Manoeuvrability and Propulsion of Very Large Tankers 



Table 4 

 Results of Resistance and Self-Propulsion Tests in Loaded Condition 



Table 6 compares the results of the EHP and SHP tests run at the loaded 

 condition of the conventional model and the model with the Hogner-type stern 

 with nozzles Nos. 1, 2, or 3. Table 7 compares the results at the light condition. 



From the tables, it may be concluded that the extremely cigar-shaped 

 afterbody is favourable from a viewpoint of resistance. The EHP of the model 

 with the extremely cigar -shaped afterbody is about 1 percent less in the loaded 

 condition and 5 percent less in the light condition, compared with the conven- 

 tionally shaped model. 



It is worth noting that this conclusion is contrary to cigar -shaped sterns 

 investigated up till now. The tanker with the Hogner-type stern and nozzle No. 

 1 fitted, requires less power than the Hogner-type stern with nozzles No. 2 and 

 No. 3 and the conventional stern. The Hogner-type stern with nozzle No. 1 

 fitted requires about 6 percent less SHP in the loaded condition and 9 percent 

 less SHP in the light condition, than the conventionally shaped stern. 



253 



