The Travel Air 4000 is an American general-purpose biplane of the 1920s, a member of the family of aircraft that began with the Travel Air Model A.Taylor 1993, pp.856,865 It was later known as the Model 4.Pelletier 1995, p. 32 Derived from the Model BW, around 100 were built, including two that were converted from Model 2000s.
Design and development Like other members of this family, the Model 4000 is an unequal-span, single-bay, staggered biplane of conventional design. The passengers and pilot sit in tandem, open cockpits. It has a conventional tail, and fixed, tailskid undercarriage. The fuselage is built from welded steel tubes, and the wings from wood.Phillips 1994, pp. 91–92 Travel Air model numbers primarily reflected changes in powerplant, and the Model 4000 was originally powered by a Wright J-5 or J-4 radial engine mounted in the nose, driving a tractor propeller. From late 1928 onwards, however, the Model 4000 and Model 4 designations were applied to aircraft powered by a wide variety of other air-cooled radial engines.Juptner 1962a, p. 94
Travel Air built fourteen Model 4000s in 1927, and the design received type certificate ATC-32 in April 1928. Most Model BWs were registered under the same type certificate.Pelletier 1995, p. 23
Starting with the Model B-4000, some variants had a new "outrigger" style undercarriage, where oleo struts were attached outboard of the main undercarriage units, connected to struts forward of the lower wing.Pelletier 1995, p. 33
Model 4000 variants are distinguished by changes in their wing type and powerplant, although other characteristics such as undercarriage changes or roles such as mailplane or aerial spraying are sometimes also reflected in the model numbers.
The wing types are as follows:Phillips 1994, pp.91,93
Wing type Airfoil Description Year introduced Type A Travel Air #1 Aerodynamically balanced ("elephant ear") ailerons, no fuel tank 1925 Type E Travel Air #1Phillips 1994, p. 102 Frise ailerons, no fuel tanks 1927 Type B Travel Air #1Phillips 1994, p. 99 Frise ailerons, fuel tanks 1929 Speedwing Different, thinner wing"Travel Air D4D" Frise ailerons, greater structural strength 1929
Operational history Apart from its use in general avaiation, the Model 4000 was flown competitively. Louise Thaden flew a D-4000 to win the inaugural Women's Air Derby at the 1929 National Air Races.Pelletier 1995, pp. 33–34
They were also used for film work. D-4000s represented World War I Nieuport fighters in The Dawn Patrol (1930), Hell's Angels (1930), and Young Eagles (1930).
Variants Model 4000 standard model with Type A wing and Wright J-5 engine; type certificate ATC-32Phillips 1994, p. 95Juptner 1962a, p. 94 Model A-4000 version with Type A wing and seven-cylinder Floco engine;Phillips 1994, p. 98 type certificate ATC-148;Juptner 1962b, p. 139 9 registered Model B-4000 version with Type E or Type B wing, Wright J-5 engine,Phillips 1994, p. 99 and outrigger undercarriage; type certificate ATC-146;Juptner 1962b, p. 135 25 registered Model C-4000 version built by CurtissPhillips 1994, p. 101 with Type A or Type E wing, and Curtiss Challenger engine,; type certificate ATC-149;Juptner 1962b, p. 141 prototype converted from a D-4000, then 22 registered, plus seven Model 2000s and two E-4000s converted Model BC-4000 version based on C-4000 but with Type B wing and outrigger undercarriage; 1 built, later converted to SBC-4000Juptner 1962b, p. 256 Model SBC-4000 floatplane version of BC-4000; approval number 2-154;Phillips 1994, p. 89Juptner 1962d, p. 131 1 converted from BC-4000 Model SC-4000 floatplane version with Curtiss C-6 engine;Phillips 1994, p. 101 designation might also have referred to floatplane version of BC-4000 Model D-4000 "speedwing" version with Wright J-5 engine;Pelletier 1995, pp. 33–34 some built as single-seaters; approval number 2-84;Phillips 1994, p. 89Juptner 1962d, p. 121 Model E-4000 version with Type E wingPhillips 1994, p. 94 and Wright J-6-5 engine;Pelletier 1995, p. 34Phillips 1994, p. 102 approval number 2-156, superseded by type certificate ATC-188;Juptner 1962b, p. 188 most widely-produced of the Model 4000 family, 59 registered Model BE-4000 version with Type E or Type B wing, Wright J-6 engine, and possibly outrigger undercarriage; 12 registered Model J4-4000 version with Wright J-4 engine; approval number 2-243;Juptner 1962d, p. 143 at least 6 built Model K-4000 version with Type A wing and Kinner K-5 engine;Pelletier 1995, p. 35Phillips 1994, p. 103 elongated nose to compensate for weight and balance changes; type certificate ATC-205; 6 built Model DK-4000 "speedwing" version of the K-4000; 1 built Model L-4000 version created by Parks Air College in 1941 to upgrade the Model 4000s they used as trainers by installing Lycoming R-680-B4 engines. These aircraft had dual controls and their rear cockpits were fitted with folding blind-flying hoods. Model BM-4000 dedicated mailplane version with front cockpit replaced by mail compartment and with redesigned tail fin; Wright J-5 engine type certificate ATC-147;Phillips 1994, p. 88Juptner 1962b, p. 137 at least 7 built or converted Model B9-4000 version with Type E or Type B wing, Wright J-6-9 engine, and outrigger undercarriage; some completed as single-seaters; some later fitted