The glider was designed by the Waco Aircraft Company. Flight testing began in May 1942. More than 13,900 CG-4As were eventually delivered.
Design and development
The CG-4A was constructed of fabric-covered wood and metal and was crewed by a pilot and copilot. It had two fixed mainwheels and a tailwheel.
The CG-4A could carry 13 troops and their equipment. Cargo loads could be a 1⁄4-ton truck (i.e. a Jeep), a 75 mm howitzer, or a 1⁄4-ton trailer, loaded through the upward-hinged nose section. Douglas C-47 Skytrains were usually used as tow aircraft. A few Curtiss C-46 Commando tugs were used during and after the Operation Plunder crossing of the Rhine in March 1945.
The USAAF CG-4A tow line was 11⁄16 inch (17 mm) nylon, 350 feet (110 m) long. The CG-4A pickup line was 15⁄16 inch (24 mm) diameter nylon, but only 225 ft (69 m) long including the doubled loop.
In an effort to identify areas where strategic materials could be reduced, a single XCG-4B was built at the Timm Aircraft Corporation using wood for the main structure.[3]
Production
From 1942 to 1945, the Ford Motor Company's "Iron Mountain Plant" in Kingsford, Michigan, built 4190 units of Model CG-4A gliders for use in combat operations during World War II. The Kingsford plant built more CG-4A gliders than any other company in the nation at much less cost than other manufacturers.
The 16 companies that were prime contractors for manufacturing the CG-4A were:
The factories ran 24-hour shifts to build the gliders. One night-shift worker in the Wicks Aircraft Company factory in Kansas City wrote,
On one side of the huge bricked-in room is a fan running, on the other a cascade of water to keep the air from becoming too saturated with paint. The men man the paint sprayers covering the huge wings of the glider with the Khaki or Blue and finishing it off with that thrilling white star enclosed in a blue circle that is winging its way around the world for victory ...
The wings are first covered with a canvas fabric stretched on like wallpaper over plywood then every seam, hold, open place, closed place, and edge is taped down with the all adhesive dope that not only makes the wings airtight, but covers my hands, my slacks, my eyebrows, my hair, and my tools with a fast-drying coat that peels off like nail polish or rubs off with a thinner that burns like Hell.[10]
Operational history
During Operation Market-Garden, Waco gliders are lined up on an English airfield in preparation for the next lift to the Netherlands.German troops examine an abandoned Waco, Normandy, June 1944
CG-4As went into operation in July 1943 during the Allied invasion of Sicily. They were flown 450 miles across the Mediterranean from North Africa for the night-time assaults such as Operation Ladbroke. Inexperience and poor conditions contributed to the heavy losses. They participated in the American airborne landings in Normandy on 6 June 1944, and in other important airborne operations in Europe and in the China Burma India Theater. Although not the intention of the Army Air Forces, gliders were generally considered expendable by high-ranking European theater officers and combat personnel and were abandoned or destroyed after landing. While equipment and methods for extracting flyable gliders were developed and delivered to Europe, half of that equipment was rendered unavailable by certain higher-ranked officers.[citation needed] Despite this lack of support for the recovery system, several gliders were recovered from Normandy and even more from Operation Market Garden in the Netherlands and Wesel, Germany.
The CG-4A found favor where its small size was a benefit. The larger British Airspeed Horsa could carry more troopers (seating for 28 or a jeep or an anti-tank gun), and the British General Aircraft Hamilcar could carry 7 tons (enough for a light tank), but the CG-4A could land in smaller spaces. In addition, by using a fairly simple grapple system, an in-flight C-47 equipped with a tail hook and rope braking drum could "pick up" a CG-4A waiting on the ground.[11] The system was used in the 1945 high-elevation rescue of the survivors of the Gremlin Special 1945 crash, in a mountain valley of New Guinea.[12]
After World War II ended, most of the remaining CG-4As were declared surplus and almost all were sold. Many were bought for the wood in the large shipping boxes. Others were bought for conversion to towed camping homes with the wing and tail end cut off and being towed by the rear section and others sold for hunting cabins and lake side vacation cabins.
