Use instrumentation to pilot aircraft when visibility is poor. Start engines, operate controls, and pilot airplanes to transport passengers, mail, or freight according to flight plans, regulations, and procedures. Monitor engine operation, fuel consumption, and functioning of aircraft systems during flights. Check aircraft prior to flights to ensure that the engines, controls, instruments, and other systems are functioning properly. Consider airport altitudes, outside temperatures, plane weights, and wind speeds and directions to calculate the speed needed to become airborne. Contact control towers for takeoff clearances, arrival instructions, and other information, using radio equipment. Obtain and review data such as load weights, fuel supplies, weather conditions, and flight schedules to determine flight plans and identify needed changes. File instrument flight plans with air traffic control so that flights can be coordinated with other air traffic. Check baggage or cargo to ensure that it has been loaded correctly. Order changes in fuel supplies, loads, routes, or schedules to ensure safety of flights. Plan flights according to government and company regulations, using aeronautical charts and navigation instruments. Choose routes, altitudes, and speeds that will provide the fastest, safest, and smoothest flights. Co-pilot aircraft or perform captain's duties as required. Coordinate flight activities with ground crews and air traffic control, and inform crew members of flight and test procedures. Request changes in altitudes or routes as circumstances dictate. Write specified information in flight records, such as flight times, altitudes flown, and fuel consumption. Supervise other crew members. Fly with other pilots or pilot-license applicants to evaluate their proficiency.