with NACA cowlings; approval number 2-381;Phillips 1994, p. 90Juptner 1962d, p. 167 7 built or converted, including one from a Model 4-DPelletier 1995, p. 37 Model D9-4000 D-4000 modified for Arthur Goebel for airshow flying; speedwings (or otherwise clipped wings), Wright J-6-9 engine, and front cockpit replaced by chemical tank for smoke production; BM-4000-style fin fitted later; 1 converted Model U-4000 alternative designation for Model 4-U Model W-4000 version with Type A wing and Warner R-420 engine;Pelletier 1995, p. 36 approval number 2-35Juptner 1962d, p. 112 superseded by type certificate ATC-112;Juptner 1962b, p. 35Phillips 1994, p. 104 27 registered Model DW-4000 "speedwing" version converted from the W-4000 prototype; Warner R-420 engine; 1 converted Model 4000-CAM alternative designation for Model 8000 Model 4000-SH alternative designation for Model 9000 Model 4000-T experimental major conversion by Curtiss from Model 4-D; new wings with automatic leading-edge slots, flaps of nearly full-span, and Tanager-style "floating ailerons"; 1 converted, in turn later converted to Model D-4-D Model 4-D development of the Model B-4000 with type B wing, Wright J-6 engine,Phillips 1994, p. 112 and outrigger undercarriage; type certificate ATC-254; examples included two converted from Model BE-4000s Model 4-P version with ACE LA-1 engine and NACA cowling; approval number 2-160 superseded by type certificate ATC-280 Model 4-PT alternative designation for Model 4-P Model 4-S experimental testbed for the Powell Lever Motor; 1 builtPelletier 1995, p. 38 Model 4-U catchall designation for early versions converted by Otto Timm to use Comet 7-cylinder radial engines Model D-4-D lightened version with reduced-span wings, Wright J-6 engine, and new undercarriage; approval number 2-178;Juptner 1962d, p. 133 5 registered, plus another 6 converted from other variants Model W-4-B special racing version designed by Ted A. Wells; much shortened wings, Wright J-5 engine, and new undercarriage and interplane strut designs. 1 built. Model Z-4-D dedicated version for aerial spraying and heaviest of all the Travel Air biplane family; Wright J-6-9 engine; 1 built, plus 1 converted from Model 4000
Operators Civilian Parks Air College operated Model 4000s for training transport pilots.Juptner 1962a, p. 95 Some aircraft modified with Lycoming R-680-B4 engines. San Diego Air Service operated the W-4000 United States Department of Agriculture operated the B-4000Juptner 1962b, p. 136 United States Department of Commerce operated the B-4000
Military Peruvian Air Force operated at least one E-4000Hagedorn 2006 p. 88
Surviving aircraft
This is a partial list of surviving examples of the Model 4000 and its subtypes, confined to aircraft that are still in commercial use, in museums, or in some other way notable. construction number 374, registration NC4321 (current in 2024"Aircraft Inquiry" ). As of 2024, this aircraft was bring used to offer scenic flights over the San Juan Islands."Cap'n Mac's Magic Air Biplane Tours" construction number 416, registration N1004 (current in 2024"Aircraft Inquiry" ) at the Mid America Flight Museum, Mount Pleasant, Texas"Travel Air 4000 [Mid America Flight Museum]""1928 Curtiss-Wright Travel Air 4000 C/N 416" construction number 475, registration NC2709 (current in 2024"Aircraft Inquiry" ) at the Kelch Aviation Museum, Brodhead, Wisconsin"1927 Travel Air 4000" construction number 766, registration NC6425 (current in 2024"Aircraft Inquiry" ), in the collection of the Cavanaugh Flight Museum in Addison, Texas"Aircraft" (closed indefinitely from January 1, 2024Sullivan 2024) construction number 850, registration NC9049 (current in 2024"Aircraft Inquiry" ) at the Western Antique Aeroplane & Automobile Museum, Hood River, Oregon"Travel Air 4000 [Western Antique Aeroplane & Automobile Museum]" construction number 1059, registration N9872 (current in 2024"Aircraft Inquiry" ). As of 2022, this was the oldest aircraft regularly tracked by flight tracking service Flightradar24.Leigh, 2022 construction number 1151, registration CF-JLW (current in 2024"CCAR - Aircraft Details") at the Reynolds Museum, Wetaskiwin, CanadaSkaarup 2009, p. 450 construction number 1224, registration NC648H (current in 2024"Aircraft Inquiry" [648H]) at EAA Aviation Museum, Oshkosh, Wisconsin"1929 Travel Air E-4000 - NC648H" construction number 1266, registration NR671H (current in 2024"Aircraft Inquiry" [671H]) in the collection of The Ninety-Nines Museum of Women Pilots."Louise Thaden's Travel Air" As of 2024, on loan to the Kansas Aviation Museum, Wichita, Kansas"Indoor Exhibits" construction number 1295, registration NC367M (current in 2024"Aircraft Inquiry" [367M]) at Beechcraft Heritage Museum, Tullahoma, Tennessee"Parish Travel Air" construction number 1340, registration NC434N at the National Air and Space Museum, Washington, D.C. construction number 1365, registration NC174V (current in 2024"Aircraft Inquiry" [174V]) at Fantasy of Flight, Polk City, Florida"1929 Travel Air 4000" construction number 1379, registration NC477N (current in 2024"Aircraft Inquiry" [477N]) at Owls Head Transportation Museum, Owls Head, Maine"1930 Curtiss-Wright Travel Air D-4000 Speedwing"
Specifications (E-4000)
Notes References
Bibliography