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sensors Mode-S transponder

504E88

ICAO 24-bit transponder address · allocated to Moldova

Currently assigned to ER-SMA · BOEING 737-700

Hex
504E88
Octal
24047210
Decimal
5,262,984
Country
MD
Tail
ER-SMA
Type
B737
Broadcasting now · callsign SQY7506 · 38,000 ft
Flights observed
9
Distinct callsigns
5
Country
MD
Last broadcast
17h ago

Current position

504E88 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 504E88 falls within the block assigned to Moldova (MD) by ICAO Annex 10, Volume III. Every aircraft registered in Moldova 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
SQY7503 - 3 2026-04-13
SQY7504 - 2 2026-04-13
SEU414 - 2 2026-04-13
SQY7501 - 1 2026-04-14
SEU413 - 1 2026-04-13

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-14 SQY7501 - Apr 14, 09:10 UTCApr 14, 10:35 UTC1h 25m
2026-04-13 SEU414 - Apr 13, 19:50 UTCApr 13, 20:15 UTC25m
2026-04-13 SEU414 - Apr 13, 17:10 UTCApr 13, 20:10 UTC3h 0m
2026-04-13 SEU413 - Apr 13, 12:20 UTCApr 13, 15:50 UTC3h 30m
2026-04-13 SQY7504 - Apr 13, 08:20 UTCApr 13, 10:30 UTC2h 10m
2026-04-13 SQY7504 - Apr 13, 07:55 UTCApr 13, 10:30 UTC2h 35m
2026-04-13 SQY7503 - Apr 13, 04:20 UTCApr 13, 08:15 UTC3h 55m
2026-04-13 SQY7503 - Apr 13, 03:55 UTCApr 13, 07:50 UTC3h 55m
2026-04-13 SQY7503 - Apr 13, 03:40 UTCApr 13, 04:15 UTC35m

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 ER-SMA page for operator, model, and routing details .

Mode-S 504E88 frequently asked

What is Mode-S code 504E88?
504E88 is an ICAO 24-bit transponder address. Allocated to Moldova. Assigned to ER-SMA.
Where is Mode-S 504E88 registered?
Mode-S code 504E88 is allocated to Moldova (MD). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 504E88 broadcasting right now?
Yes. Mode-S 504E88 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 504E88, octal 24047210, decimal 5,262,984.
What flights does 504E88 operate?
Mode-S 504E88 has broadcast 5 distinct callsigns, including SQY7503, SQY7504, SEU414, SQY7501, SEU413.