LAUNCHING OF SHIPS IN RESTRICTED WATERS. 23 
on the floor of the slip so that each chain was clear of the others and separated 
from its own parts. The tumbling shores, of course, had to remain until the vessel 
was released, and, although they were directly in the path of the chains, there was 
no interference and very few of the timbers were thrown about. 
“From the moment that the vessel was released until she reached 648 feet 
travel, everything functioned exactly as was planned. At about 560 feet travel 
the chain cables began to straighten out, and at about 570 feet travel the klaxon 
signal was given to apply normal pressure on Nos. 3, 4 and 5. Within less than 
one-half second the operators began pumping on these brakes, and the first appli- 
cation of pressure was sufficient to straighten out the chain cables. The brakes 
smoked considerably from the start, due to the fact that there was a protective 
coating on the wire cables of some fish oil preparation, which burned off on the 
outside of the strands as soon as the cables began to slide. At about 620 feet 
travel the cables straightened out on No. 1 and No. 2 brakes, and normal pressure 
was applied by the operators. 
“At 648 feet travel, after the wires on No. 3 port brake had gone about 80 
feet through the blocks and a pressure of 500 to 600 pounds per square inch had 
been applied to the rams, the chain cable on that brake carried away several feet 
from the pad on the ship’s side. The vessel by this time had left the ways and was 
traveling at a velocity of about 1914 feet per second. At 660 feet travel, the 
chain cable on No. 5 port brake carried away about 420 feet from the ship’s side. 
The wire cables and the cable reels, traveling at high speed when the wires sud- 
denly stopped in the brake, possessed enough momentum to throw the wires up 
in kinks behind the brake and to unwind several turns from the reels. Although 
the friction brakes on the cable reels were not supposed to care for such a sudden 
stoppage, they should properly have been set to exert considerably more resist- 
ance (see Plate 8). 
“One by one, as the pressure on the brakes was increased, their respective 
cables parted, about half of the chains remaining intact when normal pressure 
was obtained. At 776 feet travel, all chains except No. I port had parted; at 
780 feet, one of the links connecting the outside wire on No. 1 carried away and 
the inside wire continued to pull through the brake. Although no further signal 
was given at this time from the control station, the supervisor in charge on the 
port side motioned to the operator at No. 1 to hold the pressure on his brake. 
Mistaking this for a signal to apply emergency pressure, he immediately began 
pumping to about 1,100 pounds per square inch. At 902 feet travel, as soon as 
this pressure had been applied, this chain cable also parted and the vessel was 
then running freely with the exception of the pieces of chain dragging along from 
the pad-eyes. The starboard and port anchors were then dropped and the vessel 
brought to rest as described elsewhere in this report. 
“Port No. 4 brake was dismantled and opened for inspection immediately 
after the launching. The wires had traveled about 100 feet through the blocks, 
but there was no rifling and comparatively little scoring of the grooves. The 
leading end of the grooves showed practically no wear; the trailing end showed 
