Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A1878A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N198SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A1878A
Octal
50303612
Decimal
10,585,994
Country
US
Tail
N198SY
Type
E75L
Broadcasting now · callsign SKW3111 · 9,100 ft
Flights observed
649
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 22:25 UTC

Current position

A1878A is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A1878A falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 20 distinct

Callsign Airline Flights Last seen
SKW3074 - 10 2026-07-06
SKW3394 SkyWest Airlines 9 2026-06-09
SKW3300 SkyWest Airlines 9 2026-07-10
SKW3299 - 9 2026-06-28
SKW3217 SkyWest Airlines 8 2026-07-22
SKW3346 SkyWest Airlines 7 2026-07-20
SKW3078 SkyWest Airlines 7 2026-06-06
SKW3480 SkyWest Airlines 6 2026-07-21
SKW3461 SkyWest Airlines 6 2026-06-06
SKW3448 - 6 2026-07-25
SKW3285 - 6 2026-07-11
SKW3105 SkyWest Airlines 6 2026-07-05
SKW3063 - 6 2026-07-13
SKW3497 SkyWest Airlines 5 2026-07-24
SKW3413 SkyWest Airlines 5 2026-07-21
SKW3343 SkyWest Airlines 5 2026-07-26
SKW3337 SkyWest Airlines 5 2026-06-07
SKW3295 SkyWest Airlines 5 2026-05-31
SKW3120 - 5 2026-07-06
SKW3106 SkyWest Airlines 5 2026-07-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 SKW3489 MRY → SAN Jul 26, 17:50 UTCJul 26, 22:00 UTC4h 10m
2026-07-26 SKW3487 SAN → SMF Jul 26, 14:40 UTCJul 26, 16:00 UTC1h 20m
2026-07-26 SKW3343 SJC → SAN Jul 26, 03:45 UTCJul 26, 05:40 UTC1h 55m
2026-07-26 SKW3082 ACT → DFW Jul 26, 00:25 UTCJul 26, 01:55 UTC1h 30m
2026-07-25 SKW3083 PDX → STS Jul 25, 21:55 UTCJul 25, 23:15 UTC1h 20m
2026-07-25 SKW3363 SFO → LAX Jul 25, 18:35 UTCJul 25, 20:00 UTC1h 25m
2026-07-25 SKW3363 SFO → LAX Jul 25, 18:33 UTCJul 25, 19:56 UTC1h 23m
2026-07-25 SKW3362 SEA → SFO Jul 25, 15:55 UTCJul 25, 16:45 UTC50m
2026-07-25 SKW3362 SEA → SFO Jul 25, 15:32 UTCJul 25, 17:19 UTC1h 47m
2026-07-25 SKW3448 - Jul 25, 13:15 UTCJul 25, 13:35 UTC20m
2026-07-25 SKW3106 SAN → SJC Jul 25, 04:40 UTCJul 25, 05:15 UTC35m
2026-07-25 SKW3280 PSP → SFO Jul 25, 02:20 UTCJul 25, 03:45 UTC1h 25m
2026-07-24 SKW3488 SJC → PDX Jul 24, 23:40 UTCJul 25, 01:25 UTC1h 45m
2026-07-24 SKW3047 DTW → ORD Jul 24, 21:30 UTCJul 24, 22:50 UTC1h 20m
2026-07-24 SKW3467 FCA → LAX Jul 24, 19:00 UTCJul 24, 20:10 UTC1h 10m
2026-07-24 SKW3450 SNA → SFO Jul 24, 16:40 UTCJul 24, 17:45 UTC1h 5m
2026-07-24 SKW3497 LAX → PDX Jul 24, 14:55 UTCJul 24, 15:50 UTC55m
2026-07-24 SKW3356 PSP → SFO Jul 24, 04:05 UTCJul 24, 05:05 UTC1h 0m
2026-07-24 SKW3248 SJC → SEA Jul 24, 01:55 UTCJul 24, 03:05 UTC1h 10m
2026-07-24 SKW3248 SJC → SEA Jul 24, 01:43 UTCJul 24, 02:49 UTC1h 6m
