AIS Spoofing in the Red Sea: What’s Really Happening

A cargo ship off Yanbu suddenly reports a position it couldn’t possibly have reached.

Its speed jumps to 45 knots, far beyond what a loaded tanker can realistically do. Minutes later, the signal disappears. Hours after that, the vessel reappears somewhere else entirely.

If you’ve been watching AIS traffic around the Red Sea in 2026, you’ve probably seen something similar.

It isn’t necessarily a tracking-platform glitch.

The region is dealing with a mix of GNSS interference, AIS spoofing and AIS blackouts in the Red Sea, including vessels deliberately switching off AIS for security reasons. On a tracking map, all three can look similar: strange positions, impossible speeds, sudden gaps and unexplained jumps.

Spoofing and Going Dark Are Not the Same Thing:

AIS spoofing happens when a vessel broadcasts position, speed or course data that doesn’t match reality.

Often, this is caused by GNSS interference rather than someone hacking the vessel itself. If the positioning signal is wrong, the AIS transponder can still broadcast that incorrect position normally.

Typical signs include:

• impossible speeds
• sudden position jumps
• strange course changes
• vessels appearing in impossible locations

Going dark is different.

The vessel simply stops transmitting AIS.

In high-risk areas, this can be deliberate. Broadcasting a ship’s exact position, speed and course can make it easier to target.

Why Ships Are Disappearing From AIS?

Security guidance has made intentional AIS blackouts more common.

US Maritime Administration advisory MARAD 2026-006, issued in March 2026, covers areas including the southern Red Sea, Bab el-Mandeb and Gulf of Aden.

It advises US-flagged vessels to switch off AIS in certain high-risk situations when the master believes broadcasting could create a security threat.

So a vessel disappearing from a tracking screen does not automatically mean something suspicious happened.

It might be:

• deliberate AIS shutdown
• GNSS interference
• loss of terrestrial receiver coverage
• temporary communication problems

The Gap Isn’t the Most Interesting Part:

When analysing AIS data, what happens before and after a gap often tells you more than the gap itself.

Look at the vessel’s:

• last reliable position
• heading
• normal operating speed
• time offline
• position when AIS resumes

If a vessel capable of 15 knots disappears for an hour and reappears 150 nautical miles away, the track clearly doesn’t make physical sense.

Likewise, if a tanker suddenly reports 40 or 50 knots before disappearing, the vessel probably didn’t suddenly become a speedboat.

The data is more likely wrong.

What AIS Data Can and Cannot Tell You?

Historical AIS is still extremely useful.

You can see where a vessel was last detected, how it was moving, how long the signal disappeared and where it later reappeared.

But it cannot reconstruct exactly what happened during a blackout.

Datalastic uses a network of terrestrial AIS receivers, not satellite AIS. A vessel outside receiver range or with its transponder switched off will naturally create a gap.

That matters particularly in regions such as the Red Sea, where continuous tracking should not always be expected.

The better question is not:

“Why did this vessel disappear?”

It is:

“Does the movement before and after the gap actually make sense?”

FAQ

Does AIS spoofing mean the ship was hacked?

Usually not. GNSS interference can feed incorrect position data into onboard navigation systems, which can then be transmitted through AIS normally.

Is switching off AIS illegal?

Not always. Maritime rules allow AIS to be disabled in some situations when continued transmission could compromise vessel safety or security.

Can vessels in the Red Sea still be tracked?

Yes, but expect more gaps and anomalies than in normal shipping corridors. Last known positions, historical tracks and resumption points are still useful when analysed together.

See the Track, Not Just the Dot

With the Datalastic Historical Vessel Data API, you can review previous vessel positions and identify where transmissions stop, where they resume and whether the movement between those points makes sense.

The Live Vessel Data API provides current AIS information including position, speed and navigational status.

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