Raptor Aircraft Raptor
The Raptor was a four to five-seat single-engined canard-wing homebuilt light aircraft, whose prototype was under development by Raptor Aircraft of Ball Ground, Georgia, United States. The Raptor's tricycle landing gear was fully retractable, and the streamlined pressurized airframe was to be optimized for a fast cruising speed at high altitudes. The aircraft was intended to be supplied in kit form for amateur construction.[1][2]
Raptor | |
---|---|
Prototype Raptor | |
Role | Homebuilt aircraft |
National origin | United States/Australia |
Manufacturer | Raptor Aircraft |
Designer | Peter Muller |
First flight | 10 October 2020 |
Status | Development ended |
Number built | one prototype |
The aircraft's designer is Australian Peter Muller,[3][4] whose design goals were to provide a fast, spacious aircraft with IFR capability. Muller intended that the kit would be sold "at cost".[5][6]
The prototype made its first substantive flight on 10 October 2020.[7]
During a ferry flight on 6 August 2021 the Raptor prototype crashed in a cornfield, suffering substantial damage. Subsequently, Muller announced that development of the Raptor would end and the company would move onto developing a derivative design, the Raptor Aircraft Raptor NG.[8]
Design and development
The Raptor was a canard design whose main wings have no flaps, a feature which may extend landing and take-off distances, but whose reduced drag may allow higher speeds and reduced fuel consumption. Instead of a fuselage-mounted fin and rudder, each main wing has a winglet and rudder. The tricycle landing gear is fully retractable. The aircraft has been designed (following the area rule[1]) using CAD techniques, and was constructed primarily of carbon fibre, glass fibre and epoxy. The Raptor is to be powered by an Audi 3.0 TDI automotive conversion[9][10] driving a constant-speed pusher propeller and giving a design cruise speed of 300 kn (556 km/h).
The company made a point of favourably comparing their aircraft against the Cirrus SR22, which has been the world's best-selling general aviation airplane every year since 2002.[11] Raptor Aircraft claim that its plane, compared to the SR22, will be roomier, with a much higher speed, much lower drag, much better economy, and a much lower purchase price. The "finished and flying" price, including engine, is intended to be under US$130,000, with an intention to bring that below $100,000.[6] Prospective buyers made a $2,000 deposit, held in escrow. By December 2018, 1,500 deposits had been received and the company had stopped taking further deposits.[12] The company does not advertise conventionally; rather it posts regular video bulletins on YouTube to illustrate progress to interested parties.
The company proposed that the Raptor would be suitable as a new air taxi aircraft and for light cargo services[13] and they plan on partnering with a company such as Uber.[13] Also, they proposed that a turboprop version would become available in due course. The company claimed they would be "Changing General Aviation in a Big Way", saying:
"We are offering a completed Raptor 'At Cost' and Open Sourcing the whole program so universities and businesses will be able to have access to the design and make improvements and modifications in the same way that open source works in the software world. We will be opening the parts and airframe construction, support and flight training so companies world-wide can compete for your business thereby keeping availability high and prices low. This will also ensure that there is no single point of failure for parts, airframes or support. This distributed model will eliminate any chance of the Raptor not having support. Much like the internet, the open and distributed nature makes it virtually impossible to destroy. The competition will have a difficult time trying to stop us."[13]
In an August 2019 video the prototype was weighed at an empty weight of 3,144 lb (1,426 kg), which is 1,344 lb (610 kg) heavier than originally estimated. At a gross weight of 3,800 lb (1,724 kg) the aircraft's useful load is 656 lb (298 kg). With full fuel of 121 U.S. gallons (460 L; 101 imp gal) the payload is −70 lb (−32 kg).[14][15]
Flight tests
The prototype made a short hop on 21 July 2020, during which it took longer to reach take-off speed than expected and cameras revealed the main landing gear legs exhibited a shimmy on landing. Flight testing took place after those issues were addressed.[16]
The first real flight took place on 10 October 2020 at Valdosta Regional Airport. The aircraft experienced oscillations in yaw and pitch. Also, oil and coolant temperatures were quite high, and climb rate was less than expected, so Muller landed on runway 04 before completing a full circuit. Muller felt that the issues could be caused by not having raised the landing gear, which increased drag and not having the coolant air intake fully open.[7]
On 4 February 2021 during a test flight, the Raptor experienced an oil leak followed by an engine failure caused by an out of position oil seal. The aircraft was glided to an uneventful landing with minor damage from runway contact by one wing tip. During post event testing it was discovered that the #2 cylinder wrist pin had failed as well and an engine swap was required.[17][18][19]
