818 



HYDRODYNAMICS IN SHIP DESIGN 



Sec. 76.33 



(g) Motor lifeboat Insulinde, Zeit. des Ver. Deutsch. Ing., 

 13 Apr 1929, pp. 499-503; WRH, 22 Apr 1930, pp. 

 165-166 

 (h) Ghiradi, L., "Moyens de sauvetage modemes (Modem 

 Methods of Lifesaving)," ATMA, 1932, Vol. 36, 

 pp. 83-104 

 (i) "Improved Design of Royal National Lifeboat 

 Institution Lifeboats," SBSR, 15 May 1947, pp. 

 482^83 

 (j) "The German Lifeboat Service," SBSR, 5 Jun 1947, 



pp. 556-557 

 (k) Self-righting, non-sinkable Coast Guard lifeboat is 



illustrated in USNI, Dec 1948, p. 1552 

 (1) Attwood, E. L., Pengelly, H. S., and Sims, A. J., 

 "Theoretical Naval Architecture," 1953, pp. 

 181-183 

 (m) "German Lifesaving 'Cruisers'," SBSR, 13 Jan 1955, 

 pp. 41-43. This well-illustrated paper describes the 

 newest types of German lifesaving "cruisers" for 

 rescue work. These craft are "of a larger, faster, 

 and more powerful t3rpe than previously used." 

 The Bremen is a converted steel huU having an 

 overall length of 57.42 ft, a beam of 13.75 ft, and 

 draft of 4.58 ft. The brake power is 2 times 120 horses; 

 the top speed is 11 kt. 



The first of the larger boats built expressly for 

 rescue work is the Helgoland. It has an overall length 

 of 73.75 ft, a beam of 17.75 ft, and a draft of 4.75 ft. 

 The brake power is 2 times 300 horses and the de- 

 signed top speed is 20 kt. 



Each of these rescue craft carries a smaller or 

 "daughter" boat in an inclined trough set in the 

 stem, enabling the smaller boat to be launched and 

 hauled aboard at will. The "daughter" boat is 16.42 

 ft long and 6.5 ft wide. 



Although the righting arms are large when the 

 boats are incUned to 90 deg, apparently neither of 

 them are intended to withstand rolling completely 



over and righting themselves, as for the smaller life- 

 boats. 



The two propellers of the Bremen are carried in 



side tunnels. There is one balanced rudder abaft each 



propeller with its lower pintle carried by a skeg bar 



which serves as a guard for both propeller and mdder. 



Between the port and starboard skeg bars there is 



mounted a horizontal hydrofoil which serves as a 



trim-control device to depress the stem of the larger 



craft when it is desired to launch or to take aboard 



the smaller one. 



(n) A further discussion of British and German lifeboats 



for sea-rescue work, of the period 1954-1955, is 



given by G. Wood in SBSR, Int. Des. and Equip. 



No., 1955, pp. 67-68. The new British Coverack 



class are 42.5 ft long, with twin screws driven by 



diesel engines, having a range of 238 miles at 8.38 kt. 



(o) "The Future of the R.N.L.I. Lifeboat," SBSR, 30 



Jun 1955, pp. 828-829. This article discusses a 



number of requirements and features for lifeboat 



design and indicates the probable future trends 



for British lifeboats in particular and all lifeboats 



in general. 



(p) "Fast German Rescue Ship (Herman Apelt)," SBSR, 



25 Aug. 1955, p. 259 (illustration). Length, 66 ft; 



beam, 15 ft; speed, 17 kt. 



(q) "A New Watson Class R.N.L.I. Lifeboat," The 



Motor Boat and Yachting, Feb 1956, pp. 62-63. 



76.33 Special-Purpose Craft of the Future. 



No one can predict the uses, not now dreamed of, 

 to which water craft will be put in the future. 

 It is certain, however, that the creation of new 

 forms or the adaptation of existing forms to these 

 uses is to be done most efficiently by the applica- 

 tion of hydrodynamic knowledge, as has been the 

 aim in this book. 



