Why can engines only operate for 30 minutes with less than 1000 lb of fuel per side?

The correct response highlights a critical aspect of operational limits in engine performance regarding the cooling of hydraulic systems. Engines require a sufficient amount of fuel not just for combustion, but also for maintaining the proper temperature of hydraulic fluids. When fuel levels drop below a certain threshold, such as less than 1000 lb per side, the risk of overheating increases because there may be inadequate fuel to assist in cooling.

Lower fuel levels can lead to inefficient thermal management in the engine's hydraulic systems. If the hydraulic fluid overheats, it can negatively affect the performance and longevity of engine components, possibly resulting in failure or operational inefficiencies. Thus, the operational limit of 30 minutes with less than 1000 lb of fuel is primarily to prevent overheating and ensure the reliability of hydraulic functions, which are crucial for safe engine operation.

While fuel starvation, fuel contamination, and engine wear are valid concerns in the context of engine operation, the specific limitation placed by fuel quantity in this scenario is more closely related to the management of temperature and hydraulic fluid integrity.