HMNZS Canterbury History
The RNZN HMNZS Canterbury is a Leander Class Frigate built in Scotland for the Royal New Zealand Navy and commissioned in 1971. She was powered by two steam turbines developing 30,000 horsepower through twin shafts. HMNZS Canterbury was the last steam powered Frigate in service.
F421 was decommissioned by the RNZN in 2005. Like most of the warships before her, she has been sunk as a diving attraction. After the popularity of the Green Peace Rainbow Warrior dive attraction further north in Matauri Bay, F421 is attracting divers from all parts of the world to dive on her at Deep Water Cove in New Zealand’s Bay of Islands.
Extensively modernized from the 1980’s. The sensors listed below were those fitted to the vessel at the time the vessels were withdrawn from service
Air Search Radar – Signaal LW-08 D Band: Range 265km for 2m2 Target
Air Surface Search Radar – Plessey Type 993 E/F Band
Navigation Radar – Kelvin Hughes Type 1006 I band
Hull Sonar – Graseby Type 750 Medium Frequency Active
Electronic Surveillance – Argo Phoenix intercept and Jammer, Telegon PST 1288 HVU
IFF system: Cossor Mk XII
Data System – Plessey/Marconi Nautis F with Link 11
Weapons Control – RCA TR-76 I Band
Guns – 2 x 1 Vickers 114mm Mk 6 – 20rpm to 19km, 1 x Phalanx CIWS – 3000 rpm to 1.5km, 4 x 12.7mm
Missiles – Seacat Missile system removed early 1990’s and replaced by Phalanx.
Anti Submarine – Mk 46 Mod 5 ASW torpedo in Mk 32 Tubes
Helicopter Launched M46 Mod 2 ASW torpedo
Maverick AGM-65 (NZ) Air to surface missile
M-60 Machine Gun
Countermeasures – 2 SRBOC Mk 36 Mod 1 launchers
The Canterbury propellers are a UK MOD design, manufactured by Stone Manganese, a large propeller design and manufacturing specialist.
The propellers are made of an aluminum-bronze alloy. Leander Class frigates pioneered ‘agouti drillings’ which were cast into the propeller during manufacture. These allow pressurised air to be fed through the body of the propeller and out through vents in the leading edge of the individual blades. This feature reduced the prospect of cavitation thus lessening erosion and reducing underwater noise – an obvious advantage for an anti-submarine frigate.
The twin five blade propellers fitted to earlier Type 12 frigates (i.e. “Otago” and “Taranaki”) did not have this feature as they were cast solid. These propellers are “handed”, i.e. the port and starboard propellers were outward turning when the ship traveled forward.
Diameter – 12′
Pitch – 17′ 8″ @ .7 radius
Area – 79.49 sq ft
Weight – 4.8 ton
One of the propellers purchased by the Far North District Council will be donated to a local community group to be mounted as a land based memorial.