VTI QMS-50 Seabird: Difference between revisions
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| QMS-50 Seabird | |
|---|---|
| |
| Navalized QMS-50AM1 Gannet in multi-role configuration. | |
| Role | Utility helicopter |
| Manufacturer | Vertical Technologies, Inc. |
| First flight | 17 November 1989 |
| Introduction | 1999 |
| Status | In service |
| Primary users | Army of Carthage Punic Navy Carthage Air Forces |
| Produced | 1989–present |
| Number built | about 13,500 |
| Unit cost |
NSD$19.5 million (flyaway cost, (FY2008))
|
The VTI QMS-50 Seabird is a medium-lift helicopter family developed and produced by Vertical Technologies, Inc. for military and civilian use. The original design was developed for the Punic Navy in the late 1980s and early 1990s as a utility helicopter to replace the older HMR-49 Fregata in the vertical replenishment, CSAR, minesweeping, and light anti-surface role. The original QMS-50 Tern variant was was selected over competitors for its three-engine layout and greater lifting capacity, and was introduced into naval service in 1995.
The basic QMS-50 design was later further developed into anti-submarine variants for naval service as well as more advanced variants for both the Army of Carthage as well as the Carthage Air Forces. The QMS-50AM1 Gannet is a development of the original QMS-50 Tern incorporating a ducted propeller, and is the first compound helicopter in Carthaginian service. The QMU-50 Petrel is a further development incorporating folding wings to provide a significant increase in speed and range for Army and Air Forces use. Civilian models of all three variants have been demonstrated and are in limited use by law enforcement and diplomatic protection agencies.
History
QMS-50 Tern
In 1979, the Punic Navy issued a request for proposals for a new utility helicopter to replace the HMR-49 Fregata for the purposes of vertical replenishment, personnel transport, and light anti-surface work. The Fregata fleet had been worked hard during the Northern War and the following period of reconstruction, resulting in rising accident rates and growing maintenance costs. Operations in the North Atlantic also required the HMR-49 fleet to undertake missions outside of its expected climate range, and the Fregata demonstrated significantly reduced readiness rates in the rough weather and cold climate. The original requirement specified a three-engine design to rectify these shortcomings, along with improved cold-weather capabilities, greater payload, and increased range. In addition, the design was not to exceed the hangar dimensions of the HMR-49, in order to assure compatibility with existing infrastructure.
Six proposals were submitted to the Navy in 1980, including designs from Vertical Technologies (VTI), Cordoba Helicopters, Elissa-Arishat VertiSys (EAVS), and Mehmud-Tabnit Aircraft Systems (MTAS). All included the requested three-engine powerplant and extended range, and early signals indicated the Navy might choose several contractors to provide flying prototypes for more in-depth tests. Although the initial program was only for the procurement of utility models, defense analysts widely speculated that the contract winner would be the frontrunner in future competitions to replace the Navy's anti-submarine and commando helicopters, leading to a fiercely contested proposal phase. In 1981, the Navy approved the VTI and EAVS proposals to proceed to the flying prototype stage, and both companies were to supply eight demonstration models for testing by June 1987.
Both companies provided their prototypes ahead of schedule, with VTI providing their Seabird demonstrator in March 1987 and EAVS providing their demonstrators in May. The flight testing and evaluation period began in September after a period of maintenance familiarization, inspection, and pilot training. In 1989, the Navy announced their decision, awarding the contract for full production to VTI for up to 600 helicopters in the first production batch. Despite a formal protest by EAVS, the Navy upheld its decision and early pre-production airframes entered production in 1992 to allow a broader range of environmental and operational tests.
The first helicopters entered service in 1996 as the QMS-50 Tern, progressively replacing existing HMR-49 Fregata medium-lift helicopters. The last Fregatas were removed from active service in 2003 and all remaining inventory transferred to reserve storage, training use, or cannibalized for parts.
