South Korea has targeted the forecast boom in civil requirements for unmanned air vehicles as the basis of its national UAV development strategy

For the past two years, aerospace and government officials in South Korea have been developing a national unmanned air vehicle roadmap aimed at securing a key role in the creation of an international civilian UAV industry over the next eight to 10 years.

The UAV roadmap is being developed as a subset of South Korea's ambitious national technology strategy issued by the ministry of science and technology (MOST) in October 2002.

Key details of the national UAV strategy were released at the first Korean UAV International conference in Busan in early November. The strategy predicts a near doubling of the international UAV market in monetary terms over the next four years, with growth remaining dominated by military requirements in the near- to medium term.

However, South Korean analysts believe that by 2008 the civilian UAV market is likely to be worth almost as much as total international UAV industry was in 1998.

Key market

The UAV roadmap, says Professor Choonbae Park from the Flight Dynamics and Control Laboratory at Inha University, puts priority on the emerging civil market as the key to securing a 5% share of the total international UAV market by 2012. Meeting that objective, Park says, requires South Korea to establish itself as one of the top 10 UAV technology supplier nations within the decade.

The national UAV roadmap calls for that technological base to be created through domestic research and development jointly funded by MOST, the Korean Aerospace Research Institute (KARI) and local industry, but with input from international partners on specific projects. Park is a consultant adviser on UAVs to MOST, which oversees South Korea's overall national technology strategy.

One of the major hurdles to the development of a global civil UAV industry, Park says, is the absence of international standards for both air vehicle design and air traffic management. He says the roadmap identifies a requirement for the South Korean government and aerospace industry to play a high-profile global role in getting those standards established as part of its overall growth strategy. "That will be the only way forward," he says.

Despite the emphasis on civil UAV applications, the roadmap also specifically targets South Korean military requirements, with the national Agency for Defence Development (ADD) playing a key role as a funding source and project sponsor.

The South Korean armed forces have long-term requirements for medium- and high-altitude long endurance (MALE and HALE) UAVs, a divisional level tactical UAV (TUAV), a close-range TUAV for use at regimental level, and a naval vertical take-off and landing (VTOL) UAV. There are also requirements for new decoy UAVs and, in the very long term, a new-generation armed UAV to replace Israel Aircraft Industries Harpy anti-radar systems introduced into operational service with South Korean units in 2000.

Park says South Korea already has a considerable level of UAV capability as a result of previous programmes such as the Beejoe TUAV developed between 1990 and 1999 by ADD and Korea Aerospace Industries (KAI) and now in production as the Night Intruder 300, and a skilled aerospace and information technology sector workforce.

The UAV sector also has reasonably low overheads in terms of market entry Park says. However, he notes that South Korea remains dependent on other nations for subsystems and some core equipment technologies. Park also warns that the roadmap requires South Korea to pursue a variety of advanced technologies and these inherently will present risks.

The UAV roadmap is based on an integrated series of flagship air vehicles and associated technology development. In the near term these comprise a MALE air vehicle programme, the new-generation VTOL air vehicle - known as the Smart UAV - programme established in2002 as part of MOST's "21st century frontier research and development programme", and an unmanned stratospheric airship project. After 2006, Park says, "we need to look at UCAVs [unmanned combat air vehicles]."

Technology programmes

Underlying the air vehicle aspects of the UAV roadmap is a series of associated enabling technology development programmes. In terms of air-vehicle development these include work on integrated flight control systems, including new-generation systems based on satellite GPS and inertial navigation, and reconfigurable control surfaces.

Payload projects include developing miniature synthetic-aperture radar (SAR) and multi-spectral sensing systems. Work on more sophisticated data handling and processing systems is also emphasised. These technologies would be applied on a common basis to each of the specific air vehicle programmes.

As the two flagship projects of the roadmap, considerable resources are being directed into the Smart UAV and stratospheric airship development. Published forward funding commitments for both programmes total $162 million.

The Smart UAV programme is based on a joint development of tiltrotor concepts in partnership with Bell Helicopter with the objective of creating a reliable, high-speed, runway-free, low-operating-cost UAV for the civil market that can operate in controlled airspace. The UAV is also envisaged as performing civil surveillance, exploration, communications relay, disaster survey and environmental management functions.

Bell was selected as a preferred partner for the project late in 2003. This followed a competitive selection process for air vehicle technologies that included evaluation of Boeing's canard rotor wing technology, concepts such as tail sitter and ducted-fan VTOL UAVs, gyrocopters, tilt-body, counter-rotating rotor helicopters and traditional helicopter designs. Associated technologies examined included collision avoidance systems, vehicle health monitoring and self-recovery systems, active stall and noise control systems, and shape adaptive wing structures.

Smart UAV

The Smart UAV project was launched in July 2002 with funding allocated to March 2012 totalling $120 million. In parallel a Smart UAV Development Centre (SUDC) was established as part of KARI with an international call for proposals released shortly afterwards. According to SUDC director Dr Cheol-Ho Lim, the project is structured in three phases. Phase one runs until the end of 2004, with total development spending forecast at $22 million. The phase is intended to explore core technologies and undertake preliminary design and concept validation for the Smart UAV.

