A Fairly Comprehensive Review of Merlin Rocket Designs

Ian Proctor Designs
Between 1952 and 1968, Ian Proctor's designs won 14 National Championships and tied for another.  Restless 1V, the boat which won the Championships twice, (is now over 30 years old and is still sailed competitively on the river) was on display at the London Boat Show in Jan 1993.  Restless 1V was there as part of a commemoration of Ian Proctor who died in 1992.

Ian's most successful designs show trends towards finer bows, greater overall beam, and a reduction in keel rocker near the bows.  He was reluctant to experiment as far as some of the later designers did, and all but the last of his designs are narrow by today's standards.  Mainly because of this narrowness, most of these designs are now considered to be suitable only for restricted water.
Proctor designs are still capable of winning in some conditions and can do very well at river sailing clubs.  The many examples available to the second-hand market offer a good introduction to the Merlin Rocket Class.  They are very easy to sail.

Mark II 1951
This had a slimmer bow and finer shoulders than other designs of the time.  The Mark 11 gave Ian Proctor victory in the 1952 Championships at Poole.

Mark VI 1954
A stable and easily sailed design.  Not in itself a fast tacking boat, but it can be paddled around quickly enough in light airs with a rudder of the shape common twenty years ago.  Full bowed and very narrow by modern standards.  This design won the 1954 and 1956 Championships.

Mark IX 1956
The best known and most successful of all Ian Proctor's designs.  A long slicing bow and a flat run gave it ability through waves in light winds and excellent planing performance in stronger winds.  In its early years, this design had a reputation for being difficult to handle and it did not become popular until several years after it first appeared.  This design won six Championships (1957, 1958, 1960, 1961, 1963, 1966) and shared the 1965 Championship.

Mark IXb
A wider version of the Mark IX and therefore better in strong winds.  With the wider flares of the

topsides carried back to the transom, the turn of the bilge is softer than in the Mark IX.  This was felt to have improved tacking speed and stability when planing.  This design won the Championships in 1967 and 1968.  The most popular design of the mid 60's.  Very easy to handle.

Mark IXc 1966
A wider version of the IXb.

Mark XI 1958
A development of the Mark IX, with a more rounded transom and stern sections.  Probably not as fast as the IX on open water or in a blow.  This design won the 1959 Championships.

Mark XII 1959
This design was intended primarily for inland water with particular emphasis on light weather performance.  It rolls a bit on a dead run so keep the board down in a blow.   It is also good through waves in light airs.  It won the Silver Tiller several times and the Championships in 1964.

Mark XV 1962
This design was a breakaway from the slim bows of Marks IX, XI and XII.  An experiment intended to improve heavy weather stability and performance.  In achieving this, it sacrifices windward ability through a chop.

Mark XVI 1964
This design was a compromise between the Mark XII and the XV in order to combine speed through choppy water and in light airs, with stability in the blow.

Mark XVII 1969
An experiment with a wider, flatter hull shape.  This design proved fast in planing conditions, especially for light crews.  With a beam of six feet (1.83 metres) it is still competitive in club racing.

Mark XVIII 1974
The widest Proctor design.  Only one example was built.

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Bob Hoare Designs
Usually thought of as a builder rather than a designer, Bob Hoare has produced many modifications of designs by more widely recognised designers, as well as one or two of his own.  He is also a past Champion (1960) of the Merlin Rocket Class.