Effective Strategy
The next patrol, which occurred in February 1943 did not see many accomplishments, in part because of a newly added radar. The Grayback made it to the end of her seventh tour, which began on April 25th, 1943 in Brisbane.
A Second Award
When the Grayback left Brisbane she managed to hit the merchant ship Yodogawa Maru and sank her. This was not the only successful mission she carried out, but just two days later the U.S. vessel torpedoed an enemy, and the following day the Grayback sank another ship called the England Maru.