Flightradar24 !

[Cessna182]

Hva betyr det som står over radarbildet, f.eks. "Latest Twitter squawk 7700". Er ikke 7700 squawk'n for emergency ?

[Twin Otter]

FR24 sender automatisk ut en tweet når det detekteres at et fly endrer squawk til enn nødkode. Så da kan man raskt klikke seg inn på radaren og følge med på hvor flyet tar veien.

[scanhorse]

Hej her kommer lidt om 7700 codes og andre
transponder codes :


http://en.wikipedia.org/wiki/Transponder_%28aviation%29

Routine codes

0000:
Military intercept code (in the U.S.)[11]
Mode C or other SSR failure (in the UK).[12]
Shall not be used — is a non-discrete mode A code (Europe)[13]
0021: VFR squawk code for German airspace (5000 feet and below) — from 15 March 2007 replaced by the international 7000 code for VFR traffic.[14]
0022: VFR squawk code for German airspace (above 5000 feet) — from 15 March 2007 replaced by the international 7000 code for VFR traffic.[14]
0033: Parachute dropping in progress (UK)[12]
0041 to 0057: In Belgium assigned for VFR traffic under Flight Information Services (BXL FIC)
0100: In Australia: flights operating at aerodromes (in lieu of codes 1200, 2000 or 3000 when assigned by ATC or noted in the Enroute Supplement Australia)[15]
1000:
Instrument Flight Rules (IFR) flight below 18,000' when no other code has been assigned (Canada)[6]
Non-discrete mode A code reserved use in Mode S radar/ADS-B environment where the aircraft identification will be used to correlate the flight plan instead of the mode A code[13]
1200:
Visual flight rules (VFR) flight, this is the standard squawk code used in North American airspace when no other has been assigned.[6]
In Australia civil VFR flights in class E or G airspace.[15]
1202:
Visual flight rules (VFR) glider flight, this is the standard squawk code used in United States airspace for transponder equipped gliders when no other has been assigned.[16]
1400: VFR flight above 12,500'ASL when no other code has been assigned (Canada)[6].
2000:
The code to be squawked when entering a secondary surveillance radar (SSR) area from a non-SSR area used as Uncontrolled IFR flight squawk code in ICAO countries[13]
In Canada for uncontrolled IFR at or above 18,000'[6]
In Australia: civil IFR flights in Class G airspace.[15]
2100: Australia: Ground testing by aircraft maintenance staff.[15]
3000: Australia: Civil flights in classes A, C and D airspace, or IFR flights in Class E airspace.[15]
4000:
Aircraft on a VFR Military Training Route or requiring frequent or rapid changes in altitude (U.S.)[17]
In Australia: civil flights not involved in special operations or SAR, operating in Class G airspace in excess of 15NM offshore.[15]
4400 to 4477: Reserved for use by SR-71, YF-12, U-2 and B-57, pressure suit flights, and aircraft operations above FL600 (USA only).[17]
5000: Aircraft in Military Operations[15]
6000: Australia: Military flights in Class G airspace.[15]
7000:
VFR standard squawk code when no other code has been assigned (ICAO)[13].
UK: this code does not imply VFR; 7000 is used as a general conspicuity squawk.[12]
7001:
Sudden military climb out from low-level operations (UK)[12]
Used in some countries to identify VFR traffic (France, ...)
7004: Aerobatic and display code in some countries.[12]
7010: VFR circuit traffic code in the UK
707X: Paradrop activities in France (7070, 7071, 7072...)
7615: Australia: civil flights engaged in littoral surveillance.[15]
7777:
Military interception (U.S.) ("Under no circumstances should a pilot of a civil aircraft operate the transponder on Code 7777. This code is reserved for military interceptor operations.")[18]
Non-discrete code used by fixed test transponders (RABMs) to check correctness of radar stations (BITE). (U.S., Germany, Netherlands, Belgium, ...)

[edit] Emergency codes

7500: Unlawful Interference, i.e., Aircraft hijacking[6]
7600: Lost Communications[6]
7700: General Emergency[6]

[edit] Codes assigned by ATC

Most codes above can be selected by aircraft if and when the situation requires or allows it, without permission from ATC. Other codes are generally assigned by ATC units.[7][6] For IFR flights, the squawk code is typically assigned as part of the departure clearance and stays the same throughout the flight.[7][6]

VFR flights, when in uncontrolled airspace, will "squawk VFR" (or conspicuity code in the UK)[19](1200 in the U.S., 7000 in Europe). Upon contact with an ATC unit, they will be told to squawk a certain unique code. When changing frequency, for instance because the VFR flight leaves controlled airspace or changes to another ATC unit, the VFR flight will be told to "squawk VFR" again.[7][6]

In order to avoid confusion over assigned squawk codes, ATC units will typically be allocated blocks of squawk codes, not overlapping with the blocks of nearby ATC units, to assign at their discretion.

Not all ATC units will use radar to identify aircraft, but they assign squawk codes nevertheless. As an example, London Information — the Flight Information Service station that covers the lower half of the UK — does not have access to radar images, but does assign squawk code 1177 to all aircraft that receive a FIS from them. This tells other radar equipped ATC units that that specific aircraft is listening on the London Information radio frequency, in case they need to contact that aircraft.[19]