Mandel Lenkowsky Early Vertical Flight Development Collection, 1936-1946
NASM.1989.0099

Summary
Collection ID:
NASM.1989.0099
Creators:
Lenkowsky, Mandel
Dates:
1935-1952
Languages:
English
English
Physical Description:
2.18 cubic feet
(2 records center boxes)
Repository:
National Air and Space Museum Archives Division
This collection includes notebooks containing scientific notes and mathematical calculations, a random assortment of journals and periodicals, published reference books, and a few advertising and promotional brochures all pertaining to American experimental military and commercial vertical flight from the late 1930s to the late 1940s. The collection also contains photographs of the following helicopters: Sikorsky XR-1, XR-4, YR-4, XR-5, XR-6, XR-6A, VS-300; Kellet XO-60 and XO-61; and Rotachute P-4. Also included are photographs of helicopters by Pitcarin, Landgraf, Greyhound Bus, Spratt, Berliner, Ochmichen, and DeBothezat.

Scope and Contents note
Scope and Contents note
The Mandel Lenkowsky Early Vertical Flight Development Collection contains correspondence, manuscript notes, notebooks of scientific and mathematical notes, periodicals, and published reference materials about experimental military and commercial vertical flight from the 1930s to the 1940s. The collection includes photographs of the Sikorsky XR-1, XR-4, YR-4, XR-5, XR-6, XR-6A, VS-300; Kellet X0-60 and X0-61; and Rotachute P-4 helicopters; as well as the Berliner, DeBothezat, Greyhound Bus, Landgraf, Ochmichen, Pitcairn, and Spratt helicopters.
The collection contains chapters from Mandel Lenkowsky’s unpublished manuscript,
The Helicopter
, and his correspondence with Macmillan Publishing Company. The book was scheduled for publication in the summer of 1945. In his correspondence, Lenkowsky stated he would like to focus primarily on the development of the Focke helicopter (Germany, 1934-37) and was trying to secure rights to mention it in his book. There is no evidence in the collection that Lenkowsky completed the book or that it was ever published.

Arrangement note
Arrangement note
The collection is arranged into the following series:
Series I: Correspondence and Manuscript Notes
Series II: Scientific and Mathematical Notes, Aircraft Drawings, and Published Works

Biographical/Historical note
Biographical/Historical note
Mandel Lenkowsky was a civil and aeronautical engineer. He attended the Guggenheim School of Aeronautics at New York University from September 1933 until June of 1937. He later attended the School of Engineering at Princeton University from October to November of 1943. His post graduate work detailed the development of rotary wing aircraft. Lenkowsky was employed as an aeronautical draftsman at the U.S. Naval Air Station, Lakehurst, New Jersey, from February 1941 until June of 1941. In August of 1941, Lenkowsky was employed by the Army Air Forces (A.A.F.) Materiel Center, as a project engineer. Lenkowsky resigned from the Army Air Forces at Wright Field in Dayton, Ohio, in October of 1944 to dedicate full time to the completion of his book on the development of the helicopter.

Administration
Processing Information note
Arranged and described by Roseann E. MacLean, 2004.
Encoded by Amanda Buel, 2015.
Author
Finding aid prepared by Roseann E. MacLean
Immediate Source of Acquisition note
Leslie Lenkowsky, gift, 1989, 1989-0099, NASM

Using the Collection
Conditions Governing Access note
No restrictions on access
Conditions Governing Use note
Material is subject to Smithsonian Terms of Use. Should you wish to use NASM material in any medium, Please submit an Application for Permission to Reproduce NASM Material, available at Permissions Requests.
Preferred Citation note
Mandel Lenkowsky Early Vertical Flight Development Collection, Acc. 1989-0099, National Air and Space Museum, Smithsonian Institution.

Keywords
Keywords table of terms and types.
Keyword Terms Keyword Types
Aeronautics Topic Search Smithsonian Collections Search ArchiveGrid
Aeronautics, Commercial Topic Search Smithsonian Collections Search ArchiveGrid
Aeronautics, Military Topic Search Smithsonian Collections Search ArchiveGrid
Aeronautics, Military--Research Topic Search Smithsonian Collections Search ArchiveGrid
Helicopters Topic Search Smithsonian Collections Search ArchiveGrid
Helicopters--Flight testing Topic Search Smithsonian Collections Search ArchiveGrid
Kellet XO-60 Autogiro Topic Search Smithsonian Collections Search ArchiveGrid
Kellet XO-61 Autogiro Topic Search Smithsonian Collections Search ArchiveGrid
Notebooks Genre/Form Search Smithsonian Collections Search ArchiveGrid
Periodicals Topic Search Smithsonian Collections Search ArchiveGrid
Photographs Genre/Form Search Smithsonian Collections Search ArchiveGrid
Publications Genre/Form Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) R-4 (H-4) Family Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) R-6 (H-6) Family Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) VS-300 Family Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) XR-4 Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) XR-5 Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) XR-6 Topic Search Smithsonian Collections Search ArchiveGrid
Sikorsky (USA) XR-6A Topic Search Smithsonian Collections Search ArchiveGrid

Repository Contact
National Air and Space Museum Archives Division
14390 Air & Space Museum Parkway
Chantilly, VA, 20151
Phone: 703-572-4045
NASMRefDesk@si.edu