RESTRICTED 



type of propeller guard. In small vessels provide suitable tackle to 

 change propellers at sea; in larger ships see that clocking plans are 

 available. 



2. Rudder. — Provide spare rudder assembly or temporary rudder 

 and rudder stock. Fit steel-wire pendants from each quarter to after 

 part of rudder blade; these will permit steering if the steering gear is 

 damaged, and prevent losing the rudder if unshipped. 



3. Waterfighf integrity. — Test all bulkheads, peaks, and tanks by 

 hydrostatic pressure. 



•i. Pumps and piping. — Test all sounding pipes and bilge and tank 

 pumping pipes for leaks and fractures. Check the operating condi- 

 tion of main drainage pumps, electric submersible pumps, and aux- 

 iliaries such as handy billies and P-500 pumps. Provide full allowance 

 of spare parts. Renew any hose not in good condition. Clean all 

 holds, scuppers, bilges, and rose boxes. After cleaning, take suction 

 in each bilge well for an over-all operating test. In loading cargo, 

 see that no sand, sawdust, or coal dust is introduced into the holds. 



5. Fire lines. — Test all water-releasing equipment such as mains and 

 cocks and renew any defective ones. 



6. Cargo stowage. — For free passage of water to bilges and easy 

 access to side plating in case of damage, stow cargo well away from 

 the sides and tom in position. Load the ship so that she will be 3 or 

 4 feet down b}' the stern when in the ice. If in ballast, consideration 

 should be given to the desirability of flooding the after hold most of 

 the depth of the shaft tunnel in order to immerse the rudder and 

 screws and minimize damage to them by ice. 



7. Underwater openings and projections. — Inspect all inlet and out- 

 let fittings in drydock. Remove all projections, such as scupper 

 guards and ringbolts, on the ship's sides above and below the water- 

 line; these catch ice and slow down progress. 



8. y^ooden planking. — If a wooden vessel is exposed to conditions 

 where water freezes around her, the ice will adhere to the calking in 

 the seams and pull it out, causing bad leaks. The preventive is to 

 apply a second layer of uncalked wooden sheathing, breaking joints 

 with the main bottom planking, with fastenings that penetrate only 

 part way through the latter. This sheathing will also protect the 

 bottom against the scoring action of ice along the water line. Fresh 

 water ice, such as is found in river mouths, is harder than sea ice 

 and is particularly severe in scoring action. Wooden vessels that 

 operate in such waters are frequently sheathed with sheet steel along 

 the water line, well nailed both through the middle of the sheets and 



RESTRICTED 43 