2026-07-23 SKW3494 SNA → SFO Jul 23, 23:10 UTCJul 24, 00:55 UTC1h 45m
2026-07-23 SKW3208 - Jul 23, 16:35 UTCJul 23, 21:30 UTC4h 55m
2026-07-23 SKW3251 - Jul 23, 14:30 UTCJul 23, 15:35 UTC1h 5m
2026-07-23 SKW3464 SFO → LAX Jul 23, 02:30 UTCJul 23, 03:35 UTC1h 5m
2026-07-22 SKW3269 SMF → LAX Jul 22, 23:40 UTCJul 23, 00:45 UTC1h 5m
2026-07-22 SKW3237 SFO → SNA Jul 22, 21:30 UTCJul 22, 22:45 UTC1h 15m
2026-07-22 SKW3347 SAN → SFO Jul 22, 19:20 UTCJul 22, 20:25 UTC1h 5m
2026-07-22 SKW3217 PDX → ONT Jul 22, 15:07 UTCJul 22, 16:58 UTC1h 51m
2026-07-22 SKW3217 PDX → ONT Jul 22, 14:55 UTCJul 22, 17:10 UTC2h 15m
2026-07-22 SKW3323 LAX → PDX Jul 22, 02:30 UTCJul 22, 04:15 UTC1h 45m
2026-07-21 SKW3369 PSP → SFO Jul 21, 21:25 UTCJul 21, 22:15 UTC50m
2026-07-21 SKW3369 PSP → SFO Jul 21, 17:40 UTCJul 21, 19:00 UTC1h 20m
2026-07-21 SKW3480 BZN → SAN Jul 21, 14:20 UTCJul 21, 16:15 UTC1h 55m
2026-07-21 SKW3413 SJC → BOI Jul 21, 03:33 UTCJul 21, 04:34 UTC1h 1m
2026-07-21 SKW3413 SJC → BOI Jul 21, 03:20 UTCJul 21, 04:35 UTC1h 15m
2026-07-21 SKW3068 SAN → PHX Jul 21, 01:20 UTCJul 21, 02:20 UTC1h 0m
2026-07-20 SKW3221 EUG → LAX Jul 20, 23:10 UTCJul 21, 00:20 UTC1h 10m
2026-07-20 SKW3346 LAX → SFO Jul 20, 20:50 UTCJul 20, 21:40 UTC50m
2026-07-20 SKW3313 OAK → SAN Jul 20, 18:00 UTCJul 20, 19:35 UTC1h 35m
2026-07-20 SKW3320 - Jul 20, 15:30 UTCJul 20, 16:35 UTC1h 5m
2026-07-20 SKW3384 - Jul 20, 13:05 UTCJul 20, 14:10 UTC1h 5m
2026-07-20 SKW3005 SAF → DFW Jul 20, 05:40 UTCJul 20, 06:40 UTC1h 0m
2026-07-20 SKW3249 SEA → SJC Jul 20, 01:20 UTCJul 20, 03:55 UTC2h 35m
2026-07-19 SKW3250 - Jul 19, 21:35 UTCJul 20, 00:15 UTC2h 40m
2026-07-19 SKW3111 - Jul 19, 19:10 UTCJul 19, 20:25 UTC1h 15m
2026-07-19 SKW3079 - Jul 19, 16:25 UTCJul 19, 17:45 UTC1h 20m
2026-07-19 SKW3385 - Jul 19, 13:25 UTCJul 19, 13:50 UTC25m
2026-07-19 SKW3102 LAX → SFO Jul 19, 04:35 UTCJul 19, 05:00 UTC25m
2026-07-18 SKW3498 SEA → SEA Jul 18, 22:45 UTCJul 19, 02:55 UTC4h 10m
2026-07-18 SKW3087 MFR → SEA Jul 18, 20:35 UTCJul 18, 21:35 UTC1h 0m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N198SY page for operator, model, and routing details .

Mode-S A1878A frequently asked

What is Mode-S code A1878A?
A1878A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N198SY.
Where is Mode-S A1878A registered?
Mode-S code A1878A is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A1878A broadcasting right now?
Yes. Mode-S A1878A is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1878A, octal 50303612, decimal 10,585,994.
What flights does A1878A operate?
Mode-S A1878A has broadcast 20 distinct callsigns, including SKW3074, SKW3394, SKW3300, SKW3299, SKW3217.