The Me 262 flew on its jets in July 1942, first met Allied aircraft in late July 1944 and fought in unit strength from October, and for the pilots who met it, it was a glimpse of the next war. Nothing with a propeller could catch it. Its engines were built from mild steel because Germany had no nickel to spare, and needed an overhaul after ten to twenty-five hours of running, sooner if handled roughly; its pilots were few and its fuel was scarce; and Allied fighters learned to wait over its runways, where it was slow and helpless. Fourteen hundred were built and about three hundred fought. It changed nothing about how the war ended, and everything about what came after.
870 km/hTop speed1,430 (~300 fought)Built
2· WHY IT MATTERED
Speed became a different game
A propeller loses its grip as its blade tips approach the speed of sound: its efficiency collapses, and at the same time the airframe runs into the drag rise of compressibility. Between them they capped piston fighters at roughly 700 km/h in level flight however much power they had. A turbojet removes the propeller limit, and the Me 262’s wing and engines pushed the airframe limit further. It cruised where a Mustang could only dive, and every fast aircraft since has followed it.
Its four 30 mm MK 108 cannon could put about 14 kg of shells a second out of the muzzles, six times a Mustang’s figure (a measure of what leaves the guns, not of what hits), and a handful of hits would take a bomber apart. The shells were slow and the guns emptied in eight seconds, so pilots closed fast and fired late. Racks of R4M rockets, fired from outside the bombers’ gun range, were added in 1945.
Two Jumo 004s gave only 17.6 kN of static thrust for a six-tonne aircraft, and the engine flamed out or burned its turbine if the throttle was moved quickly, so the 262 gathered speed slowly from a standing start. On take-off and landing the 262 could neither run nor turn, and Allied fighters loitered over its airfields to catch it there. Hitler’s insistence on a bomber role complicated priorities, and historians still argue over how much it delayed the fighter; engine life, fuel, pilot conversion and airfields under attack were the larger limits.
5· THE ENGINE
A turbojet made of the wrong metal
The Jumo 004 was the first axial-flow turbojet in production, the layout nearly every jet engine has used since. Its prototypes used nickel, cobalt and molybdenum that the blockade had cut off, so the production engine replaced them with aluminium-coated mild steel and hollow turbine blades folded from a chromium-manganese sheet and cooled with air bled from the compressor. It took 375 man-hours to build against 1,400 for a BMW 801 radial, and it lasted a working day. Move the throttle too quickly and it flamed out; move it faster and the turbine burned.
2× Junkers Jumo 004B · axial turbojet · 8-stage compressor, 6 combustors, 1-stage turbine · 8.8 kN each · 719 kg · overhaul after 10 to 25 hours
The MK 108 was a short, cheap, blowback cannon firing a 330-gram mine shell at only 500 m/s: hopeless at long range, devastating close in. Four of them gave the Me 262 the heaviest armament of any fighter of the war, for as long as the ammunition lasted. Against bombers it worked. Against a Mustang that could turn inside it, the cannon rarely got the chance.
7· TRY IT
Jet against propeller: where the curves cross
The lab plots the power a propeller can put into the air against speed, collapsing as its tips approach the speed of sound, against a jet whose thrust barely falls with speed, so its power available keeps climbing. Where the curves cross is where the jet starts to win; below it the propeller is the better machine, which is also why the 262 was so sluggish on take-off. The Jumo itself runs live on the engine card.
Readout
At 500 km/hthe propeller wins
Propeller efficiency83%
Crossover~600 km/h
Shapes, not certified data: the propeller curve carries a
tip-shock collapse near 650 km/h, the jet’s power available grows
with speed because its thrust barely falls. Every 1944 dogfight
report lives in the gap between those lines.
8· THE LAB
Power, guns and range: the same three models for all ten
Power against altitude from the type of supercharger, weight of fire against the other nine, and Breguet range with the armour and drop-tank trades. Simplified models, each scaled to this aircraft’s published figures, so the shapes are honest and the third decimal is not.
Messerschmitt Me 262: 14.30 kg/s, of which 100 % from cannon; 8 seconds of fire.
Readout
Weight of fire14.30 kg/s
Cannon share100 %
Seconds of fire8 s
Metal in this burst28.6 kg
Messerschmitt Me 262: the guns as carried on the reference variant; seconds of fire is the gun that runs dry first. A bomber never brought every gun to bear on one attacker.
Messerschmitt Me 262, 9 of 10
Deep dive · A jet engine without nickel· opened from Messerschmitt Me 262
Timelines · WW2 aircraft · go deeper · Messerschmitt Me 262
A jet engine without nickel1944
The first production turbojet was built from mild steel, and lasted a working day.
8.8 kN·719 kg·10–25 h·375 man-hours
01The idea
Hollow turbine blades folded from sheet, cooled with compressor air, running near their melting point
A turbine blade lives in gas hotter than the metal it is made of would like, spinning fast enough that its own weight pulls on it with tonnes of force. The alloys that survive that are heavy with nickel, cobalt and chromium — the metals a blockaded Germany did not have. The production Jumo 004B was redesigned around what it did have, and it worked, briefly.
02Why it matters
Hollow blades from a sheet
The turbine blades were folded and welded from a chromium-manganese steel sheet, hollow, with compressor air blown through them to keep the metal below the gas temperature. The combustion cans were aluminium-coated mild steel. The engine took 375 man-hours to build against 1,400 for a piston radial, and cost a tenth as much.
03Why it matters
The resonance
In late 1943 blades began to fail in flight. Max Bentele found that the blades’ natural frequency fell in the engine’s running range and they were being shaken to death; he shortened and tapered them and lowered the speed from 9,000 to 8,700 rpm. The failures stopped. The life did not get much longer.
04Why it matters
Ten hours, twenty-five with care
A Jumo 004 was overhauled after ten to twenty-five hours; a careful pilot who moved the throttle slowly might double that. The same axial layout, in nickel superalloys with the same cooled hollow blades, now runs for tens of thousands of hours in every airliner engine. The idea was right. The metal was not there.
05Try it
The Jumo, live
The site’s turbojet demo preset to the Jumo 004: weak compressor, wartime turbine limit.
Readout
At 500 km/hthe propeller wins
Propeller efficiency83%
Crossover~600 km/h
Shapes, not certified data: the propeller curve carries a
tip-shock collapse near 650 km/h, the jet’s power available grows
with speed because its thrust barely falls. Every 1944 dogfight
report lives in the gap between those lines.