Note 34 — Chapter IX · HISTORY OF LAUNCHING APPARATUS AND FIELD-TRIALS OF AERODROMES 4, 5 AND 6
Reading edition
It may be observed that at this time the position of the CP was calculated on the assumption that the pressure for flight surfaces was proportional to the areas, without also allowing for the fact that the following surfaces, like the tail, were under the “lee” of the wind and so far less efficient. It follows, then, that the value CP−CG was not really 0, as was assumed, but something considerable.