Although an excellent gun platform and exceptionally tough and powerful--even under most demanding combat conditions--lacked maneuverability and dependability at low speeds and had to be landed "power on." Introduction of SPAD XIII May 17 reversed balance of air power once again in favor of Allies. Soon over 80 French and 11 Allied squadrons equipped with them. US received 893 SPAD XIIIs which were enormous improvements over predecessor, Nieuport 28; latter had a habit of shedding fabric from upper wing in a dive. (Eddie Rickenbacker, America's leading ace, flew both Nieuport and SPAD XIII.) Span 26 ft 3 3/4 in; length 20 ft 4 in; height 7 ft 6 1/2 in; weight 1245 lbs empty, 1807 lbs gross; max speed 134 mph.