PEDs Off for Low-Visibility Approaches

March 4, 2017

PEDs Off for Low-Visibility Approaches


Captain George Nolly

In a recent episode of the Airline Pilot Guy podcast, there was a discussion about whether an air carrier should require passengers to turn off all personal electronic devices (PEDs) prior to initiating a low-visibility (Cat III) approach. There was a bit of disagreement over whether this was necessary, and it is currently not a requirement for passengers to turn off their PEDs at certain U.S. airlines. Of course, there is no assurance that all passengers will comply, either intentionally or unintentionally.

Since I have worked for three airlines that conduct Cat III approaches (United, Jet Airways and Omni), and there is little consistency among them regarding this subject, I would like to share my thoughts.

Over 20 years ago, before PEDs were ubiquitous, I was a B727 Captain. During one flight, I was making an ILS (Cat I) approach and the localizer needle would periodically twitch to full-scale deflection and then return to the center. I knew it was not caused by any variation in my flying, and thought it might be some sort of instrument error. Then, on a hunch, I asked the First Flight Attendant to check the cabin to see if anything unusual was going on with any passenger electronics. She reported that a passenger was playing with his Gameboy. I had her instruct the passenger to turn it off until after we landed, and the ILS immediately stabilized.

Nowadays, most PEDs are much more secure than the primitive hand-held games, and numerous tablets and computers have been tested and authorized for use on airplanes. For example, many air carriers issue iPads to their flight crew members to use as Electronic Flight Bags (EFBs). These devices have been rigorously tested by the FAA before they were authorized for use, and we can presume the same devices in the hands of passengers would pose no safety threat.

Before we discuss PEDs any further, it’s important to first discuss an air carrier’s duty and responsibility with regard to safety. 49 U.S. Code §44701 emphasizes “the duty of an air carrier to provide service with the highest possible degree of safety in the public interest”. Exactly what does that mean? FAA Order 8900 explains, “An air carrier’s duty to provide service with the highest degree of safety in the public interest means that the air carrier must identify hazards in its operating environment and manage associated risks. Similarly, an air carrier’s ability to manage risk is an important part of the FAA’s determination to ensure that the air carrier is equipped to operate safely under 49 U.S.C., and the regulations and standards prescribed by 49 U.S.C.”

To put it in practical terms, let’s consider the case of a homeowner. If it snows, a homeowner’s responsibility to exercise a normal degree of safety would be to shovel the snow off the sidewalk. If the homeowner were to exercise the highest possible degree of safety, he would shovel the sidewalk, then use a broom to remove excess snow, then use a hairdryer to completely dry every inch of the concrete.

So now let’s look at the case of an air carrier airplane making a Cat III approach. This is an approach that does not have a decision height, only an alert height. When there is a decision height, such as with a Cat I or Cat II approach, the pilot must look out the front window and decide if the airplane is in a position to land. This is not the case with a Cat III approach. In a Cat III approach, the airplane is completely controlled by the autopilot throughout the approach and landing. The pilot does not make a decision as to whether the airplane is in a position to land, because during visibility conditions requiring a Cat III approach the pilot will not see the runway until the nose is lowered (by the autopilot) during landing. I’ve made several of these landings, and there is no doubt that the safety of the airplane is totally dependent upon the accuracy of the airplane’s autoflight/approach system.

So, can that accuracy be affected by PEDs? According to Boeing’s Aero Magazine, “PEDs are classified as either intentional or non-intentional transmitters of electromagnetic signals. Those that intentionally transmit signals outside the device must do so to accomplish their functions. Examples of these PEDs are cell phones. remote-control toys. two-way pagers. and two-way radios.

Non-intentionally transmitting PEDs do not need to transmit electromagnetic signals  outside the device to accomplish their functions. But like any electrical or electronic device, they will emit some level of radiation. Depending on the characteristics of this radiation, interference with the operation of other electronic devices can occur. For example, operating an AM radio close to a fluorescent light will cause static in the reception of the radio signal. Examples of non-intentional transmitters are audio players and recorders. compact-disc players. electronic games and toys. laptop computers. laser pointers. and palmtop computers”.

NASA publication NASA/CR-2001-210866 has several charts showing the effects of PEDs on airplane systems. The note appended to Chart 10 states,  “Chart 10’s significance is the order of magnitude higher that navigation systems above all other systems were affected by PED anomalies.”

In light of this information, let’s perform a cost/benefit analysis of requiring all passengers to secure their PEDs.

Cost: Some passengers may be upset, and some may surreptitiously continue to operate them. Additionally, some passengers may inadvertently have PEDs operating, such as the case where they forgot to turn them off upon boarding.

Benefit: Safety will be enhanced to the highest possible degree by minimizing spurious emissions by older, unapproved, PEDs. Remember the Gameboy.

I contend that, to comply with 49 U.S. Code §44701, the prudent course of action for all air carriers is to require that all PEDs be turned off prior to commencing low-visibility approaches.