6 Ways We’ve Made the Chinook’s T55 Engine Better than Ever

A helicopter as iconic as the CH-47 Chinook deserves engines that are as powerful and reliable as the legendary heavy-lift champion itself. That’s why generations of Honeywell engineers have made it their mission to continuously improve our T55 engines, a pair of which have been powering every Chinook since its first flight in 1961.

The T55-714C engines we’re building today at our T55 Engine Center of Excellence in Phoenix share DNA with the original engine introduced in the 1950s, but that’s where the resemblance ends. We’ve made enormous strides in recent years to improve the engine’s performance, reliability and efficiency, making the 714-Charlie version of the T55 the best we’ve ever produced.

Available as a new-production engine or as a modification to the T55-714A engines flying on most of the world’s fleet of more than 900 Chinooks, the T55-714C represents an enormous leap forward for the T55 engine family. 

Here are six ways we’ve improved the T55-714C engine:

1. More Power for Lifting. The new T55-714C variant delivers the power the Chinook needs to perform its heavy-lift mission for the U.S. Army, National Guard, U.K. Royal Air Force, Royal Netherlands Air Force and others. The new engine generates nearly 6,000 shaft-horsepower at sea level compared to 4,777 for the 714A version and just 2,050 for the original T55. More horsepower means the Chinook can carry a 16% heavier payload of up to 21,000 pounds.
2. Greater Fuel Efficiency. Our focus on meeting fuel efficiency goals paid off with an 8% improvement in fuel consumption, which means the Chinook can fly farther, faster or lift more to accomplish its critical missions. Lower fuel burn also reduces operating costs and logistics requirements for Chinook fleets. 
3. More Rugged and Reliable. Chinook helicopters need to be ready to perform under on the battlefield and under the most challenging conditions imaginable. So, we’ve worked hard to make the T55-714C tough, rugged, reliable and easy to maintain. We’ve achieved a 25% overall improvement in reliability. 
4. Easier to Maintain. The new T55-714C is easier to service and maintain than previous versions of the engine. We responded to customer feedback and removed a major pain point for maintenance techs by repositioning the hydromechanical assembly (HMA) so that it’s no longer necessary to remove the engine to replace the HMA. We also reduced part count by 27%. Mean repair time is down 28%, which improves aircraft availability. 
5. Better High, Hot and Heavy Performance. Our new engine is designed to perform when the going gets tough. The T55-714C delivers double the operating range for high, hot and heavy missions for more carrying power when operators need it most. We’ve also made the engine more sand tolerant, for improved reliability in desert operations. 
6. More Affordable. Upgrading from the T55-714A to the better-performing, more economical T55-714C costs 50% less than other upgrade options for the Chinook if done at overhaul intervals. The new engine is a drop-in replacement for the previous version and requires very minor aircraft changes - the same intake, exhaust and engine airframe mounts are used.

Honeywell has produced more than 6,000 engines in the T55 family since the first one rolled off our assembly line close to 65 years ago. They’ve logged about 12 million hours of reliable operation, most spent helping military Chinook operators achieve their heavy-lift missions, which can range from moving cargo and equipment on the battlefield, to transporting troops, to delivering critical supplies on humanitarian missions.

With the T55-714C we’ve developed a next-generation version of this proven engine that can enhance the capabilities and extend the service life of one of the most iconic helicopters in the fleet. We’re now working with the Army to demonstrate the new engine’s capabilities under real-world conditions.