-----------+---------+----------- | Primary | Advanced | training| training | planes, | planes, | SJ-1, | JN-4 and | JN-4D, | 6H, S-4B | Penguin.|and C, E-1, | | SE-5. -----------+---------+----------- 1917 | | April | | May | | June | 9 | July | 56 | August | 103 | September | 193 | October | 340 | November | 331 | 1 December | 423 | 20 | | 1918 | | January | 700 | 29 February | 526 | 199 March | 756 | 178 April | 645 | 81 May | 419 | 166 June | 126 | 313 July | 236 | 427 August | 296 | 193 September | 233 | 132 October | 212 | 320 November | 186 | 297 December | 162 | 259 |---------+----------- Total | 5,952 | 2,615 -----------+---------+----------- THE SERVICE PLANES. It was not until we took up the production of fighting, or service, airplanes that we came into a full realization of the magnitude of the engineering and manufacturing problems involved. We had perhaps a dozen men in the United States who knew something about the designing of flying machines, but not one in touch with the development of the art in Europe or who was competent to design a complete fighting airplane. We had the necessary talent to produce designs and conduct the manufacture of training planes; but at the outset, at least, we were unwilling to attempt designs for service planes on our own initiative. At the beginning we were entirely guided by the Bolling mission in France as to types of fighting machines. In approaching this, the more difficult phase of the airplane problem, our first act was to take an inventory of the engineering plants in the United States available for our purposes. With the Curtiss Co. was Glenn Curtiss, a leader of airplane design, and several competent engineers. The Curtiss Co. had been the largest producers in the United States of training machines for the British and had had the benefit of assistance from British engineers, and so possessed more knowledge and experience to apply to the service-plane problem than any other company. For this reason we selected this plant to duplicate the French Spad plane, the story of which undertaking will be told further on.