Planes of Future Past

On December 15, 2013, noted aerospace design engineer and author Dr. Daniel P. Raymer gave a talk “Planes of Future Past—Advanced Aircraft Designs at Rockwell, Lockheed, RAND and CRC” at a luncheon hosted by the Los Angeles-Las Vegas Section of the AIAA. The luncheon talk was supposed to have been the last AIAA event at The Proud Bird, which was facing closure due to a staggering rent increase. However, a large turnout (116 people) of AIAA members and guests were greeted with happy news: The Proud Bird had been granted a stay of execution in the form of a year extension of their lease, giving them time to negotiate more favorable terms.

In this celebratory setting, Raymer described his work on the X-31, F-22, F-35, and other projects. He treated the audience to an often humorous insider’s perspective on developing new aircraft that were faster and stealthier while being cheaper (but not always succeeding).

Raymer first worked as a project manager at North American Aviation (now Rockwell) in 1976, where he joined the Configuration Development group. He soon found out that his boss was the designer of the X-15 rocket plane! The group also included the designers of the space shuttle, the B-70, the B-1, the F-107, the F-108, and the HiMat.

Raymer’s first assignment was to modify a design created the year before by one of the head designers. He recalled “messing up the design really badly” but that the shop workers solved the problems, thus covering for him. Raymer then learned far more about lofting—a critical part of aircraft design.

One of Raymer’s next assignments was to design a Mach 3.5 Interceptor, meant simply to fly fast and fire missiles. The program manager wanted the missiles to resemble a flying saucer or Frisbee, which Raymer called the “world’s dumbest idea” but “you do what your PM says”. While the design approach was different, the aircraft was operationally similar to the first Lockheed concept for the F-22.

Raymer then described his experience on the “Innovative Strategic Aircraft Design Study” (ISADS). Boeing and Rockwell both received ISADS contracts. This was one of two proposals submitted by the project manager, who won both! Since that manager would be busy enough overseeing just one project, Raymer was made deputy project manager and chief engineer of the other project. After some time, he began receiving blank already-signed progress report forms to fill out as the other project manager came to trust his work.

ISADS’ aircraft concept studies fell into five categories: minimum cost, minimum weight, minimum penetration time, minimum observables (stealth), and laser defense. Raymer’s low-cost designs included several modular (and therefore easier to build) designs; a nuclear sea sitter; and an untapered wing that would be simpler and therefore cheaper to build, and swept forward (along with a swept-forward canard) for better aerodynamics. This design had the lowest cost per pound of all the designs, but the result would have been heavier and therefore much more expensive. A hydrogen-propelled jet engine was also considered, but hydrogen takes up too much volume—more than that of the plane! The fuel tanks would have too much surface area, which would be deadly for any plane that has to fly fast at low altitudes.

Raymer next described his stealth concept designs. His premier example was the Delta Spanloader. Model wind tunnel test results were similar to wing-alone results: the test engineer exclaimed “that’s the best test we ever ran!” The Spanloader was widely reported, even in Russian journals. Upon increasing its wing span, it became efficient at high as well as low altitudes. The design was scaled down to A-10 size based on a Persian Gulf War simulation by Rockwell Ops Analysis staff—10 years before the actual war.

One study examined how to optimize first-strike survivability. What if the Russians were to attack all air bases? Planes that could fly for days would avoid attack. The planes in question each carried an ICBM so they did not need to be especially fast, just fly for a long time and carry and launch their payload.

Raymer next described Rockwell’s approach to the Advanced Tactical Fighter program, on which he was Chief Engineer and Designer (1981-1984). The Air Force customer hadn’t yet decided whether the plane should be a transonic-optimized dogfighter, a strike fighter, a high-mach missileer, a cheap dogfighter or a stealthy missileer. Rockwell aimed to combine them—design a plane with supercruise, stealth, the F-15’s fighter maneuverability, and short takeoff and landing (STOL). How would this be possible? Initially, the team was to base their design on the HiMat, but as Raymer and a group of his colleagues disagreed, they formulated their own design—during their free time. This design ultimately became the F-22. However, Rockwell did not win the contract—Northrop and Boeing won with their flying wing design. (This and other “But we didn’t win the contract” comments prompted knowing, wry laughter from the industry veterans in the audience.)

The VTXTS advanced trainer program was to address the Navy’s need to replace the Rockwell T-2. Updating was in progress at the Rockwell Columbus, OH facility, but the Navy wanted an outright replacement instead and diverted the project money to the California Rockwell facility for that purpose. Raymer noted that his design included the tail of the F-18 tail because it was “new and cool”. However, trade studies indicated that other designs would be better. In the end, the Navy awarded the contract to British Aerospace (BAE) and McDonnell Douglas for the T-45, a single-engine plane.

Raymer’s next example was the Rockwell/Messerschmitt-Bölkow-Blohm (MBB) X-31 Supermaneuver Demonstrator, invented in the 1970’s by Wolfgang Herbst, MBB’s Vice President for Advanced Design. The basic idea was to pitch to an extreme angle of attack early in a combat turn, then yaw to point the nose at the enemy. The collaboration of Germany and the US was thought to reduce the chance of the project being cancelled, which could otherwise cause an international incident. MBB oversaw the design of the wing shape and canard. Attempts to minimize the cost of the X-31 failed—the initial estimate came in at $40 million, but the final budget reached $400 million. Still, the plane flew many successful missions and even participated in the 41st Paris Air Show in 1995.

