The service life of Russian and Chinese copies of Iran’s MD550 engines recovered from downed Shahed-type drones has proven to be several times shorter than the originals.
The Ukrainian ZAMPOTECH Foundation, which refurbishes these engines for use by the Armed Forces of Ukraine, reported on this.
According to the Foundation, Iranian-made engines typically log 20 or more operating hours. Russian copies last only 4–5 hours, while Chinese versions operate for up to 2 hours.
“The Russian engine runs for a maximum of 4–5 hours – enough for just one or two flights. Only the Chinese engine performs worse: it flies for about 1.5 to 2 hours before seizing completely,” the Foundation shared.
Operating hours denote the actual time an engine runs and are used to plan maintenance and oil changes and to assess engine wear.
The MD550 engine used in Shahed-136 drones is a two-stroke, four-cylinder piston engine.
The Iranian MD550 is a copy of the German Limbach L550 engine, developed in 1987 by Limbach for a narrow niche of motor gliders.
Engine versions intended for Shahed drones usually feature a built-in electric generator to power onboard electronic equipment.
The Foundation also noted that restoring a single Iranian engine requires spare parts from at least three other engines.
“The problem is that there are very few of them, and assembling one working engine requires at least three identical ones,” the Foundation explained.
In 2024, the Russians simplified the design of the engines used in Shahed drones by removing the starter and flywheel.
Such simplification enables cost reduction in engines and, accordingly, the purchase of more components and the production of a larger number of Shahed drones.
