Aviation of the special operations forces of the US Air Force. In a previous publication, Air Force Special Operations of the US Air Force, we examined the tasks and structure of special operations forces, and also got acquainted with the US Air Force MTR aircraft, created on the basis of the military transport C-130 Hercules. Today we will talk about the CV-22B Osprey tiltrotors, designed to support the actions of American special forces.
Creation and adoption of the Osprey tiltrotor
After the failure in 1980 of the operation to free the American hostages in Iran, the leadership of the US Department of Defense expressed interest in an aircraft capable of vertical takeoff and landing and at the same time having a cruising speed and range comparable to the Hercules turboprop. An aircraft that combines the capabilities of an airplane and a helicopter, built under the JVX program (Joint-service Vertical take-off / landing Experimental) jointly by Bell Helicopter and Boeing Helicopters and named V-22 Osprey (eng. Osprey - Osprey), first flew on March 19, 1989.
"Osprey" became the world's first serial tiltrotor - an aircraft capable of vertical takeoff and landing (as helicopters do) and long-term high-speed horizontal flight, typical for conventional aircraft. Since the tiltrotor is not fully a helicopter or an airplane, this also affected its design and appearance. The Osprey is a twin-finned high-wing aircraft powered by two Rolls-Royce T406 turboprop engines located at the wing tips in nacelles that can rotate nearly 98 degrees. The rotation of the nacelles is carried out using a hydraulic drive with a screw mechanism. The propellers with three trapezoidal blades are interconnected by a synchronizing shaft that runs inside the wing. This shaft provides the possibility of controlled flight and landing of the aircraft on one engine. To reduce the size of the aircraft during parking, the wing turns, the propellers are folded. In order to reduce the weight of the structure, about 70% (5700 kg) of the apparatus is made of composite materials based on carbon and fiberglass plastics with an epoxy binder, which makes it about 25% lighter than metal.
From the outset, the turboprop aircraft program, which began in the first half of the 1980s, progressed with great difficulty and was repeatedly threatened with closure. This was due to a large share of fundamentally new technical solutions and a high accident rate of prototypes and the first production copies. A big blow to the project was the US Army's refusal to continue funding. Air Force officials were also critical of the Osprey. The further implementation of the program was insisted by the command of the Marine Corps, which needed to replace the CH-46 Sea Knight helicopters, which were nearing the end of their service life.
The main argument in this case, despite the higher cost, was the multiply increased combat radius and approximately twice the speed of flight in cruise mode, which made it possible to quickly transfer the marines and cargo from the UDC to the landing zone.
After a series of accidents and disasters, most of the problems associated with the technical reliability of the Osprey were resolved, and in 2005 the Pentagon approved a production plan. In 2008, the US military department signed a contract for the supply of 167 V-22 Osprey convertiplanes for a total of $ 10.4 billion. In 2013, the US Department of Defense decided to increase the number of Osprey purchased to 458 units. Of these, 360 are for the USMC, 50 for the Air Force and 48 for the Navy. The cost of one CV-22B, which was put into service by the Special Forces Aviation Command in 2014, was $ 76 million.
Operation of CV-22B tiltrotors of the US Air Force MTR in combat squadrons
The first Osprey was transferred to the 58th Special Operations Wing at Kirtland Air Force Base in New Mexico on March 20, 2006. This machine was used to train pilots and crew members. On November 16, 2006, the US Air Force officially accepted the CV-22B at a ceremony held at Hurlburgh Field, Florida. On October 4, 2007, the tiltrotor was first used in a real search and rescue operation. On March 16, 2009, the Air Force MTR announced that the first six CV-22Bs of the 8th Special Operations Squadron, based at Helbert Field, were ready for combat missions.
In June 2009, Osprey took part in a humanitarian operation in Honduras, delivering about 20 tons of food and medicine to remote villages. In 2009, CV-22B of the 8th squadron was deployed in Iraq, and in 2010 in Afghanistan. On July 3, 2014, CV-22B landed special forces of the Delta Force unit in the vicinity of a militant camp in eastern Syria, where, according to intelligence, hostages were being held. The commandos eliminated the militants on the spot, but found that the hostages had been moved elsewhere and returned home empty-handed. In general, tiltrotors in Iraq and Afghanistan performed well. According to American data, the coefficient of their technical readiness did not fall below 0.6.
