 In 1968, Caribair was operating a mixed fleet consisting of both McDonnell Douglas DC-9-30 jets and Convair 640 turboprops with the latter being used to provide scheduled flights into destinations that were either operationally constrained with regard to DC-9 service or simply could not support the passenger numbers required for profitable jet operations.A number of these destinations were eliminated from the Caribair route system when the airline decided to operate only DC-9 jet service.These former destinations included the islands of Dominica, Grenada, St. Vincent and St. Kitts as well as Mayaguez, Dorado and Ponce on the island of Puerto Rico.