Supercooled large droplet （SLD） icing is beyond of the protection ability of the conventional anti-icing system. SLD is a more serious icing environment and could badly affect the flight safety. In order to ensure flight safety in the SLD icing condition， the precondition is that the SLD should be detected explicitly required by the 14 CFR 25.140 of Federal Aeronautics Administration. It is found that the breakup of droplets will change their trajectory and distribution， and reduce the impingement limit on the wing-leading edge， while the splash of droplets has little effect on the impingement limit. Therefore， ice detection technologies satisfying airworthiness compliance of SLD is studied in this paper considering the characteristics of a various range of large and small droplets. Conventional ice detectors with mature technologies are used and are located in the ice sensitive zones according to the collection range of water droplets. It can detect the whole ice environment in the methods above.