Abstract: Aluminium alloy and a method of making it, whereby the alloy contains Zr and from 0 to 1% of one or more of the elements Mg, Si, Ag, Ni and Cu, the balance being mainly Al, the alloy being made on the basis of a melt which contains 0.5 to 2% by weight of Zr and which has been cast into particles by being cooled with such a high velocity that the Zr mainly is present in a supersaturated solution. The particles are consolidated and the Zr is precipitated as finely distributed dispersoids after a heat treatment at 300.degree. to 450.degree. C., and the alloy has an electrical conductivity of at least 58% IACS and a 10% softening temperature of at least 400.degree. C. The consolidation may for instance be carried out by extrusion.

Abstract: Landing deck for aircraft, in particular for helicopters, on seagoing vessels and offshore installations, such as platforms. When fuel is leaking from a helicopter after an accident, as for instance an unsuccessful landing, a fire often starts. In order to reduce the combustion intensity and the duration of such a fire continuous grooves or channels (8) are formed in beams of steel or metal, of which the deck is made, in the surface facing upwardly. Thereby fuel which has leaked out will be collected in the grooves or channels. The air supply to the grooves or channels is poorer than the air supply to fuel situated on decks without grooves or channels, and the combustion intensity, therefore, is reduced. Moreover, the combustion takes place on the surface of the liquid, and it is possible to drain a substantial part of the fuel without ignition thereof. Fuel may be collected from the grooves or channels by means of a collecting manifold or gutter.