A multitude of aircraft types were tested in combat in the war period 1914-18, and literally hundreds of prototypes of diferent designs were built and flown. These numbers become believable when one considers that the prototype of a fighter aircraft could be designed, constructed, and test flown within a period of a few weeks. Most did not enter production, and most designs that did enter "production" were only produced in small numbers. The rapid progress of performance rendered most designs obsolete within a year or two, and only a few designs were producted in large numbers or served for much of the duration of the war.
A guide the military aircraft of this era must avoid the Scylla of an excessive parsimony in selection focused on a few stars, and the Charybdis promiscuous inclusiveness that overwhelms with trivial detail.
. . . I had been content to perish, falling on the foreman's ground,
When the ranks are roll'd in vapour, and the winds are laid with sound.
But the jingling of the guinea helps the hurt that Honor feels,
And the nations do but murmur, snarling at each other's heels.
For I dipt into the future, far as human eye could see,
Saw the Vision of the world, and all the wonder that would be;
Saw the heavens fill with commerce, argosies of magic sails,
Pilots of the purple twilight, dropping down with costly bales;
Heard the heavens fill with shouting, and there rain'd a ghastly dew
From the nations' airy navies grappling in the central blue;
Far along the world-wide whisper of the south-wind rushing warm,
With the standards of the peoples plunging thro' the thunder-storm;
Till the war-drum throbb'd no longer, and the battleflags were furl'd
In the Parliament of man, the Federation of the World.
"Locksley Hall" Alfred Lord Tennyson 1842
"Secretly the Central European Power had gathered his flying machines together, and now he threw them as a giant might fling a handful of ten thousand knives over the low country. ... From north and west and south the allied aeroplanes rose in response and swept down upon this sudden attack. So it was that war in the air began. Men rode upon the whirlwind that night and slew and fell like archangels. The sky rained heroes upon the astonished earth."
The World Set Free: A Story of Mankind
By Herbert George Wells 1913