AIS ship and cargo type · Wing-in-ground (WIG) craft
AIS ship type 20: Wing-in-ground (WIG) craft
Ship type 20 is the wing-in-ground (wig) craft family with no cargo declaration. What it means, what it does not, and how many vessels we can hear sending it right now.
What code 20 means
Wing-in-ground craft fly a few metres above the surface on the cushion of air trapped between a wing and the water. They are rare in service. Because the craft are rare, a 2x code on what is plainly an ordinary hull is worth reading as a likely configuration error rather than as a WIG craft.
A units digit of 0 is the plain family code with no cargo declaration attached. It is the most common way the family is reported.
Reading the two digits
- Tens digit 2 → the wing-in-ground (wig) craft family, codes 20–29.
- Units digit 0 → all ships of this type.
- Therefore: Wing-in-ground (WIG) craft.
Every code in the 20–29 range
| Code | Meaning |
|---|---|
| 20 | Wing-in-ground (WIG) craft |
| 21 | Wing-in-ground (WIG) craft, hazardous category A |
| 22 | Wing-in-ground (WIG) craft, hazardous category B |
| 23 | Wing-in-ground (WIG) craft, hazardous category C |
| 24 | Wing-in-ground (WIG) craft, hazardous category D |
| 25 | Wing-in-ground (WIG) craft, reserved |
| 26 | Wing-in-ground (WIG) craft, reserved |
| 27 | Wing-in-ground (WIG) craft, reserved |
| 28 | Wing-in-ground (WIG) craft, reserved |
| 29 | Wing-in-ground (WIG) craft, no additional information |
What the code is not
The ship-and-cargo type is typed into the transponder by whoever installs or operates it. No authority checks it against the ship’s certificates, and it is broadcast in the static report every six minutes whether or not it is right. It describes what the operator says the vessel is, not what it is doing — that is the job of the navigational status.
For the whole decade structure in one read, see AIS ship type codes explained.