Laister-Kauffman TG-4

The Laister-Kauffman TG-4 (designated LK-10 Yankee Doodle 2 by its designer) was a sailplane produced in the United States during the Second World War for training cargo glider pilots. It was a conventional sailplane design with a fuselage of steel tube construction and wooden wings and tail, skinned all over in fabric. The pilot and instructor sat in tandem under a long canopy.

Design and development

Jack Laister designed the aircraft in response to the formation of the United States Army Air Corps' American Glider Program in 1941, basing it on his Yankee Doodle design of 1938 for Lawrence Tech. Aside from the addition of a second seat, the Yankee Doodle 2 differed from it predecessor in having wings of constant dihedral instead of gull wings. The USAAC expressed interest, but only if Laister could arrange for the manufacture of the type. When Laister found a sponsor in businessman John Kauffman, they established the Laister-Kauffman Corporation in St Louis, Missouri and the USAAC ordered three prototypes as the XTG-4.

When evaluation of the type proved positive, the Army placed an order for 75 aircraft, followed by an order for another 75. These were operated as the TG-4A, along with the original, single-seat Yankee Doodle that was impressed into service. All had been withdrawn from service prior to the end of the war when it was discovered that the flight characteristics of the aircraft were so different to those of a cargo glider, that the experience gained on the TG-4 was not particularly relevant.

Variants

• XTG-4 - prototypes (3 built)
• TG-4A - production model (150 built)
• TG-4B - civilian aircraft impressed into service (1 impressed)

Operators

LK-10 Serial #106 under prefix PT-PAZ operated by Aeroclube de Bauru in Brazil as of April 2013 ^[1]

Laister-Kauffman TG-4 PT-PAZ in Bauru, Brazil

Video of LK-10aflying at SOSA Gliding Club during the summer of 2013 - her 70th anniversary.

Aircraft on display

• Air Mobility Command Museum
• Museum of Aviation
• National Museum of the United States Air Force
• Planes of Fame
• Silent Wings Museum
• US Southwest Soaring Museum^[2]

Aircraft Under Restoration to Flight

TG-4A Serial #74 Under Restoration at Legend Of Aces Aviation (www.Legendofaces.com)

Specifications (LK-10 / TG-4A)

Data from The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II^[3]

General characteristics

• Crew: 1
• Length: 6.5 m (21 ft 4 in)
• Wingspan: 15.24 m (50 ft 0 in)
• Height: 1.115 m (3 ft 8 in) at cockpit
• Wing area: 15.2 m² (164 sq ft)
• Aspect ratio: 15.1
• Airfoil: root – NACA 4418, tip – NACA 4409
• Empty weight: 216 kg (476 lb) equipped
• Gross weight: 397 kg (875 lb)

Performance

• Stall speed: 61 km/h (38 mph; 33 kn)
• Never exceed speed: 203 km/h (126 mph; 110 kn)
  
• Rough air speed max: 203 km/h (126.1 mph; 109.6 kn)
• Aerotow speed: 203 km/h (126.1 mph; 109.6 kn)
• Winch launch speed: 130 km/h (80.8 mph; 70.2 kn)
• g limits: +6 -3 at 225 km/h (139.8 mph; 121.5 kn)
• Maximum glide ratio: 22 at 80 km/h (49.7 mph; 43.2 kn)
• Rate of sink: 0.97 m/s (191 ft/min) at 73 km/h (45.4 mph; 39.4 kn)
• Wing loading: 26.5 kg/m² (5.4 lb/sq ft)

See also

Aircraft of comparable role, configuration and era

DFS Kranich

Related lists

List of gliders

Notes

References

Further reading

• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 563. 
• Salmi, Reino J. (March 1943). "Gliders for Victory". The Wisconsin Engineer 47 (6): 8–9. Retrieved 2008-09-16.  (uncorrected OCR)

External links

• National Museum of the United States Air Force fact sheet
• Sailplane Directory entry on the LK-10
• LTU timeline
• Air Mobility Command museum
• Aircraft/laister-kauffman_tg-4a.htm Museum of Aviation
• The Air Mobility Command Museum