On 6 August 2021, the aircraft suffered an engine failure and was substantially damaged in the subsequent crash in a corn field Nebraska. Designer and pilot, Peter Muller was unharmed in the incident.[20]
Raptor NG
After the crash of the prototype, Muller announced that he was ending development of the Raptor and moving onto development of the Raptor Aircraft Raptor NG. The now unpressurized NG would use a similar fuselage design (but two inches larger in all three dimensions). The Raptor NG would have a shorter box wing design, along with twin electric motors driving ducted fans.[8] The design has been further developed to have a third ducted fan on a vertical axis in the nose, with both main engines able to pivot back 90° to provide upwards thrust and VTOL ability. Some online commentators have, while wishing the project well, reckoned this VTOL plan to be "a bridge too far" and unrealistic for a small firm to achieve.[21] A 2023 detailed technical analysis entitled "Raptor NG VTOL Reality or Renderware?" comprehensively disparages the NG concept as being so mathematically unsound that none of its design targets are achievable.[22]
Specifications (projected)
Data from the manufacturer[23]
General characteristics
- Crew: one
- Capacity: three-four passengers
- Length: 22 ft 2 in (6.76 m)
- Wingspan: 33 ft 9 in (10.29 m)
- Height: 10 ft 0 in (3.05 m)
- Wing area: 167 sq ft (15.5 m2)
- Empty weight: 3,144[14] lb (1,426 kg)
- Gross weight: 3,800 lb (1,724 kg)
- Fuel capacity: 124 U.S. gallons (470 L; 103 imp gal) usable
- Powerplant: 1 × Audi 3.0L TDI V6 turbocharged diesel engine , 300 hp (220 kW)
Performance
- Cruise speed: 300 kn (350 mph, 560 km/h) at 25,000 feet
- Stall speed: 65 kn (75 mph, 120 km/h)
- Range: 3,600 nmi (4,100 mi, 6,700 km)
- Service ceiling: 27,000 ft (8,200 m)
- Rate of climb: 2,000 ft/min (10 m/s) solo
- Wing loading: 21.5 lb/sq ft (105 kg/m2)
See also
References
- "Raptor Aircraft Design". raptor-aircraft.com. Archived from the original on 10 March 2016. Retrieved 3 March 2016.
- Raptor Aircraft (5 March 2016). "Raptor Turboprop Kit Aircraft Just Announced - Press Release". ireachcontent.com. Archived from the original on 28 June 2017. Retrieved 5 March 2016.
- "Raptor Aircraft". angel.co. Archived from the original on 12 August 2016. Retrieved 1 May 2016.
- "11: Peter Muller, Raptor Aircraft: I Believe I Can Fly and Build My Own Plane". Studiomouth. Archived from the original on 7 November 2017. Retrieved 1 May 2016.
- "Raptor Aircraft Home". raptor-aircraft.com. Archived from the original on 25 January 2020. Retrieved 4 March 2016.
- "Raptor Aircraft FAQ". raptor-aircraft.com. Archived from the original on 7 December 2016. Retrieved 4 March 2016.
- Muller, Peter (8 October 2020). "First Real Flight". Medium.com. Archived from the original on 4 May 2022. Retrieved 10 October 2020.
- Muller, Peter (10 August 2021). "Raptor NG — The next generation". medium.com. Archived from the original on 11 August 2021. Retrieved 15 August 2021.
- "Raptor Diesel GT is an Audi TDI Powered Personal Aircraft". Fourtitude.com. Archived from the original on 7 June 2018. Retrieved 1 May 2016.
- Nick Jaynes. "Raptor Diesel GT: Audi-Powered Personal Aircraft - Pictures". Sojourn.Press. Archived from the original on 1 July 2016. Retrieved 1 May 2016.
- General Aviation Manufacturers Association (January 2008). "2007 General Aviation Statistical Databook & Industry Outlook" (PDF). Archived from the original (PDF) on 6 July 2011. Retrieved 2 July 2010.
- "Raptor Aircraft Ordering". raptor-aircraft.com. Archived from the original on 18 January 2020. Retrieved 19 December 2018.
- "Raptor Aircraft Home". raptor-aircraft.com. Archived from the original on 10 March 2016. Retrieved 3 March 2016.
- Raptor Aircraft (27 August 2019). "Success At Last - Building the Raptor Prototype". Archived from the original on 4 May 2022. Retrieved 12 September 2020.
- Raptor Aircraft (2014). "Specifications". raptor-aircraft.com. Archived from the original on 15 October 2014. Retrieved 15 April 2021.
- Muller, Peter (21 July 2020). "It's Airborne!". medium.com. Archived from the original on 25 July 2020. Retrieved 25 July 2020.
- Muller, Peter (7 February 2021). "Things Get Interesting". raptoraircraft.medium.com. Archived from the original on 4 May 2022. Retrieved 7 February 2021.
- Muller, Peter (8 February 2021). "Major Oil Leak Emergency". raptoraircraft.medium.com. Archived from the original on 4 May 2022. Retrieved 10 February 2021.
- Muller, Peter (14 February 2021). "Powerplant Diagnosis". raptoraircraft.medium.com. Archived from the original on 4 May 2022. Retrieved 15 February 2021.
- "FAA Accident and Incident Notification: Notice(s) Created 09-AUG-21". FAA Aviation Safety Information Analysis and Sharing (ASIAS). Federal Aviation Administration. Retrieved 10 August 2021.
- Raptor Aircraft (4 March 2023). "Raptor Aircraft Thruster Update". YouTube. Archived from the original on 27 May 2023. Retrieved 15 May 2023.
- rv6ejguy (17 March 2023). "Raptor NG VTOL Reality or Renderware?". YouTube. Archived from the original on 27 May 2023. Retrieved 27 May 2023.
- "Raptor Aircraft Specifications". raptor-aircraft.com. Archived from the original on 1 February 2020. Retrieved 27 March 2016.