The first jet plane flew in secret, and officials were unimpressed
On 27 August 1939 the Heinkel He 178 became the first aircraft ever to fly on turbojet thrust. Its maiden flight lasted six minutes and nearly ended badly on landing. When senior officials finally watched a demonstration that November, they shrugged: it was slow for a jet and could stay aloft only about ten minutes.
The engine came from Hans von Ohain, a young engineer who in 1935 patented the idea of propelling an aircraft with a gas turbine's exhaust. He took it to aircraft maker Ernst Heinkel, who was already curious about gas turbines and agreed to back him. Von Ohain's first engine ran in September 1937, and the He 178 was designed around his third, which could burn diesel or petrol. Before that, the engine was test flown as a helper strapped onto a conventional piston-engined Heinkel He 118.
Heinkel paid for everything himself and kept the project hidden, even from the Luftwaffe. The aircraft was compact, with a mostly metal fuselage, an air intake in the nose, the engine buried inside, and high wooden wings with an elliptical trailing edge. Its landing gear was meant to retract but stayed down throughout the trials. Test pilot Erich Warsitz later recalled feeling disappointed as the plane rolled off slowly, before it gathered speed and lifted away with the turbine howling.
Performance was the problem. Even with a more powerful engine it topped out at 598 kilometres per hour, and officials including Ernst Udet and Erhard Milch saw little to excite them. Heinkel blamed the air ministry's failure to grasp what jets could do. Unknown to him, the ministry was already funding its own jet work, and the engines Junkers and BMW went on to build used an axial-flow layout rather than von Ohain's centrifugal design.
Undeterred, Heinkel launched the twin-engined He 280, the first prototype jet fighter, as another private venture. It drew on lessons from the He 178 rather than copying it, dropping impractical features such as the engine mounted inside the fuselage. The original prototype went on display in Berlin, only to be destroyed in an Allied air raid in 1943.
Source: Heinkel He 178
