23 Apr 2012

108' 'MISCHIEF'



1881 America's Cup winner, Mischief
From a poster by Tre Tryckare, Göteborg 1962
Viewed in profile, the America's Cup defender in 1881, Mischief, was strikingly similar to Pilot Cutters from Falmouth, Britain. (Interestingly, with its clipper bow, the British challenger, Atalanta, resembled an American yacht of the time. From a distance, the tables must have appeared to be turned.)


In fact, Mishchief was nothing like the narrow, deep-draft cutters or fishing trawlers of England with their full bows and narrow sterns. She was decidedly different and rather radical, to the extent that there was nothing really like her in Europe at that time. 


Mischief was unusually beamy, of extremely shallow draft, with a centreboard, and very heavy (probably helped to a few extra tons because of the materials used - she was built of iron). The traditional craft that spring to my mind would be the catboats of New England. 
Mischief as a yacht, probably in the 1890s


From Howard Chapelle, History of American Sailing Ships 
Looking through Chapelle's History of American Sailing Ships I always admired her lines. Because apart from being beamy, shallow and shapely, with a long, efficient waterline, she had a lovely distribution of displacement - sharp forward, beamy aft. Very efficient, and in fact almost modern.


A new 'Mischief'
When I was approached a few years ago for the design of a 108' performance yacht with a traditional pilot boat character, I could think of no better inspiration than the 67' Mischief
Mischief 108' interpretation


The inefficient flat-plate centreboard is substituted for a modern bulb keel which will keep the ballast weight low. The original boat relied on a heavy displacement for its stability. With its centre of gravity pushed down, the modern version can get away with much less displacement, offering the same degree of performance as any well-designed modern cruiser / racer.
Mischief 108' interpretation












The rig shown is more for illustration purposes - on a 100' hull, such a gaff rig would be rather impractical. Mischief has not yet been built.






The new Mischief is does not pretend to be a replica, but a modern interpretation, inspired by the original. She is much larger,  with very different hull and appendages configuration, deck layout, interior layout and even aesthetics. The preferred building material would be a carbon composite.


The original seems to have been painted black in 1881 and later repainted white, for example in the photo above which I believe could have been taken in the 1890s. 


With a sail area of 550 square metres, the sail area / displacement ratio (SA /D) will be the same highish 26,4 for both boats. However, the displacement / length ratio (D /L) will be a high 349 for the old boat and a very low 109 for the modern variant. This means the two boats will have completely different sets of characteristics. 


Dimensions original Mischief             new Mischief
L.O.A.:          20.57 m                            32.80 m     
L.W.L.:          18.59 m                            29.10 m
Beam:            6.00 m                              9.00 m
Draft:             1.62 m (centerboard up)     3.50 m
Displacement: 79.2 tons                             95 tons
Sail area:       487 m2                              550 m2
SA /D             26,4                                  26,4
D /L                349                                   109