direction of movement has an approximately crescent shaped configuration and is also concave the detachable mounting of the grass clearing plate 22 is carried out by means of brackets 23 having opposite ends bent in opposite directions each of the brackets 23 is secured by means of wing nuts 24 in which the lower bent ends are secured to the substantially vertical housing portion 25 referring now to fig7 which is somewhat similar to the embodiment disclosed in fig6 a further grass clearing plate 33 is shown detachably mounted on the rear side of the air cushion lawnmower by means of a bracket 23 not shown in addition however the first grass clearing plate 22 is mounted by means of bracket 23 having more wing nuts 24 than that shown on fig6 it should be evident that the detachable mountings of the grass clearing plates on the lawnmower housing 1 as illustrated in fig6 and 7 may be substituted for other types of attachment means which will achieve the desired function thus the grass clearing plates may be mounted by means of a multipart height adjustment rack arrangement or a rapid coupling such as a bayonet fastening arrangement it is desired to point out that the use of grass clearing plates on conventional air cushion lawnmowers results in a more desirable structure referring now to fig8 and 9 in which a lawn surface is mowed with an air cushion hovering type lawnmower 62 the lawnmower mows the grass area in a concentric rectangular pattern from outside inwardly on successive right angle turns so that the cut grass is ejected into the section 61 of the lawn surface which is uncut and rectangular grass swaths are.