|Rare Glimpse Of Russia’s Future Cruise Missile
Aviation Week & Space Technology
12/03/2007, page 26
Russia advances new air-launched deterrent as glimpses of design emerge
Russia may be in a position to begin refurbishing its air-launched strategic nuclear arsenal around the turn of the decade if it sustains the present pace of development and testing on a successor to the Kh-55 (AS-15 Kent) cruise missile.
There is renewed impetus to the follow-on to the Kh-55—Tactical Missile Systems’ Kh-101/102—with increased funding apparently being provided to conclude the long-running program.
The first images of the Kh-101/102’s shape offer an intriguing glimpse of the missile and its general configuration. The design suggests that Russia may have overcome what was previously a significant hurdle in developing its next-generation strategic strike weapon. The Kh-101 is a conventionally armed weapon, while the Kh-102 is the nuclear variant.
The photo (top of p. 27) appears to be of a captive-carry shape-representative test article of the Kh-101/102. The weapon was designed by Raduga, which is now part of Russia’s Tactical Missile Corp.
The weapon’s shape and other design elements clearly show that stealth is a central feature of the cruise missile. For example, it seems to have a semi-recessed or flush intake for its turbofan engine. The intake appears to be less than halfway along the length of the fuselage from the nose of the weapon. It’s not clear where the wing is recessed. Neither the Russian defense ministry nor industry has been willing to provide publicly even the most basic information on the program.
Russia previously struggled with meeting the original range requirements for its strategic cruise weapons. The Raduga Kh-55 (AS-15 Kent) was fitted with a drop-down turbojet engine to improve its overall efficiency; however, the initial variant did not satisfy the Russian air force’s range needs.
The first version of the Kh-55 (AS-15A) was introduced into service with long-range aviation units in 1986. Development was also already underway on the AS-15B to address range deficiencies in the basic missile version. The AS-15A had a range of around 2,500 km. (1,550 mi.), while the AS-15B, which carried additional fuel in slipper tanks, could fly 3,000 km.
When initially conceived in the late 1980s, the Kh-101/102 was to have featured an open-rotor fan engine fitted to the rear of the tri-form control surfaces. This propulsion approach offers significantly improved fuel efficiency, and was likely selected in order to meet the 5,000-km. design specification range for the weapon. U.S. cruise missile designers had also looked at this type of engine concept for strategic weapons during a similar timeframe.
Radar-cross-section representative mockups of the missile fitted with an open-rotor engine are believed to have been ground tested in the early 1990s; however, development problems with the propulsion unit appear to have forced a reevaluation.
The propfan approach and, similarly, an external engine configuration both compromise efforts to reduce a missile’s radar cross section. In the case of the Kh-55, the engine is recessed in the rear fuselage to allow for internal carriage on a rotary launcher. Following release, the engine is then deployed fully into the airflow. While this improves engine performance, it also provides a significant radar-reflective element, and almost certainly increases the missile’s radar cross section.
What appears to be a chin intake on the Kh-101/102 would indicate that the engine is housed within the rear section of the fuselage. The missile is also substantially larger than the Kh-55. While the AS-15 is slightly more than 6 meters (19.5 ft.) long, the Kh-101/102 is about 8 meters in length. While it can be carried internally on a Tupolev Tu-160 Blackjack, the missile is too large for the Tu-95 Bear’s internal bay.
The greater length almost certainly provides for increased fuel capacity compared with the Kh-55.
The image above was likely taken during captive-carry trials of a full loadout of mock Kh-101/102s on a Tu-95 in mid-2006. The aircraft carried eight missiles on four two-station pylons. Late production models of the Bear could carry up to three Kh-55s on each external pylon. The Tu-160 Blackjack may be able to carry up to 12 Kh-101/102s internally.
The Kh-101/102 is thought to use an electro-optical package for terminal guidance. Whether this is a forward-looking system housed behind the RCS-shaped nose, or on the forward under-side of the missile, is not yet apparent. If the former, then the nose-section cover would be discarded in the final phase of the engagement.