helicopters. A higher flight speed translates to lower per-hour flight costs, coupled with an asking price estimated at 850 000 USD the 10 becomes a very attractive prospect, as it is in the same price range as a Bell 206 Jet Ranger. An aircraft that tops out at 137 mph (222 kph).

 

Another interesting aspect of the 10 is the choice of power plant. One may have either a single gas turbine engine rated at 220 horsepower or two rotary piston engines for a similar combined rating. The relatively low absolute engine power makes the performance, and therefore aerodynamics, of the 10 all the more remarkable.

 

In terms of design the 10 certainly looks like a 21s century aircraft, with an aesthetic that is more reminiscent of Apple computers than Eastern European design bureaus such as Mil. This is clearly a result of RUMAS’ experience with modern composite materials. In fact, apart from engines and avionics, RUMAS manufactures everything in-house. The cockpit size and design also clearly have comfort in mind, which is another departure from historic vehicle design from this part of the world.

 

Where typical light helicopters assume a pilot weight of about 175 lb (80 kg) the 10 works on an assumption of 265 lb (120 kg). It will also accommodate pilots slightly taller than 6ft (about 190 cm).

 

The Russian and Chinese markets are likely to be the main recipients of 10s when they become available. The Russian market alone has an estimated demand of 30 units per year according to RUMAS. If the helicopter performs as promised at its proposed price it has a good chance at market success.

 

[red750]

Pitcairn PA-36
Developed in 1938, the PA-36 has an all metal fuselage and rear engine.  The front wheels are steerable.

 

Tabular details here,

 

[red750]

The Cierva W.11 Air Horse was a helicopter developed by the Cierva Autogiro Company in the United Kingdom during the mid-1940s. The largest helicopter in the world at the time of its debut, the Air Horse was unusual for using three rotors mounted on outriggers, and driven by a single engine mounted inside the fuselage.

 

Only two aircraft were built, further development by Cierva was stopped after the crash of the first one and little work was done under Saunders Roe before the project was ended and the second aircraft was scrapped in 1951.

 

 

[red750]

Cessna 407

The late 1950s and early ’60s saw a frenzy of aircraft development. Largely driven by military contracts that called for a specialized type dedicated to each role, variety abounded, and unique designs emerged to address the many military requirements of the era.

 

Cessna was no exception, and it took an interesting approach to developing a new model in September 1959. 

 

Historically, Cessna would modify civilian types for military use. For example, the 310 became the U-3, the 185 became the U-17, and the 172 became the T-41. In the case of the 407, the company reversed the process, using the existing T-37 “Tweet” primary jet trainer as a starting point and modifying it for civilian use. By installing new engines and modifying the cabin section, it aimed to convert the two-place military trainer into a comfortable, four-place personal jet.

 

There was some precedent for this new category of aircraft. Just seven months prior, French manufacturer Morane-Saulnier introduced the MS.760 Paris, a four-place jet with similar dimensions. With both military contracts and civilian sales secured, Morane-Saulnier appeared to have found multiple markets and would ultimately go on to build more than 200 examples.

 

Never one to happily cede market share, Cessna observed that it could pursue the blossoming personal jet market and also possibly secure some additional military contracts with minimum investment. By utilizing many of the same components and tooling as the T-37, much of the necessary development work could be avoided. Building a full-scale wooden mock-up and beginning construction of the first prototype, the marketing group began a sales tour, pitching the concept at various locations around the U.S.

 

Outwardly similar to the T-37, the 407 utilized the same tail section and wing as the jet trainer but repositioned the engine nacelles 9 inches outward to create more internal space. The cabin utilized this additional space to accommodate four passengers and their baggage. Occupants could easily step into the low-slung cabin without the need for separate steps or ladders, a welcome change from the MS.760, which required occupants to climb a stepladder and clamber into the cockpit from above—decidedly unsophisticated for the target customers of luxurious private jets.

 

Ultimately, like some other intriguing concepts from Cessna, the 407 was not to be. The mock-up pictured was, in fact, a T-37 with a wooden cabin section. And while construction of actual cabin sections was underway, the entire 407 project was abandoned in favor of the massively successful Citation family, the first of which flew in 1969. Interestingly, the FAA registry shows that Cessna registered a 407 as N34267, with serial number 627, indicating the project was full steam ahead, right up until the end.

