THE AIRCRAFT TREE

An unrecorded Australian aviation educational chart from the dawn of the jet age, produced by the Department of Visuals Aids, University of Melbourne, for the Education and Information Branch Department of Civil Aviation.

The poster depicts a great gnarled tree whose trunk, labelled “Aircraft”, divides into two limbs:

1. “Lighter than Air” (barrage balloons, balloons and airships, with cutaway diagrams of rigid dirigibles and non-rigid blimps.
2. “Heavier than Air” (aeroplanes — land planes, seaplanes, flying-boats, float planes and amphibians; motorless flight — gliders, sailplanes and box kites; autogiros, helicopters and rockets), with one branch left deliberately bare “for recording the possible development of a machine that will move through the air by flapping its wings… known as an ornithopter”.

Individual aircraft identified include;

• Sikorsky S-51 helicopter (drawn with British registration G-AJOO)
• Douglas DC-6 airliner
• Percival Proctor VI four-seat cabin seaplane
• Short Sealand amphibian
• Eight-engined Hughes flying-boat

A didactic caption observes that the lighter-than-air side of the tree “has apparently stopped development” — a statement of post-war aeronautical orthodoxy, printed barely a decade after the Hindenburg. Produced for classroom distribution by the University of Melbourne’s Visual Aids Department for the Commonwealth Department of Civil Aviation, then headquartered in Melbourne.

The dating of this poster has been ascertained from the following evidence;

1. The Short Sealand amphibian (first flown January 1948) provides a firm terminus post quem
2. The Hughes flying-boat (flown November 1947) cited as a current example
3. The Sikorsky S-51 bearing British registration G-AJOO (allocated 1947)
4. The Douglas DC-6 as exemplar airliner
5. Jet propulsion presented as an unnamed emergent principle

Not in Trove.