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The Challenge
Military forces are constantly seeking ways to dominate operational space 24 hours a day in all environments. This presents huge technical and human challenges, not least of which are experienced by rotary wing aviation. My intent is to describe our current difficulties, majoring on the problems of piloting aircraft in extreme environments, give a résumé of newly developed capability, look to the future and present a challenge to our industrial partners. This requires us to examine three distinct areas; surveillance, targeting and pilotage. All have specific needs, both in terms of technology and training, and all present unique challenges to both helicopter operators and industry.
Current helicopter operations in Afghanistan require us to fly in virtually any conditions. Weather extremes are the norm, ranging from minus 25 to plus 50 degrees celcius across our area of operations. These variations have a marked effect on aircraft and human performance and reduce the effectiveness of aircraft sensors. Then there is the harsh physical environment; every take-off and landing away from a firm base exposes the aircraft and its systems to a battering from highly abrasive dust. These factors make operating 24/7/365 extremely difficult, however, to provide our ground troops with the seamless rotary wing support they need and deserve, we must continue to strive to overcome them.
Surveillance Capability
Rotary wing surveillance capability is well-advanced. It is predominantly focused on electro-optical (EO) and Infra-Red (IR) equipment, an area in which we routinely see rapid technological advances. EO/IR devices are installed on many of our medium and light helicopters, including Sea King, Puma, Lynx and Merlin, with the Army’s light fixed wing aircraft being ideally suited. Our Royal Navy, Army Air Corps and Royal Air Force aircrew have capitalised on extensive corporate experience in Northern Ireland and have developed excellent modern tactics, techniques and procedures for the use of EO/IR equipment. In addition to the EO/IR capability, which can be down-linked in real-time to ground troops, a number of our aircraft are fitted with an Infra-Red Laser Illumination capability, or “Sparkle”, visible only through Night Vision Goggles (NVG). All these devices offer outstanding situational awareness. Coupled to the man-in-the-loop, in this case rotary wing aircrew who are ‘in the mind’ of the ground commander, helicopters provide ‘eagle eyes’ and ‘sharp ears’ that add another battle-winning dimension to land operations.
True round the clock surveillance comes from systems that offer a dual capability; optical (within the visual waveband) and thermal imagery (TI). Rotary wing operations in Iraq and Afghanistan have shown that state-of-the-art EO/IR devices not only enhance operational capability, they also save lives. The ‘eye in the sky’ gives our forces the edge over our enemies, while also ensuring that identification of friend, foe or non-combatant is more effective, thus minimising collateral damage.
Future developments in airborne surveillance will see further improvements to TI equipment, offering still greater stand-off ranges and thus operational security, while incorporating technologies such as Synthetic Aperture Radar (SAR). As they increase in ability, these systems will help us to fight the very current and much-publicised battle against Improvised Explosive Devices (IEDs). We need to see what the enemy is up to but, if that is not always possible, we need equipment that will allow us to see where he has been and to be able to analyse his activity. Technology added to flexible rotary wing platforms, coupled with effective training, will enhance operational effect and save lives.
Targeting
The Apache AH1 provides the Joint Helicopter Command’s principal targeting capability. All UK Apaches carry the Fire Control Radar (FCR) atop the main rotor mast. While the FCR was designed principally for anti-tank operations, it has proved invaluable in the fight against the Taliban. The value of standing-off (possibly completely out of sight and earshot), while tracking moving vehicles, cannot be underestimated. The FCR allows for precision engagement of insurgent vehicles and, like the EO/IR devices previously discussed, reduces the chances of collateral damage, while avoiding accidental engagement of friendly forces and civilians.
The Apache relies upon the Target Acquisition and Designation System (TADS) as its primary surveillance and targeting device. The Forward Looking Infra-Red (FLIR) component allows effective targeting day and night in most weather conditions. However, the legacy TADS has experienced significant limitations and unreliability. Furthermore, pilots have frequently had difficulty gaining clear and positive target identification. For example, to confirm that a man on the ground was definitely carrying a weapon could, in certain environmental conditions, have required the crew to close to within less than one kilometre. The result is a marked loss of operational security and, as UK Rules of Engagement in Afghanistan require positive identification of combatants before opening fire, insurgents would frequently walk away to fight another day. All UK Apache helicopters are currently being upgraded. Capitalising on the US Army buy of the highly reliable and totally re-vamped Lockheed-Martin Modernised TADS (M-TADS), we are fitting all our Apaches with this vastly improved system. Already installed on all of our forward fleet aircraft, M-TADS has a new generation FLIR, which provides a crystal clear image, even in poor weather conditions. It allows aircrew to stand well back from potential targets, increasing surprise and improving security, while ensuring that positive target identification is assured. In the year that we have already operated M-TADS in Afghanistan, we have seen a marked improvement in operational effect and greatly enhanced safety for our own troops and non-combatants.
