A safety arrangement for an aircraft, especially for amphibious aircraft, being configured for determining a type of landing surface (such as water/solid ground) and including: two transceivers (301, 302); the first transceiver (301) configured to operate on first electromagnetic wavelength and the second transceiver (302) configured to operate on second electromagnetic wavelength differing from the first wavelength, and at least one of transceivers is configured to receive the reflections electromagnetic wavelengths, and determining element for determining the type of the landing surface based on the properties of two electromagnetic wavelengths reflected from the landing surface and for outputting a signal indicating the type of the determined landing surface.