Career
Matthaei joined Saxon Field Artillery Regiment Number. 46 as an officer candidate on 13 February 1913. His first wartime service was in France.
He was commissioned on 23 April 1915.
He shipped out with his regiment to the Eastern Front. After a transfer to Infantry Regiment Number.
79, Matthaei returned to France in September 1915. In early 1916, he began aviation training.
He was assigned to Kasta 9 on 12 October 1916.
He upgraded to fighter pilot at Valenciennes during the first two months of 1917. In late February, he was posted to Jasta 21. On 24 March 1917, he shot down an observation balloon for his first victory.
After an unconfirmed claim on 15 April, he shot down a second balloon on 30 April.
By 22 November 1917, he had a string of nine victories credited to Jasta 21, even though he had been posted to Jasta 5 in June and become its temporary commander in August. On 17 December, he was promoted to command of Jasta 46.
On 17 April, he spun in, crashed, and burned on his home airfield. He was pulled alive from the wreckage, but died later that night.
He had been awarded both classes of the, as well as the Brunswick State War Service Cross.
