The American F-35 is considered one of the most advanced combat aircraft in the world, but it is equipped with only one engine. The Russian Su-57, on the other hand, received two.
Many believe that two engines are better than one, but in practice, everything depends on the tasks set for the designers.
"Perviy Tekhnicheskiy" figured out why American and Russian engineers came to completely different solutions.
It all started with the vertical takeoff version
When the F-35 was created, the program initially included three versions of the aircraft. The most complex was the F-35B modification for the US Marine Corps, capable of short takeoff and vertical landing.
For this, a huge lift fan had to be placed inside the fuselage. Due to this layout, using a twin-engine scheme became practically impossible.
As a result, a single powerful Pratt & Whitney F135 engine became the common solution for all F-35 variants. Today, it develops thrust of about 19–20 tons with afterburner and remains the most powerful production engine for fighters.
The Russian school traditionally chooses two engines
Since the time of the Su-27, designers have relied on a twin-engine scheme. This path was followed by the Su-30, Su-35, and subsequently the Su-57.
This approach allows for high thrust-to-weight ratio, large fuel capacity, and good characteristics at supersonic speeds. In addition, two engines help maintain control even with serious damage to the aircraft.
It is no coincidence that the American F-22 Raptor, which belongs to the same class of heavy air superiority fighters, is also equipped with two engines.
For Russia, survivability is more important than economy
Another reason is related to geography. Flights over the Arctic, Siberia, and remote areas require maximum reliability.
If one engine fails, a twin-engine aircraft is often able to return to the airfield on its own. For a single-engine aircraft, the consequences of such a failure are significantly more serious.
Ultimately, the debate about the number of engines is meaningless — each aircraft is ideal for its own war. The Americans created a flexible tool for global operations, while Russia created a super-survivable predator for defending its vast skies.