Formation flight could greatly assist the air transport industry in tackling the challenges of environmental impact, excessive reliance on fuel and overcapacity. Previous studies have shown drag reductions leading to significant fuel savings for aircraft in formation relative to their solo flight. Safety is guaranteed with the use of extended formation distances, and practical implementation issues could be solved in the near future. Since studies so far have focused on existing aircraft configurations and technology, a case study using a strut-braced wing airliner was carried out to ascertain its applicability to less conventional craft. The present results did not indicate such clear-cut benefits. If formation flight is to be successful and beneficial for the next generations of aircraft, it will be vital to consider its interaction with new technologies developed for highly efficient operation, in particular those aimed at reduction of aircraft drag such as laminar flow, and to do so early in the design of aerospace vehicles and wider systems.

In a vessel type low power research reactor having vertical fuel plates, while circulating pump is switched off, coolant (light water) would flow by natural convection. By using conservation equations, taking into account simplifying assumptions, coolant mass flow rate through the channel can be obtained. Due to the thermal stratification effect, coolant mass flow rate through the channel is shown to decrease. The present study shows that, assuming a linear thermal stratification, the variations of coolant mass flow rate versus stratification parameter behave in a non-linear manner. The aforementioned variations decrease down to 41%.