A unique configuration, known as an Underpowered Aircraft, allows for the modification of gliding flight vehicles for increased range and lower cost when compared with fully powered flight vehicles. Intentionally under-sizing the powerplant for a flight vehicle allows the designer to choose a powerplant that will not only perform the mission requirements, but will also provide the customer with the most cost effective solution, as some missions may not require fully powered flight. Specifically, the underpowered aircraft concept studied in this paper is a gliding flight aircraft that does not have enough power for climbing or level flight, but does have enough power to overcome some of the drag forces associated with flight, in turn increasing the effective range of the vehicle. In this paper, the underpowered aircraft concept was analyzed and its feasibility was determined. Analysis done using equations of motion, followed by a more accurate numerical integration including a thrust lapse, determined that the underpowered aircraft concept provides a unique method for a cost effective range extension technology for gliding flight vehicles. Finally, the technology and methods of this paper were applied to the AGM-154 JSOW and JSOW-ER glide munitions and it was determined that JSOW-ER is representative of an underpowered aircraft with our analysis. This paper represents a "back-of-the-envelope" investigation into the underpowered aircraft concept.
Available at: http://works.bepress.com/ramcdona/19/