Emergency squawks0
Squawk 7500, 7600 or 7700 — hijack, radio failure or general emergency. Usually a keying error, occasionally not.
None right now.
Military0
Tagged as military in the aircraft database that ships with the decoder.
None right now.
Limited-data aircraft1
Registered with the FAA's LADD programme, which limits how their data may be displayed.
23,175 ft · 463 kt · squawk 2705
Less common types23
Anything that is not the everyday A320 or 737 traffic.
18,725 ft · 440 kt · squawk 7723
13,450 ft · 380 kt · squawk 4447
37,000 ft · 494 kt · squawk 2010
10,600 ft · 324 kt · squawk 1404
6,875 ft · 235 kt · squawk 4471
9,000 ft · 120 kt · squawk 7656
8,375 ft · 205 kt · squawk 1472
3,825 ft · 263 kt · squawk 4475
15,075 ft · 358 kt · squawk 1403
36,000 ft · 467 kt · squawk 5772
40,975 ft · 502 kt · squawk 6251
32,000 ft · 491 kt · squawk 0630
29,000 ft · 392 kt · squawk 3461
36,000 ft · 489 kt · squawk 7522
1,300 ft · squawk 7000
700 ft · squawk 7000
—
37,000 ft
—
36,000 ft · 465 kt · squawk 4055
13,725 ft · 291 kt · squawk 3240
32,000 ft · 478 kt · squawk 0105
—
How this is worked out
Military aircraft are flagged by the aircraft database built into the decoder, not by us guessing from hex ranges — those go stale and are wrong at the edges. Emergency squawks are the three international codes: 7500 hijack, 7600 radio failure, 7700 general emergency. In practice most are a finger slip on the transponder dial, which is worth knowing before reading anything into one.
Everything here depends on what our receivers can hear, and ADS-B is line of sight. Plenty of interesting aircraft never appear — some military traffic broadcasts nothing at all, and anything below the horizon is invisible. Running a receiver widens what this page can see.
Seen something worth keeping? The logbook records airframes by registration, so a rare visitor stays in your book permanently.