RuAviation

Sukhoi continues its work to increase the strike capabilities of the Su-57 fighter and has announced the start of production of the new S-71 missile, which is also classified as a strike drone. The munition received approval from the Russian Ministry of Defence after design changes based on its experience in Ukraine. This is reported by the Aviationweek.com publication.

The new S-71 low-observable tactical missile for hitting static and moving targets was developed by the Tactical Missile Armament Concern as part of the Su-57 fighter’s ammunition upgrade programme. The Sukhoi Design Bureau’s publication for the 85th anniversary of its foundation states that the weapon is offered in two variants: the S-71K (Carpet), an air-to-ground guided missile, and the S-71M (Monochrome), a more powerful autonomous UAV. The S-71K is equipped with cluster munitions. Among the several warhead options of the S-71M is the fragmentation-fragmentation shaped charge.

To reduce radar visibility, the S-71 has a trapezoidal fuselage, a folding sweeping wing and a V-shaped all-turn tailplane. The S-71K munition is designed to be suspended under the wing of the carrier aircraft, while the S-71M version can also be placed in the intrafuselage weapons compartment of the Su-57 fighter or the S-70 Hunter strike UAV.

The product is equipped with the TRDD-50 turbojet engine, which is also used in the Kh-59M and Kh-101 missiles. The S-71 flight is carried out with terrain envelopment at altitudes of 20-75 metres above the ground and 5-15 – above water.

‘Meanwhile, the mass and dimensional parameters of the product are noticeably smaller than those of the Kh-59MK2. The estimated EOP [effective reflective surface area] of the product is of the order of 0.007-0.01 square metres at a flight speed of 0.95M and a range of 200 – 350km. The S-71M missile is equipped with a small-size turbojet twin-circuit engine with a thrust of 175 – 220 kg. The estimated mass of the penetrator-penetrator-fuzed projectile can reach 100-150 kg,’ the Russian Weapons TG channel reported.

The S-71M UAV is equipped with electro-optical sensors for day and night time use and to increase its thermal imaging range. Sukhoi says the system can be used in conjunction with an operator for targeting, verifying the target selected by the drone and holding it. The platform can also search, detect and engage the target using data stored in the memory of the on-board calculator.

Russian Weapons notes that the S-71 uses a promising digital inertial navigation system with a GLONASS/GPS correction module, a radar altimeter, and an optoelectronic correlation sensor for targeting. It is also possible to use bispectral medium- and long-wavelength ICGSN with operating wavelengths of 3-5 and 8-12 microns, respectively. ‘The product will be structurally and hardware-software adapted for use in the combat package of Su-30SM2 and Su-35S fighters,’ the authors of the TG-channel believe.

The configuration of the S-71M UAV was patented by Sukhoi in November 2023. The Design Bureau also said that production of the product’s control and guidance systems has been moved to its own facilities. According to Aviationweek, the S-71 was tested in April 2023 in Zhukovsky near Moscow. The first flight with S-71K and S-71M missiles suspended under the wing of the Su-57 fighter was performed on 18 April by Sukhoi Design Bureau test pilot Sergei Bogdan.