sensors Mode-S transponder

AB23B5

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N817DN · BOEING 737-900 · operated by DELTA AIR LINES INC, DEPT 595 AIRCRAFT REGISTRATIONS

Hex
AB23B5
Octal
52621665
Decimal
11,215,797
Country
US
Tail
N817DN
Type
B739
No current signal · last broadcast 1h ago
Flights observed
236
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S AB23B5.

Country allocation

The ICAO 24-bit address AB23B5 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 DAL1878 CUN → MSP May 29, 19:30 UTCMay 29, 23:15 UTC3h 45m
2026-05-29 DAL1881 MSP → CUN May 29, 14:20 UTCMay 29, 18:00 UTC3h 40m
2026-05-29 DAL949 MIA → LGA May 29, 00:10 UTCMay 29, 03:10 UTC3h 0m
2026-05-28 DAL481 SEA → OGG May 28, 17:20 UTCMay 28, 21:50 UTC4h 30m
2026-05-28 DAL3091 ATL → CHS May 28, 15:00 UTCMay 28, 15:45 UTC45m
2026-05-28 DAL3091 ATL → CHS May 28, 12:35 UTCMay 28, 13:20 UTC45m
2026-05-28 DAL495 SFO → DTW May 28, 06:35 UTCMay 28, 11:00 UTC4h 25m
2026-05-28 DAL2762 SLC → SFO May 28, 03:40 UTCMay 28, 05:05 UTC1h 25m
2026-05-27 DAL1602 ORD → DTW May 27, 20:35 UTCMay 27, 23:45 UTC3h 10m
2026-05-27 DAL2236 BOS → PBI May 27, 16:00 UTCMay 27, 19:00 UTC3h 0m
2026-05-27 DAL2236 BOS → PBI May 27, 15:58 UTCMay 27, 18:57 UTC2h 59m
2026-05-27 DAL2674 LAS → SLC May 27, 13:15 UTCMay 27, 14:15 UTC1h 0m
2026-05-27 DAL2674 LAS → SLC May 27, 13:15 UTCMay 27, 14:09 UTC54m
2026-05-26 DAL544 ATL → LGA May 26, 22:44 UTCMay 27, 02:24 UTC3h 40m
2026-05-26 DAL466 JFK → LAX May 26, 17:09 UTCMay 26, 19:25 UTC2h 15m
2026-05-26 DAL466 JFK → LAX May 26, 17:05 UTCMay 26, 19:25 UTC2h 20m
2026-05-26 DAL466 JFK → LAX May 26, 12:50 UTCMay 26, 15:24 UTC2h 35m
2026-05-26 DAL407 PHL → SLC May 26, 06:39 UTCMay 26, 10:39 UTC4h 0m
2026-05-26 DAL509 BOS → LAX May 26, 00:14 UTCMay 26, 04:10 UTC3h 55m
2026-05-25 DAL3159 ATL → BNA May 25, 21:48 UTCMay 25, 22:30 UTC42m
2026-05-25 DAL3159 ATL → BNA May 25, 21:49 UTCMay 25, 22:34 UTC45m
2026-05-25 DAL640 DTW → SAN May 25, 15:45 UTCMay 25, 20:09 UTC4h 24m
2026-05-24 DAL442 LAX → SFO May 24, 20:25 UTCMay 24, 23:46 UTC3h 21m
2026-05-24 DAL772 BOS → BNA May 24, 13:00 UTCMay 24, 17:05 UTC4h 5m
2026-05-23 DAL517 ATL → BOS May 23, 21:35 UTCMay 24, 02:10 UTC4h 35m
2026-05-23 DAL1640 LAX → JFK May 23, 18:45 UTCMay 23, 19:30 UTC45m
2026-05-23 DAL1640 LAX → JFK May 23, 16:30 UTCMay 23, 17:20 UTC50m
2026-05-23 DAL1516 JFK → RSW May 23, 13:30 UTCMay 23, 15:05 UTC1h 35m
2026-05-23 DAL1139 DTW → BOS May 23, 02:25 UTCMay 23, 03:50 UTC1h 24m
2026-05-22 DAL1758 PTY → ATL May 22, 20:15 UTCMay 22, 23:35 UTC3h 20m
2026-05-22 DAL1759 ATL → PTY May 22, 14:42 UTCMay 22, 18:17 UTC3h 35m
2026-05-22 DAL1759 ATL → PTY May 22, 14:45 UTCMay 22, 17:40 UTC2h 55m
2026-05-22 DAL3114 - May 22, 11:15 UTCMay 22, 11:55 UTC40m
2026-05-22 DAL3131 - May 22, 03:36 UTCMay 22, 04:19 UTC43m
2026-05-22 DAL3131 - May 22, 03:35 UTCMay 22, 04:20 UTC45m
2026-05-21 DAL1124 RSW → ATL May 21, 23:50 UTCMay 22, 01:10 UTC1h 20m
2026-05-21 DAL1124 RSW → ATL May 21, 21:15 UTCMay 21, 22:35 UTC1h 20m
2026-05-21 DAL2925 ATL → ORF May 21, 18:20 UTCMay 21, 19:35 UTC1h 15m
2026-05-21 DAL2925 ATL → ORF May 21, 15:35 UTCMay 21, 16:50 UTC1h 15m
2026-05-21 DAL1247 HPN → ATL May 21, 12:35 UTCMay 21, 14:00 UTC1h 25m
2026-05-21 DAL1139 DTW → BOS May 21, 01:05 UTCMay 21, 02:35 UTC1h 30m
2026-05-21 DAL1139 DTW → BOS May 21, 01:06 UTCMay 21, 02:33 UTC1h 27m
2026-05-20 DAL3115 SRQ → ATL May 20, 22:10 UTCMay 20, 23:20 UTC1h 10m
2026-05-20 DAL3115 SRQ → ATL May 20, 19:40 UTCMay 20, 20:50 UTC1h 10m
2026-05-20 DAL1504 BOS → JAX May 20, 10:00 UTCMay 20, 11:10 UTC1h 10m
2026-05-20 DAL1351 SJC → ATL May 20, 03:05 UTCMay 20, 04:25 UTC1h 20m
2026-05-19 DAL1109 ATL → LGA May 19, 22:50 UTCMay 20, 01:35 UTC2h 45m
2026-05-19 DAL1109 ATL → LGA May 19, 18:35 UTCMay 19, 21:40 UTC3h 5m
2026-05-19 DAL2999 RDU → BOS May 19, 15:25 UTCMay 19, 17:00 UTC1h 35m
2026-05-19 DAL2999 RDU → BOS May 19, 12:20 UTCMay 19, 13:50 UTC1h 30m

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 N817DN page for operator, model, and routing details .

Mode-S AB23B5 frequently asked

What is Mode-S code AB23B5?
AB23B5 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N817DN.
Where is Mode-S AB23B5 registered?
Mode-S code AB23B5 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 AB23B5 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AB23B5, octal 52621665, decimal 11,215,797.
What flights does AB23B5 operate?
Mode-S AB23B5 has broadcast 20 distinct callsigns, including DAL2449, DAL809, DAL2236, DAL864, DAL772.