Ten minus Two?
Your piece on how airborne networks might evolve in the future (“10 Emerging Technologies,” May 2005) is a bit behind the times. The ability of aircraft to communicate their identities and positions to other nearby aircraft, and to take evasive action if necessary, has been flying for many years. It’s called the Traffic Alert and Collision Avoidance System, or TCAS. It equips planes with receivers that listen to the replies transmitted by other aircraft to interrogations from ground radars. A newer technology, called ADS-B, allows aircraft to broadcast their identities and positions.

None of this, however, has much to do with your article’s speculation that these technologies will allow “vastly greater numbers of small planes [to] zip in and out of thousands of small airfields.” Those small airplanes fly today with virtually no dependence on air traffic control by the Federal Aviation Administration. These planes have no problem now with crowding of the skies. The problems of crowded skies apply only to the planes that fly under control of the ATC system. The best in new automation won’t fix those problems until there are more runways on the ground. It doesn’t matter how efficiently we are able to get planes from here to there if there’s no concrete to land on.

Chuck Kengla
Potomac, MD

I was dismayed to see TR list mobile-phone viruses as an emerging technology. The threat of cell-phone viruses is vastly overblown. The wide variety of mobile operating systems limits a virus’s impact, and the Symbian viruses noted in the article require the user to click through several installation messages before the software is installed. Mobile-phone designers have learned from the lessons of PC viruses and have implemented a number of systems to protect users from viruses and malicious programs.

Carl Shimer
Oak Park, IL

Environmental Heresies
Stewart Brand should look more carefully at the economics of nuclear power (“Environmental Heresies,” May 2005). The underlying proposition of his pro-nuclear position is that in 30 years, using economies of scale learned from building thousands of nuclear plants, we can drive down the capital costs so that reactors produce energy at a price competitive with today’s dirty coal. However, given
30 years of R&D and economies of scale, battery-backed photovoltaic power will cost less than electricity produced from coal or nuclear. Out in the desert, solar-generated hydrogen will still cost less than nuclear hydrogen. The other developments that Brand highlights will reduce or alter energy consumption in ways that will make breeder nuclear reactors unnecessary: negawatts to use energy more efficiently; displacing natural-gas consumption with geothermal heat pumps or solar thermal panels; falling populations that require less energy; and genetic engineering to design bacteria optimized for generating methane.

Chuck Simmons
Redwood City, CA

Who Needs an Energy Policy?
The “Readme” editorial about the lack of a strong federal energy policy (“Fossilized Policy,” May 2005) raises two questions. First, why should there be a national policy? Second, why does a viable technology on the verge of commercialization need state support? There are several countries – from France and Germany to Russia and Japan – with national policies on every subject. They have been clearly outperformed by the United States over the last century. The reasons are simple: the greater U.S. protection of individual rights to life, liberty, and property permits a competitive discovery process for the best use of resources.

Kartik B. Ariyur
Minnetonka, MN

Warming to the Topic
In his review of Michael Crichton’s latest novel, State of Fear, Joseph Romm expresses dismay that Crichton dares to question the validity of carbon dioxide-caused global warming (“Greenhouse Gas,” May 2005). Perhaps Romm should read the article in Regulation magazine by MIT meteorology professor Richard S. Lindzen, in which Lindzen states that “as a scientist I can find no substantive
basis for the warming scenarios being popularly described.” He reminds us that better than 98 percent of the greenhouse effect is due to water vapor in the atmosphere, and that carbon dioxide, methane, and chlorofluorocarbons are relatively minor greenhouse gases. If there is any “technological hubris” regarding this issue, it is the arrogant dismissal of those raising legitimate questions regarding carbon dioxide warming theories.

Anthony Stathoplos
West Hartford, CT

Renaissance Redux
Regarding Michael Hawley’s plea to “save the diversity of the individual” (“Whither the Renaissance Man?” May 2005): a recent trend in higher education is encouraging. Not long ago, I visited four universities with my high school-aged son. All four stressed a multidisciplinary approach and flexibility in their curricula and requirements to allow work in multiple subject areas. Thus, while the specialization trend we have seen over the last 100 years is likely to continue, in some areas it appears that our institutes of higher learning are responding to students’ interest in becoming – and industrial interest in hiring – more well-rounded people with multidisciplinary capabilities. Hawley should take heart: all is not lost.

Scott Simpson
Woodstock, CT

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