An unmanned aerial vehicle (UAV) is provided, that is cost effective to use and manufacture and that includes a low count of component parts, allowing mission planners to use the UAVs in a disposable manner. The UAV includes an airframe having a central body and wings extending from the central body, defining an interior cavity. The airframe includes an upper and a lower shell, each configured of a unitary piece of plastic. The upper and lower shells have walls among them that define a fuel tank and a payload bay in a stacked configuration. The airframe can further include a payload cover configured to enclose the payload bay and to contribute to the central body of the airframe. A launch assembly is also provided. In a first configuration, a launch assembly is provided, that includes a container for housing multiple UAVs and a deployment mechanism that initiates rapid ejection of the UAVs from the container. In a second configuration, a launch assembly is provided, that includes an elastic tether connecting a UAV to an accelerated mass for gentle acceleration to flight speed under a stable tow.