According to its characteristics, the CV-22B fully met the requirements of the special operations forces. It was especially noted that Osprey, unlike helicopters, easily crossed mountain ranges, and its range was significantly higher, but at the same time it was more demanding on landing sites.
Design features and characteristics of CV-22B
In terms of weight and dimensions, the CV-22B is close to the heavy special-purpose helicopter MH-53J Pave Low III, decommissioned in 2008, but significantly surpasses it in speed and flight range. The mass of the empty tiltrotor is 15,000 kg. Maximum takeoff weight - 27,440 kg. The weight of the cargo on the external sling is 6140 kg, inside the cargo compartment - 9000 kg. Crew - 4 people. The cabin with dimensions 7, 37x1, 53x1, 3m, volume 24.3m³ can accommodate 24 fully equipped paratroopers or 12 wounded on stretchers with accompanying paratroopers. Service ceiling - 7620 m. Maximum speed in airplane mode - 565 km / h, in helicopter mode - 185 km / h. The wingspan at the ends of the propeller blades is 25, 78 m. The length with the blades folded is 19, 23 m. The width with the blades folded is 5, 64 m. The height along the keels is 5, 38 m.
The CV-22B, used by the Air Force MTR aviation, differs from the MV-22B purchased by the US Marine Corps in more advanced avionics and an increased fuel reserve. The basic version of the avionics CV-22B included the TACAN, VOR / ILS and GPS navigation systems, VHF and HF radio communication equipment, identification systems and night vision equipment. The Osprey was designed using a "glass cockpit" developed for the CH-46X helicopter, which was not put into mass production.
Flight information is displayed on four color displays. The cockpit has a fifth display - for displaying a map of the area. To ensure flights in the mode of following the terrain, there is an AN / ARO-174 radar, which can also be used for mapping the earth's surface. Subsequently, the CV-22B avionics, designed to carry out secret missions over the enemy's territory, have undergone significant improvement, the cabin equipment has been refined and new software has been developed.
Compared to the "Osprey" supplied by the USMC, Special Operations Forces tiltrotors have an increased supply of fuel. The fuel tanks of the MV-22B, designed mainly for the transfer of marines and cargo from universal landing ships, hold 6513 liters of aviation kerosene, and the full refueling of the CV-22B tanks is 7710 liters. In addition, the US Air Force MTR "Osprey" can carry three external fuel tanks with a capacity of 1628 liters. For ferry flights in the cargo compartment, it is possible to install additional fuel tanks with a total fuel capacity of 7235 liters. Combat radius of action without refueling in the air - about 800 km. Ferry range - 3890 km.
Currently, CV-22Bs can receive aviation fuel in flight from all US Air Force MTR tankers, built on the basis of the C-130 turboprop. It also confirmed the ability to refuel from the regular flying tankers of the US Air Force: KC-135, KC-10 and KC-46.
Losses CV-22B
Although after the adoption of the Osprey, all the heavy MH-53 Pave Low helicopters were decommissioned and the MC-130 aircraft were partially supplanted by the special-purpose aviation, the Air Force command had many complaints about the level of technical reliability and flight safety. From the earliest test flights, the Osprey went into disrepute. In various flight accidents, 12 V-22 of various modifications were broken, while 42 people died. Four "Osprey" were lost during the tests, and the rest after being put into service. However, despite a number of serious incidents, the Air Force MTR irretrievably lost only two tiltrotors. On April 9, 2010, as a result of the fall of CV-22B, 3 American servicemen and one civilian were killed, and another 16 Americans were injured. The cause of the disaster was attributed to the pilots' erroneous actions in conditions of poor visibility, loss of situational awareness and high descent rate. On June 13, 2012, CV-22B, which fell as a result of a pilot error in the vicinity of Eglin airbase, could not be restored, but everyone on board survived.
