Unsafe At Any Airspeed?

Airlines, aircraft and equipment manufacturers, and regulators need to make greater use of classic tools of risk analysis to examine the problem of RF interference. Given the enormous diversity and complexity of the systems involved, the constantly changing aircraft environment, and the limited analytical resources, however, such conventional studies cannot identify and assess all important potential accident sequences. We recommend five broad strategies to foster adaptive management and control, listed here in approximate order of importance and feasibility:

1. Expand industry-government cooperation: Most airlines do not have adequate resources to evaluate all systems under development, nor, given the pressures of competition, do they rush to share the results of their research. A joint effort is clearly needed, and in the interests of public safety, some federal money should be provided to augment airline resources. The FAA, FCC, National Transportation Safety Board, airlines, and aircraft and equipment manufacturers should form an industry-government cooperative program to evaluate, test, and promote better communication between aviation professionals and the public. All airlines operating in the United States should be required to participate. There already is a voluntary not-for-profit corporation well suited to the task--RTCA Inc., in Washington, D.C. (originally known as the Radio Technical Commission for Aeronautics)--that develops consensus-based recommendations. Its committees on PEDs have served the purpose but have convened too infrequently to be effective. Given the dynamic growth of PED use, a standing committee is needed.
2. Augment the Aviation Safety Reporting System: NASA's ASRS should once again support statistically meaningful time-series event analyses. The ASRS, a cornerstone of aviation safety, has issued more than 4000 safety alerts; outside researchers have drawn on its database to produce at least 60 safety-related reports and papers. Because the practice of including an identifiable random sample of incidents was dropped (because of budget cuts), the ASRS can no longer be used to do statistically valid studies of all types of incidents, including those involving PED interference. Congress should provide budgetary support to reinstate the random sample entries or, better yet, to enter all the received reports.
3. Continue in-flight RF spectrum measurements: Improved and ongoing characterization and analysis of the onboard RF environment will yield many benefits. Our research has been only a modest start. It would be relatively straightforward to install RF detectors in aircraft cabins that would continuously monitor and record high field strengths in several spectral bands, much as we did in our research. The data can then be stored on flight data recorders--the familiar "black boxes" that serve as tools when airplane crashes are investigated. Modern flight data recorders have hundreds of channels for recording data, and the major airlines routinely apply data-mining methods to the records from each flight to improve operational efficiency and quality assurance and to search for anomalies that could indicate problems.
4. 4. Enable real-time monitoring by flight crews: The deployment of simple real-time tools to help flight crews detect RF emissions would help reduce risks. If flight crews or airliners had RF detectors, then they could take corrective action when they noticed strong electromagnetic emissions. The crew could more closely monitor its avionics, especially during critical flight phases such as final approach and landing. If such observations ultimately identify particular types of electronic devices that are seriously troublesome, then legal or other means should be available to keep them off airliners in the future. Currently, there is no systematic way to keep offending devices off flights.
5. 5. Harmonize RF emissions standards: In today's world, with vast numbers of consumer electronic devices being used, either legally or illegally, on airplanes, it no longer makes sense for the FCC alone to set emission standards and policies. Clearly, the FCC and the FAA should confer in establishing electronic device emission and susceptibility standards for avionics. If the expected growth of wireless technology leads to interference problems that are sufficiently grave, then it may prove necessary to adopt more aggressive controls. For example, the FCC could require manufacturers to include override capability in wireless devices so that they could be turned off by a centrally transmitted control signal during critical phases of takeoff and final approach. Such a deactivating capability might also prove beneficial in other life-critical settings, such as hospital critical-care facilities. This type of regulation, of course, raises important questions of civil liberties and social vulnerability.

Passengers must also be informed of the very real risks posed by their use of PEDs, especially on flights that use GPS approaches. Turkish Airlines' announcement is straightforward: "Mobile phones interfere with the flight instruments and have a negative effect on flight safety." The technical standards for GPS approaches could be modified to ensure that any loss of signal is immediately flagged to the crew, particularly during landings.

Taken together, the actions outlined above should enable regulators and the airline industry to better characterize and manage the risk that RF emissions from consumer electronics poses to aviation safety. In an industry that has eliminated or is effectively managing most large and obvious sources of danger, such small but persistent risks warrant serious attention. At present, we believe that passenger use of electronics on board commercial aircraft should continue to be limited and that passengers should not be allowed to operate intentionally radiating devices such as cellphones and wireless computer equipment during critical stages of flight.