Bell Model 204B / UH-1B Iroquois (in Vietnam), 1964-1965

The Bernard Lindenbaum Vertical Flight Research Collection is a very large collection documenting the history and development of helicopters and V/STOL aircraft from the mid-1940s to the 1990s. The collection contains research reports, conference reports, blueprints, and film documenting this development. Researchers should be aware that, except for the photographs series, the collection was minimally processed in that each box was fully inventoried, but no effort was made to place the material in acid-free folders, number folders, or relocate similar material together. As a result, some boxes will have more than one-topic and the same reports may appear in multiple boxes in the same series or under different series. When researching the collection, researchers should look through all of the boxes with similar headings to locate material. The collection has been organized into thirteen, broad series topics.

Series I, Rotary Wing Handbook, consists of one Record Center box containing eight of the eighteen volumes of the Rotary Wing Handbook. The series also contains Part I and II of the 1960 Russian book “The Aerodynamic Design of Helicopters.”

Series II, NACA & NASA Reports, consists of five Record Center boxes containing National Advisory Committee on Aeronautics (NACA), and its successor, the National Aeronautics and Space Administration (NASA), reports on helicopters, V/STOL aircraft, VTOL aircraft, air foils, and tilted rotors. The date span for the reports is 1929 to 1977. There are also NACA annual reports from 1934 to 1941 and the proceedings of V/STOL Technology and Planning Conference held September 23 to 25, 1969.

Series III, AVRO Avrocar, consists of three Record Center boxes containing reports, progress reports, and photographs on the development of the Avrocar. The reports span a period of development beginning in 1958 and ending in 1962. There is also film of the Avrocar in Series XII.

Series IV, Helicopters, is a fairly large series consisting of eight Record Center boxes containing reports spanning a period from 1934 to 1997. The series includes early, pre-1960 reports on helicopters, blueprints of Kellett and Piasecki aircraft, and helicopter history articles and photographs. The series also contains helicopter brochures and information on early helicopters and towed helicopters.

Series V, Helicopter Aerodynamics, is a large series consisting of twenty Record Center boxes documenting helicopter aerodynamics from 1918 to 1993. The series includes reports on: helicopter dynamics, performance, and theory; rotors, rotor blades, and rotor aerodynamics; rotor blade test and helicopter controls; helicopter airfoils; helicopter vibration; aerial utility vehicles; hot cycle rotors and wing composite aircraft; and aerodynamics and the Kaman Model K-190. The series also contains American Helicopter Society Forum Reports from the 1970s and reports from the 1980 Propeller Propulsion Conference.

Series VI, Convertiplane, Autogiro, Composite Research Vehicle and Stowed Rotor, is another large series consisting of seventeen Record Center boxes containing reports from 1923 to 1999. This series contains reports on: the Convertiplane Model XV-1; stoppable and stowed rotors; convertiplane composite research aircraft; autogiros; compound helicopters; autogiro gliders and kites; tip-mounted power; and compound and rigid rotor helicopters.

Series VII, SR-175, Tri-Service Transport and V/STOL Transports, consists of nineteen Record Center boxes containing reports from 1938 to 1990. The topic of these reports center on tri-service and V/STOL transports. Included in this series are reports from the 1st National V/STOL Aircraft Symposium held November 3-4, 1965. The series also includes a wide-variety of other topics including: the Bell SR-175 and ducted propellers; the tilt-wing propelloplane; lift fans and fan-in-wing; V/STOL short-haul transports; the Bell X-22A program, and reports on tilt wing V/STOL aircraft including the Canadair CL-84, Hiller X-18, VFW VC 400, and LTV XC-142A. The series also contains reports from the Academic VTOL and American Helicopter Society Proceedings and the First Convertible Aircraft Proceedings, and American Helicopter Society Forum reports from 1947 to 1972.

Series VIII, Vertical Lift Theory and Aerodynamics – Non-Helicopter, is one of the largest series in the collection spanning twenty-five Records Center boxes. The reports span a period from 1932 to 1989. Included in this series are reports on: tri-service transports, the Harrier; V/STOL propeller technology concepts; lift-fan flight research; high-lift devices; V/TOL and GETOL ground effects; tilt-wing aircraft; downwash and ground effects; shrouded propellers and propulsion systems; stopped rotor compound helicopters; and ducted and shrouded propellers.

