The Role of Size and Range in the Future of Aerospace Power Projection

"An Aero Guy's Perspective on the
Role of Micro/Nano Technology in Future Military Affairs"

Professor Alan Epstein
Department of Aeronautics and Astronautics, MIT

September 22, 2004

There is a lot of excitement because of the immense technical possibilities and large amount of money being invested in these technologies, both in Washington and among venture capitalists. The precise definition of nanotechnology is important given the level of funding that is being given to it. With these technologies we are really talking about the ability to manipulate atoms.

• Micro: refers to miniaturization. First devices in the 1970s. It's starting to get real. Rapid growth started about 1985. Example: MEMS (micro-electronic mechanical systems) gears, 100 nm across.
  
• Nano: involves new physics, chemistry, and biology. The working definition is it's nano if the properties of the object are different than they would be in bulk. Ex: semiconductor quantum dots for some lasers.
  
• Microscience and technology: silicon electronic chips, MEMS, micro-reaction arrays for drug discovery.
  
• Nanoscience and technology: large, but countable number of atoms. No atom is far from a surface. Integration of unique properties for macroscopic effects. Quantum dots for semiconductor lasers. Genomics. This isn't about miniaturization. It is about new physics, chemistry, biology.

But I'm an engineer, and for me miniaturization is all right. I don't care what's in the box as long as the box does something useful. Consider some past examples of dramatic reductions in size—the ENIAC vs. the Intel Pentium 4.

• There is an industry group that projects the future. Shrink continues on a 3 year slope per 50% reduction. Nanotechnology may enable trends to continue and get smaller, possibly to zero.
  
• Consider the idea that "quantity has a quality all of its own." Attributed to Stalin. What I maintain is that the same thing applies to things of military value today.
  
• Look at the density on a disk for disk storage—gigabytes per square inch. We may be reaching the limits of magnetic storage. IBM is turning to manipulation of individual atoms. They can demonstrate that there is the potential for very high densities.
  
• But what can all this do for me? What if I wanted to assemble a dossier on every person on the planet? How much storage and bit density would I need? For 1 page on every person on earth, you need about 10³ gigabytes per square inch. This can happen in 2005 or 2006. I don't know what you can do with this. People are finite, the planet is finite.
  
• What if I wanted to have a description of every square meter on the planet-everything about it and what has been observed there? We might have to wait for another 5 years to be able to put all that on a 3 1/2" disk.
  
• There are also new nano-engineered materials. Nanoscale fabrication will enable wholly new materials based on new science at the nanoscale. Historical it takes 20-30 years to go from the MIT bench to the system. No reason to believe nanotechnology will be any faster.

Possible military applications

• I'm going to take an MIT-centric approach, since we have the patents in this area, and focus on miniaturization. What used to be larger than a person is today smaller than your finger tip. Same functionality for a million times less weight. Things that used to go in bombers can now go in grenades or even bullets. Guided projectiles.
  
• Another aspect of MEMS is microchemical reactors. Chemical plants on a chip. Example: phosgene synthesis. Each one doesn't make very much of the chemical, though, so maybe you put one in each shell.
  
• Now let me talk about flying. This is the 100th anniversary of the Wright brothers. The NC4 was the first plane to fly across the Atlantic. It was the smallest airplane that could do the job. It had a crew of 6, weighed 27,000 lbs, and was representative of the technology of 1919. Move forward to 1927, and Lindbergh's plane weighs only 5,100 lbs and had a crew of one. The next milestone was the first commercial service, begun in 1939, with a seaplane weighing 84,000 pounds. The 747 is 700,000 lbs in 1970. They weigh even more now.
  
• As a technical matter, what is the next trans-Atlantic flight milestone? I'd say it's one that weighed 30 lbs. and flew at same speed and altitude as Lindbergh, in 1998. The miniaturization of the electronics and GPS lets you do this. Since then an 11 lb. airplane has done it.
  
• The old metric was how big you were. The new metric for the next 20-30 years is how small you are.
  
• Let's think about a military application and consider over time the sorties needed to destroy a 100 x 300 ft. building. In WW II, you needed 3,200 sorties to destroy the building, with huge crews on the air and ground. In Korea, you needed 550 sorties; in Vietnam, 44; in the first Gulf War, 8. And in the current war, 1. All these airplanes weigh the same, about 50,000 lbs. It's an improvement of 3000 to 1 in weight, 60,000 to 1 in people. You're down to 1 and it's tough to get less than one.
  
• How large is large enough to destroy a bridge? In 1971, a million pounds left the runway, and it cost about $10 million to destroy the bridge. In 1991, destroying a bridge took 2 Tomahawks with the same range as an F-4, 6,000 pounds left the ground, and it cost about $2.5 million. You saved money, no one was at risk, and you actually hit the target.
  
• So what's the future? Today it is incredibly even more precise. In 2021 maybe you can do it with 15 lbs. and $250,000. The technology is letting you get the same job done for much less money.
  
• In-service large UAVs designed for long endurance are also getting smaller.
  
• Consider as well the smaller systems now in service: Dragon Eye, Pointer. These have 3-4 foot wing spans and are 5-10 lbs. gross weight. They cost only $10,000 each. How small can these things go? There is a lot of variation in current UAVs from Black Widow to Global Hawk.
  
• Now let's think about where money is going in a typical strike campaign profile: about 2/3 of the cost is in the foreign bases—something you don't see in the defense budget. There is a lot of money in foreign bases that technology can free up.
  
• Micropocket engine. Our sponsor asked, what are you going to do with this stuff? These little airplanes are enabled by microelectronics. We're also looking at building small space launch vehicles, the size people could carry. Microsatellites are a possibility as well.

Summary remarks

• Micro systems (MEMS) ready to move into systems:
  - Mainly engineering rather than science
  - Dramatic reduction in system size and cost
  - New capabilities, not just replacement functionality
  
• Nantotechnology is in its infancy:
  - Enormous excitement
  - Qualitative and quantitative system implications not established
  
• System organization, complexity, and design may pace applications
  
• Many new military systems can/will be much smaller
  
• Both micro and nano may be most important as new threats. Other countries that do not have as much invested in the heavier, bigger, older technologies may move into these areas and be able to challenge us with them.

What does the future hold?

• Consider the history of aeronautical predictions: at turn of last century we greatly underestimated the power of air flight and of the gas turbine. Now people may underestimate the possibility of these technologies.
  
• In the end, Thackery may be right: "how very small the very great are."

Rapporteur: Caitlan Talmadge

back to seminar summaries, Fall 2004