[Ginger.]

Bad move excluding 'Bloody April' by Peter Hart, it doesn't cover the entire war but definately tells you 'who did what to who'!
This review of the book gets it spot on in my 'umble opinion...

"Bloody April is about the air war over Arras in 1917: the
British lost large numbers of aircraft to the Germans, and
the life expectancy of a rookie pilot could be measured in
days. Yet, paradoxically, the British won the battle that
month. Bloody April goes into depth on the characteristics
of the aircraft, the training, the prelude to April and the
aftermath: there are innumerable quotes from diaries,
letters home, and other accounts that help show the attitudes
and the stress.

The romantic view of the war in the air in W.W. I is usually
that of single-seat fighters in combat with each other. The
reality is that for the RFC in the Arras sector, only a third
of the aircraft were single-seaters: the rest were all two-
seaters, although some of these had to be employed as fighters
at times. The primary mission of the RFC was to help with
photo reconnaissance (thousands of photographs had to be taken
each day) and artillery spotting (using wireless transmitters
to help artillery zero in on targets). The primary role of the
fighters was to escort the photo recon and artillery spotting
aircraft and to screen them by offensive patrols. Trench-
strafing, anti-balloon attacks, and bombing were of secondary
importance, as was the need to prevent photo recon and artillery
spotting by the Germans.

The German fighters were far superior to almost all of the
British two-seaters, and were superior to most of the British
fighters, but the Germans had only half as many aircraft in
the sector as the British, and so they usually played a
defensive role. The British accepted very heavy losses in
exchange for getting the photographs and the artillery
spotting done. There are quotes about how a squadron with
32 planes lost 35 pilots during April--replacement pilots
would survive only a few days. Flying a BE2 with only 10 hours'
flying experience against veteran German pilots whose planes
were twice as fast and had twice the firepower was not
conducive to lasting very long.

Bloody April never gets bogged down in small details--it gives
a first-class flavor to what things were really like, and it
helps dispell the romantic myths. It's a fine book.!"

Good Hunting.