Prickers to clear the test cocks had been provided but they were not used.

"There was a trickle from the test cock in number 4 tube," Hansen objected.

First of all George opens the test cock in the rear door, which will show if there is any water at all in the tubes.

Lieutenant Frederick Woods, the torpedo officer, opened the test cocks on the tubes.

Four test cocks are installed to allow an inspector to verify proper operation of the valve with a differential pressure meter.

Often, test cocks (very small ball valves) are in place to attach test equipment for evaluating whether the double check assembly is still functional.

Unfortunately, the test cock on tube number 5 was blocked by some enamel paint so no water flowed out even though the bow cap was open.

PVBs usually have test cocks, to which specially-calibrated gauges are attached, in order to ensure that they are functioning properly.

If the test cock shows nothing, then he opens the door and shines his light up to examine the bow cap and see that there is no obstruction in the tube.

This gauge uses hoses attached to the various test cocks of the RPZ and checks to be certain that the check valve springs as well as the relief valve spring are not fouled and are working properly.

Interlocks prevent the doors at both ends being opened at the same time but the inner door is also provided with a test cock to check whether the tube is full of water before opening and remains held nearly closed by the swing bolt after the locking ring is released.

The cause of the loss of Thetis was also used in the 1968 film Ice Station Zebra, where the character played by Patrick McGoohan describes a method of sabotaging a submarine by blocking the tube test cocks, allowing the inner door to be opened with the outer door also open.