Patricia Stevens
United States of America
From Leadership Profile: Vertiflite Winter 2011
Dr. Patricia Stevens, Chief Technology Integrator, Boeing Advanced Mobility
Within the Phantom Works group of Boeing Advanced Mobility, Dr. Patricia Stevens looks for Science and Technology (S&T) to advance both rotary and fixed-wing aircraft. Her current product portfolio includes technologies for the CH-47 helicopter, V-22 tilt rotor, C-17 jet transport, and KC-46 jet tanker and it extends to vertical lift platforms of the future. Dr. Stevens explains, “The mission of Phantom Works is to identify and develop technologies for transition onto our current platforms. It is also equally important to cultivate opportunities for the capture and development of new programs. My job has one foot in business development and one foot in engineering. My role is to identify critical technologies and to develop strategies to fund, develop, and transition those technologies to gain advantage for our products.”
The advantage to this approach may be better performance. Boeing will demonstrate a 12 ft diameter DiscRotor in its Philadelphia wind tunnel for DARPA later this year and the company has bid on Phase II Mission Adaptive Rotor work aimed at high-speed helicopters and tilt rotors. Dr. Stevens notes, “When you look at the future of rotorcraft, there’s a lot more talk about speed and range as an important requirement in vertical lift. Tilt rotor technology today, with very little investment, is a scalable solution to meet the speed and range requirements.” Likewise, a competitive advantage would be lessened manufacturing and operating costs. “I’m in love with the technologies that improve our performance,” says Dr. Stevens, “but unless we can solve the affordability challenge, there won’t be the funds available to insert the next generation of technologies.”
Raised in Newark Delaware, Patricia Stevens earned a bachelor’s degree in mechanical engineering from Penn State and immediately went to work on post-graduate studies. “My father is a chemical engineer,” she notes. “He worked for DuPont leading a group that did all sorts of environmental engineering, including noise and vibration control. I became fascinated with the concept of noise and vibration control. As part of my Master’s degree, I designed a semi-active vibration control. It was essentially a vibration absorber that varied frequency, so if the vibration changed frequency, it would cancel it out.”
The academic exercise took a practical turn at Boeing. Dr. Stevens recalls, “My resume with my Masters topic landed on the desk of a Technical Fellow here in Philadelphia who had just kicked off an internally funded research and development project looking at developing a semi-active vibration controller for the Chinook. That concept at a top level was very similar to what I had done my Masters project on.” Helicopters also held special appeal. “I was very balanced between my interest in fluid dynamics, mechanical structures, and dynamics analysis, which oriented itself very well to a career in helicopter design, so the technical interest was definitely there. I didn’t have a pilot or any military service people in my family, but I very much enjoyed the technical challenges. When I got to know the rotorcraft industry through the people working on the vibration control project, my fascination grew from there.”
The new Boeing engineer was assigned to Independent Research and Development projects, mostly in vehicle management systems. Dr. Stevens remembers, “I did indeed get to spend about two years with the team working on the vibration absorbers for the Chinook. I also spent a great amount of time working in the area of Health and Usage Monitoring Systems – this was in the early ‘nineties when HUMS were first beginning to show their potential for reducing maintenance costs and improving safety on our platforms.”
After five years at Boeing, Patricia Stevens returned to Penn State full-time to pursue a doctorate with research in Condition Based Maintenance. Graduation pointed her again to Boeing. “We were right at the height of the Comanche program. One of my earlier career mentors, Steve Glusman, set me up in an interview with the woman who ran the Mission Equipment Package for Comanche. The big challenges at that time were in the areas of sensors and fire control and getting the integrated system to work while you’re flying around in a flexible airframe. Essentially it became a dynamics and vibration problem.”
Comanche technical achievements remain proprietary, but with the cancellation of the Army scout-attack helicopter in 2004, Dr. Stevens took a functional role at what was then Boeing Army Systems. “It was at the height of network-centric operations in the Army,” she explains, “and my job was supporting the chief engineer for that business unit. I was working the technology road mapping/technology plans for Army systems. I took inputs from the FCS [Future Combat Systems] program, the Apache program, the Chinook program, the JTRS [Joint Tactical Radio System] program. We pulled them together to understand from a business unit level, ‘where do we make our investments?’”
The assignment had important implications for a technologist turning manager. Dr. Stevens says, “I learned about the long-range business plan in that job. I think most people in this business, at whatever level, love the technology and want to support our service people, but the realities of the business are we need to put together a long-range business plan that’s going to close. That was when I started to really develop and mature my views of technology: What’s a good technology look like? How do you manage the push-and-pull between the programs pulling for a technology to meet a gap versus the technologists selling it to somebody in the business development community?”
