4-3 certificate, a pilot’s operating handbook (POH), and/or  limitations with a weight and loading document aboard.  a Repairman: Light Sport certificate, and (in some cases) by  their pilots and/or owners. As mentioned earlier, WSC aircraft are commonly called  trikes. These aircraft have few options for loading because  they lack places to put useful load items. One-place trikes  have only one seat and a fuel tank, which means the only  variables for a flight are amount of fuel and weight of the  pilot. Two-place trikes can accommodate a pilot and a  passenger. This version may have a small storage bin in  addition to the fuel tank. The most significant factor affecting the weight and balance  of a trike is the weight of the pilot and, if the aircraft has two  seats, the weight of the passenger. The trike acts somewhat  like a single, main-rotor helicopter because the weight of the  aircraft hangs like a pendulum under the wing.  Figure 4-2 shows a two-place trike, in which the mast and the nose strut  come together slightly below the wing attach point. When  the trike is in flight, the weight of the aircraft hangs from  the wing attach point. The weight of the engine and fuel is  behind this point, the passenger is almost directly below this  point, and the pilot is forward of this point. The balance of  the aircraft is determined by how all these weights compare.  The wing attach point, with respect to the wing keel, is an  adjustable location. The attach point is moved slightly forward  or slightly aft, depending on the weight of the occupants. For  WSC aircraft are one- and two-place aircraft that exceed the  criteria of an ultra-light vehicle but do meet the criteria of an  LSA. The definition for WSC can be found in 14 CFR part 1.  A WSC aircraft used for sport and private pilot flying must  be registered with an FAA N-number, have an airworthiness  Figure 4-2.  CG of a trike. Aircraft such as balloons, powered parachutes, and WSC do  not require weight and balance computations because the load  is suspended below the lifting mechanism. The CG range in  these types of aircraft is such that it is difficult to exceed CG  limits. For example, the rear seat position and fuel of a WSC  aircraft are as close as possible to the hang point with the  aircraft in a suspended attitude. Thus, load variations have  little effect on the CG. This also holds true for lighter-than- air aircraft, such as a balloon basket or gondola. While it is  difficult to exceed CG limits in these aircraft, pilots should  never overload an aircraft, as doing so may cause structural  damage and/or failures.  Weight and Balance WSC Aircraft Weight affects performance; therefore, pilots should calculate  weight and remain within the manufacturer’s established  limits at all times. CG Aircraft CG • CG is under wing hang point for level flight. • Center of lift is directly above CG, above the wing hang point for level flight. Thrust line is typically  designed to be at vertical  CG. Fuel tank