The invention relates to an elevation estimation method and a radar apparatus of the stacked beam type using it. For the accurate determination of the elevation of a object, use is made of interpolation on the basis of object strengths, measured in the different beams. Thus, an object of this invention is a method for estimating an object's elevation comprising: Receptions and associated receiving processing of signal reflected by the object; A beam transformation of said processed received signals into a number of receiving antenna beams which are at least substantially identical in azimuth direction and distributed in elevation direction; An interpolation of the receiving antenna beams, which are provided with a mutual overlap, such as the object's elevation is deduced by standardisation of set of strengths measured along the elevation direction distribution and comparison to pre-defined sets of strengths which have been associated with elevations, the comparison determining a best fitting set. In order to make interpolation also possible for low-flying objects, at least one beam having a negative elevation is provided.