Advanced Compound Helicopter program
Following the conclusion of the testing period in 1994, the initial VTI prototypes were transferred to the Navy Aerospace Research Laboratory (NARL) for use in the Advanced Compound Helicopter program. In conjunction with VTI, the demonstrators were used as the basis for experiments in developing a compound helicopter capable of greater speeds than conventional designs, without the size and complexity of a tiltrotor or tiltwing design. Three test vehicles were converted to use a ducted propeller, providing improved forward thrust without significantly affecting aircraft weight. In 1998, another three helicopters were tested with a new folding wing mechanism designed to reduce the effects of retreating blade stall on helicopter speeds.
The final two helicopters were used in a separate program testing new powerplant arrangements, including high-efficiency turboshaft arrangements using the new Numidian Kinetics TSK-300-1700-series engine coupled with a lighter-weight multi-speed gearbox and the more radical ZFI Technology TCZ-X300-1700 turbo-compound engine. A new rotor design providing greater lift and lower weight was also trialed with both engines.
The ACH program concluded in 2003, having demonstrated the success of the individual components. However, as the QMS-50 Tern was already in production and met the Navy's requirements, the technologies tested in the ACH program were not adopted by the Navy for the original Tern order.
Army adoption
In 2003, the Army of Carthage issued a separate request for proposals for a new medium utility helicopter to replace the aging HMA-45 Fulmar, dubbed the Tactical Transport Helicopter. Proposal requirements included space for at least 25 combat troops seated, an external sling load capability of at least 5,000 kilograms (11,000 lb), a combat radius of at least 600 kilometers (370 mi) and the ability to fit into an RTS-221 Raven tactical airlifter in a stowed configuration. Provisions for ballistic armor to protect troops in combat, as well as the ability to provide full defensive weapon coverage including active countermeasures were also required. Competitors were preferred to provide improved range, speed, and payload beyond program requirements, but strict budget caps were to be enforced.
During the requirement evaluation phase, Army engineers were allowed to observe the ACH program demonstrations, and following a period of evaluation and analysis, an ACH-derived three-engine powerplant was mandated, a first in Army service. Despite the performance characteristics of the turbo-compound engine, the Army favored the more conventional turboshaft plant, due to a lower perceived risk. In response to the request, eight proposals were received, most being variants of the previous Navy program. In spite of the powerplant requirement, SSCI Aerospace submitted their twin-engine tiltrotor for consideration, although the proposal was not pursued by the Army. The VTI proposal was based on the original QMS-50 Tern, incorporating the technologies developed under the ACH program, including the folding wings and ducted fan. Other entrants included similar compound designs as well as proposals with coaxial rotors.
In 2004, the Army approved the VTI and MTAS proposals for further development. The VTI proposal had been renamed to the QMU-50 Petrel to distinguish the design from its naval predecessor, now possessing folding wings and a ducted fan. In this configuration, the proposed design promised speeds in excess of 400 km/h (250 mph), significant greater than conventional helicopters. The MTAS proposal used coaxial rotors and smaller, non-folding stub wings with ducted fans to provide similar speeds, but eliminated the tail boom entirely. Four prototypes of each design were funded for trials and evaluation.
The VTI proposal was declared the winner in 2006, over protests that VTI had unfairly benefited from collaboration and funding in the ACH program. In spite of these protests, the Army moved forward with its planned procurement order until the program was temporarily placed on hold pending an investigation into the contracting process. The Army and VTI were cleared of any wrongdoing in late 2007, with production resuming in early 2008. Initial production batches were delivered to to the Army beginning in 2009, replacing HMA-45s in high-readiness aviation brigades.
Having selected the QMS-50 Tern as a replacement for the HMR-49 Fregata utility helicopter, the Navy looked to replace its anti-submarine helicopters with a higher-performance design with increased endurance and greater lifting capacity for modern sensors. In 2004, the Navy issued a request for proposals for the Anti-Submarine Modernization Program, with similar endurance and payload requirements to those in the previous request. Defense analysts considered the request to be a mere formality, as VTI was already heavily-favored to be the winner due to the Navy's use of the QMS-50 Tern. As expected, VTI submitted a modified version of the Seabird, designated the QMS-50AM1 Gannet and incorporating the folding wings and ducted fan of the Army QMU-50 Petrel variant. VTI was announced as the winner in January of 2007, following a politically contentious struggle against allegations of improper contracting procedure.
