Kenyon Joins Brookings Panel on Future Defense Technology

Wednesday, August 4, 2015

The Center for 21st Century Security and Intelligence at Brookings hosted a discussion on July 31 on the next defense technology revolution and how it will shape the future of the force, with a particular focus on 3-D printing.

Panelists included Brennan Hogan of LMI, Jim Joyce from Deloitte Consulting LLP, James Kenyon of Pratt & Whitney, and Dave Logan of BAE Systems Inc. Michael O'Hanlon of the Center for 21st Century Security and Intelligence moderated the discussion.

The full text of Kenyon's prepared remarks appears below.

Click here to watch a video of the panel discussion on C-SPAN.

Brookings Institute | Center for 21st Century Security and Intelligence

Panel Discussion on the Next Defense Technology Revolution

Remarks by Jimmy Kenyon, director, Advanced Programs & Technology, Pratt & Whitney

In 2012 the administration released what was then a new defense strategy, calling for, among other things, a more flexible, agile and technology-advanced force. Many of the technologies and technological advancements mentioned so far are reflective of this strategy. We see a very similar direction in military aerospace and propulsion.

Since early in the 20th century air power has been a hallmark of U.S. military strategy and power projection. A key part of this has been the propulsion system since, historically, generational leaps in military aviation tend to be tied to revolutions in propulsion. We are at the cusp of another revolution with the introduction of adaptive engines.

What do I mean by "adaptive engines," exactly? Let me offer this timely analogy.

For anyone who tuned in to watch Le Tour de France last week, you would have seen cyclists trying to get the most from their bicycles across 21 different race stages – over flat, hilly, and mountainous terrain – and over a distance of 3,360 kilometers. All of them share the ultimate goal of being the first to arrive to their "target location" – the finish line. In order to successfully power through differing stages, the cyclists would have to "adapt" their platforms – or change gears, so to speak – to perform in the most efficient way, no matter the requiring demands of the "terrain envelope."

Today, Pratt & Whitney is partnered with the U.S. Air Force on the Adaptive Engine Technology Development, or AETD, program, which seeks to mature a three-stream, adaptive engine design that allows optimization of engine performance throughout the flight envelope.

Traditional jet engines use two streams of air, one in the center or engine core to drive the engine itself and another bypass stream to produce thrust, and operate as single-point designs. They are designed to meet the most stressing mission requirements but take a penalty, usually in terms of efficiency, when operating off design. This can be a big deal in a tactical military aircraft that operates across multiple speeds and altitudes across the flight envelope.

The AETD concept uses a third stream of air that can be modulated to effectively change the operating point of the engine to match flight conditions throughout the flight envelope, thereby increasing the overall efficiency of the engine and aircraft and allowing reduced fuel burn, increased range, or increased time on station.

It's kind of like (the tactical fighter equivalent of) having a hybrid of the coolest, most tricked out BMX bike, but with all the best attributes of the world's highest performance racing bike to boot.

Adaptive engines aren't entirely new. Pratt & Whitney invented the very first adaptive engine in 1958, the J58, which powered the SR-71 Blackbird to incredible sustained flight speeds above Mach 3. More recently, the F135 propulsion system that powers the F-35 Joint Strike Fighter is adaptive, as it transitions between conventional flight and short takeoff / vertical landing, or STOVL, operations. This transition introduces profound changes in the engine cycle while in flight, which the propulsion system seamlessly accommodates.

AETD is different in that it is intended to vary the engine cycle continuously throughout the flight envelope, with a focus on improving overall mission capability such as range or persistence through increased efficiency.

Pratt & Whitney's AETD design is progressing well. We're projected to meet all design requirements, including performance and product cost targets, and have key tests planned next year. In addition, we are working with the Air Force toward the Adaptive Engine Transition Program, or AETP, an investment of nearly $2 billion with Pratt & Whitney and GE that will progress our designs toward future applications – the platforms that will follow the F-22 and F-35.

When you are pushing the boundaries of new technologies, such as we have on the F135 and AETD programs, you have to overcome some challenges along the way. Things like …

  • Architecture and design trade-offs; for AETD we had the unique challenge of finding the best performance in a configuration that was largely defined through the specific requirement for a 3-stream engine
  • Using the right manufacturing tools; the AETD design introduced a need for innovation in how we make some of the components; we also look for opportunities to understand approaches such as additive manufacturing and the challenges associated with them in aerospace applications such as engines
  • Using advanced materials, coatings, ceramics and metallic alloys that can withstand high-temperatures; AETD really pushes the envelope on temperatures
  • • Not to mention the constraints that come from limited government funding, or perhaps from some government acquisition policies and practices.

Notwithstanding some of these challenges, we arrived at an innovative approach to introduce a third stream to the engine that is simple, but provides outstanding control of the engine's operation throughout the flight envelope.

It's really an exciting time at Pratt & Whitney. Not only are we powering the introduction of the world's most advanced (and adaptive) fighter engine with the Marines now declaring operational capability of the F-35B, but we're also reinventing adaptive engines for the next generation of fighter aircraft.