§ 119. Sir J. Mellor
asked the Parliamentary Secretary to the Ministry of Civil Aviation to state the results of his further investigations into the blocks of ice which have fallen recently.
§ Mr. Beswick
Of the six cases reported, in one it is probable that the ice formed around an aircraft's waste water outlet, and became detached on descent into warmer air. This possibility is being examined with the operators thought to have been concerned. To obviate trouble of this nature in British aircraft the Air Registration Board is, at the request of my Ministry, requiring from 1st January, 1951, that waste water systems discharging overboard shall be designed so that water from them cannot freeze on the aircraft. In another case it is probable that the ice fell from a particular aircraft but from which part of it has not yet been established. In the other four cases there is no direct evidence that aircraft were involved. It is not considered that meteorological phenomena were responsible and investigations continue.