In 2010, the Navy issued a contract to VTI and EAVS for modification work on existing QMS-50 Tern aircraft, to modernize the aircraft for commonality with the QMS-50AM1 Gannet. The program includes re-engining with the new TSK-300-1700 turboshafts, improved gearbox, and new avionics but does not include the folding wing system or ducted fan. 300 aircraft are expected to be refurbished per year, beginning with the oldest types in service.
The first QMS-50AM1 Gannets entered service in 2014, providing a significant improvement in capability over the previous HMR-49S ASW variant. In addition to a greater payload capacity, longer range, and better reliability, the QMS-50AM1 carries more advanced sensors and compatibility with unmanned vehicles, allowing the QMS-50AM1 to make better use of offboard remote sensors for ASW operations. The HMR-49S is expected to be fully retired by 2019.
Design
The QMS-50 uses a conventional helicopter layout and is designed for easy modification to address a range of requirements. The Seabird family incorporates more advanced avionics, rotor blades, and composites into its design, reducing weight and improving performance over legacy designs. The fuselage is primarily constructed of composites and aluminum-lithium alloys for reduced weight and vulnerability to corrosion. The fuselage dimensions were dictated by the design requirement to fit within the payload bay of the RTS-221 Raven and RTS-223 Razorbill tactical airlifters, although this requires that the rotor blades and wings to be removed. Fully stowed and unloaded, two QMS-50s may be carried by either tactical airlifter. Designed for operational theaters ranging from the Sahara Desert to the north Atlantic, the QMS-50 is able to operate in temperatures ranging between −45 to +50 °C, and can remain stable in inclement weather, including crosswinds up to 75 km/h (47 mph).
The Seabird family incorporates a glass cockpit using a series of six multi-function displays for the flight instruments. Flight controls are provided for both pilots but the QMS-50 may be flown by a single person. Military variants may include forward-looking infrared for night operations, connected either to the pilots' helmet-mounted display or to a separate, additional mapping/IR display. The cockpit is designed to withstand impacts up to 10 m/s (33 ft/s) and the pilot seats are armored for protection. An active vibration control system is used to reduce fatigue on the airframe as well as improve crew and passenger comfort.
Propulsion
The QMS-50 is powered by three Numidian Kinetics TSK-300-series turboshaft engines. Early engines provided 1,570 kW (2,110 hp), but current-model engines provide up to 1,700 kW (2,300 hp) each. The decision to use three engines over the conventional two-engine layout was taken to reduce the danger in the event of a single-engine out situation, particularly dangerous to helicopters operating in less hospitable environments. The TSK-300 series engine was developed for dual use in the ANH program and the projected Army FVS initiative, and is derived from the civilian ST410 engine.
The engines are connected to a lightweight gearbox developed by the Navy Aerospace Research Laboratory, offsetting the additional weight of the third engine. The gearbox uses quill shafts and face gears for power transmission, significantly improving the torque handling capability of the gearbox without increasing weight. A second driveshaft provides power to the rear rotor or ducted fan. The gearbox drives a five-bladed 18.8-meter (62 ft) main rotor, with blades designed to reduce vibration and acoustic signature. The blade construction is also designed to reduce weight while easing maintenance requirements, being composed of a composite honeycomb structure with a protective titanium leading edge. The blades and tail rotor may be folded in naval models for shipboard stowage. Unlike the rest of the helicopter which was designed by Vertical Technologies, the drive system including gearbox and rotor blades were developed by NARL and later integrated into the QMS-50 design.
Fuel is stored in a series of four self-sealing 1,100-liter (290 U.S. gal) fuel tanks located under the floor, feeding into a small holding tank above the engines in the powerplant housing. This holding tank allows the engines to operate for a short time using gravity-fed fuel in the event of damage or malfunction in the primary fuel pumps, although all tanks use separate redundant fuel pumps to ensure reliability. Additional fuel tanks may be added to extended-range variants, and external fuel tanks can be carried on the Modular Stores System wings to further increase range. An aerial refueling boom may also be fitted.
