UTC AEROSPACE SYSTEMS IS READY TO EXTEND THE B-52’s MISSION

This article was originally published on AviationWeek.com

The year was 1952. Rohr Aircraft Corporation was launching design and production of propulsion system components such as the nacelle, pylon, engine mount and other systems for Boeing’s cutting-edge new bomber: the B-52. The company knew it had a challenging project on its hands.

For one thing, the configuration of the propulsion system was unique. In an era when most aircraft were still propeller-driven, the B-52 was jet-powered – featuring eight 10,000-lb. thrust Pratt & Whitney J57-P-1W turbojet engines. Adding to the complexity, the configuration featured a unique twin-engine “pod” layout. This called for innovation. Specifically, it required the design of propulsion system components that would be easy to service in field conditions, while meeting the demanding performance requirements of Boeing, which had design authority and approval over the project.

Ultimately, the components Rohr developed for the B-52 in the early 1950s proved so capable that they still serve reliably on the iconic bomber to this day. Rohr – now UTC Aerospace Systems-Aerostructures – was up to the challenge then and today, more than six decades later, it remains uniquely capable of supporting the continuing evolution of the B-52.

Leveraging a legacy of experience

As the B-52 has advanced from the first “A” model up to the current “H” model, UTC Aerospace Systems has expanded on its innovations, adapting and modifying its initial component configurations to accommodate increased electrical power generation and engine thrust.
This adaptability is amply evident in the nacelle and pylon systems for the ducted fan power plant on today’s B-52H model. The B-52H features Pratt & Whitney TF33-P-3 turbofans, which offer 70% more thrust than the engines on the original B-52A.

Now, as the United States Air Force (USAF) moves forward with plans to modernize the B-52 with new engines, UTC Aerospace Systems is ready to leverage its deep experience in military aircraft re-engine programs. Augmented by six decades supplying advanced nacelle systems for new generations of military and commercial aircraft, UTC Aerospace Systems is the perfect choice to design and manufacture the primary propulsion system components for the Boeing B-52 life-extension program.

No stranger to military aircraft upgrades

The USAF has proposed this program for the B-52, currently in the feasibility study stage, to extend the life of the venerable Cold War platform to 2050. Part of the life-extension strategy – which is focused only on B-52H models – will be to replace the engines with upgraded units while still retaining the eight-engine configuration. This will likely require new pylon and nacelle systems, along with new engine mounts and new Engine Build-Up (EBU) external engine systems.

Who better than UTC Aerospace Systems to take on this task? Since participating in the design and manufacture of the original B-52 nacelle and pylon systems, UTC Aerospace Systems has produced a steady stream of primary propulsion system components for numerous platforms. In commercial aviation, these range from the Boeing 707 to the 787, and the Airbus A300 to the A350. In the military segment, the portfolio includes the Lockheed C-141, C-5 Galaxy, C-130 Hercules and P3 Orion.

UTC Aerospace Systems is also no stranger to military aircraft upgrades involving engine replacement. Just as it was ready with an innovative nacelle/pylon solution when the USAF re-engined the B-52, it also stepped up to the challenge when the USAF modernized its C-5 Galaxy military airlifter with new engines in the late 1990s. Starting in 2002, the company drew on its experience providing the nacelles and pylons for the original C-5 Galaxy to design and manufacture the new pylons required for the Lockheed C-5M Reliability Enhancement and Re-Engining Program (RERP). A key element of the C-5 upgrade program was replacing its General Electric TF-39 engines with more powerful and reliable GE CF6-80C2s. UTC Aerospace Systems also provided the re-engined C-5 with the existing inlet and fan cowl nacelle components it manufactures for the C2-powered Boeing 767. With continuous improvement in its DNA, UTC Aerospace Systems brought this mindset to the C-5M RERP, driving reduced cycle times and costs even as it delivered the final units.

Direct experience with the likely B-52 engine candidates

The three major aircraft engine manufacturers – Pratt & Whitney, Rolls Royce and GE – have suggested several possible engine candidates for the B-52 life extension program. These include the Rolls Royce BR725 engine (featured on the Gulfstream G-650), General Electric’s CF-34-10 engine (featured on the Embraer 190/195) and more recent Passport engine, and Pratt & Whitney’s PW800 (certified to power the Gulfstream G500/G600 and selected to power the new Dassault Falcon 6X). UTC Aerospace Systems already has direct experience with three of these engines.

Starting in 1997, UTC Aerospace Systems designed and manufactured the nacelle and thrust reverser for the Rolls Royce BR715 engine featured on the Boeing 717. The newer BR725 is derived from this BR715 engine. Two years later, the company launched the design and manufacturing of the nacelle, thrust reverser and exhaust system for the Embraer 190/195, which features the General Electric CF-34-10 engine. Additionally, UTC Aerospace Systems is currently developing an advanced nacelle for the Falcon 6X’s Pratt & Whitney PW812D engine. As a key contributor to these platforms, the business has gained an intimate familiarity with all three engines and stands ready to apply this expertise directly to the B-52 life-extension program. The program would fit seamlessly with UTC’s current production systems and commercial platform architectures.

Calling on its 78 years of relevant industry experience, 66 years as part of the B-52 program, as well as its direct, hands-on experience with the candidate engines, UTC Aerospace Systems offers the unique and precise capabilities needed to help extend the iconic bomber’s life for decades to come.


To learn more about our innovations for quieter, more efficient propulsion systems, please visit our Nacelle Systems page.