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The Limits of Open Source - Jet Engine Control Software Won't Go Open Source

My brother manages jet engine control, software development for the Aircraft Engine Division of General Electric. GE is the largest manufacturer of jet engines in the world, selling more than its two primary competitors combined, Pratt Whitney and Rolls Royce. These competitors sell enough however, that there is no way to regard GE as a monopoly. Because GE is bigger, it's reasonable to conclude that it can invest more in it's engine control software development. As a result GE jet engines are likely to be better than its competitors.

Ignoring any possible legal issues (anti-competitive collusion), if one applied open source arguments to this software application, one would conclude that if GE, Pratt Whitney and Rolls Royce collaborated on jet engine control software, and made the results public as open source for scrutiny by other engineers, the result would be better jet engine control software. There is no reason to limit this cooperation to software as most of the arguments regarding software can be applied to other engineering issues. All three major jet engine manufactures would make better engines if they shared all their engineering knowledge. Taking this even further, all this engineering knowledge could be made publicly available under open content licensing, which would help the small specialty jet engine manufactures to make better jet engines too.

There is a major problem with this approach aside from legal. GE effectively gives up its primary competitive advantages in this model. What possible, rational reason would one of the most successful companies in the world have, for giving up its primary competitive advantages, just so it could make a somewhat better engine. GE's reason for being is not to make the best possible jet engine, but to make a profit for it's shareholders.

The market recognizes that GE already makes the best jet engines in the world. For those who don't know, jet engines are generally purchased separately from aircraft bodies they propel. An airline can order a Boeing 747, or most other models, with the engines from any manufacturer who makes an engine appropriate to that model plane, typically the big three, GE, Pratt Whitney and Rolls Royce, for large commercial airliners.

These are not casual consumer purchases influenced by marketing hype. These are large corporations with knowledgeable staff, making purchasing decisions in a competitive market. The clear market preference for GE engines suggest that most buyers think GE builds better engines for their purposes. That Pratt Whitney and Rolls Royce remain viable competitors means that their engines offer enough points of differentiation, that the buyers of these engines see enough advantages to these products to keep Pratt Whitney and Rolls Royce in active competition with GE.

I used this example because it meets every test I know of, for a competitive market working the way it should. There are no first to market issues: GE claims a 120 year history. F. H. Royce & Co. was founded in 1884 and became Rolls-Royce Ltd. in 1906. Pratt Whitney was formed in 1925. All predate jet engines, which are about 70 years old, by at least 15 years. Primarily however its a competitive market in which knowledgeable buyers operate. The buyers aren't free to pick features based on whim; engines must meet reliability and safety standards, they must deliver necessary thrust while maintaining good fuel economy (airlines second major expense after employees), and must operate within certain noise limits. While there are other methods of defining best, in a competitive market, clear market leaders are generally accepted as the best. If you don't like this then don't argue with me; please take your arguments to the appropriate economic or political forum. Following the collapse of Communism more than a decade ago, the majority of the (industrial) world accepted that some variation on a market economy represented the best way to organize an economy.

In the short run, the open source / open content model might result in somewhat improved engines from the three major manufacturers. It would also likely result in improved engines from the smaller manufactures as well.

There is also the possibility that the resulting software would be inferior. Jet engine control software has an intimate relationship with the hardware it controls. To the extent that the engines built by the different manufacturers are physically different, the control software needs to account for these differences. The software either needs to detect the hardware it is controlling and dynamically invoke the appropriate code or the appropriate code needs to be statically linked. In either case custom code needs to be developed for hardware that is different. This is analogous to hardware drivers for network and video cards.

On a PC, it might be OK to use a generic network card driver that doesn't take advantage of every feature of a specific card but uses only the lowest common denominator features of the underlying chip set. On jet engines with critical safety and fuel efficiency issues, it's not likely a "generic" driver will be good enough. The jet engine manufacturers surely purchase some number of subassemblies. Where these happen to be common to all manufacturers, joint software development is likely to result in better software. Where different manufacturers have selected different subassemblies or build their own parts in a different manner, joint software development will introduce overhead to account for these differences. Since what we are discussing is hardware control software in the first place, no one without access to large amounts of currently proprietary information from all three companies can even make an educated estimate as to how joint (open source) software development would impact the quality of the resulting software. It's pure speculation that the result would be better software.

What is not speculation is that an open source software development and engineering model would eliminate most of GE's competitive advantages over the entire market and the big three's advantage collectively over the remaining market. Only economy of scale would be left to the big three, as most of the proprietary engineering and software knowledge that was previously their primary basis for competitive advantage, would be gone.

Assuming initial improvements from sharing, it's not at all clear that the big three would have any reason to pursue extremely expensive, further independent innovation as each of their competitors would gain as much as the innovator, putting the innovator at a disadvantage because the innovator would have higher costs. Further, it's pure speculation that the jet engine industry could coalesce and develop any cooperative development model that's better than the existing competitive model. Again, anyone who does not like this should be arguing in an appropriate economic or political forum, because this is a simple fact of how the industrial world is organized today and for the foreseeable future

It's pure fantasy to think that GE would ever cooperate with its competitors in such a way that GE relinquished it's primary competitive advantages and a proven profit model to pursue an arbitrary goal of building a better jet engine than it already does using an unproven development model. As an airline passenger, I'd rather ride on planes powered by engines built under the competitive model than the hypothetical cooperative model that's under discussion.

The GE example raises a specific example of a more general case. By definition, the open source model assumes a multiplicity of user developers. In doing so, it de emphasizes the overhead involved whenever software is designed to deal with a differing hardware or otherwise adapt to differing environmental factors whether they are hardware, software, or network. Anyone who has done software development knows that complexity increases rapidly as software is designed to be configurable to work in different environments. This is nothing other than choices equal complexity.

The open source movement virtually owes its existence to UNIX. A fundamental characteristic of UNIX (and most open source products) is modularity. Relatively small and simple functions or utilities are put together as needed to adapt to the specific situation. The only efficient way to do this is with scripts and scripts are software. Thus UNIX and open source presuppose unique software that does not lend itself well to the open source movement.

Every administrator who writes a script and every programmer who writes a function could make these available via open source licenses. If you've been in the computer business a significant period of time you know that after a programmer reaches a certain level of proficiency with a language, it becomes simpler and faster for that programmer (or programming team) to develop their own custom function library than to try to find ready made functions for every task for which a function is appropriate. Likewise, system administrators reach a level of proficiency with their preferred scripting language and knowledge of their environment that simple custom scripts are written without even searching for examples.

As problems become more complex, the experienced programmer or administrator will spend time looking for a ready made solution. Where the problem being solved really is similar, the joint development model does make sense but if the problem is unique, the open source model, by definition cannot provide an answer. Thus open source makes the best sense where the problem is complex and shared by many, e.g., operating systems. Even complex problems, if they are unique will not be solved by open source methods.

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