Sophisticated simulation technology is being used to train US Air Force crews for covert operations.

Graham Warwick/ATLANTA

ALBUQUERQUE, NEW Mexico - this year's venue for the annual convocation of the simulation industry - is home to probably the world's most advanced flight-simulation centre. The 58th Special Operations Wing (SOW), Kirtland AFB, produces combat-ready crews for US Air Force Special Operations Command using a highly integrated training system all the more remarkable because it was acquired piece-by-piece.

In putting the system together, the unit achieved several firsts: in producing fully correlated visual and sensor image-generator databases; in simulating the global-positioning system (GPS); in networking high-fidelity simulators for mission rehearsal; and in using virtual-reality helmet displays for aircrew training.

The system has been acquired with unusual speed, a result of the decision to use a small-team approach reminiscent of Lockheed Martin's "Skunk Works" programme-management style. Aircraft and simulators were procured through Air Force Air Logistics Centers more usually tasked with supporting in-service systems, rather than through normal channels.

Kirtland trains pilots, flight engineers and aerial gunners for five special-forces aircraft types: the Sikorsky MH-53J Pave Low IIIE and MH-60G Pave Hawk, Lockheed Martin HC-130P Combat Shadow and MC-130H Combat Talon II and the Bell UH-1N. The MH-53J and MH-60G are among the most sophisticated helicopters in service anywhere, and their special-operations mission requires crews to be trained in the use of correlated sensors, night-vision goggles (NVGs), and integrated navigation systems at low level, at night, in adverse weather and in a hostile environment.


Electronic classrooms

Delivery of the first MH-53J in July 1987 caused a significant change in training methods at Kirtland, where blackboards, slide projectors and simple simulators were being used to train students. The almost-overnight infusion of high-technology helicopters required the introduction of electronic classrooms, computer-based training, part-task trainers and sophisticated simulators.

Aggressive modification and acquisition schedules for the MH-53Js and MH-60Gs required concurrent delivery of the training systems. The MH-53J weapon-system trainer (WST) was ready for training at Kirtland in July 1990, 31 months after contract award; the MH-60G WST was ready for training in October 1992, 27 months after contract award. Both devices were delivered by GE Aerospace, now part of Lockheed Martin.

In addition to the MH-53J and MH-60G WSTs, the Kirtland campus now houses an HC-130P WST, MH-60G and TH-53A operational flight-trainers (OFT), MH-53J and HC-130P part-task trainers (PTT) and a reconfigurable MH-53J/60G aerial gunner and scanner simulator (AGSS). An MC-130H WST and loadmaster and aerial-refuelling PTTs are due to be introduced.

The MH-53J and MH-60G WSTs and TH-53A OFT are connected to the SOF-NET inter-simulator network, enabling students to "fly" dissimilar formations and rehearse multi-ship tactics. The TH-53A OFT can act as an aggressor helicopter, for training in defensive air-combat manoeuvres. The HC-130P WST is now being added to the network, enabling crews to practice aerial refuelling, and the AGSS, MH-60G OFT and MC-130H WST will follow in 1996.



The 58th SOW has described the MH-53J WST as " of the most successful and sophisticated training devices in the world". The device, which served as a model for the later MH-60G WST, simulates the complete Pave Low avionics suite, including multi-mode radar, forward-looking infra-red (FLIR), integrated Doppler/inertial/GPS navigation, radar- and missile-warning receivers, and infra-red and electronic countermeasures.

Mounted on a six-axis motion system, the simulator cab has positions for two pilots, one flight engineer and two instructors. An eight-channel Lockheed Martin Compu-Scene V image-generator drives collimated displays at the forward, side and chin windows and generates FLIR images. Visual scenes, cockpit lighting and the two touch-screen instructor stations are all compatible with image-intensifying NVGs.

An integrated electronic-combat simulation system (IECSS), developed by TRW, provides a "real-world" environment in which a threat can actually shoot down an aircraft if the trainee does not use the correct tactics or countermeasures. The threat simulation includes an assessment of the effectiveness of the countermeasures employed and of the damage sustained if the aircraft is "hit".

Effective use of the simulator for training and for mission rehearsal requires fully correlated visual, radar, FLIR and navigation databases - so that the terrain pilots see on their displays matches what they see through the windows. Early experience with the MH-53J WST showed the need for more detailed, real-world, databases and resulted in a decision to upgrade the image generator to the high-resolution, photo-textured Compu-Scene V.

Identical Compu-Scene V visual systems on the MH-53J and MH-60G WSTs and TH-53A OFT have been networked so that the power of three image generators can be concentrated on one simulator to triple the feature density for mission rehearsal. Under a new support contract, Lockheed Martin will upgrade the image generators and install panoramic display systems similar to that used on the MH-60G OFT.

