This picture was provided to TWITT by Jim Theis in June 1999. It truly sparked our interest.  Keep scrolling.

Some Nighthawk control motions.  What the tail does is obvious from the pictures in terms of its movement up and down and twisting to produce the desired elevator/rudder effects.  The wing warps up, down, left up, right down (and vice-versa) and separates like a split flap.  The various control motions are intended to overcome the need for a vertical surface of any sort - and this has been the major control problem to date (1979).  The power package is a Soarmaster that utilizes an 8 hp Chrysler (West Bend) engine.  Technical inspectors were wary of the unsupported prop shaft, but Jim demonstrated to their satisfaction that it would operate safely and was allowed to fly at Oshkosh.  (Source:  Sport Aviation, October 1979, p. 40)  For a more recent update click here.

Jim Theis literally wears the Nighthawk.  The control bar just below his chest area moves forward and back, swings left and right.  Then each side can make these movements independently of the other.  Push one or both side down and the telescope out of the vertical tubes. . .and (gasp!) repeat all of the above motions.  There's more - but you get the idea.  Learning to fly by instinctively coordinating all these movements is the tough nut Jim is presently (1979) trying to crack.  What appears to be a graduated beaker out in front of the crash bar is a Hall Wind Meter (airspeed indicator).  (Source:  Sport Aviation, October 1979, p. 39)


(The following text is more current material from Jim Theis about this very interesting project.)

                                                                                                                                                        July 2, 1999

Nighthawk I (Phase I): Bird like lateral control and wings capable of twisting through +/- 25 deg under pilot command in flight;  propulsion pusher prop (Soarmaster).
     There are over one hundred pictures including details of assembly and various shots of aircraft structure.  There is also much 8mm and about 10 minutes of 16mm film footage of the aircraft as it progressed from ground runs> to first flight >to a well behaved proto-bird.  The 35mm prints and slides,  and super 8mm were taken by my wife, Linda who also helped with testing, documentation and building.  The photograph shows the Phase I Nighthawk project as we debugged the birdlike lateral control system during 1979. 

Nighthawk II (Phase II): Replace the Pusher Prop with Flapping Wings; refine wing design to including sweep and span reduction during upstroke, and several other modifications including carbon spar...
     During the intervening 20 years, a foundation theory of flapping wing propulsion was developed and a research effort completed to develop a light, efficient , simple flapping wing drive concept.  At least a dozen of the scores of concepts conceived to flap the 42 foot span wings of the Nighthawk II were reduced to numbers and drawings.  Only one made it completely through the process successfully.  Some of the concepts took a year to analyze in and around making a living as VP and chief design engineer of small turbines for Air Turbine Technology, Inc. (Company was sold in 1989 and my brother, Charley and I started up a wheelchair development company and moved our families from S. Florida to SE Minnesota). 
     Three years ago, July '96, we licensed our wheelchair technology and I became a full time flapping wing aircraft designer. Linda has sponsored the design effort (which is how my wife became my boss...).  Like the Prop driven Nighthawk I, the Nighthawk II will be an ultralight (<254 lbs, stall, max speed within parameters of FAR part 103...), and I will once again become a test pilot. 
     As fate would have it, we are truly on a time line that parallels the Wright Brothers a hundred years displaced.  I expect us to go through similar learning curve and through at least one complete design revision as we move forward to successful first flight with flapping wing propulsion (hopefully before Dec. 17, 2003). Having read the same article in Sport Aviation as Jim Marske, I likewise planned to use Graphite pultrusion carbon rods in the construction of various components.  Jim is now a factory rep for AVIA SPORT's rod, which is superior to the Graphlite product.  If you have Jim's e-mail address, please forward this note to him.  He may be interested in helping with our project, or at least in being in the communications loop.
     We have the domain name; my son Charlie is putting together the site.  The whole story of this project will be accessible from there.  We will build and test the Nighthawk II  real time on the web, limited only by resources to present the material. 
     The work has been documented since its beginning in January of 1974 in twenty bound log books (National brand 5x5 quad) and seven bound sketch books (200 pages each).  Since the days of Super-Calc (Osborn I and II >CPM) and more particularly Lotus, the analytical work is done using spreadsheets.  There are many, many spreadsheets documenting the evolution of thought about the physics of flapping wings.  The formal drawings are mostly AutoCad.dwg files, but I have recently transitioned to Bentley Systems 2/3D cad.  Before I broke my back I used typical pen/ink drafting.
     Since '89 we have had to work on a shoe string budget  For several years my family lived in the shop while we built up the wheelchair technology to a marketable level.  During that time I did a sole source turbo-alternator design for the Naval Weapons Power System group at China Lake, which was the source of about all the cash we had to live on till we licensed the wheelchair technology in '94.  In '94 we had our first real theoretical break-through, then in November of '96 the "final?" and most important piece of the puzzle of flapping wing propulsion (to date) was discovered... by mid '97 we had the first spreadsheet that could produce a flap rate, using our flapping system and wings, about as low as a similar sized Great Blue
Herron.  Finally, this year,  a solution was conceived to produce a drive  to implement the flight mechanics dictated by the discoveries and confirmed by the spreadsheets; ...the drive is our "Wilbur Wright Bicycle Inner Tube Box... discovery" and as a result we can finally go forward with drive system hardware.  We will begin building this year and testing this winter (there's only so much time we can spend making less than 150 lbs of parts... we have a sponsor that will manufacture one of the critical drive components to spec...).

For us, it is indeed true that The Wing is The Thing:    for propulsion!

Our aim is to make a first step towards low power, highly maneuverable, flapping wing  Local Flight..., Bird Like Flight.

                                                                                                                                                  July 25, 1999

It's very hard for me to think of Ornithopters as anything other than an extremely useful new class of aircraft that we have only just barely gained the ability to design, build and fly successfully.  Sometime between now and the Wright Centennial, the first piloted, powered Ornithopter will fly.  After that we will begin a very exciting and challenging aircraft technology, and theoretical aerodynamics development period.   Our team will contribute our bit.

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