33 Things You Probably Don’t Know About the CH-47 Chinook

The twin-engine, tandem-rotor CH-47 Chinook helicopter is one of the world’s most iconic and recognizable military aircraft. But here are some things you may not know about the granddaddy of all heavy-lift helicopters:

1. Like several other U.S. Army helicopters, the Chinook takes its name from Native American culture and, specifically, the Chinookan People of the Northwestern United States.
2. The CH-47 was designed to replace the Sikorsky CH-37 Mojave, which was retired from the Army’s fleet in the late 1960s.
3. Veritol Aircraft Corporation, the original developer of the CH-47, was acquired by Boeing in 1960.
4. The new helicopter was originally designated the Vertol Model 107 or V-107.
5. Development work on the CH-47 began in 1958 and the Chinook took its first flight in 1961.
6. That flight – and every other one since – has been powered by a pair of Honeywell T55 engines.
7. The “CH” stands for “Cargo Helicopter.”
8. Originally fielded in the Vietnam War, the CH-47 has undergone a series of upgrades to increase lift and airworthiness in combat environments.
9. Designed to carry about 36 passengers, one Chinook is reported to have carried 147 refugees in a single lift in the waning days of the Vietnam War.  
10. The CH-47 was one of the first two helicopters powered by a turbine engine. The other was the UH-1 Huey.
11. The first fully-equipped Army Chinook, designated the CH-47A, entered service in August 1962 with a gross weight of 33,000 pounds.
12. The Chinook is the U.S. Army’s only heavy-lift cargo helicopter supporting combat and other missions.
13. Secondary missions include medical evacuation, search and rescue, parachute drops, disaster relief and aircraft recovery. 
14. The CH-47 is considered the “workhorse” of the U.S. Army helicopter fleet.
15. The Chinook has several means of loading cargo including multiple doors across the fuselage, a wide loading ramp located at the rear of the fuselage and three external hooks to carry underslung loads.
16. The Chinook's ability to carry large, underslung loads has been of significant value during natural disaster and humanitarian relief missions.
17. The CH-47 can lift close to 48,000 pounds at 4,000 feet and 95 degrees F.
18. The helicopter flies with a minimum crew of three – pilot, copilot and flight engineer.
19. Honeywell T55 engines have more than 12 million hours of operation under their belts.
20. The CH-47F is considered the world's fastest military helicopter with a maximum speed of 315 km/hr (196 mph).
21. The latest version of the T55 engine – Honeywell’s next-generation T55-714C – generates 6,000 shaft-horsepower at sea level compared to just 2,050 for the original T55.
22. The Chinook is one of only two military aircraft developed in the 1960s still in production and service after 50 years – the other is the C-130.
23. Twenty-two countries currently fly the CH-47 Chinook. The U.S. Army and U.K. Royal Air Force are the two largest operators.
24. The CH-47F upgrade program included the installation of a new digital cockpit and modifications to the airframe to reduce vibration. 
25. Boeing and Honeywell developed an advanced digital cockpit equipped with multifunction liquid crystal displays and electronic flight instruments.
26. The Chinook is capable of balancing on its two rear wheels, on the edge of a cliff for example, while still hovering in a maneuver called a pinnacle landing.
27. Empty, the CH-47F Chinook weighs 26,800 pounds.
28. The MH-47 is a special-operations version of the Chinook.
29. The Chinook has a mission radius of 200 miles.
30. A commercial model of the Chinook, the Boeing-Vertol Model 234, is used worldwide for logging, construction, fighting forest fires and supporting petroleum-extraction operations.
31. The newest version of Honeywell’s powerful, efficient T55 engine is currently being evaluated by the Army to demonstrate its capabilities.
32. The new T55-714C engine offers 25% better reliability, carries a 22% heavier payload and provides an 8% improvement in fuel efficiency.
33. It’s available as a new-production engine or as an upgrade for the T55-714A engine that now equips most of the world’s C-47 Chinook fleet.