Saturday, 21 April 2012

April 21 1982

Log book entry: GWS 25 Cals, 1 Hour.   AARgghhh! Not my favourite sortie.

GWS25 = Gunnery Weapon System 25 in other words Sea Wolf. What a fantastic system - it was brought in as the replacement for the old visually aimed Sea Cat which was well past its sell by date. Someone was getting naval technology right in the early eighties because this and the new Stingray torpedo (more another time) were world beaters. They probably still are. Andromeda was the first Leander to get Sea Wolf so we got do quite a lot of live firings early on in our commission. The system worked by detecting targets with a Doppler and area radar (967/968). This meant the faster the target was going, the easier it was to detect. It then handed the target over to a high frequency fire control radar (910) which guided the weapon onto the target. The missile itself launched with a hell of a bang as the rocket motor only fired very briefly, propelling the missile to multiple supersonic speeds. It then 'coasted' to the target where it blew it to bits. As an alternative, if the 910 radar couldn't acquire, there was a TV camera mounted on top of it and an aimer in the operations room only had to track the target for the missile to home on to it. We used to check it out by getting another ship to fire her 4.5 inch gun ahead of us and the system would detect the shell and then the tracker would follow it right to when it splashed into the sea. I remember a conversation with a Yank naval officer friend in Baltimore who flatly refused to believe me until we showed him the TV recordings. It was very short range but as a point defence weapon absolutely fantastic. Unfortunately it could pick up the leading edge of ARFA's rotor blades. They made a very nice potential target as they were travelling so fast. We used to be a tad careful when returning to the ship during the war when the system was live. It didn't need a command to fire. It would detect, prioritise and shoot down targets all on its little lonesome unless the Command overrode it - bit scary really! The other minor downside was that the radars weighed 6 tons and were on top of a tall mast - Andromeda rolled. But hey you get used to these things. It was only when we visited other frigates that were barely moving that we realised how much fun deck landings on our own ship were!

So why weren't 'Cals' my favourite sortie?  Well 'Cals' means calibrations and we did them by fitting a big electronics thingy inside the cabin of the aircraft which looked out of the starboard door. We then hovered at four hundred feet about a quarter of a mile away while the engineers on the ship did their thing whatever it was, to align the whole system. Hovering at that height and distance is bloody difficult as everything is just a little too far away. Helicopter pilots like to be able to judge what the aircraft is doing so they can correct things. An hour of this was very, very hard work. Mind you only a few weeks later we were rather glad to be one of only three Sea Wolf ships down south. There's nothing like having the warm fuzzy feeling that you've got the best point defence system of all.......

'Mum' early on in the commission (no Exocet yet).   The 967/968 is on top of the forward mast, all six tons of it. The 910 fire control radar is on top of the bridge and the weapon launcher is the white box like affair on the foredeck - holding 6 ready use missiles.

BANG!  you're dead.  No, no, you really are dead!

1 comment:

  1. Worked on the GWS31s GWS25s at the Vickers Shipyard in Barrow. Happy Days!