Published online by Cambridge University Press: 04 July 2016
This paper reviews the requirements of the AHS human-powered helicopter (HPH) competition and discusses the feasibility of such a helicopter. Analysis is carried out with modified forms of the axial momentum theory to take into account the ground effect. Descent in autorotation is also considered. The main conclusions are: human-powered hover out of ground effect is not possible; the power loading decreases with the number of pedaling crew members; hover in ground effect significantly increases the rotor thrust at given power; the HPH operates in the vortex ring state; in principle, either altitude or endurance records can be reached for the AHS contest, but not both, due to insufficient power.