The MH-60G OFT, produced by Camber (formerly SBS Engineering), is a fixed-base device providing a fully correlated visual, sensor and navigation simulation. The image generator - a six-channel Compu-Scene PT2000 - is being updated to a standard comparable with the Compu-Scene V, the HC-130P WST having already been upgraded with a Compu-Scene V visual.


Aerial gunners

The AGSS, built by Binghamton Simulator, is designed to train aerial gunners in NVG scanning techniques. The motion-base simulator represents the rear cabin of an MH-53J or MH-60G, complete with 7.62mm mini-guns and 12.7mm machine guns and computer scanning. Trainees wear helmet-mounted displays linked to Compu-Scene SE1000 image-generators which simulate NVGs.

The AGSS can stand alone or be integrated with the MH-53J or MH-60G WST via the inter-simulator network to allow full-crew operation. The visuals are correlated so that what the pilot sees the rear-ramp gunner will see a few seconds later. For mission rehearsal, the helmet displays can be driven by the more powerful Compu-Scene V.

An on-site rapid database-generation system was acquired in 1990 along with the MH-53J WST. This contractor-run operation soon grew to be the largest of its kind in the US Department of Defense and now has 24 Lockheed Martin personnel. The company says the programme has generated some 4.1 million km2 of visual and radar databases since 1990.

Satellite, aerial and hand-held photographs, maps, charts, blueprints and solid models are digitised and combined with digital terrain-elevation and cultural-feature data to create correlated geo-centric, photo-specific, NVG-compatible visual, infra-red and radar databases. A single production effort results in multiple database formats.

Lockheed Martin has demonstrated the capability of updating existing databases with the additional detail and features required for mission rehearsal within 72h . New photo-specific databases can be produced from scratch within five days.



Linking simulators to the SOF-NET network enables several "aircraft" to operate within the same database, each visible to the others. This is accomplished via a Systran SCRAMNet fibre-optic local-area network and a technique known as "reflective memory", which gives each simulator access to the data required to model the other players in its visual system.

At the same time, electronic-combat simulation allows the aircraft to be operated within the same threat environment. Each of the WSTs has its own IECSS, but for a networked simulation one is designated the "master". The master IECSS is responsible for deciding which threats are active and targeting those threats against individual aircraft on the network. Each "slave" IECSS is then responsible for deciding which of the local threats can actually see the aircraft, using terrain-occulting data from the radar simulation, and for simulating weapon trajectories, determining the effectiveness of countermeasures and assessing aircraft damage.

Each simulated mission can encompass up to 25 threat scenarios - each with up to 400 unique threats of which 64 can be active at any one time. Threats can either detect and engage targets autonomously or operate under a command-and-control structure which is simulated by the master IECSS. The master system can also send interceptors after individual aircraft.

At the heart of the Kirtland network is the training observation centre (TOC). This 41-seat theatre is used as both an electronic classroom and a scenario-control centre. Occupants can observe up to eight simulators operating on the network via large-screen displays of the visual scenes and sensor images from each, and on a projected digital map showing the threat locations and aircraft routes.

A commercial-quality television recording studio integrated directly with the simulators records visual scenes, sensor images and radio communications, while cockpit-mounted cameras record crew activities and intercom audio. These videos can be replayed in the TOC for training or to review mission rehearsals, or sent out to the special-operations squadrons for in-unit training.

Seven workstations in the TOC allow personnel to communicate with the simulators and to role-play, becoming survivors needing rescue or enemy personnel jamming communications. A Corps-level battlefield-simulation system has recently been added to the TOC, enabling piloted simulators to interact with computer-generated forces. Once a wargame scenario has been set up, entities generated by the battle simulation, such as tanks, appear in the simulators' visual systems as three-dimensional models.

The eighth SOF-NET node is a distributed interactive simulation (DIS) gateway. This enables simulators on the Kirtland network to participate in simulations under way elsewhere, even over long distances. The DIS link was demonstrated in 1994 when the SOF-NET was connected to a theatre-level battlefield simulation at Hurlburt Field, Florida.



MH-53J crews trained at Kirtland first saw action in the 1991 Gulf War, and the consensus is that crews with simulator training came highly qualified and were ready to fly combat missions within an average of 20h - some after only two flights - compared with 50-60h for crews without simulator training.

The introduction of simulation technology has resulted in an MH-563J combat-crew qualification programme where 31 of the 62 training flights are conducted in the simulator. In the final Pave Low integrated sensor-operations phase, 18 2h night flights in the aircraft have been replaced by 13 simulator sessions and three aircraft sorties.

The Kirtland campus continues to grow. A $9.5 million expansion is under way, with construction of a six-bay simulator building and a 150-seat auditorium for conferences, training and network observation. The Loral-built MC-130H WST is scheduled to arrive in January and further simulators - and simulation firsts - are on the horizon for 58 SOW.

Source: Flight International