Many of a Hunt Class’s mine-hunter’s hull-design characteristics are based on the requirement for it to accurately hold position at sea whilst prosecuting mines. Relatively large propellers & rudders, a bow-thruster, a rounded hull form & shallow draft all assist with this. These same characteristics also mean that it can ‘walk’ sideways during berthing and unberthing. A neat trick that can get you in and out of tight spots when required.
The principle of walking is simple, the execution, sometimes less so. In this instance you need to exit to the West and therefore:
1. Set bow-thruster to port (full)
2. Use a combination of main engines and rudders to provide counter-torque:
2a. Port ME ahead (slow)
2b. Stbd ME astern (half-ish)
2c. Rudders to stbd (xx degrees)
3. Get all this in balance and the ship should walk laterally to port.
4. Never forget ceremonial…
That’s the theory. As with everything maritime, it’s never quite that simple:
1. Because everything is in balance, if something changes (wind/tide/system fail) you can quickly run out of escape options.
2. You need to set up ‘the balance’ from the start of the manoeuvre. For example, the fwd engine/prop (2a) bites like your car with no synchromesh – if that happens too early, you’ll surge forward (bad). Timing is key.
3. The Hunt’s high sides, shallow displacement and rounded hull make them excellent sailing vessels. Any more than c.8kts of wind and your set up will need to be adjusted.
4. Compared to normal berthing/unberthing, ‘walking’ is quite slow.
But if you get it just right; everything nicely balanced, no fwd or aft movement (at all for bonus points!) and with precision control of the ships head using just the rudder, then you can get in and out of tight spaces, exit in a smart and seamanlike manner and show general cunning to your destroyer mates as they wait for yet another tug.
Footnote: a Sandown Class mine hunter can do all this at the touch of a button which is why they’re not to be trusted.
Second footnote: these are the kind of ship-handling skills that an automated mine-hunting force will not provide the commanders of tomorrow.
Commander Tom Sharpe OBE (Retd) was assigned to three Hunt Class mine sweepers in his career; HMS Chiddingfold as a Young Officer, HMS Brocklesby as a Junior Watchkeeping Officer and HMS Dulverton as the Captain (on Northern Ireland duties).