Heinkel He 178

Heinkel

Industry	Aerospace
Founded	1922 in Germany
Founder	Ernst Heinkel
Headquarters	Germany
Products	Aircraft, including Heinkel He 178

The Heinkel He 178 represents a pioneering experimental aircraft developed by the German manufacturer Heinkel. It holds the distinction of being the first airplane worldwide to achieve flight powered solely by a turbojet engine.

Conceived to validate the jet propulsion principle formulated by German engineer Hans von Ohain in the mid-1930s, the He 178 was a product of collaborative innovation. Von Ohain secured industrial backing from Ernst Heinkel, enabling him to demonstrate a functional turbojet engine, the Heinkel HeS 1, in September 1937. Heinkel advanced the He 178 project as an independent venture, operating without direct involvement from German authorities or the Luftwaffe, and maintained a degree of secrecy throughout its development. The initiative aimed not only to showcase the potential of aviation gas turbine technology but also to explore advancements in high-speed aerodynamics.

The initial prototype, He 178 V1, conducted its inaugural flight on 27 August 1939 with pilot Erich Warsitz at the controls. This maiden sortie lasted approximately six minutes, following a brief hop performed three days earlier by the same aircraft. Despite its groundbreaking propulsion system, the He 178’s limited maximum velocity of 598 kilometres per hour (372 mph) and modest endurance failed to impress prominent Nazi officials such as Ernst Udet and Erhard Milch, who observed a demonstration flight. Building on insights gained from the He 178, Heinkel proceeded to develop a twin-engine jet fighter, culminating in the He 280. The He 178 contributed essential experimental data that informed subsequent jet aircraft designs. The prototype was later exhibited statically in Berlin but was ultimately destroyed during an Allied bombing raid in 1943.

Background

In 1935, young German engineer Hans von Ohain secured a patent for utilizing exhaust gases from a gas turbine as a propulsion method. Von Ohain presented this concept to aeronautical engineer Ernst Heinkel, who found it compelling enough to support its development. This industrial partnership proved crucial for advancing von Ohain’s work. According to New Scientist, Heinkel had already expressed interest in gas turbine technology prior to his collaboration with von Ohain.

By September 1937, von Ohain had successfully demonstrated his initial engine model, the Heinkel HeS 1. This milestone led to initiating design efforts for an aircraft capable of housing and testing such an engine in flight. The resulting aircraft, designated He 178, incorporated von Ohain’s third engine iteration, the HeS 3, which operated on either diesel fuel or gasoline. To facilitate development, the HeS 3 engine was trialed aboard a Heinkel He 118, albeit as an auxiliary power source alongside its conventional piston engine.

The He 178 was designed as a compact airframe featuring predominantly metal construction and adhering largely to conventional aerodynamic layouts. Its nose section contained the air intake feeding the centrally mounted engine within the fuselage. The aircraft employed a tailwheel undercarriage configuration; although its main landing gear was intended to retract, it remained fixed in the extended position throughout all flight tests. It featured high-mounted wooden wings characterized by the distinctive elliptical trailing edge wing planform developed by the Günter brothers. Photographs depicting a straight-tapered wing planform correspond to the second prototype, He 178 V2, which never achieved powered flight.

Into flight

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The He 178 V2, identifiable by its squared-off wing tips. This model was flown exclusively as an unpowered glider

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Design schematic of the He 178

On 27 August 1939, just days prior to Germany's invasion of Poland, the aircraft completed its maiden flight. Piloted by Erich Warsitz, this initial flight lasted approximately six minutes and nearly ended in catastrophe due to a miscalculated unpowered landing approach, though Warsitz managed to recover successfully. Reflecting on the historic flight, Warsitz recalled: "I eased the throttle forward. At first, I was somewhat disappointed by the thrust; unlike the 176, it did not surge ahead but accelerated gradually. By the time I reached 300 metres, the speed was considerable. Despite multiple attempts, I was unable to retract the landing gear. That was inconsequential; the key point was that it flew. The rudder and flaps functioned almost as expected, and the turbine emitted a loud roar. Now I faced the challenge of landing, reducing altitude through side-slipping. Just before touchdown, I corrected the attitude, executed an excellent landing, and pulled up just before reaching the Warnow."

The turbojet engine and its test platform, the Heinkel He 178 V1, were developed under strict secrecy by Heinkel. Even the Luftwaffe remained unaware of their existence. Following Germany's conquest of Poland, on 1 November 1939, Heinkel organized a demonstration of the aircraft for several Nazi dignitaries. Although Hermann Göring, commander-in-chief of the Luftwaffe, did not attend, observers included Ernst Udet and Erhard Milch, Minister of Aircraft Production and Supply; reportedly, neither found its performance particularly impressive. Technically successful as an innovation, the He 178’s top speed was limited to no more than 598 kilometres per hour (372 mph), even when equipped with enhanced HeS 6 engines capable of producing up to 5.8 kN (1,300 lbf) thrust, while its operational endurance during combat scenarios was restricted to merely ten minutes.

Legacy

Heinkel expressed frustration over the minimal official enthusiasm for his privately initiated jet aircraft. In his memoirs, he blamed this on the inability of the Reichsluftfahrtministerium leadership to grasp the benefits of jet propulsion and the significance of the He 178 breakthrough. Despite this lack of external backing, Heinkel proceeded independently to develop a twin-engine jet fighter, applying insights gained from the He 178 prototype’s flight tests. This effort led to the creation of the He 280, recognized as the first jet-powered fighter aircraft prototype. However, it was not a direct evolution of the He 178, since certain design elements—such as embedding the engine within the fuselage—were considered impractical and unsuitable for further refinement.

Unbeknownst to Heinkel, the Reich Air Ministry was simultaneously advancing its own jet propulsion projects. Indeed, by September 1939, orders were given to continue developing single-seat jet aircraft despite a broader directive to reduce non-essential research, aiming to expedite operational readiness of key aircraft models. The jet engines developed by Junkers and BMW diverged significantly from those used in the He 178, favoring an axial flow compressor design over the earlier centrifugal type. Nevertheless, the data obtained from the He 178 program provided valuable experimental insights that greatly supported subsequent advancements.

The airframe of the He 178 V1 was exhibited at Berlin’s Deutsche Luftfahrtsammlung until it was destroyed during an air raid in 1943.

Specifications

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The Heinkel He 178 V2 – featuring an elliptically shaped wing with a trailing edge on the airworthy V1's frame.

See also

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Commemorative plaque recognizing the inaugural jet-powered flight conducted at Heinkel's "Marienehe" factory airstrip, located in the present-day Rostock-Schmarl area

External links

• , featuring rare footage of the Heinkel He 178 alongside audio narrations.