ELECTROMAGNETIC INTERFERENCE WITH AIRLINER ON-BOARD COMMUNICATIONS AND NAVIGATION SYSTEMS ASSOCIATED WITH THE USE OF PASSENGER-CARRIED PORTABLE ELECTRONICS EQUIPMENT
Persistent reports have linked electromagnetic interference (EMI) with airliner on-board communications and navigation systems with the use on such aircraft of passenger-carried portable electronic equipment (Nordwall, 1993, p. 32). The problem is exacerbated by two developments--portable electronic equipment has proliferated, and the smaller size and low-voltage characteristics of modern aircraft electronics causes them to be increasingly vulnerable to EMI. In response to these events, some airlines began restricting the use of portable electronic equipment by passengers (Westlake, 1993, p. 64). Among the equipment the use of which was restricted were mobile telephones, radios, compact disc players, laptop computers, cassette tape players, and calculators. The use of some types of equipment is prohibited during entire flights, while the use of other types of equipment is restricted only during take-offs and landings.
Aircraft use a range of the electromagnetic spectrum from dc for some monitoring equipment to 10Ghz for weather radar (Geppert, 1994, p. 21). The electromagnetic range used by portable consumer electronic equipment is almost as broad. While instances of interference does occur as a result of this sharing of the electromagnetic spectrum within an aircraft's in-flight environment, the EMI is not consistent. This inconsistency creates problems for engineers attempting to design around the problem and for airlines attempting to develop policies that promote in-flight safety while not antagonizing passengers.
Electromagnetic interference from portable electronic devices on aircraft was first determined during the 1950s when one of the frequencies emitted by portable FM radio receivers interfered with the normal operation of the aircraft communicati...