russian sources have claimed that Ukraine's Fire Point FP-5 Flamingo cruise missiles are now appearing with a different engine. Whereas earlier versions reportedly used the AI-25TL turbojet, some recently recovered missile debris allegedly indicates the use of a British-made engine instead.
The claim is based on an analysis of missile fragments recovered by russian forces and was highlighted by a Ukrainian defense-focused Telegram channel.
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From Defense Express' perspective, delivering a 1-ton warhead over a range of more than 3,000 km (compared with the Tomahawk's roughly 450-kg warhead and 1,600-km range) virtually requires a full-size turbojet engine. The best-known version of the FP-5 Flamingo has been powered by the AI-25TL, which produces 16.9 kN of thrust and weighs approximately 350 kg. The engine is widely known as the standard powerplant of the L-39 Albatros jet trainer.
As Defense Express noted about a year ago, the AI-25TL was the most likely choice for the missile. At the same time, it was also expected to become the program's primary production bottleneck and one of the two principal compromises resulting from the requirement to combine an exceptionally long range with a very heavy warhead.
The missile's designers were evidently aware of this limitation as well. That is likely why the FP-5 Flamingo carries its engine above the fuselage rather than integrating it into the airframe. This configuration allows the engine to be replaced with relatively minor modifications to the missile itself.
In the Western market, there are roughly five non-afterburning turbojet engines producing around 17 kN of thrust while weighing 300-400 kg. Most have similar, and often even smaller, dimensions than the AI-25TL. Based on the information released so far, either russian analysts have not yet identified the specific British engine involved, or, more likely, that information has simply not become widely available.
Regardless of which British engine is currently being installed in the FP-5 Flamingo, another suitable benchmark is the American Honeywell TFE731-2/3/4/5 family.
Depending on the variant, the TFE731 produces 15.6-19.1 kN of thrust while weighing 337-386 kg. It is also roughly one meter shorter and 15 cm narrower than the AI-25TL, making it approximately 30% shorter and 17% slimmer.
The engine is widely used in business jets, with more than 9,000 units produced to date. That production scale suggests that sourcing the engine in significant numbers would not be impossible.
Perhaps the most important advantage of the TFE731, like many Western engines, is its substantially better fuel efficiency. For the TFE731-3, whose thrust is very close to that of the AI-25TL, fuel consumption is up to 15% lower under comparable flight conditions. If a similar improvement were achieved on the FP-5 Flamingo, its declared range of 3,000 km could theoretically increase by approximately 450 km, assuming the same fuel load and payload
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