Completing a Light Jackstay Transfer
In the image above, the individual in the vivid orange survival suit, with fully-inflated lifejacket, dangles from a strop between two warships travelling on a parallel course about 100 feet apart. He is about to be collected by one of Nottingham's crew. He is part of a demonstration, showing a large array of spectators aboard HMS Nottingham (some of whom can be seen on the bridge wing and lounging aft of the missile system) how to transfer personnel quickly between ships whilst remaining underway (and without the expense of firing up the petrol pigeon [helicopter] on the stern!).
The light jackstay is the rope upon which he and everything around him is suspended. This is normally a four-inch manila rope, which has been passed across from us to Nottingham and tensioned before he is suspended from the traveller block, which is the metal feature that is running along the manila rope.
Of the two lower ropes attached to the traveller, the one on the left is the inhaul, which is used by us to pull the traveller back to us after the transfer is completed, either to stow the rig or to commence another transfer. The lower rope on the right is the outhaul. It is the means by which the individual is being pulled across to Nottingham. Manpower is the entire motive power in this evolution.
A key skill in this evolution is ensuring the gap between the ships remains as steady as possible during the evolution. If they get too close, the jackstay sags and the individual may get his feet (or more!) wet. There is also the risk of the ships being affected by fluid dynamics which effectively results in them being affected by the flow of water between them and being sucked together, resulting in their sides colliding.
If one of the ships loses power or steering during an evolution like this, both ships have practiced emergency procedures for cutting away the ropes and the one still with power/steering turning away to avoid the uncontrollable vessel. This might result in the individual being transferred ending up in the water on his own, leading to a man-overboard situation...
This demonstration was conducted during the 1986 Staff College Sea Days in the English Channel, where the students at the Army, Navy and Air Force Staff Colleges got a day at sea to see all sorts of evolutions and activities aboard warships.
The missile system on Nottingham's focsle is, of course, the Hawker Siddeley Dynamics GWS30 Sea Dart medium-range SAM, probably a Mod 1 variant, which (according to Wikipedia) had an operational range of some 74 km, theoretical ceiling of 10,000m and a top speed of Mach 2+. The blue booster is clearly visible.
Scanned from a negative.
Completing a Light Jackstay Transfer
In the image above, the individual in the vivid orange survival suit, with fully-inflated lifejacket, dangles from a strop between two warships travelling on a parallel course about 100 feet apart. He is about to be collected by one of Nottingham's crew. He is part of a demonstration, showing a large array of spectators aboard HMS Nottingham (some of whom can be seen on the bridge wing and lounging aft of the missile system) how to transfer personnel quickly between ships whilst remaining underway (and without the expense of firing up the petrol pigeon [helicopter] on the stern!).
The light jackstay is the rope upon which he and everything around him is suspended. This is normally a four-inch manila rope, which has been passed across from us to Nottingham and tensioned before he is suspended from the traveller block, which is the metal feature that is running along the manila rope.
Of the two lower ropes attached to the traveller, the one on the left is the inhaul, which is used by us to pull the traveller back to us after the transfer is completed, either to stow the rig or to commence another transfer. The lower rope on the right is the outhaul. It is the means by which the individual is being pulled across to Nottingham. Manpower is the entire motive power in this evolution.
A key skill in this evolution is ensuring the gap between the ships remains as steady as possible during the evolution. If they get too close, the jackstay sags and the individual may get his feet (or more!) wet. There is also the risk of the ships being affected by fluid dynamics which effectively results in them being affected by the flow of water between them and being sucked together, resulting in their sides colliding.
If one of the ships loses power or steering during an evolution like this, both ships have practiced emergency procedures for cutting away the ropes and the one still with power/steering turning away to avoid the uncontrollable vessel. This might result in the individual being transferred ending up in the water on his own, leading to a man-overboard situation...
This demonstration was conducted during the 1986 Staff College Sea Days in the English Channel, where the students at the Army, Navy and Air Force Staff Colleges got a day at sea to see all sorts of evolutions and activities aboard warships.
The missile system on Nottingham's focsle is, of course, the Hawker Siddeley Dynamics GWS30 Sea Dart medium-range SAM, probably a Mod 1 variant, which (according to Wikipedia) had an operational range of some 74 km, theoretical ceiling of 10,000m and a top speed of Mach 2+. The blue booster is clearly visible.
Scanned from a negative.