A review of the analytical methods used for seaplanes’ performance prediction <s> Introduction: <s> This survey has the objective of reviewing research and development of wing-in-ground effect technology. Starting with definitions of the phenomenon and the craft which takes advantage of the ground effect (GE), the history and perspectives of the technology, specific vehicles and projects, and areas of application are covered. Special attention is paid to GE aerodynamics, its mathematical modeling and the stability of longitudinal motion. Also briefly discussed are issues of motion control, structural design, materials and economics. Covered in more detail are matters related to rules of classification, safety and certification. Conclusions are followed by a bibliography, including about 769 entries. <s> BIB001 </s> A review of the analytical methods used for seaplanes’ performance prediction <s> Introduction: <s> This research is based on the investigation into the dynamic stability associated with seaplanes during takeoff. Various forces acting on a hydroplaning hull form have been empirically defined. Such empirical data have shown that, under a certain set of conditions, a hydroplaning hull will begin to porpoise: an instability oscillation in both the vertical direction and about the center of gravity. To investigate the porpoising motion, a shallow water flume was used. It was the first time that such a facility had been used to simulate the dynamic motion of hydroplaning hull forms. An experimental method derived from the store release experiments was derived for the dynamics measurements. The equipment developed led to an analysis of a flat-plate hull porpoising in a supercritical channel. The porpoising limit was then very well defined. <s> BIB002
Aviation business expects a major increase in global air traffic, while the aviation industry is under pressure to deteriorate noise and emissions. In fact, the rising concerns about noise and air pollution in the areas close to large airports are affecting the capacity and expansion of the airports. One of the potential solutions for this issue is to build airports away from populated areas in offshore locations which means moving take-off and landing paths over water. However, the cost of land reclamation and the need for new terminal buildings and pathways to be constructed is very expensive. A substantial alternative that would abolish the need for such expensive infrastructure expenditure would be the use of waterborne aircraft. Since the beginning of the nineteenth century, the concept of waterborne ground effect aircraft (also known as Wing-In-Ground "WIG" Craft, Ekranoplan, Seaplane or Ground Effect Vehicle "GEV") has been widely investigated due to its ability to cover a wide range of applications as well as its ability to combine between the characteristics of aircrafts and marine crafts. Moreover, as almost 71% of the earth's surface is water, the waterborne aircraft could provide access to almost every part of the world. According to BIB001 , the WIG craft is a heavy vehicle with an engine that is designed to fly close ground or water surfaces for efficient utilization of the Ground Effect. The latter also defined the Ground Effect "GE" as an increase of the lift-to-drag ratio of a lifting surface at small distances from ground or water surfaces BIB001 . Seaplanes have similar performance characteristics as planing hulls as they are both designed to glide on top of water surfaces and take advantage of the positive dynamic lift produced by their motion. This was supported by  who claims that high speed vessels including all monohulls, catamarans and trimarans having speeds greater than 16 m/s  . Therefore, the appropriate hydrodynamic stability prediction is the key to a successful seaplane design. Planing hulls have a unique instability phenomenon called porpoising which, according to Faltinsen (2005) , can be defined as a periodic, bounded vertical motion that a craft might show at certain speeds  . This phenomenon can be seen as an oscillatory motion in the heave and pitch axes and can cause severe damage to the structure of the craft. In some cases, if the hull is leaving water and returning at negative trim angle, the craft will submarine. It is therefore very important to predict the behaviour of the seaplane in the design stage BIB002 . The purpose of this paper is to advance the understanding of the analytical methods used to predict the performance of seaplanes. In addition, the paper will identify the weaknesses in the current methods and discuss how the analytical approach can be extended. The first section of the paper will illustrate the seaplane motion characteristics. In the second section, the analytical methods available in the literature will be briefly discussed in which the advantages and disadvantages of each of them will be stated. After that, the heave and pitch equations of seaplane motion will be presented along with a proposed solution. Lastly, the results obtained from different analytical methods will be compared and conclusion drawn.