sensors Mode-S transponder

AC1698

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N8781Q · BOEING 737 MAX 8 · operated by SOUTHWEST AIRLINES CO

Hex
AC1698
Octal
53013230
Decimal
11,277,976
Country
US
Tail
N8781Q
Type
B38M
Broadcasting now · callsign SWA3033 · 32,000 ft
Flights observed
10
Distinct callsigns
5
Country
US
Last broadcast
12h ago

Current position

AC1698 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address AC1698 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 5 distinct

Callsign Airline Flights Last seen
SWA9000 - 3 2026-04-13
SWA3840 - 3 2026-04-13
SWA658 - 2 2026-04-13
SWA208 - 1 2026-04-14
SWA1705 Southwest Airlines 1 2026-04-13

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-14 SWA208 - Apr 14, 10:20 UTCApr 14, 11:05 UTC45m
2026-04-13 SWA658 - Apr 13, 21:35 UTCApr 13, 22:45 UTC1h 10m
2026-04-13 SWA658 ORD → ORD Apr 13, 20:00 UTCApr 13, 21:12 UTC1h 12m
2026-04-13 SWA9000 - Apr 13, 16:15 UTCApr 13, 19:25 UTC3h 10m
2026-04-13 SWA9000 LAS → ORD Apr 13, 16:00 UTCApr 13, 19:25 UTC3h 25m
2026-04-13 SWA9000 - Apr 13, 15:24 UTCApr 13, 18:24 UTC3h 0m
2026-04-13 SWA1705 DAL → BWI Apr 13, 12:25 UTCApr 13, 13:20 UTC55m
2026-04-13 SWA3840 - Apr 13, 00:10 UTCApr 13, 00:20 UTC10m
2026-04-12 SWA3840 MSY → MDW Apr 12, 18:04 UTCApr 13, 00:20 UTC6h 16m
2026-04-12 SWA3840 MSY → MDW Apr 12, 17:57 UTCApr 12, 23:57 UTC6h 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 N8781Q page for operator, model, and routing details .

Mode-S AC1698 frequently asked

What is Mode-S code AC1698?
AC1698 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N8781Q.
Where is Mode-S AC1698 registered?
Mode-S code AC1698 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 AC1698 broadcasting right now?
Yes. Mode-S AC1698 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC1698, octal 53013230, decimal 11,277,976.
What flights does AC1698 operate?
Mode-S AC1698 has broadcast 5 distinct callsigns, including SWA9000, SWA3840, SWA658, SWA208, SWA1705.