In 1931, Robert Goddard patented a rocket-fueled aircraft design (U.S. No. 1,809,271). However, it drew no military interest from either the Army or the Navy, despite its innovative design, since even the government following the great Depression had limited resources to fund proper research. The invention was designed to utilize the energy of the gas blast of a rocket without dissipation to obtain the maximum propulsive effect by driving one or more turbine elements, which in turn could turn propellers for driving the plane in the usual manner at low altitudes. The invention also proposes using the reaction of the gas blast itself at such higher altitudes where the air is so thin that propellers would be useless.[Image: patent diagram showing propellers at the rear.]