Aircraft spotting or Plane spotting is the enjoyment, observation and photography of aircraft: gliders, powered aircraft, large balloons, airships, helicopters, and microlights.

When spotting planes, observers notice the key attributes of an aircraft. They may notice a distinctive noise from its engine(s) or the number of vapour trails it is leaving against a blue sky. They will assess the size of the plane and the number, type and position of its engines. Another clue is the position of wings relative to the fuselage and the degree to which they are swept rearwards. Are the wings above the fuselage, below it, or fixed at midpoint? Perhaps it is a biplane or triplane. The position of the tailplane relative to the fin(s) and the shape of the fin are also clues to its type. If it is an antique or light aircraft it might have a tail wheel. Some aircraft types have a fixed undercarriage whilst others have retractable wheels.

Other features may come into view, the speed, cockpit placement, colour scheme or special equipment that changes the silhouette of the plane. Taken together these clues will rapidly hasten the correct identification of a plane. If the observer is familiar with the airfield being used by the aircraft and its normal traffic patterns, he or she is more likely to leap quickly to a decision about the aircraft's identity - they may have seen the same type of aircraft from the same angle many times.

Some spotters will note the markings, a national insignia or airline livery or logo perhaps, a squadron badge or code letters in the case of a military craft. Published manuals allow more information to be deduced, such as the delivery date or the manufacturer's construction number. Camouflage markings differ, depending on the surroundings in which that aircraft is expected to operate.