of commercial airplanes have reported numerous cases of portable
electronic devices affecting airplane systems during flight. These
devices, including laptop and palmtop computers, audio players/recorders,
electronic games, cell phones, compact-disc players, electronic
toys, and laser pointers, have been suspected of causing such anomalous
events as autopilot disconnects, erratic flight deck indications,
airplanes turning off course, and uncommanded turns. Boeing has
recommended that devices suspected of causing these anomalies be
turned off during critical stages of flight (takeoff and landing).
The company also recommends prohibiting the use of devices that
intentionally transmit electromagnetic signals, such as cell phones,
during all phases of flight. The U.S. Federal Communications Commission
already prohibits the use of cell phones during flight. In addition,
the U.S. Federal Aviation Administration issued Federal Aviation
Regulation 91.21 to make operators responsible for governing the
use of portable electronic devices on their airplanes.
(EMI) from passenger-carried portable electronic devices (PED) on
commercial airplanes has been reported as being responsible for
anomalous events during flight. The operation of PEDs produces uncontrolled
electromagnetic emissions that could interfere with airplane systems.
Airplane systems are tested to rigorous electromagnetic standards
to establish and provide control of the electromagnetic characteristics
and compatibility of these systems. However, PEDs are not subject
to these same equipment qualification and certification processes.
Though many cases of EMI have been reported over the years, with
PEDs suspected as the cause, it has proven almost impossible to
duplicate these events. Boeing has participated in several related
activities and has revised its all-model service letter for concurrence
with the U.S. Federal Aviation Administration (FAA) advisory circular
(AC) on the use of cell phones while airplanes are on the ground.
However, operators and their flight crews are ultimately responsible
for deciding whether to allow the use of PEDs.