Final answer:
The correct speed to slow down a Piper Seminole during moderate turbulence is not provided in the options. The aircraft's operating handbook or manufacturer's guidelines would specify the 'turbulence penetration speed'. This reduced speed minimizes the risk of structural damage during turbulent conditions.
Step-by-step explanation:
If you were operating a Piper Seminole that weighed 3800 lbs and encountered moderate turbulence, the speed you should slow the aircraft down to in order to avoid structural damage is not specifically listed among the options provided (any speed below 169 KIAS, 135 KIAS, 129 KIAS, or 112 KIAS). To answer this question correctly, you would need to refer to the aircraft's specific operating handbook or manufacturer's guidelines under the 'maximum operating maneuvering speed' (Va) or 'turbulence penetration speed', which varies by aircraft make and model.
For the Piper Seminole and similar light aircraft, the manufacturer or the operating handbook often prescribes a reduced speed—often referred to as 'turbulence penetration speed'—to be used when flying in turbulence to prevent overstressing the airframe. This speed is well below the maximum structural cruising speed (Vno) and is designed to minimize the risk of structural damage during turbulent conditions.
The concept here is related to aviation safety and the principle of flying at an appropriate speed that allows the aircraft to cope with unexpected gust loads without causing damage. Pilots are trained to recognize and respond to such conditions by adjusting airspeed accordingly.