A public reference property of Baalvion

Open data · every figure carries its source

World Shipping DirectoryCompanies · Ships · Fleets

A public reference property of Baalvion

Open data · every figure carries its source

World Shipping DirectoryCompanies · Ships · Fleets

Research / survey

Otso

IMO 8405880MMSI 230252000Call sign OIRTFinlandBuilt 1986

Operator on record: Finnish Maritime Administration (1986–2004)

Photo: Jukka Koskimies · CC BY-SA 3.0 · file

Largest in this registry

#40,187

of 84,014 with a recorded tonnage

Largest research / survey

#69

of 483 of this type with a recorded tonnage

Fleet rank

—

No operator attributed to this ship

In brief

About Otso

Full article ↗

Otso is a Finnish state-owned icebreaker. Built by Wärtsilä Helsinki shipyard in 1986 to replace the aging Karhu-class icebreakers, she was the first Finnish post-war icebreaker to be built without bow propellers. Otso has an identical sister ship, Kontio, which was delivered in 1987.

Quoted from Otso (icebreaker) on English Wikipedia, reused under CC BY-SA 4.0.

Vessel particulars

Identification and dimensions

Every value is as recorded in the source. Blanks are values the source does not hold — none is estimated from a sister ship or a class average.

Identification

IMO number

In context

How Otso compares

Every figure in this section is a count, a rank or a percentile over vessels actually held in this registry — not over the world fleet, which is larger. Nothing here is estimated.

At 7,066 gross tons, Otso is the 40,187th largest of the 84,014 vessels in this registry that report a tonnage. The median across that set is 5,994 GT, so this hull is about 1.2 times the typical vessel on record here. The largest measures 499,167 GT.

Among the 612 research / surveys held here, it ranks 69th by tonnage — larger than 86% of that group. Their median tonnage is 2,180 GT, and the largest tenth begin at 9,452 GT. The flag most often flown by this group is United States (90 ships). The yard that appears most often against it is Wärtsilä, with 36 hulls on record.

Finland is the country of registry for 249 vessels in this directory, of which Otso is the 75th largest by tonnage. The most common class under that flag is vessels this registry holds no type classification for (110 ships), and the median vessel measures 2,673 GT. Browse every ship flagged Finland.

Narrowing to both dimensions at once, this registry holds 16 research / surveys flying the Finland flag, of which 5 are larger by tonnage.

Otso was built in 1986, making it 40 years old. It is one of 866 hulls in this registry delivered that year, a cohort whose median tonnage is 4,769 GT; within it this ship is the 371st largest. Across the whole of the 1980s the registry holds 13,213 vessels, median 3,004 GT. The median build year across the entire registry is 1995.

The registry attributes 118 vessels to Wärtsilä, with a median tonnage of 14,058 GT, delivered between 1938 and 1998. See the rest of that yard’s output.

At 98.6 m overall, Otso is 27.6 m longer than the 71.0 m median for research / surveys on record, with a beam of 24.2 m and a draft of 8.0 m.

IMO numbers are issued in broadly chronological blocks. Within 500 either side of 8405880 this registry holds 43 other vessels, whose median build year is 1985 and which range from 1983 to 1989. That places this hull’s registration in the same part of the series, consistent with its recorded build year of 1986.

Its IMO number, 8405880, carries its own check digit. The first six digits are weighted seven down to two and summed — 8×7 + 4×6 + 0×5 + 5×4 + 8×3 + 8×2 = 140 — and the last digit of that total, 0, must equal the seventh digit, 0. It does, so this number is well formed.