Compound rotor
Beginning with the QMU-50 Petrel introduced in 2005 for Army, QMS-50-series helicopters purchased for the Carthage Defense Forces have used vectored-thrust ducted fans instead of conventional tail rotors. The ducted fan is designed for use in conjunction with the folding wings fielded on Army and Air Forces models, which provides relief from retreating blade stall and allows the QMU-50 to reach speeds much greater than would be attainable in a conventional helicopter. The wings can pivot in pitch to assist in flight control and to reduce rotor download in a hovering position. They may be folded and stowed when the helicopter is not in use, but must be removed for transport via tactical airlifter.
Using a combination of the ducted fan and wings, the QMU-50 is capable of speeds in excess of 230 knots (430 km/h; 260 mph), with the main rotor slowed to reduce drag and lift primarily provided by the wings. This configuration also reduces fuel consumption at speed, extending the Petrel's range.
The upgraded naval variant introduced alongside the QMU-50, the QMS-50AM1 Gannet, retains the ducted fan for compatibility and increased speed but lacks the folding wings to reduce stowage space requirements, and as a result is limited to 180 knots (330 km/h; 210 mph).
Armament
The QMS-50 is designed to carry a range of armaments on a pair of removable Modular Stores System wings, ranging from light and heavy machine guns to torpedoes, rockets, and air-to-surface and air-to-air missiles. Each MSS wing includes two hardpoints for air-to-surface ordnance and two wingtip stations for light air-to-air ordnance. Up to 1,600 kilograms (3,500 lb) of stores may be carried in total, allowing for a substantial munitions load.
Five points for fuselage-mounted machine guns are available, covering both doors, the rear ramp, and two windows. Both door mounts are compatible with the G/IMG-121 12.7 mm heavy machine gun, while the rest are designed for use with general purpose machine guns such as the G/AMG-77. This arrangement provides a wide field of fire for self defense. In addition, a chin-mounted turret is available for installation, connected to the pilots' stations.
Military and some civilian variants of the QMS-50 series are equipped with self-protection systems including chaff and flare dispensers, directed infrared countermeasures, laser warning receivers and radar- and IR-based MAWS. Army variants and naval special forces variants are equipped with aramid ballistic armor for protection against small-arms fire.
Avionics
The initial QMS-50 Tern was equipped with an advanced computerized flight system, including four-axis autopilot and stabilization systems to reduce pilot workload and a maintenance diagnostic system to reduce maintenance requirements. Newer variants use improved versions of this basic system, and all variants are designed for multi-layer redundancy and benign failure modes. Navigation systems include an onboard inertial navigation system and satellite navigation, and military and civilian instrument landing systems. For safety, obstacle and terrain avoidance systems as well as flight data recorders are also equipped.
Special forces variants may include more powerful multi-mode radar for terrain-following capabilities as well as more advanced detection systems and countermeasures. All cockpit displays and controls are designed to be compatible with night-vision equipment to enable all-weather operations.
Anti-submarine
The anti-submarine QMS-50AM1S Gannet variant can be equipped with a variety of sensors for the anti-submarine and anti-surface roles. The AW/ESS-1134 Nation Blue surface search radar is mounted ventrally and is capable of tracking targets at ranges up to 50 kilometers (31 mi; 27 nmi) in a full 360° circle around the helicopter, including low-signature targets such as drones, small boats, and submarine periscopes. The onboard FLIR is capable of passively detecting periscopes and other heat signatures.
Two ten-tube rotary sonobuoy launchers can be mounted in the main cabin, launching their buoys downward through floor ports. An additional eight sonobuoys may be carried in a rack in the cabin to replenish the rotary launchers. The AW/EST-847 low-frequency dipping sonar can also be mounted, providing a higher-resolution supplement to the sonobuoys. A cable-mounted magnetic anomaly detector is also available, trailed out of the rear cargo ramp and can be used to detect submarines operating near the surface.
