Number 289
October 2003
A Monthly Safety Bulletin from The Office of the NASA Aviation Safety Reporting System
P.O. Box 189, Moffett Field, CA 94035-0189

Missed Comunications

Pilot's headsetCommunication problems are mentioned in a high percentage of incidents reported to ASRS. Misunderstandings account for the greatest number of communication errors, but improper radio operation and equipment malfunctions are also culprits.

Private Conversation

A misplaced switch, apparently overlooked during the cockpit preflight, resulted in this A300 Captain transmitting to a very limited audience.

A Classic in D - Unplugged

"Check the plug" is the classic first step for troubleshooting many electronic devices. An unplugged headset caused an embarrassing departure for this BE35 pilot.

Talk, Don't Squawk

A corporate pilot reported on a number of difficulties encountered when flying with a contract pilot. The problems started with this communications error.

Stealth Communications

While military pilots might be familiar with radio silence procedures, such operations are never intentionally conducted at civil airports. This private pilot, when confronted with the phrase "carrier no voice" apparently assumed that "zip lip ops" were in effect. What the controller was trying to convey to the pilot was that his radio was transmitting an unmodulated, constant tone (carrier frequency) without a discernable voice pattern.

A little "amplification" of the problem by Ground Control might have prevented this pilot from going as far as he did.


Misunderstandings cause many communication errors. The following ASRS reports illustrate the need for clear, unambiguous phraseology in all aviation operations.

A Recipe for Miscommunication

Blend distractions, assumptions, and misinterpretations. Add a little pressure. Arrange on a long, flat surface. For "well done" communications, clarify all ingredients before lifting off. For "half-Aircraft landing on runwaybaked" communications, lift off early- even if it feels wrong.

Runway Confusion...By Request

In two similar incidents, key information was left out of otherwise clear communications. In each case there were two different interpretations of the same phrase.

This runway incursion occurred because of a miscommunication. I will clarify a request like that in the future. If both the Tower and I were clearer in what we said, I believe something like this would never have happened.

A Bad Sign

Sign language is one of the oldest forms of communication, but even hand signals can be misinterpreted, especially when they are intended for someone else. Ramp Guidance person

ASRS Recently Issued Alerts On...
B737-300 fligth control malfunction
Southern airport landing traffic conflict
CL65 horizontal stabilizer trim problem
ATC handling of weather deviation request
MD-80 lavatory service with automotive fuel
September 2003 Report Intake
 Air Carrier/Air Taxi Pilots
 General Aviation Pilots