Memorandum presenting a summary of the methods for estimation of water landing loads on hydro-ski-equipped aircraft in order to provide a unified picture and bibliography of NACA work on the subject. Two approaches to the problem of calculating hydro-ski landing loads are covered. Results regarding the impact load theory for rigidly mounted hydro-skis, effect of chine immersion on landing loads, impact load theory for shock-mounted hydro-skis, and estimation of the water pressure distribution on impacting hydro-skis are provided.