The last known use of the CG-4A was in the early 1950s by the USAF with an Arctic detachment aiding scientific research. The CG-4As were used for getting personnel down to, and up from, floating ice floes, with the glider being towed out, released for landing, and then picked up later by the same type of aircraft, using the hook and line method developed during World War II. The only modification to the CG-4A was the fitting of wide skis in place of the landing gear for landing on the Arctic ice floes.[13]
Variants
The XPG-1 prototypeThe XPG-2 prototypeA 3-view line drawing of the PG-2A
XCG-4
Prototypes, two built, plus one stress test article
CG-4A
Main production variant, survivors became G-4A in 1948, 13,903 built by 16 contractors
1 August 1943: CG-4A-RO 42-78839, built by contractor Robertson Aircraft Corporation,[15] lost its right wing and plummeted to earth immediately after release by a tow airplane over Lambert Field, St. Louis, Missouri, USA. Several thousand spectators had gathered for the first public demonstration of the St. Louis-built glider, which was flown by 2 USAAF crewmen and carried St. Louis mayor William D. Becker, Robertson Aircraft co-founder Maj. William B. Robertson, and 6 other VIP passengers; all 10 occupants perished in the crash.[16] The accident was attributed to the failure of a defective wing strut fitting that had been provided by a subcontractor; the post-crash investigation indicted Robertson Aircraft for lax quality control; several inspectors were relieved of duty.[15]
WACO CG-4A 3-view drawingPage from manual specifying loads: as well as being able to carry up to 13 airborne troops or 6 litters of wounded men, the CG-4 could also carry such loads as a field kitchen, an anti-tank gun, a weather station, radar or radio equipment, a repair shop, a howitzer, a photographic laboratory, or a quarter-ton truck.
Data fromAviation Enthusiasts Corner.[43] and Pilot's Flight Operating Instructions for Army Model CG4A Glider (TO No. 09-40CA-1)[44]
General characteristics
Crew: two pilots
Capacity: 13 troops, or quarter-ton truck (Jeep) and 4 troopers, or 6 litters and 4,197 pounds (1,904 kg) useful load[45]
Length: 48 ft 8 in (14.8 m)
Wingspan: 83 ft 8 in (25.5 m)
Height: 15 ft 4 in (4.7 m)
Wing area: 900 sq ft (83.6 m2)
Empty weight: 3,900 lb (1,769 kg)
Gross weight: 7,500 lb (3,402 kg)
Max takeoff weight: 7,500 lb (3,402 kg)
Max take off (Emergency Load): 9,000 pounds (4,100 kg)
Performance
Maximum speed: 150 mph (240 km/h, 130 kn) CAS[N 1] at 7,500 pounds (3,400 kg)
128 mph (206 km/h) CAS/135 mph (217 km/h) IAS at 9,000 pounds (4,100 kg)
Rate of sink: About 400 ft/min (2 m/s) at tactical glide speed (IAS 60 mph; 97 km/h)
Landing run: 600–800 feet (180–240 m) for normal three-point landing; "Landing rolls of approximately 2,000 to 3,000 feet (610 to 910 m) are to be expected at the higher emergency gross weights..."
^Bednarek, Janet Rose Daly and Michael H. Bednarek. Dreams of Flight: General Aviation in the United States. 1,074 by Charles Day - "Silent Ones Clinton County Army Air Field"
AAF Manual No. 50-17, Pilot Training Manual for the CG-4A Glider. US Government, 1945, select pages available on Wikimedia Commons, Category:Waco CG-4.
AAF TO NO. 09-40CA-1, Pilot's Flight Operating Instructions for Army Model CG-4A Glider, British Model Hadrian.US Government, 1944, available on Wikimedia Commons, Category:Waco CG-4.
Andrade, John M. U.S. Military Aircraft Designations and Serials since 1909. Earl Shilton, Leister, UK: Midland Counties Publications, 1979. ISBN0-904597-22-9.
Diehl, Alan E., PhD. Silent Knights: Blowing the Whistle on Military Accidents and Their Cover-ups. Dulles, Virginia: Brassey's, Inc., 2002. ISBN1-57488-412-3.
Fitzsimons, Bernard, ed. "Waco CG-4A." Illustrated Encyclopedia of 20th Century Weapons and Warfare, Volume 11. London: Phoebus, 1978. ISBN978-0-241-10864-2.
Gero, David B. Military Aviation Disasters: Significant Losses Since 1908. Sparkford, Yoevil, Somerset, UK: Haynes Publishing, 2010, ISBN978-1-84425-645-7.
Masters, Charles J., Glidermen of Neptune: The American D-Day Glider Attack Carbondale, Illinois: Southern Illinois University Press, 1995. ISBN978-0-809-32008-0.
Soukup, Oldřich (1979). "Kluzáky Československého Vojenského Letectva (I.)" [Czechoslavak Military Gliders (I.)]. Letectví a Kosmonautika (in Czech). Vol. 55, no. 18. pp. 693–695.