 

[red750]

The Scaled Composites Model 81 Catbird is a high-efficiency five-seat single-engine all-composite general aviation aircraft designed by Burt Rutan. It is unusual in that it incorporates both a small forward wing and a small conventional horizontal stabilizer on the tail.

 

The Catbird was designed by Burt Rutan while his company, Scaled Composites, was owned by Beechcraft. The design was intended to replace the long-produced Bonanza. The financial situation of Beech at the time, and competing projects, prevented consideration of commercial production. In 1988 Beechcraft sold Scaled Composites to the partnership of Rutan and the Wyman-Gordon Company, who also acquired the rights to a number of the designs, including Model 81 Catbird.

 

The aircraft was stored inverted from the ceiling of Scaled Composites' Mojave hangar until April 2011. The aircraft was restored to flying condition by Zach Reeder, Jim Reed and Mike Melvill. Catbird's second first flight was July 7, 2011.

 

Catbird holds the world record for speed over a closed circuit of 5,000 km without payload of 334.44 km/h, set in 2014 in Category C-1c, Landplanes with take-off weights from 1000 to 1750 kg.

 

The aircraft won the CAFE Foundation's 1988 California CAFE 400 race flown by Mike Melvill, in which aircraft compete for performance efficiency, as measured by fuel consumption, speed and payload. Piloted by Dick Rutan, it subsequently won the 1993 CAFE Challenge with a record score and a speed of 210.73 mph (339.14 km/h), fuel consumption of 20.15 mpg (US miles and gallons) and a payload of 976.63 pounds (442.99 kg).

 

In 2014, the Catbird set another record, for speed over a closed 2,000 km course, from Mojave to EAA AirVenture Oshkosh, with an average speed of 339.50 km/h (211 mph).

 

[red750]

The Otto Celera 500L is a business and utility light aircraft developed by American startup, Otto Aviation. By November 2021, 55 successful test flights had been completed, as introduction is targeted for 2024–2025. It has a single RED A03 diesel piston engine in a pusher configuration and can seat six passengers. It is named after the latin word for 'fast,' celer.

 

Otto Aviation Group, LLC was established in 2008 by Bill Otto to develop the Celera 500L. William Otto has been a research scientist at Los Alamos Scientific Labs, systems engineer then chief scientist at North American Aviation. Otto Aviation is privately funded since 2008 and is seeking a Series B fundraising round: 200 million dollars are needed for FAR Part 23 certification in three years. Construction of the airplane commenced in 2015.

 

The aerodynamic prototype made its maiden flight in January 2018, and began performance testing in September 2019. Otto publicly announced the aircraft and its development program in August 2020, and noted that 31 test flights had been flown to date.[6] By then, a weight-optimized conforming prototype with cabin windows and longer landing gear was expected to fly within 18 months. FAA certification and deliveries are targeted for 2023–2025. By March 2021, the prototype had achieved over 35 hours of flight tests, interrupted by the pandemic until Q3 2021, before two additional flying prototypes join the program.

 

By October 2021, the company had raised more than $50 million. The prototype should reach a fuel economy of 30 mpg‑US (7.8 L/100 km) in cruise, to be improved with integrated heat exchangers replacing radiators nacelles. A second turbo-compressor should allow reaching a 38,000 ft (12,000 m) altitude, and a third for 50,000 ft (15,000 m).

 

In 2022, Otto announced a partnership with ZeroAvia to build a hydrogen-powered version of its aircraft. Introduction    planned 2024-2025.

 

 

 

[skippydiesel]

Until I saw the last photo (above) I did not appreciate how tiny the Ligeti Stratos was.

What;

• Were the engine options?
• Was the performance?

[skippydiesel]

Otto Celera 500L

 

If its performance claims are even close to being true, this is one extraordinary aircraft.

 

A perfect demonstration of what not being wedded to traditional designs, airframe materials and engine can achieve.

[skippydiesel]

Scaled Composites Model 81 Catbird

Powered by 210 hp - I would expect it to be fast - 181 knots not bad for a 4 seater.

I wonder what its stall speed is ? - with all those lifting surfaces I would hope low.