Improving the flight performance and survivability of the CV-22B
At the same time, the CV-22B used by the special forces have repeatedly demonstrated good survivability. For example, in December 2013, three tiltrotors used to evacuate American citizens in South Sudan were damaged by small arms fire from the ground. Subsequently, after returning, 119 holes were counted in their hull, which led to damage to the fuel and hydraulic systems. Despite the damage, the CV-22B were able to continue the controlled flight. In order for the Osprey to cover a distance of 800 km and land at the Entebbe airfield in Uganda, they had to be refueled several times in the air from an MS-130N aircraft.
Based on the results of use in the combat zone, the US Air Force High Command of Special Operations demanded that the CV-22B be revised. To increase combat survivability. First of all, it was necessary to eliminate fuel leakage when the tanks were shot through and to establish ballistic protection of the cockpit and the most vulnerable parts of the structure. In 2015, the first 16 CV-22B MTRs of the US Air Force were equipped with ballistic protection kits, consisting of 66 sintered plates. At the same time, the mass of the armor was 360 kg, with the cost of one set being $ 270,000. In view of the decrease in the payload and the reduction in the flight range, it was decided to equip only Osprey with armor directly participating in hostilities. The drop in flight data that occurred after the installation of the armor was partially compensated for by increasing the power of the AE-1107C engines by 17%. This was achieved thanks to the modernization of the turbine and fuel equipment, while simultaneously updating the software. As a result, the cruising flight speed was increased from 446 to 470 km / h.
Equipping tiltroplanes with weapons and equipment for countering air defense systems
For self-defense of the CV-22B during shelling from the ground, various options for installing weapons were considered. Most often, the Osprey, which flew in Afghanistan and Iraq, mounted 7.62 mm M240 machine guns (American version of the FN MAG) in the tail section, as well as 12.7 mm single-barreled M2 and three-barreled GAU-19s.
In order to increase the strike capabilities, tests were carried out with the AGM-114 Hellfire ATGM, the AGM-176 Griffin small-sized high-precision aviation ammunition and the GBU-53 / B guided bombs. installation GAU-2 V / A, served by the shooter, who had an optoelectronic sighting and search system with a night channel.
However, the IDWS weapons system did not show itself in any way in Afghanistan. First of all, this happened due to the fact that the American command began to plan sorties very carefully, clean up the territory where the special forces landed and accompany the tiltrotors with attack helicopters and attack aircraft. In addition, by that time, the Taliban, having experienced the striking power of American combat aircraft, began to avoid open confrontation. As a result, the main stake in reducing the vulnerability of the CV-22B was made on the booking and installation of advanced passive defensive systems. The upgraded Osprey, operating in the interests of the Special Operations Forces, is equipped with AN / ALQ-211 broadband digital receiving equipment, which, in a difficult electromagnetic environment, analyzes radio frequency emissions and can drop dipole reflectors or use jammers to neutralize threats. Heat traps and the AN / AAQ-24 Nemesis laser countermeasure system are designed to counter missiles aiming at the thermal signature of the engines.
Immediate prospects for the use of convertiplanes in the US Air Force
Although the number of "Osprey" in the US Air Force is relatively small, they play a measuring role in supporting the combat activities of special operations forces. The commissioning of the CV-22B made it possible to retire the MC-130E Combat Talon I aircraft and the MH-53 Pave Low helicopters. Tiltroplanes also noticeably pushed the HH-60G Pave Hawk helicopters into the search and rescue squadrons. It is planned that the more high-speed promising CV-22C converters will operate in conjunction with the HH-60W helicopters, which are planned to replace the HH-60G. For air refueling of MH-60 special forces helicopters and NN-60 search and rescue helicopters in the future, CV-22C should receive refueling equipment similar to that used on KC-130J aircraft. An increase in the flight, operational and combat characteristics of the modernized CV-22C should primarily occur by increasing the engine power by 25% and using more advanced avionics and weapons.