Lim told the Busan conference that as well as Bell Helicopter, Phase 1 technology partners include Israel's Elbit, which is supporting systems engineering andintegration activities; Baumann University in Russia; South Korean companies LG Innotec and MteQ; and South Korea's Chungnam, Inha, Chosun and Konkuk universities.

Tiltrotor demonstrator

Phase 2, running from 2005-8, is expected to result in the development of a tilt-rotor demonstrator. Total funding of $54 million has been allocated. Phase 3, running from 2009-12, will support prototypeair-vehicle flight testing and missionevaluation as well as production decisions. This phase is expected to cost $44 million.

Lim says that the air vehicle emerging from Phase 3 is expected to have a baseline endurance of five hours with a payload capacity in excess of 40kg (88lbs). The air vehicle is envisaged as having a maximum speed of 270kt (500km/h) and being able to cruise at 215kt at altitudes of 10,000ft (3,000m) for at least 3h. SUDC estimates indicate that the potential international market for a Smart-type VTOL UAV could grow to $10 billion a year, assuming both civil and military sales.

The unmanned stratospheric airship programme is being lead by KARI with 10m and 50m prototype air vehicles being flown as part of Phase 1 development which began in December 2000 and concluded last August.

The project is intended to result in a 200m unmanned airship powered by solar cells and regenerative fuel cells and optimised for telecommunications relay and Earth observation roles. The airship would have an endurance of over one month. A rival project is under way in Japan.

According to KARI airship development team member Yung-Gyo Lee, the phase one airship budget totalled $8.3 million with KARI flying a 10m prototype early in the programme to test the concept. Lee told the Busan UAV conference that the 50m test variant, designated VIA-50, flew five successful flights between September and November 2003. Test missions are continuing to prove the ability of a system to operate autonomously for more than 3h at 10,000ft. Phase 2 of the programme, which began in December 2003, is intended to result in a prototype airship capable of flying at 65,500ft and remaining on station for more than 72h.

Phase 2, which runs until October 2007, has a budget of $34 million. Of this total, $25 million is to be provided by the South Korean government and $9 million by South Korean companies.

Lee says that the third phase of the programme, to start in 2007, will focus on operational testing of the 200m variant with results being used to guide decisions on subsequent system commercialisation.

As well as the UAV roadmap projects, South Korea's aerospace industry and research institutions are exploring a range of other technology projects. KAI revealed at Busan that it is interested in developing its own naval VTOL system. According to KAI director Dr Seung-Jon Kim, the UAV is still at a conceptual stage, but if it proceeded, development would be completely separate to the Smart UAV effort.

Kim also told the conference that the South Korean army's divisional level TUAV and close-range UAV requirements are potential opportunities for new development programmes by the company.

Night Intruder

Work is also under way within KAI on evolving the Night Intruder 300 system to include automatic take-off and landing, more capable command and control, and increased air vehicle endurance from the current 6h up to around 20h. Development of the long-endurance variant is also expected to feed back into the MALE UAV programme.

KAI last year launched an export drive for the baseline Night Intruder 300 with the Australian Department of Defence's Joint Project 129 tactical unmanned air vehicle requirement targeted as a key export market test.

South Korea's unusually named Y4K Telcom company has been working with Novik 21 Century since December 2001 to develop and market the 4h endurance NMAS UAV, also known as Sky Inspector. The company is targeting civil and military applications in Asia with a small production plant for the air vehicle set up in early in 2003. Y4K Telcom, a joint venture between South Korean, German and Russian interests, was set up in mid-2000.

KARI has been working on long-endurance meteorological UAVs and has been flight testing a prototype 2,000km (1,080nm)-range air vehicle known as Durumi since 2000. The UAV has close design and operational parallels with the Saab/Aerosonde Aerosonde MkIII air vehicle, including the vehicle-roof launching system. However, both KARI and Aerosonde confirm that there are no links between the two programmes.

Major challenge

KARI says that it has carried out more than 30 Durumi flights so far, but the UAV is still developmental. A major challenge, says KARI, has been the development of an effective autopilot system. However, technical breakthroughs in 2003 are expected to result in a system being ready in the first half of this year. Decisions on commercialisation are planned for this year.

Konkuk University is exploring micro air vehicle (MAV) development in parallel to its role on the Smart UAV programme and has flown two MAV systems. MAV 1, known as Spot, is a 150mm (6in) combined wing-body and weighs 75g. It has an endurance of 3min. MAV 2, designated Batwing, has a 130mm flexible composite wing, an underslung fuselage, weighs 60g and has an endurance of 15min. Both systems are remotely controlled.

According to Prof Kwang-Joon Yoon, director of the National Research Laboratory for Active Structures and Materials at Konkuk University, the institute is now moving towards development of biomimetic MAVs, with these expected to be commonplace within 15 years.

Yoon says current research priorities being pursued by Konkuk include artificial muscles, possibly based on piezo-electric actuation, and micro-electrical mechanical systems based gyroscope and accelerometer for MAV attitude and position control.

Potential breakthroughs

Such systems, Yoon told the Busanconference, offer potential for "breakthroughs quite unlike those seen to date"in international MAV development. Fully autonomous MAVs with wingspans of around 300-500mm, Yoon forecasts, are likely within 10 years. However, achieving full autonomy on air vehicles with 150mm wingspans is likely to remain a challenge.

Source: Flight International