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One free scan finds every outdated or missing driver and matches the right update for your exact hardware.Free scan · exact hardware matchYes—but only as a proposal. The aircraft was Alexander Lippisch’s P.13a, a late-1944 German interceptor study designed around a ramjet that would burn granulated coal. Germany never completed the powered aircraft, and it never flew. The related DM-1 was an unpowered delta glider built to examine the configuration, not a coal-powered fighter.
What the Lippisch P.13a was
Dr. Alexander Lippisch designed the P.13a during Germany’s late-war search for unconventional interceptors. MiGFlug describes it as a “ramjet-powered delta-wing interceptor (project study)” from 1944, with coal as its intended fuel and a status of “never built as a powered aircraft.”
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The project reflected two urgent problems: Germany needed fast aircraft to intercept Allied bombers, while aviation fuel was under severe pressure. Coal was widely available, so Lippisch’s concept tried to adapt a plentiful solid fuel to a high-speed air-breathing engine. The available accounts establish that fuel-scarcity context, but do not provide a reliable primary statistic for German fuel reserves.
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Coal in a wire-mesh basket
The proposed engine was not a coal-fired piston engine. A basket made from wire mesh, filled with granulated coal, would sit behind the aircraft’s nose intake. A gas burner would ignite the coal before or during operation.
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Airflow supplied the combustion
Once the aircraft was moving rapidly, the intake would force air into the engine. That air would pass through the burning coal, support combustion and heat the resulting gases. The hot, expanding flow would then exit through a rear nozzle to produce thrust.
Why it needed help to get airborne
A ramjet has no compressor driven by a turbine. It relies on the aircraft’s forward speed to compress incoming air, so it cannot produce useful thrust from a standstill. The P.13a therefore would have needed a rocket booster, a tow launch or another assisted takeoff method before its ramjet could operate effectively.
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The distinction is important: “coal-powered” describes the proposed fuel and combustion arrangement, not a successful aircraft that Germany operated.
Was the engine ever tested?
An EAA Chapter 124 newsletter published in June 2017 states that Lippisch planned a coal-burning ramjet and that “This engine was tested but never got into production.” That is a newsletter account, not an independently verified quotation from Lippisch, the Luftwaffe or a German ministry. It supports the conclusion that the propulsion idea reached experimental work, but not production or an installed, flying fighter.
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The DM-1 was not the P.13a
The surviving hardware associated with the concept was the DM-1, an unpowered delta glider. It was intended to investigate the configuration’s low-speed handling and aerodynamic behavior. It did not carry the coal ramjet, and its existence is not evidence that the powered interceptor flew.
Construction was still incomplete when U.S. forces overran the site in 1945. American authorities directed Lippisch’s team to finish the glider and sent it to the National Advisory Committee for Aeronautics (NACA) Langley wind tunnel for postwar study. The DM-1 was therefore a captured and completed test article, while the P.13a remained a project study.
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| Aircraft or component | What it was | Evidence status | Outcome |
|---|---|---|---|
| Lippisch P.13a | Proposed coal-fueled ramjet interceptor | Design study; no powered prototype | Never completed or flown |
| DM-1 | Unpowered delta research glider | Physical test article | Completed under U.S. direction and examined at NACA Langley |
| Coal ramjet | Solid-fuel ramjet concept using granulated coal | Experimental engine work reported | Never entered production |
Did it really reach Mach 2.6?
Not in flight. MiGFlug reports that DVL high-speed wind-tunnel models indicated the sharp delta configuration was stable to approximately Mach 2.6. That figure describes a model-test or predicted stability result. It is not a measured speed for a completed P.13a, because the powered aircraft never flew.
Accordingly, calling the P.13a a “Mach 2.6 fighter” overstates the evidence. The defensible wording is that wind-tunnel models suggested stability around Mach 2.6.
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Why the idea was attractive—and why it remained impractical
The strategic attraction
- Coal was more available than high-grade aviation fuel in Germany’s late-war economy.
- A ramjet’s basic architecture is mechanically simpler than a turbojet because it has no turbine-driven compressor.
- A fast delta interceptor could, in theory, attack bombers before fuel shortages and production constraints made conventional designs untenable.
The operational obstacles
- The aircraft needed assisted launch because the ramjet could not provide static thrust.
- Combustion of solid granules would have to remain stable while the aircraft experienced changing airflow, acceleration and altitude.
- The coal system, intake, burner and nozzle still required development, integration and flight testing that never occurred.
- Germany’s deteriorating military situation left little time to turn an advanced study into a reliable operational aircraft.
How the P.13a compares with a real aircraft program
The P.13a sits at the earliest end of an aviation-development scale. A drawing or wind-tunnel model can show that a shape might be aerodynamically viable; it cannot establish engine reliability, takeoff behavior, controllability throughout a mission or combat usefulness. The DM-1 advanced the evidence one step by providing an unpowered glider, but it still did not validate the coal propulsion system.
| Question | P.13a answer |
|---|---|
| Was there a complete powered prototype? | No; the powered aircraft was never completed. |
| Did it fly? | No. |
| Was coal the intended fuel? | Yes, as granulated coal burned in a proposed ramjet. |
| Could the ramjet take off by itself? | No; assisted launch would have been required. |
| What does Mach 2.6 mean? | Approximate stability indicated by DVL wind-tunnel models, not flight speed. |
| Was the DM-1 the same aircraft? | No; it was an unpowered glider used to study the configuration. |
The accurate bottom line on the “coal-powered Nazi fighter”
The P.13a was a genuine German wartime design study, and its coal-burning ramjet was more than a casual sketch: experimental engine work was reported. But the aircraft itself remained unfinished. The only related airframe, the DM-1, was an unpowered glider later studied by the United States. The project is therefore best understood as an ambitious response to fuel scarcity and interception demands—not as a secret coal jet that entered service or proved its advertised speed in flight.
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