The spinning nose dive has confronted the aeroplane designer with two main problems. The first is to evolve an unspinnable aeroplane, and the second to provide controls of sufficient power to ensure an immediate recovery from any spin into which an aeroplane can be forced. At the present time there seems little prospect of achieving a general solution of the first class of problem, although interesting particular solutions have been evolved from time to time. It seems now to be generally accepted that the unspinnable aeroplane would be desirable for every purpose, but it is evident that it must be achieved without sacrifice of performance or manoeuvrability. Moreover, it must be remembered that an imperfect solution of the first class of problem, such as can sometimes be achieved by limiting the power of the control surfaces, may be worse than useless; for the pilot may be deprived of the power to regain normal flight quickly if his aeroplane falls into a spin in unusual circumstances. It is, in fact, very unfortunate that many devices which point the way to the evolution of the unspinnable aeroplane also add to the difficulty of recovery from a spin. It is not my purpose to consider the methods which have been devised to prevent the incipient spin, which occurs when a conventional aeroplane is stalled, but to confine my attention to the problems of ensuring recovery from established spins. For the views expressed I must, of course, accept personal responsibility.