James Bond Stockdale (December 23, 1923 - July 5, 2005) was a United States Navy vice admiral and aviator awarded the Medal of Honor in the Vietnam War, during which he was a prisoner of war for over seven years. Commander Stockdale was the senior naval officer held captive in Hanoi, North Vietnam. He had led aerial attacks from the carrier USS Ticonderoga (CVA-14) during the 1964 Gulf of Tonkin Incident. On his next deployment, while Commander of Carrier Air Wing Sixteen aboard the carrier USS Oriskany (CV-34), his A-4 Skyhawk jet was shot down in North Vietnam on September 9, 1965.

On June 5, 1946 he graduated with a Bachelor of Science degree from the Naval Academy with the Class of 1947 due to the reduced schedule still in effect from World War II. Academically he ranked 130th among 821 graduates in his class. His first assignment was assistant gunnery officer aboard the destroyer minesweeper USS Carmick (DD-493) from June to October 1946. He next served aboard the USS Thompson (DD-627) from October 1946 to February 1947, the USS Charles H. Roan (DD-853) from February 1947 to July 1948, and the USS Deming (PCS-1392) from July 1948 to June 1949.  Stockdale was accepted for flight training in June 1949 and reported to Naval Air Station Pensacola in Florida. He was designated a Naval Aviator at Naval Air Station Corpus Christi in Texas, in September 1950. He was next assigned for additional training at Naval Air Station Norfolk in Virginia from October 1950 to January 1951. In January 1954, he was accepted into the United States Naval Test Pilot School at the Naval Air Station Patuxent River base in Southern Maryland and completed his training in July 1954. There he tutored U.S. Marine Corps aviator John Glenn in math and physics. He was a test pilot until January 1957.  In 1959, the U.S. Navy sent Stockdale to Stanford University where he received a Master of Arts degree in international relations and comparative Marxist thought in 1962. Stockdale preferred the life of a fighter pilot over academia, but later credited Stoic philosophy with helping him cope as a prisoner of war.

Using a quote from the above article, answer the following question: what did he test?
There he tutored U.S. Marine Corps aviator John Glenn in math and physics. He was a test pilot until January 1957.