Pilotage
We can equip our helicopters with state-of-the-art targeting and surveillance sensors and weapons that hit their targets with pin-point precision. However, unless the aircraft can operate throughout the night and in a variety of extremely challenging environmental conditions, these are of little consequence. The two principal areas for improvement in this capability are Rotary Wing Red Illumination and Low Visibility Landing. While these are two discrete difficulties faced by battlefield helicopter pilots, they are inextricably linked, and many of the current and potential solutions help to tackle both.
Rotary Wing Red Illumination Capability (RRIC) and Brownout
With the exception of the Apache, where the pilots night fly using their M-TADS FLIR as the primary source of reference, UK battlefield helicopter pilots rely upon Image Intensification (II) Night Vision Goggles (NVG) to transit the battle space and to take off and land at unlit sites. In order to provide aircrew with ground references, NVG rely upon some ambient light, usually from the moon or from reflected cultural lighting. When ambient light levels are below 10 millilux (the Red Illumination period), rotary wing NVG operations are particularly challenging, notably in rural Afghanistan, which has negligible cultural lighting, and where the weather is frequently poor. To mitigate these factors, our aircrew undergo a stringent training regime. However, further technical advances will further help to improve capability and safety in this area.
Arguably the biggest challenge facing battlefield helicopter pilots, perhaps even more than facing enemy fire, is that of Low Visibility Landing (LVL). Whenever an aircraft lands at or lifts from an un-prepared site in the desert, it is rapidly enveloped in a thick cloud of re-circulating dust and sand; a phenomenon pilots call “Brownout”. Within seconds the pilot loses most or even all external references. This occurs when the aircraft is in motion and close to the ground, the most dangerous phase of flight. At night, with a pilot wholly reliant on the monochrome, 40 degree field-of-view afforded by NVG, the problem is greatly exaggerated. In recent years the Joint Helicopter Command has seen extensive damage to those aircraft that have impacted the ground while in Brownout conditions both in Iraq and Afghanistan. Due to their role, it is our troop-carrying Support Helicopters, notably the Chinook, Merlin and Puma, that are particularly prone. It is testament to our training regime and the tenacity of these crews that Red Illumination and LVL operations are so successfully executed.
Recent Developments
The immediately available solution to the RRIC/LVL challenge has been to fit some of our aircraft fleet with FLIR, with the image displayed on a screen in the cockpit. FLIR measures minute temperature differences and in no way requires ambient light. In rural areas of Afghanistan, it has proved to be a truly excellent aid to night pilotage. All our operational battlefield helicopters are flown with two front seat crew, and the FLIR allows the handling pilot to fly ‘head-up’ without having to refer to instruments inside the cockpit, continuing to use NVG as the reference, while the non-handling pilot monitors the FLIR and provides a running commentary to the handling-pilot. Thus the low-level phases of low ambient light sorties can now be conducted in greatly improved safety. A bonus of FLIR is that it does partially penetrate the Brownout dust cloud. While it is not designed for this purpose, and this benefit is limited, it still gives rotary wing aircrew a further layer of safety.
An additional development is the installation of Display NVG (DNVG) onto battlefield helicopters. For the last few years these expensive items were the province of specialist aircrew only. However, recognising the additional safety benefits, we have designated them as part of the Theatre Entry Standard for all battlefield helicopters deploying to Afghanistan. Working around the complex technicalities of integrating such devices onto helicopters, a programme is underway to fit all forward fleet aircraft for the system and physically install it onto those deploying on operations. DNVG allow the overlay of vital flight information onto the NVG, directly in the pilot’s eye-line, enabling crews to keep their eyes out of the cockpit during the safety-critical phases of low-level flight, yet still able to monitor key instrumentation such as height, rate of climb or descent, aircraft attitude and speed, engine performance and vital navigational data.
The result of installing FLIR and DNVG on our support helicopters is an improved operational capability, notably for aircraft providing the Immediate Response Team. The real significance of this is that the systems offer a genuinely life-saving capability. Firstly our aircrew are now operating in a far safer manner under very challenging circumstances. Moreover, ground troops can now place an even greater reliance upon support helicopters to bring medical support in quick time, in almost all conditions, guaranteeing that severely wounded soldiers can be rapidly evacuated to full medical facilities within the “golden hour”.
