I met the test pilot of this wing, Monty Bell some time ago and got the following information from him. He stated the wing worked quite well and the pilot in wing design allowed him to walk around inside the wing, even assisting other pilots, with the wing hanging from shoulder straps. Apparently the wing used elevons and a bell shaped lift distribution (after the Hortens) achieved though the carful selection of airfoil sections across the span to control adverse yaw. No tip rudders or additional devices were needed.
Monty states he has a 12 m RC model he still flys - though I never saw it- and retains plans for the full scale version. He said he is looking for a composite engineer so he can build another one.
Monty states he flew the wing repeatedly on numerous occasions with several high flights with no problems and excellent performance easily beating flex wings. Apparently he was testing the wing at Torre Pines and attempted to spin the wing at 300 feet - against the builder Rohl Klingburg's express wishes.
Monty was unable to recover from the spin test so low and crashed the wing. He states the protection inside the wing was so good he escaped mostly uninjured. The designer decide to adandon the project follwing this incident.
There has been speculation that a hole in the center of the wing is what has caused almost all pilot in wing designs to fail - the Delka, Flair, Klingburg wings.
Despite often stated "fact" - there are no plans for the full size Klingberg Wing. I built the wing without plans (never drew them) and used only a few templates for making parts. As a long time model builder, pilot and engineer, I simply didn't need plans for a "one-off" design. The truth is that the test pilot (Daryl "Monty" Bell) stole the Wing after the crash at Torrey. The Wing was too damaged to provide sufficient information for a second Wing to anyone other than the designer (me). If anyone knows the locations of any remains, I would like to have that information. I still have three feet of the left wing tip (the one that impacted the cliffs). The engineering facts surrounding the failure of the Wing is that I modified standard airfoils for the tips. The modification I made combined with the low Reynold's number caused the design to have tip stall problems. A technical report of the problem was published in Hang Glider magazine in the late 1980's. The right wing had slightly less twist due to a construction error and in a stall the Wing would drop the right wing. Recovery could be made by simply returning the ailerons to a neutral setting. The test pilot made the error of flying too slow twice. Once at altitude with room to recover and once low without room to recover. At Torrey, the wind was too low for soaring flight and the test pilot attempted to stay aloft by flying slow. A beginner's type error. As I watched at the edge of the Torrey cliffs I saw the Wing flying near stall speed and was not surprised to see it drop the right wing. The test pilot did not perform the correct recovery process and crashed. As a final word - I attempted to recover the remains of the Wing from the test pilot a few months after the crash (years ago) but was unable to do so. In the process, I had extensive discussions with the local law enforcement officials and they pointed out to me that Monty Bell had a number of "encounters" with the local police and was considered to be an on-going problem for them. I recommend that people who encounter him should steer clear. He is full of false information and potential trouble. I'm one of a long list of people who have had a bad experience with him. Beware.
I recently ran across the pictures I took of the first flight of the Klingberg wing, with Rol as pilot. It's the reason I decided to do a search for it. I helped Rol do some of the testing and minor design stuff, as he had already done the vast majority by the time I first saw it. It was a highly anticipated event, and the group of us that went to watch this flight were all pretty excited about it - particularly Rol!. It went off without a hitch, and Rol cracked open a bottle of champagne as we all celebrated his maiden flight. Rol, if you read this, please get in touch - it's been years since we've spoken
Back in early 90's, a friend here in Australia gave me a copy of footage of Rol Klingbergs first load testing in a backyard, plus first beach runs; beach glides; soaring flights at beach cliffs and i guess Torre Pines, with post flight discussion between Rol and test pilot. Quality is 60-70%. but still totally inspiring. I've transferred it across to dvd, and use it as reference material in my concept designing for a new format of H/G come SAILPLANE. Might be able to forward copy back to U.S.A. if you gentlemen no longer have access to footage.
I was there and I rember it well...I have photos, Monte did not steel any thing..
I am trying to build a new wing based on Horten wings profiles. Does anybody have wing plans that I could use?
Or any specific advicecould be helpful, on yaw stability and yaw/roll coupling for examples.
Thanks a lot
Is the wing based on any particular NACA spec?
Dear Capsos, There is - but I have lost it because in Gmail's drafts department, the Save button is next to the permanently destroy button. I should be able to track it back. In the meanwhile, have you seen this:
It seems like the numbers are there to do design work in the NASA paper here amaflightschool.org/PRANDTL The development being, keep the elevons at the tips to receive proverse yaw. www.youtube.com/watch?v=xnlJpzik75k
Brett says: "He [Monty Bell] was testing the wing at Torre Pines and attempted to spin the wing at 300 feet".
This would appear to be lunacy. The procedure for recovery from a spin in a standard a/c is: Stick fully forward,full opposite rudder. To tackle such a manoeuvre, he should have started at 3000' and be ready with his parachute.