So Express.co.uk asked Alessandra Giovanzanti, senior aviation analyst at Jane’s by IHS Markit, to do a side-by-side comparison of the two aircraft – and we’ve also put together a Top Trumps-style graphic to illustrate their various merits. Ms Giovanzanti said The Su-57 (T-50, PAK-FA) is a single seat, twin engine, multirole fifth generation stealth fighter aircraft, whereas the F-35 was a slightly smaller, single-engine plane. Currently, the Su-57 is a land-based aircraft, with no Vertical Take Off and Landing (VTOL) variant yet developed for ship-borne operations, unlike the F-35B, which would appear to put Russia at a disadvantage.
She added: “There have been talks on the subject since the Russian Navy will need to replace his fighter aircraft fleet with 5th generation capabilities.
“Both aircraft are designed to achieve low observability and employ composite materials in the structure.”
Ms Giovanzanti said the planes which escorted Mr Putin recently were prototypes, of which 11 have been built so far.
She added: “The total requirement is for more than 50 aircraft (76 stated in the latest State Armament Programme 2018-2027).
The first operational unit could enter service in early 2020s.
“There is evidence that the aircraft might receive competitive bidder for programmes in the Middle East and some parts of Asia Pacific, including India and China.”
In addition, Russia may try and step in if the US decides to pull the plug on a deal to sell a fleet of F-35s to Turkey in retaliation at Turkey’s decision to buy Russia’s S-400 missile system.
She said: “Russia has also pitched the Su-57 to Turkey as an alternative to the F-35 for the Turkish fighter aircraft acquisition programme, if Turkey is expelled from the programme.
She added: “Conversely, the F-35 has already achieved a large customer base.
“More than 300 aircraft (all variants) have been delivered so far and 12 countries as customers.”
Vital statistics show little to choose between the two jet fighters.
The Su-57, which is capable of travelling at twice the speed of sound (MACH 2.0), is significantly faster than the F-35, at 1.6 MACH.
The F-35 has a service ceiling – the maximum height at which it can operate – of about 50,000 feet, while the Su-57 can operate at slightly higher altitudes – up to 65,000 feet.
The Su-57 has a maximum take-off weight (the maximum weight at which the pilot is allowed to attempt to take off) of 81,571lb, more than the F-35’s 70,000lb.
It also has a wider range, relating to the distance it can travel between take-off and landing – 2,150 nautical miles, compared of 1,500 for the F-35.
Meanwhile the Su-57 also boasts a slightly wider radius of operation – the distance an aircraft can travel away from its base along a given course with normal load and return without refuelling – of 650 miles, compared with 500 miles for the F-35.