The discussion centers on the existence and feasibility of four spool engines, with participants noting that such designs are rare and potentially problematic due to increased complexity and weight. Concerns are raised about maintenance challenges associated with four spool engines, suggesting that the focus should remain on two and three spool designs. The triple spool engine is highlighted for its efficiency and capability to minimize engine surges, making it a preferred choice in aviation. Overall, the consensus leans towards the practicality of existing spool designs rather than exploring the complexities of a four spool engine. The conversation emphasizes the importance of efficiency and reliability in engine design.
