What is aircraft transponder code 0000?

Series 00 — Code 0000 is available to any State for general purposes. (Codes 0001 to 0077 are available for domestic purposes.) Series 20 — Code 2000 is to recognize an aircraft that has not received instructions from the air traffic control units to operate the transponder.



People Also Ask

0000 — A generic code that is not assigned and should not be used. 1200 — VFR aircraft. The default code for all flights–if you aren't asked to set anything else, you should set 1200. 7500 — Hijacking. 7600 — Voice radio failure.

MORE DETAILS

Aircraft in an emergency, who are not receiving an air traffic service should set the transponder to EMERGENCY (Mode 3A Code 7700) as part of their initial actions. A pilot may select Mode 3A Code 7700 whenever he has specific reason to believe that this would be the best course of action [ ICAO Doc 8168 Vol 1.]

MORE DETAILS

Squawk 7000: This is the 'conspicuity code' for VFR aircraft that are not assigned a specific code by ATC. Squawk 2000: This is the 'conspicuity code' for IFR aircraft that are not assigned a specific code by ATC.

MORE DETAILS

Series 20 — Code 2000 is to recognize an aircraft that has not received instructions from the air traffic control units to operate the transponder.

MORE DETAILS

For example, 1200 in the USA means that the flight is flying under Visual Flight Rules (VFR) and is not typically in direct contact with ATC. 1200 is a shared code so you may see many aircraft transmitting it at the same time in a given area.

MORE DETAILS

If the 7500 squawk code is mistakenly selected, the pilot will immediately receive a call from air traffic control asking for confirmation. At this point, the pilot in command or the first officer is able to inform the transponder code has been used by mistake, and that there is no hijacked aircraft.

MORE DETAILS

Famous Squawk codes These special codes are standardized by the International Civil Aviation Organization (ICAO), so seeing an emergency code in Denver means the same thing as seeing the code in Delhi. The first of these is the code 7500, which signals “unlawful interference,” more commonly referred to as hijacking.

MORE DETAILS

Squawk 1000 is a code assigned by air traffic control to indicate that an aircraft is experiencing an emergency.

MORE DETAILS

There are a few significant squawk codes, which immediately get the attention of air traffic control. For a longer discussion of squawk codes and emergencies, please see our discussion with a pilot and an air traffic controller. 7500: Hijack. 7600: Radio Failure. 7700: General Emergency.

MORE DETAILS