New Developments – Conformal Symbology
In recent years industry has been striving to provide ever better situational awareness to military pilots and much R&D effort has been expended cracking the RRIC/LVL nut. A reasonably mature development is Conformal Symbology (CS). To use CS a pilot must identify a landing site, with no need for prior knowledge. It can be selected from a map or aerial photograph, or could be chosen at the last minute before a crew elects to land. The position is then GPS fixed and CS overlays a generic ‘virtual landing site’ onto the pilot’s display. This virtual image remains locked on the GPS position of the chosen location. Even if during the approach Brownout obscures all external references, the pilot still has his virtual site to which he can approach and land.
In August 2009 a Lynx from 667 (Development and Trails) Squadron Army Air Corps performed the world’s first successful live trial of CS. Using DNVG as the medium for displaying the symbology, the pilot was hooded, so that he could see nothing beyond his NVG from which he could gain references – no view of the outside world at all. He flew the aircraft in a series of landings, circuits and take-offs, solely reliant upon CS and the aircraft height, speed and attitude indications on the DNVG. At no stage did the safety pilot in the other seat need to take control of the aircraft. Full integration onto an operational aircraft will prove complex, and we have yet to tackle display problems. However, once these are resolved, CS should offer a significant reduction in danger to aircrew experiencing Brownout.
Long-Term Solutions and Sensory Overload
Our industrial partners are committing massive effort and resource into tackling head-on the RRIC and LVL problems. The fleet-wide addition of DNVG, vast improvements in FLIR performance and CS have all helped us to take large strides in terms of operational effect and flight safety. However, the battle has not yet been won, especially in the area of Brownout. R&D activity is looking at yet further improvements to the equipments listed above, while new innovations continue to excite and to capture the imagination. Increasing the quality of head-up displays, along with rapid advances in helmet-tracking technology, will further enhance situational awareness, increase field of view and improve the quality of the image upon which aircrew rely to pilot their aircraft safely. Medium term solutions include systems that will merge FLIR and SAR imagery to create a continually-updating synthetic (but reality-based) image of the landing site. Long-term ideas include the science-fiction-like concept of Retinal-Projection, where imagery and information will be projected directly into the pilot’s eye, theoretically offering a 360 degree field of view.
Some developments are very close to perfection and are simply in need of trials on aircraft and operational evaluation by military pilots, while others are the stuff of the deep future. However, my major concern is that of Sensory Overload. Every system mentioned so far, be it for surveillance, targeting or pilotage, relies 100% on inputting information into the human eye. This requires the visual and motor cortices in the brain to take in, recognise, process and then react to each piece of information. This is a complex activity, taking the human brain between 1.5 and 1.8 seconds to produce a reaction.
Imagine a crew responding to a short-notice task. They are under pressure to evacuate a seriously wounded soldier, it is dark and light levels are low, the weather is marginal, neither pilot has visited the landing site before and Brownout is an inevitability. Add to these pressures the fact that, as the aircraft approaches the casualty’s location, the enemy opens fire with heavy machine guns and rocket-propelled grenades. An extreme set of circumstances, but one in which our Support Helicopter pilots in Afghanistan routinely find themselves. The pilot’s brain is vastly overloaded both in terms of data and emotion, yet he must then process a set of complex visual data just to land safely. Under such pressure, his brain could simply eliminate one or more data inputs; one of which could be that which would otherwise keep the aircraft from crashing.
A challenge to industry
Please continue to produce the excellent systems we already have which render our operational flying even safer, and also keep up the outstanding R&D activity that will provide better situational awareness and fidelity. However, please remember not to overlook the other human senses. The US Army’s Aviation Medicine specialists, in conjunction with the UK’s, have spent much time developing tactile systems. These do not need to tap into the brain’s busy cerebral cortex. A human touching a hot surface and rapidly snapping his or her hand away constitutes a primitive action, using the top of the spinal cord, much under-used by a seated pilot, and not even engaging the over-loaded parts of the brain. As opposed to the 1.5 to 1.8 seconds for a complex action, a primitive action will take between 0.25 and 0.5 seconds. Another innovation is that of 360 degree sound, relayed to the pilot through the headset, to indicate where information (such as hostile fire) is coming from. This system will use the brain’s auditory cortex. While this also requires time to process information, it is an area that is less heavily loaded than the visual cortex and its use will help to reduce pressure on the pilot’s over-worked internal processor.
In the future battlefield helicopters will genuinely “own the night”, not just parts of it. Technological developments, coupled to our ever-improving training regime, are ensuring that we maintain the edge in all environmental conditions and every year we “own” ever more of the night. We must carry on working closely with our industrial partners to ensure that we continue to eliminate gaps in our operational capability, while further enhancing flight safety.
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