GUIDES TO FLYERS

Dominion, Volume 29, Issue 254, 23 July 1936, Page 13

GUIDES TO FLYERS

Landing Facilities at Rbngotai SMOKE SIGNAL STOVE A landing circle, complete with smoke signal, is being constructed at Kongotai Aerodrome by the Wellington City Council for the assistance of pilots when landing machines. The circle is one ..f 50 feet and is placed as near as possible to the central point of the aerodrome. It is made of a mixture of spent carbide and sand let into a shallow trench, filling it to ground level. When dry the mixture is almost white, so that from the air it will stand out clearly. The white circle is the standard aerodrome marking in many other countries, indicating to a visiting pilot the presence of the ground as well as its centre.

Inside the circle and sunk into the ground is a stove burning oil, the chim-ney-top being level with the aerodrome surface. When lighted the stove gives off a continuous stream of black smoke which, Issuing from the chimney, shows the direction of the wind even more efficiently than the standard windsock, A smoke signal, besides indicating the direction of the wind, gives an observant pilot approximate guides to its strength. In a strong wind, for instance, the wisp of smoke is blown practically along the ground, whereas an almost directly ascending pillar of smoke indicates a very light wind. With both the circle and the stove sunk to the ground level there is no interference with the landing-space on the aerodrome, as a machine can taxi right over the situation of the installation without damage to itself, the circle or the stove.

The making of the landing circle and smoke signal coincides with common practice in aerodrome equipment overseas. On some aerodromes the smoke signal is made by having a lamp constantly heating a metal plate embedded in the centre of the circle, with oil slowly dripping on to a hot plate, giving continuous smoke. At Rongotai the oilburning stove has been adopted as easier to construct and install.

The smoke signal will probably not be used continuously, but will be taken advantage of mainly at week-ends, when there is considerable flying activity at the aerodrome. Two wind Indicators of unusual type have also been installed on the seaward boundary of the aerodrome to supplement the windsock by the hangar. These are of the pointer type, worked on the same principle as the weather-vane, being made of x light timber, pivoted in the centre and kept pointing into the wind by a tail fin. The whole structure, being only about two feet above the ground, offers no obstruction to landing. It is painted chrome and is about eight feet long, so that it can be seen quite readily from above.