Use the Correct Transponder Mode

Make sure the transponder mode is ON while taxiing.

Tip Transponder

The mnemonic lights, camera, action reminds pilots to turn the transponder to ALT before lifting off in controlled airspace. But did you know that the FAA recommends activating the transponder while on the ground? You may have been trained to put the transponder in STBY mode while taxiing. But this practice no longer satisfies the recommendations of the AIM (Aeronautical Information Manual).

The wording in the AIM regarding the use of transponders was modified last year. Regarding ground operations the AIM states: “Civil and military transponders should be turned to the “on” or normal altitude reporting position prior to moving on the airport surface to ensure the aircraft is visible to ATC surveillance systems.”

So instead of turning the transponder to STBY when you start up the airplane or after you exit the active runway, you need to turn it to ON.

If you’re flying an airplane with a modern transponder, whether of the stand-alone type or one built into an integrated system like the Garmin G1000, you have to pay attention to what mode is selected. Many transponders have automatic features that switch the transponder to STBY when the avionics are turned on, ALT when you take off and back to STBY after the airplane lands. The setting is generally based on the current speed. If your transponder sets itself to STBY, you need to override the setting to ON while taxiing.

And rather than having to push the ON button each time the systems defaults to STBY, you can change the configuration so that it goes to the ON setting instead. In some cases it is simple enough that you can do it yourself. But should you need to enlist the help of an avionics shop it should be an easy, inexpensive fix.