Series IX, Escape Systems, Crash and Rescue, is a small series consisting of three Record Center boxes. This series includes reports from 1929 to 1999 that include information on escape systems and crash rescue helicopters.

Series X, Power Plants, Propellers, RPV, Drone, Small Tactical Aerial Vehicle, and STAMP, is another small series consisting of four Record Center boxes. The series includes information on: drone aircraft; remotely piloted vehicles; power plants; propellers; and the Small Tactical Aerial Mobility Platform (STAMP). The series also contains reports from the Conference on Propeller Propulsion held April 22-24, 1980 and a copy of Lindenbaum’s presentation on “V/STOL Concepts and Developed Aircraft: A Historical Review.”

Series XI, Microfilm, is located in one box (Box 106) and includes the records of the Prewitt Aircraft Company, Clifton Heights, Pennsylvania. The microfilm contains reports on the history of the helicopter and rotary wing aircraft history.

Series XII, Film, consists of 190 reels of 16 mm film and 10 VHS cassettes in documenting vertical flight reports and history from 1938 to 1977. Some of the film is in poor condition and all need to be converted to digital format for viewing. The series includes film of the Lockheed XV-4B Hummingbird, the LTV XC-142, and the AVRO Avrocar, plus film of many other vertical flight aircraft.

Series XIII, Aircraft Photos and Pictures, consists of 19 binder boxes (Box 121-139) and one flip-top legal size document case (Box 140) containing photographs, pictures, illustrations, and some negatives of various rotary wing, fixed wing, and V/STOL aircraft found throughout the collection. Photo items described in each group are presented in alphabetical order by the last name of the inventor or builder (prior to WWII) and by the aircraft manufacturer’s name (WWII and after). Aircraft models built by a manufacturer are generally presented starting with the earliest model number and ending with the latest model (or concept design). There are some cases where different aircraft (such as helicopters and V/STOL aircraft) are found together under the same manufacturer. The series is organized into six subseries and broken down as follows:

Subseries XIII A. Rotary Wing Aircraft (Pre-WWII) contains images of Autogiros, Convertiplanes, & Helicopters, as well as Cyclogyros, Ornithopters, and other rotary ring aircraft.

Subseries XIII B. Fixed Wing Aircraft (Pre WWII through Post WWII) contains images of U.S. manufactured military aircraft consisting of single and multi-engine fighters, bombers, transports, and experimental fixed wing aircraft. Also included are U.S. captured German and Japanese military aircraft. Manufacturers include Bell, Boeing, Curtiss, Douglas, Lockheed, North American, Republic, Vought, and Vultee.

Subseries XIII C. German Rotary Wing Aircraft (WWII), consists of images of U.S. captured German military helicopters and a rotary wing kite, and some aircraft later reconstructed and flight tested by the U.S. Air Force following the war. Manufactures include Flettner and Focke-Achgelis.

Subseries XIII D. U.S. Rotary Wing & V/STOL Aircraft (WWII & later), contains images of U.S. conceptual and manufactured aircraft models (commercial & military), consisting of autogiros, helicopters, convertiplanes, compound helicopters, and various experimental V/STOL aircraft. Manufacturers include Bell, Bensen, Boeing, Cessna, Hiller, Hughes, Kaman, Kellett, Lockheed, LTV, McDonnell, Piasecki, Pitcairn, Ryan, and Sikorsky.

Subseries XIII E. Foreign Rotary Wing & V/STOL Aircraft (Post WWII) contains images of foreign conceptual and manufactured aircraft models (commercial & military). These consist of autogiros, helicopters, compound helicopters, and various experimental V/STOL aircraft from the countries of Canada, Federal Republic of Germany (F.R.G.), France, Italy, Japan, Soviet Union (U.S.S.R.), and United Kingdom (U.K.). Manufacturers include Aerospatiale, Breguet, Canadair, Dornier, EWR, Fairey, Hawker-Siddeley, Mil, Sud Aviation, and VFW.

Subseries XIII F. Rotary Wing & V/STOL Aircraft (U.S. & Foreign) – 9 x 12 and Oversize Prints, contains U.S. and foreign manufactured models (commercial & military), consisting of single & multi-engine helicopters, XV-15 tilt rotor, and artist’s conceptions of compound helicopters and V/STOL aircraft. Manufacturers include Agusta, Bell, Curtiss-Wright, and Sikorsky.