In 1972, it acquired 150 more powerful German pumps driven by small gas turbines.
It foamed and roared under the pressure of a powerful pump.
An alternative to a large filter is to connect two small units together, and use a powerful pump.
Some of the largest and most powerful pumps are of this kind.
But eventually these pits collected too much water and there were no powerful pumps at hand.
When pressure did not rise as expected, workers started a second powerful pump.
Once more turning on the electric current, he set the powerful pumps in motion and the submarine began to rise.
In 1972 another 150 more powerful German-made pumps were purchased.
By that time the powerful pumps would have their job completed.
As though he guessed what was in my mind, he said, 'We've very powerful pumps.