The airplane seen at the end of the film is a 1929 Lockheed Vega, registration NC48M. It was owned by Paul Mantz, a famous stunt pilot and aviation entrepreneur. He was a friend of Howard Hughes and a technical advisor to Amelia Earhart. He owned United Air Services that provided aircraft and pilots for many films, in addition to having an air ambulance service. This particular aircraft was named the "Honeymoon Express" as it flew newlywed couples to Las Vegas and Reno, Nevada and Yuma, Arizona - honeymoon hot-spots at the time. This aircraft was being used for the film "Only Angels Have Wings" (1939) when it crashed upon landing at St. George, Utah and was damaged beyond repair.
According to the Hollywood Reporter's April 22, 1935 issue the Acme Window Cleaning Co. sued Warner Brothers for the use of the names Acme Window Cleaning Co. and Peerless Window Cleaning Co. Because the Acme company in the film was portrayed as unscrupulous, the real Acme Co. asked $100,000 in damages. The outcome of the suit has not been determined.
The working title of the film was "Gentlemen Are Born" - a title that was used on another Warner Brothers picture in 1934.
The open-cockpit monoplane seen at the end of the film is a 1933 Kinner Sportster K, registration NC13700. As of 2017 that aircraft is still registered in Washington state.