Please answer the following question: Generate a question that has the following answer: Carl Troxell for the following movie plot: Lt. Colonel Matt Brennan (Humphrey Bogart), discharged from the military, runs a civilian flying school, where he is reunited with an old US Army Air Force buddy, Major Hinkle (James Brown). Brennan is offered a job at the Willis Aircraft Company as chief test pilot for an experimental high speed jet fighter known as the JA-3, designed by Carl Troxell (Richard Whorf). Troxell is also a link to Brennan's past, having known him in the war when Brennan was a bomber pilot. A flashback to B-17 missions over Germany reveal Brennan to be a top-notch pilot. Another connection to his past is his former flame, Jo Holloway (Eleanor Parker), now Willis' secretary. In order to prove the capabilities of the new JA-3, capable of speeds up to 1,400mph (2,300km/h), Brennan convinces Willis that a record-breaking flight from Nome, Alaska to Washington D.C., via the North Pole, will impress the government. At the same time, Troxell tries to develop a safer version of the revolutionary aircraft, the JA-4, equipped with an escape pod, but dies during a test flight. The earlier record flight is a success with Brennan earning a $30,000 paycheck, enough to marry Jo. Then he learns that Troxell has been killed. Despite his earlier reservations about the need for safety systems, Brennan takes another JA-4 out for the official government demonstrations, using the escape pod to prove that the new aircraft is safe. On landing, he falls into the arms of his beloved.
Answer:
Who designed the jet-fighter, JA-3?