Every noon, whilst at sea, the foghorns and whistles are tested prior to the navigation information being given over the PA system. In this clip, the foghorns sound first, followed by each of the two Tyfon® whistles (one of which is on permanent loan from the original Queen Mary, having been removed from its concealed position on the middle funnel) situated either side of the funnel. Each whistle is about 7 ft (~ 2.1 m) long and 3 ft (~ 1 m) high, with the sound produced via a 22 in. (57 cm) diaphragm, and weighs about two-thirds of a tonne. The original whistle sounds at a frequency of 55 Hz but the modern replica sounds at a present regulation minimum (for this size of ship) of 70 Hz. Both now operate by means of compressed air rather than steam.
26 авг 2010
