the technology

The FanWing experimental aircraft opens up a new area of aerodynamics   Designs to establish a means of integral lift and thrust using a horizontal-axis wing rotor are recorded back as far as the late 19th century. Some of the experiments started to take off but did not sustain flight. The FanWing blown-wing solution offers both basic proof of concept and a steady trajectory of improved and controlled flight performance.

The idea  The aircraft has a cross-flow fan along the span of each wing. The fan pulls the air in at the front and then expels  it over the wing's trailing edge. In transferring the work of the engine to the rotor, which spans the whole wing, the FanWing accelerates a large volume of air and achieves unusually high lift-efficiency.

Proof of concept  The FanWing showed proof of concept in the form of actual flights before theoretical validation, academic research or explanation. The FanWing is an invention by trial and error and though certainly employing a methodology with good precedent in the history of innovation it is in no way within the normal paradigm of academic and conventional aircraft development. There is nevertheless a steady accumulation of tests and supporting documentation.

Wind tunnel tests  First wind-tunnel tests were conducted in 1998 by Pat Peebles at the University of Rome. Several universities in various countries have carried out experiments since then independently and sometimes with input from Pat Peebles, notably two wind-tunnel projects for student dissertations requested and supervised by Professor JMR Graham at  Imperial College, London, using prototype wings loaned by the FanWing Company.  Limited wind-tunnel tests were also completed in the company workshop.

In 2002 a UK Government SMART Award and private investment in the FanWing company funded a series of wind-tunnel tests, providing a basis for construction of a new prototype. The company series of tests was completed at  Imperial College with Klaus Kogler assisting FanWing inventor Pat Peebles and with data consultation by Professor J M R Graham.

Efficiency  Documented efficiencies for the first prototypes were found to be in the order of 20 grams of lift per Watt of shaft power, indicating an initial lift of 1 –1 ½ tons of weight in the air with 100 hp.  Initially, wind-tunnel optimisation at Imperial College (in the company's 2002 series of tests) indicated 29 g/W.  Most recent modifications in wing geometry now indicate in limited linear flight tests (June 2009) an unexpected increase in efficiency up to 35 g/W translating to 26 kg/hp or 2.6 tons for 100 hp. At this initial stage of development, results are based solely on onboard power measurement.

Tests to date have been completed on small wings with low wing-loading. 

Speed  Flight speeds have ranged from 3m/sec for the smallest model to 17 m/sec for the largest model. Eventual maximum speed remains open to speculation. The prognosis is good:  present results are based on minimum experimental resources with  eficiencies and speeds nevertheless continually improving. 

The proposed CargoLift UAV design concept weighing 5,500 kg (12,000 lbs) will have an estimated flight speed of 36 m/sec (70 kt) at sea level. At higher altitudes the speed will increase doubling at 5,500 m. while maintaining the same flight efficiency. 

The FanWing will not have the same altitude speed problems as a helicopter, which is limited in speed by both the advancing and the retreating blade.

Ultralight Simulation Project  First manned FanWing Ultralight graphics  based on Pat Peebles' specifications  were commissioned  by FanWing in 2005 from Jon Linney, KMi, Open University UK and funded by private investment combined with a  UK Government Jumpstart Connect Award from the London Development Agency. The graphics triggered a new Imperial College Simulation project.  X-Plane software was used to establish  flight characteristics of the first manned FanWing Ultralight. The simulation project based on Peebles' specifications and designs was completed by Oliver Ahad at Imperial College June 2006 and supervised by Professor J M R Graham with Pat Peebles as consultant.  (A new simulation video is available either on YouTube or the dedicated Simulations page on this website.)

A UK National Award, the John Barnes Award, offered by the Association of Aerospace Universities, was presented to Oliver Ahad for his FanWing Ultralight Simulation project.  The dissertation can be requested from Imperial College. See also: Flight simulation and testing of the FanWing experimental aircraft;   Authors: O.Ahad, J.M.R. Graham;  Journal: Aircraft Engineering and Aerospace Technology ISSN: 0002-2667 Year: 2007 Volume: 79 Issue: 2

Documentation  Originals of  the Imperial College FanWing project  dissertations are kept at  the College. These and further data from the SMART project can be accessed with formal non-disclosure agreement by direct request to the FanWing Ltd Company.

The simulator files can now be downloaded.  FanWing Ultralight Simulation

Unmanned: STOL UAV.  In 2007 flight tests the STOL UAV surveillance prototype showed unusually short take-off ability, leaving the ground after a 1 m roll (without payload) and 3m on lower power (see video on this website and Flight  online archives).  It is estimated that at maximum weight (12 kg) the small surveillance aircraft could leave the ground in three lengths. The new prototype was developed as an urban surveillance UAV.  The aircraft flies slowly and will be able to manoeuvre urban 'canyons' with take-off independent of a catapult. The efficiency of the aircraft indicates that it will have an autonomy of close to 80 minutes  with a 2 kg payload under electric power. The short-take-off capabilities make the application useful for operations originating from a  rooftop or short section of road. The aircraft will be simple to dismantle and assemble for transport and deployment.

Runway-Independent Aircraft  Development started in January 2005.  First positive VTOL capability based on a  new design was confirmed November 2005 with workshop tests on an indoor tethered model.  A new patent application was deposited April 2006 with PCT process registered March 2007. As of this year, 2009, National Phasing for the VTOL FanWing has been confirmed in forty countries.