The Ball-Bartoe Jetwing at the Wings Over the Rockies Air and Space Museum in Denver, Colorado, is a one-of-a kind, head-scratching marvel. This single-engine, âblown-wingâ taildragger jet was donated to the museum in 2007 from its previous home at the University of Tennessee, but the aircraft is a Colorado native through and through.
Are you an aviation enthusiast or pilot? Sign up for our newsletter, full of tips, reviews and more!
Powered by a Pratt & Whitney JT15D-1 rated at a maximum continuous thrust of 2,050 pounds, the engine lacks a conventional tailpipe. All thrust was diverted over the wing to improve aircraft short-takeoff and landing capability (STOL), and it is the only aircraft in the world designed in this manner. A spoiler-thrust reverser nozzle in each wing-redirected jet exhaust provided a primitive but effective reverse thrust system. A removable upper airfoil was attached to recoup lost thrust by directing it downward and aft toward the wing- trailing edge. Itâs a small aircraft with a 21-foot, 9-inch wingspan, a length of 29 feet and a takeoff weight of 3,336 pounds. During testing, the âupper blowing surfaceâ technology of the Jetwing yielded twice the lift above and beyond the lift characteristics intrinsic to the airfoil shape.
Ball Brothers Research Corporation president and engineer Otto E. âPeteâ Bartoe designed the Jetwing in 1973 with the help of University of Colorado machinist friends who built it. As a joint venture with Ball, its intent was to attract military and commercial contracts. After the aircraft was built, it was shipped to Edwards Air Force Base for wind tunnel testing. Lockheed test pilot Herman âFishâ Salmon flew it for the first time on July 11, 1977, from the Mojave Airport, flying it 47 times before Bartoe himself flew the aircraft back to Boulder, making 11 fuel stops along the way (it had a small 106-gallon belly fuel tank). Jet fuel was scarce en route, so Jetwing builder and master mechanic Brad Davenport chased Bartoe in a pickup truck with a container of Jet A. Once back in Colorado, Bartoe continued testing the aircraft but was unable to attract any outside investment. Ball donated the aircraft to the University of Tennessee Space Institute in Tullahoma in 1978.
In the early 1980s, the Navy became interested in the Jetwing as a proof-of-concept STOL aircraft for use on shortened aircraft carriers. Test pilot, engineer and University of Tennessee Space Institute staff member Dr. Ralph Kimberlin was contracted to test-fly the Jetwing. He told Plane and Pilot that he enjoyed the agility of the aircraft, but the thin horizontal tail presented problems, saying, âIt had a sharp leading edge.â It would stall in the downwash of the flaps if they were set beyond 45 degrees (full flaps on the Jetwing is 60 degrees), causing a sudden nosedive. Not exactly a desirable trait for landing! The aircraft also required Dr. Kimberlin to use the âbackside landing techniqueâ (utilizing thrust for glidepath control and elevator for speed). He noted that touching the tailwheel down first was easy, but with the blown wing âstill flying,â the main gear stayed âstuckâ about 2 to 6 feet in the air until he figured out how to finesse the thrust to idle. While Dr. Kimberlin three-point landed the Jetwing every time, he noted that âFishâ Salmon wheel-landed the aircraft every time.
In the end, the Navy discontinued blown-wing research in favor of vectored thrust technology, a decision Dr. Kimberlin disagreed with heartily. The Jetwing headed back to Colorado to grace the floor of the Wings Over the Rockies museum. Pete Bartoe retired and as of this writing is 92 years old, living in the Colorado mountains. The Jetwing was Bartoeâs last major aircraft design endeavor.