HMS Defender

At 10,129 gross tons, HMS Defender is the 35,530th 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 1.7 times the typical vessel on record here. The largest measures 499,167 GT.

Among the 611 naval / patrols held here, it ranks 45th by tonnage — larger than 82% of that group. Their median tonnage is 1,325 GT, and the largest tenth begin at 23,606 GT. The flag most often flown by this group is United States (136 ships). The yard that appears most often against it is Austal, with 33 hulls on record.

HMS Defender was built in 2011, making it 15 years old. It is one of 2,848 hulls in this registry delivered that year, a cohort whose median tonnage is 23,456 GT; within it this ship is the 1,802nd largest. Across the whole of the 2010s the registry holds 20,111 vessels, median 23,456 GT. The median build year across the entire registry is 1995.

The registry attributes 9 vessels to BAE Systems Maritime – Naval Ships, with a median tonnage of 2,500 GT, delivered between 1999 and 2020. See the rest of that yard’s output.

At 152.4 m overall, HMS Defender is 65.9 m longer than the 86.5 m median for naval / patrols on record, with a beam of 21.2 m and a draft of 7.4 m.

IMO numbers are issued in broadly chronological blocks. Within 500 either side of 4907878 this registry holds 10 other vessels, whose median build year is 2010 and which range from 1994 to 2020. That places this hull’s registration in the same part of the series, consistent with its recorded build year of 2011.

Its IMO number, 4907878, carries its own check digit. The first six digits are weighted seven down to two and summed — 4×7 + 9×6 + 0×5 + 7×4 + 8×3 + 7×2 = 148 — and the last digit of that total, 8, must equal the seventh digit, 8. It does, so this number is well formed.