Raymer was the Chief of Air Vehicle Design in the early studies, but left Rockwell midway through the program (in 1986). He joined the Aerojet Propulsion Research Institute as Director of Future Missions, and began consulting for the RAND Corporation.

Raymer described the Hi-Lo strategy (designing and producing a mix of high-performance but high-cost fighters and less capable but far cheaper planes) in the context of the Low-Mix Fighter—Next Generation Attack Fighter (NGAF) F-35. The F-35 was to replace the F-16 (low) to improve upon its stealth and supercruise capability. Raymer’s job was to define a credible replacement aircraft for the F-16 and perform trade studies to aid in the requirements selection. The design had a canard and a four-tail configuration similar to the F-18. However, this design’s disadvantage was that the wing flapped too far to the rear and therefore had to be bigger, adding to the drag; they switched to an aft tail design. Raymer’s involvement began at Rockwell but continued at RAND, which was advising the Air Force on requirements for the F-16 replacement while considering the cost. The various studies included tailless aircraft designs, which would reduce weight and drag, and be cheaper—but could they be flown?

In 1987, Raymer joined Lockheed Martin as the Director of Advanced Design. At the time, ASTOVL (Advanced Short Takeoff and Vertical Landing) (Supersonic Harrier Replacement) was under way at Lockheed in collaboration with Rolls-Royce and BAE. The best approach for a supersonic fighter involved “Lift Plus Lift/Cruise” in which a second engine has the exhaust pointing downward to add lift. The first engine has nozzles likewise spewing its exhaust downwards. The plane can balance on the combined lift. However, the Russians had already done this in their vertical takeoff jets, and DARPA wanted something new—leading to the RIVET concept (Reverse Installation, Vectored Engine Thrust). Later, Raymer worked with the Center for Naval Analysis on a version of ASTOVL for both Navy and Marine pilots, designed to land on aircraft carriers (Catapult-Assisted Take Off, Vertical Land). Ultimately, the Lockheed facility in Burbank closed; Raymer then began teaching at California State University at Northridge. He also started Conceptual Research Corporation, an aerospace design and research company.

Raymer also described his work on Unmanned Tactical Aircraft or UTAs, now known as UAVs, which brought up concerns about putting robots in charge of weapons. He described the Subsonic Stealth UTA, now called the Unmanned Combat Aerial Vehicle, noting that it never crashed even if shot! Later, Raymer did further target drone work as a consultant for Composite Engineering Inc. (CEi), a composites component design and fabrication house that saw a new business opportunity in replacing the aging jet target drones on the market. Specifically, CEi was aiming to replace the MQM-107 and BQM-34. He also described the CEi Surfer and the CEi Firejet.

Lastly, Raymer spoke of future studies—the NASA Advanced Technology Subsonic Transport Study, or Advanced Commercial Transport Concepts and Technologies or N + 3—three generations beyond today’s commercial airliners. Raymer is supporting a group using a Boeing 737 analysis model for baseline parametric trade studies. The goal: to reduce fuel usage—by 70%. Several designs included large propellers called rotors, to increase the efficiency of the jet engine. However, these were noisy except for a shielded rotor design. Designs to reduce the wetted area included two engines packaged into a single nacelle; a blended wing-body (good for planes carrying higher numbers of passengers, otherwise a waste of space); two tailless open rotor designs with pop-out canards for takeoff and landing only, with only the wings controlling the flight in between; the C-wing (winglets with winglets); and a 3-surface (aft tail and canard).

Those who stayed after the talk were in for a treat: Raymer escorted them around the airplane mockups parked on the grounds surrounding the Proud Bird, telling about the original planes. In one juicy story, Raymer pointed out that while Chuck Yeager was known as the first pilot to officially break the sound barrier, the noted World War II pilot George Schwartz Welch—known as “Wheaties” because his picture was on a cereal box—took a F-86 Sabre into a dive from 35,000 feet and claimed to have reached supersonic speed. Some people reported hearing a sonic boom; however, his instrument readings were in doubt. The Air Force, which wanted Yeager to have the record, ordered “Wheaties” not to do that again! However, half an hour before Yeager was to make his famous flight, “Wheaties” went into a dive from 37,000 feet and another sonic boom was heard. But to make sure Yeager was recorded as being the first to fly at supersonic speeds, the wording “in level flight” was added to the record.

More details on Raymer’s talk topics, as well as more stories and aerospace designs, can be found in his book Living in the Future: The Education and Adventures of an Advanced Aircraft Designer (Design Dimension Press, Los Angeles, CA, 2009; ISBN 9 780972 239721 visit for more detail and to order). Aerospace industry veterans and laypeople alike will enjoy this book. Visit Daniel Raymer’s website for links to his books, aircraft design software, short course information, design drawings, blog, and more resources for aircraft designers.

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