The right nacelles and struts to extend the power of the B-52

Collins Aerospace is perfectly positioned to help keep the Stratofortress flying for decades


Image courtesy of

When you create something that becomes your go-to solution decade after decade, you keep innovating to ensure its longevity. Extending the life of Boeing’s B-52 bomber (originally built in the 1950s) so it can operate into the 2050s is a prime example of making what’s old new again. As part of overhauling this legendary aircraft, the United States Air Force (USAF) will re-engine the remaining 76 bombers with commercial off-the-shelf jet engines that are more efficient, more powerful and less expensive to operate as part of its Commercial Engine Replacement Program (CERP).

Well positioned for future success

Four different engines are under consideration for the B-52 modernization, which means other components of the propulsion system, such as nacelles and struts, also are needed. Selecting the right equipment combination falls to Boeing and the USAF as part of the re-engining initiative. No matter which engine is selected, the Aerostructures unit of Collins Aerospace is perfectly positioned to provide nacelles and struts after having produced 5,952 nacelles and 2,976 struts for all eight of the B-52 variants to date.

“Since our company first started manufacturing highly engineered structural components 80 years ago, we’ve supported more than 50 programs and our products have been certified on 19 aircraft programs in just the last 10 years,” said Marc Duvall, president, Aerostructures, Collins Aerospace. “And given that we’ve been part of the B-52 program since its inception in the 1950s, we understand how to efficiently and accurately manufacture nacelles and struts to meet the standards and schedules required by Boeing and the Air Force.”

The right experience at the right time

In fact, Collins has experience supplying nacelles to all three of the engine makers vying for the B-52’s upgrade, including direct experience on three of the four specific engine families under consideration: General Electric’s CF34-10 engine, Pratt & Whitney’s 800 engine series and Rolls Royce’s BR 715 engine (the precursor to the BR725 engine they’ve proposed for the B-52). This related experience, coupled with Collins’ decades of proven success with the B-52 and many other military and commercial programs since then, make the company an ideal candidate for the CERP.

Specifically, Collins designed and fabricated the nacelles now integrated with GE’s CF34-10 engine on Embraer’s 190 and 195 aircraft platforms. Additionally, Collins has direct experience developing nacelles for business-jet platforms equipped with the PW800 engine series. Even though the engines were the same on each platform, separate nacelles were designed and manufactured featuring unique shapes to best fit each aircraft’s aerodynamic structure. Finally, Collins has extensive experience with Rolls Royce’s BR715 engine on Boeing’s 717 aircraft, serving as the exclusive nacelle provider for that successful program.

Interestingly, although the B-52 Stratofortress weighs in at approximately 185,000 pounds and is more than 159 feet long and 40 feet high, all of the engine models under consideration to power it in the future were originally designed for business/regional-jet aircraft due to considerations for size and thrust. That’s because the giant airplane uses eight of the smaller engines in its unique, twin-pod nacelle that has become a hallmark of the B-52. By maintaining that existing design, the USAF can retain its weapons systems without having to repeat lengthy aerodynamic testing.

“No matter which engine is chosen for the B-52 CERP, our extensive experience in nacelle and strut manufacturing for this aircraft and many others makes us uniquely capable of supporting Boeing however needed as they implement the new engine-system components,” Duvall said.

A trusted member of the re-engining team

The B-52 nacelles will continue to be constructed of sheet metal to ensure ease of servicing and maintaining the fleet. Collins Aerospace understands the complexity of the uniquely contoured twin-pod nacelle and how to efficiently manufacture it with a high-degree of precision and quality.

In general, re-engine programs are not new to Collins. The company has supported the USAF with its two largest re-engining programs, the Lockheed C-5 Galaxy and Boeing KC-135 Stratotanker. The C-5M required more powerful and reliable engines and Collins was there to support the program by providing the inlet, fan cowl, core cowl and engine build up (EBU) components. Collins also designed and manufactured the new struts required for the C-5M. Likewise, for the KC-135, Collins manufactured the inlets and fan cowls for approximately 425 re-engine kits.

“When you look at our long history with the B-52 program, decades of experience manufacturing structural elements, existing relationship with Boeing and our proven track record of delivering high-quality products on time, we believe we offer the best solution at the lowest risk for helping the B-52 Stratofortress extend its power well into the future,” Duvall said.