'C+' is not an official designation. Actual aircraft are designated F-15C, but this model represents those that are equipped with a pair of either the more powerful Pratt & Whitney F100-229 or General Electric F110-229 engines. The extra engine thrust compensates for the extra weight added since the 'A' model and brings back the original Eagle's quick acceleration. These engines are installed in all F-15C's produced since 1989. [See also F-15C]
