Some 8,000 units were manufactured by Junkers in Germany late in World War II, powering the Messerschmitt Me 262 fighter and the Arado Ar 234 reconnaissance/bomber, along with prototypes, including the Horten Ho 229.

Schelp responded by stating that Dr Anselm Franz, then in charge of Junkers' turbo- and supercharger development, would be perfect for the job.

The axial-flow compressor not only had excellent performance, about 78% efficient in "real world" conditions, but it also had a smaller cross-section, important for high-speed aircraft.

Dr. Bruno Bruckman's old assistant on the jet engine program, Dr. Österich, took over for him in Berlin, and selected the axial flow design, due to its smaller diameter;[1] it was 10 cm (3.9 in) less than the competing axial-flow BMW 003.

Franz's conservative approach came under question from the RLM, but was vindicated when even given the developmental problems that it was to face, the 004 entered production and service well ahead of the BMW 003, its more technologically advanced but slightly lower thrust competitor (7.83 kN/1,760 lbf).

Max Bentele, as an Air Ministry consulting engineer with a background in turbocharger vibrations, assisted in solving the problem.

The 004 used an eight-stage axial-flow compressor, with six[7] straight-through combustion chambers (made from sheet steel), and a one-stage turbine with hollow blades.

All the hot metal parts, including the combustion chamber, were changed to mild steel protected by an aluminum coating, and the hollow turbine blades were produced from folded and welded Cromadur alloy (12% chromium, 18% manganese, and 70% iron) developed by Krupp, and cooled by compressed air "bled" from the compressor.

[4] Jumo tried a variety of compressor blades, beginning with solid steel, later hollow sheet metal ones, welded on the taper, with their roots fitted over rhomboidal studs on the turbine wheel, to which they were pinned and brazed.

Two small gasoline/oil mix tanks were fitted within the upper perimeter of the annular intake's sheet metal housing for fuelling the starter.

His solution was to raise the frequency, by increasing the blade taper and shortening them by 1 millimetre, and to reduce the operating speed of the engine[6] from 9,000 to 8,700 rpm.

[4] The plug moved about 40 cm (16 inch) fore-and-aft, using an electric motor-powered rack-and-pinion, to change the exhaust cross-sectional area for thrust control.

The compressor and turbine blades' life could be extended by re-balancing the rotors during routine maintenance; the Riedel two-stroke starter engine and the turbojet's governor would also be examined and replaced as needed.

A number of examples of the Jumo 004 turbojet exist in aviation museums and historical collections in North America, Europe and Australia, including; Data from [citation needed] Comparable engines Related lists