@izzythepush,
Thanks for the reply. I should add that a newspaper article contained the following:
"The people of El Centro and Imperial valley are to be given a practical demonstration of present day aviation. Word has just been received that Lieut. T. O. Paine, R. M. A., is to visit the valley in a high powered Curtiss plane today."
From the above, it seems to me that "R. M. A." was some sort of classification.