The ASW equipment is managed by a pair of operators using modular consoles located just behind the cockpit. The mission consoles feature full-color multi-function displays and are designed to accept future upgrades. The current ASW suite incorporates significant improvements in shallow-water capability and greatly expanded signal processing capabilities. When fully equipped for ASW operations, space remains available for up to three additional personnel plus one litter in the main cabin, enabling the QMS-50AM1S to undertake emergency rescue operations. Most of the ASW equipment with the exception of the Nation Blue radar but including the mission consoles may be removed, opening the cabin up for cargo use.
Crew and cargo
The standard crew for a QMS-50 utility variant is two pilots plus one crew chief/gunner, although specialized variants have other arrangements. Anti-submarine variants have a crew of four, composed of two pilots and two sensor operators while MEDEVAC variants include medics to tend to the wounded. Pilot workload is reduced thanks to the sophisticated autopilot, enabling missions to be flown largely hands-off.
The fuselage has an internal volume of 32 cubic meters (1,100 cu ft), a significant increase over the HMR-49. The cargo compartment is 6.5 meters (21 ft) in length, 2.3 meters (7.5 ft) meters wide, and 1.91 meters (6.3 ft) high, providing space for 24 seated or 45 standing combat troops. Up to 16 stretchers may be accommodated in MEDEVAC variants, and standard FS220A pallets may be accommodated, eliminating the need to break them down during transfer.
The rear ramp can support weights in excess of 3,000 kilograms (6,600 lb), allowing light vehicles to be driven directly into the cargo area. For special operations, compact RHIBs may also be driven directly onto the ramp for quick extraction, and the lower fuselage is watertight for this purpose (although the helicopter itself is not amphibious). A single-man folding door is fitted to the left side of the aircraft, and a larger sliding cargo door is fitted to the right side. Flush tie-down points are mounted in the floor to secure cargo during flight and a light rescue winch is mounted near the right-side cargo door. An external cargo hook may be installed, rated for loads up to 5,500 kilograms (12,100 lb).
Specifications (QMU-50 Petrel)
General characteristics
- Crew: 2 pilots (flight crew) with 2 crew chiefs/gunners
- Capacity: 30 seated or 45 standing combat troops or 6,000 kg (13,000 lb) internally or 5,500 kg (12,100 lb) externally or 16 stretchers
- Length: 20.76 m (68.1 ft)
- Fuselage length: 18.73 m (61.5 ft)
- Fuselage width: 2.8 m (9.2 ft) ()
- Rotor diameter: 18.8 m (62 ft) ()
- Height: 5.8 m (19 ft) ()
- Disc area: 277.6 m2 (2,988 sq ft) ()
- Empty weight: 10,750 kg (23,700 lb) ()
- Loaded weight: 14,500 kg (32,000 lb) ()
- Max. takeoff weight: 16,650 kg (36,710 lb) ()
- Powerplant: 3 × Numidian Kinetics TSK-300-1860 turboshafts, 1,860 kW (2,490 hp) () each
Performance
- Never exceed speed: 245 kn (282 mph; 454 km/h)
- Maximum speed: 230 kn (260 mph; 430 km/h)
- Cruise speed: 210 kn (240 mph; 390 km/h)
- Combat radius: 850 km (530 mi) ()
- Ferry range: 2,500 km (1,600 mi) () with auxiliary fuel tanks
- Service ceiling: 5,700 m (18,700 ft) ()
- Rate of climb: 10.2 m/s (2,010 ft/min) ()
- Disc loading: 7.19 lb/ft² (35.4 kg/m²)
- Power/mass: 0.192 hp/lb (158 W/kg)
Armament
- Guns:
- 2 × 7 mm (0.28 in) G/AMG-77 machine guns or
- 2 × 7 mm (0.28 in) CRA-336 chain gun or
- 2 × 15.5 mm (0.61 in) CRA-334 revolver cannon or
- Hardpoints: 4, 2 per MSS stub wing + 2 wing-tip stations and provisions to carry combinations of:
- Rockets: 70 mm (2.75 in) LGU-710 Scarlet rockets
- Missiles: SGM-741 Takane MMW/laser guided missiles, SAI-774 Sayaka air-to-air missiles, SWT-740 Super Perseid lightweight torpedo
- Bombs: Dandelion mine dispersal system