Complex sentence: In late March 1930 contemporary observers recorded that the DB-80's test flights were awaiting better weather and a month later that tests were underway, but the first flight did not take place until 27 June 1930.
Split into simpler sentences: In late March 1930 contemporary observers recorded that the DB-80's test flights were awaiting better weather and a month later that tests were underway. The first flight did not take place until 27 June 1930.