Seems like the Russians got themselves a cheap stealthy replacement for the Kh-59M.
The Su-57 received two new ammunitions for hitting ground and surface targets.
08/16/2024
Sukhoi continues to work to increase the strike capabilities of the Su-57 fighter and announced the start of production of the new S-71 missile, which is also classified as a strike unmanned aerial vehicle. The ammunition received approval from the Russian Ministry of Defense after changes were made to the design based on the experience of its use in Ukraine. About this reports Aviationweek publication.
The new stealth tactical missile S-71 for hitting static and moving targets was developed by the Tactical Missiles Concern as part of the program to update the ammunition of the Su-57 fighter. A publication by the Sukhoi Design Bureau on the 85th anniversary of its founding states that the weapon is offered in two versions: the S-71K (“Carpet”), a guided air-to-ground missile, and the S-71M (“Monochrome”), a more powerful autonomous UAV. The S-71K product is equipped with cluster munitions. Among several warhead options for the S-71M is a high-explosive shaped charge.
To reduce radar signature, the S-71 has a trapezoidal fuselage, a folding swept wing and a V-shaped all-moving tail. The S-71K ammunition is designed for suspension under the wing of the carrier aircraft; the S-71M version can also be placed in the intra-fuselage weapons compartment of the Su-57 fighter or the S-70 Okhotnik attack UAV.
The product is equipped with a turbojet engine TRDD-50, which is also used in the Kh-59M and Kh-101 missiles. The S-71 flight is carried out by following the terrain at altitudes of 20-75 m above the ground and 5-15 m above water.
“Meanwhile, the weight and dimensions of the product are noticeably smaller than those of the Kh-59MK2. The estimated effective reflective surface of the product is about 0.007-0.01 square meters with a flight speed of 0.95 Mach and a range of 200 - 350 km. The S-71M missile is equipped with a small-sized turbojet bypass engine with a thrust of 175 - 220 kg. The estimated mass of penetrating high-explosive fragmentation warheads can reach 100-150 kg”, – reported in the TG channel “Russian weapons”.
For use in the daytime and at night and to increase the range of the thermal imager, the S-71M UAV is equipped with electro-optical sensors. The Sukhoi company states that the system can be used in conjunction with the operator to guide, check the target selected by the drone and hold it. The platform can also search, detect and engage targets using data stored in the memory of the on-board computer.
“Russian Weapons” notes that to guide the S-71 to a target, an advanced digital inertial navigation system with a GLONASS/GPS correction module, a radar altimeter, and an optical-electronic correlation sensor are used. It is also possible to use bispectral medium- and long-wave ICGSN with operating wavelengths of 3-5 and 8-12 μm, respectively. “The product will be also structurally, software and hardware adapted for use as ammunition in the Su-30SM2 and Su-35S fighters”, the authors of the TG channel believe.
The Sukhoi company patented the configuration of the S-71M UAV in November 2023. The design bureau also reported that the production of control and guidance systems has been transferred to its own enterprises. According to Aviationweek, tests of the S-71 took place in April 2023 in Zhukovsky near Moscow. The first flight with S-71K and S-71M missiles suspended under the wing of a Su-57 fighter was performed on April 18 by test pilot of the Sukhoi Design Bureau Sergei Bogdan.