Phantom Works and Helicopters
In August 2005, when Boeing again reorganized to establish a Rotorcraft Division, Dr. Stevens moved to Boeing Advanced Systems – now the Phantom Works – looking for ways to protect ground vehicles from Improvised Explosive Devices (IEDs). She ultimately refocused on rotorcraft, managing the DARPA DiscRotor and supporting the DARPA Mission Adaptive Rotor programs. “The DiscRotor program is designed to achieve high-speed flight while maintaining the vertical takeoff and landing capability of a helicopter. If you could design a compound helicopter so that when you get to forward flight the wing provides all of the needed lift, then you could retract the blades and get them out of the way to reduce drag. Although it sounds logical, there are some real challenges with that. When the rotor is spinning at full rpm, the centrifugal forces (CF) are very large. In order to build a telescoping blade, sections of the blade need to be essentially hollow. That’s not how we build our blades today, so significant questions would need to be addressed: How do we handle all of the loads? How do we build an actuator and a mechanism with enough force to overcome the CF of the rotating system? How do you overcome the twisting of the blade under aerodynamic loads so you don’t get binding as you retract the blade? And once you do that, what are the aerodynamic properties of a blade that’s designed to have that mechanism internal to the blade structure?”
Under two DARPA contracts, a Boeing team and a separate Bell-Boeing tilt rotor team provided Phase I trade studies, conceptual designs, and system requirements for edgewise and tilt rotor Mission Adaptive Rotor (MAR) systems. “The vision of the MAR is that the pilot could essentially pick a mission and adapt the rotor system to maximize the performance during mission segments such as cruise and hover. If you’re in a high-hot condition and you need all the thrust you can get to take off, you may choose to adapt the rotor, say with high blade twist, to maximize takeoff performance. There may be another part of your flight where you’re looking for maximum range or maximum endurance. Well, instead of carrying with you a system optimized for most efficient hover, alter the rotor system -- possibly the length or the twist of the rotor blades -- so you have the most efficient cruise.”
Boeing Phantom Works is also behind the stealthy Phantom Ray and long-endurance Phantom Eye fixed-wing unmanned aircraft. “There is a tie-in between rapid prototyping development and X-planes,” observes Dr. Stevens, “There’s nothing like having data from flying platforms to help improve and calibrate our toolset. She admits, “We don’t currently have a rotary wing demonstrator, but we always have a commitment to rapid prototyping. We are working with our president Darryl Davis to identify the next Boeing rapid prototyping project.”
Phantom Works also pursues near-term technologies such as the split-torque transmission in the Block III Apache Longbow. According to Dr. Stevens, “The role of our organization has evolved over time, striking the balance between developing advanced technologies versus advanced programs.” The group also bridges the latest Boeing reorganization. Boeing Advanced Mobility includes rotary and fixed-wing products. “There are a number of underlying technologies where there are some real synergies,” says Dr. Stevens. “For instance, one of our rotorcraft customers’ gaps is systems that will allow them to perform in a Degraded Visual Environment. One of our Advanced Airlift/Tanker gaps is the ability to land in austere environments on unimproved runways with poor visibility. The people working those technologies were working together for years before we became Advanced Mobility.”
Though Boeing split rotorcraft between its Mobility and Global Strike businesses, Dr. Stevens still chairs the Boeing Rotorcraft Technology Strategy Team representing Mesa and Philadelphia. “We kept that synergy,” she notes. “Apache has their business commitments. Chinook has their business commitments. But from a technology perspective, we kept our rotorcraft technology strategy team whole. As we look at Science and Technology development, understanding what S&T contracts to pursue and how to pursue them, we keep those groups working together. It has been a natural working relationship.”
Small businesses also contribute to the rotorcraft improvements. “We’ve been able to get significant value out of the SBIR programs,” says Dr. Stevens. “Boeing as a whole has acknowledged we can’t afford to develop everything here so Boeing, at high levels and within specific programs, looks at who can we partner with on specific technologies to make our products better. We’re working with several companies for drivetrain improvements on the Chinook. On the V-22, we’re working with a company that has really interesting survivability technologies.”
Dr. Stevens is the Boeing representative to the National Rotorcraft Technology Center/Vertical Lift Consortium’s Technical Advisory Sub-Council and acknowledges the myriad of challenges facing industry. She says, “One of my greatest concerns in the rotorcraft industry is that it’s been so long since we had a new-build rotary-wing aircraft that the people who know how to start from a blank sheet of paper and come up with something that flies are nearing retirement. We’re also concerned about the cost of developing new technologies. I think that’s one of the reasons why Phantom Works has invested heavily in several rapid prototyping projects. It helps us to reinforce our skills in our workforce and apply those skills to the design of something. In a rapid prototyping environment, you can see it from a blank sheet of paper to flight over just a couple of years and we can use that prototyping environment to drive down technical risk and the cost of development programs.”
Boeing works closely with Penn State, the University of Maryland, and Georgia Tech, and other universities to incubate rotorcraft technology and engineering talent. Dr. Stevens observes, “I have to say I’ve been working with several of our newer hires, and I’m amazed at their skill levels. They’re incredibly talented individuals. They’re mature. They have a work ethic, and they really know their fields. It has helped us a lot in rotorcraft that the Army, Navy, and NASA have continued to support the Vertical Lift Rotorcraft Centers of Excellence (VLRCOEs). They’re developing engineers who know how rotorcraft work and who are passionate about the rotorcraft industry.”
Dr. Stevens also acknowledges the importance of mentoring relationships. “There was a period of my career when John Tracy, our chief technical officer, reached out to me and met with me in a mentoring capacity. I’m not the only one he’s reached out to. He takes the time to identify and develop individuals who he believes could make a big difference for Boeing. He is not alone – most of our leaders invest heavily in mentoring. It is very important and meaningful to have a company treat its people that way.”