Please answer the following question: Information: - A flying ace or fighter ace is a military aviator credited with shooting down several enemy aircraft during aerial combat. The actual number of aerial victories required to officially qualify as an "ace" has varied, but is usually considered to be five or more. The few aces among combat aviators have historically accounted for the majority of air-to-air victories in military history. - Flight Lieutenant (Flt Lt in the RAF and IAF; FLTLT in the RAAF and RNZAFformerly sometimes F/L in all services) is a junior commissioned air force rank that originated in the Royal Naval Air Service and is still used in the Royal Air Force and many other countries, especially in the Commonwealth. It is also sometimes used as the English translation of an equivalent rank in non-English-speaking countries, especially those with an air force-specific rank structure. - The Battle of Britain (German: "die Luftschlacht um England", literally "Air battle for England") was a combat of the Second World War, when the Royal Air Force (RAF) defended the United Kingdom (UK) against the German Air Force (Luftwaffe) attacks from the end of June 1940. It is described as the first major campaign fought entirely by air forces. The British officially recognise its duration as from 10 July until 31 October 1940 that overlaps with the period of large-scale night attacks known as the Blitz, while German historians do not accept this subdivision and regard it as a campaign lasting from July 1940 to June 1941. - An aircraft is a machine that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. - Flight Lieutenant Carl Raymond Davis DFC ( 30 July 1911 -- 6 September 1940 ) was a flying ace of the Battle of Britain , having claimed nine enemy aircraft ( and one shared ) destroyed , four ( and one shared ) probably destroyed , and four damaged , before he was himself shot down and killed in action . Davis was one of 11 American pilots who flew with RAF Fighter Command between 10 July and 31 October 1940 , thereby qualifying for the Battle of Britain clasp to the 1939 -- 45 campaign star . - The Royal Air Force (RAF) is the United Kingdom's aerial warfare force. Formed towards the end of the First World War on 1 April 1918, it is the oldest independent air force in the world. Following victory over the Central Powers in 1918 the RAF emerged as, at the time, the largest air force in the world. Since its formation, the RAF has taken a significant role in British military history, in particular, playing a large part in the Second World War where it fought its most famous campaign, the Battle of Britain. - The Luftwaffe was the aerial warfare branch of the combined German Wehrmacht military forces during World War II. Germany's military air arms during the First World War, the "Luftstreitkrafte" of the Army and the "Marine-Fliegerabteilung" of the Navy, had been disbanded in May 1920 as a result of the terms of the Treaty of Versailles which stated that Germany was forbidden to have any air force. - The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British Army's Royal Flying Corps to form a new service, the Royal Air Force, the first of its kind in the world. What is the relationship between 'carl raymond davis' and 'royal air force'?
A:
military branch