The KAI KUH-1 Surion is a twin-engine, transport utility helicopter developed primarily by Korea Aerospace Industries (KAI), Agency for Defense Development (ADD) and Korea Aerospace Research Institute (KARI) jointly with Eurocopter. In 2006, the research and development phase of the Korea Helicopter Project - Korea Utility Helicopter (KHP-KUH), costing around , was launched by the Agency for Defense Development. In 2012, full-scale production of the Surion began. KAI is the principal manufacturer of the type.

An initial force of around 245 Surions have been ordered by the Republic of Korea Army to replace their aging fleets of UH-1H utility helicopters and 500MD light utility helicopters, which have been in service for decades. KAI will also construct civilian and law enforcement variants of the helicopter.

In 2017, the Surion was the centerpiece of an embezzlement scandal involving parent company KAI, the South Korean Ministry of National Defense and its Defense Acquisition Program Administration.

Development

Origins In December 2005, the South Korean government appointed Eurocopter as the primary partner to KAI for the then-formative Korea Helicopter Project - Korea Utility Helicopter (KHP-KUH). In June 2006, KAI and Eurocopter won the KHP-KUH research and development contract from the Defense Acquisition Program Administration (DAPA) to start the project. It remains Seoul's biggest arms deal ever with a non-US company. The development of the aircraft was funded 84% by the South Korean government and 16% by Korea Aerospace Industries (KAI) and Eurocopter. At the time, it was the biggest South Korean defense contract to be issued to a non-American defense company.

A production contract worth about is expected to be signed around 2011 before the start of mass production. Eurocopter took a stake of 30 percent in the 2006-2012 development phase and 20 percent in the following ten-year production phase, KAI and the South Korean government held the remaining stakes in the program. As the prime sub-contractor, Eurocopter has provided technical assistance in part for developing the power transmission, main gearbox, boom and tail gearboxes, automatic flight control system and rotor mast. Eurocopter experts were dispatched to KAI premises in Sacheon, South Korea, to provide support and teach KAI engineers state of the art processes and technologies for the design and manufacture of helicopters.

In June 2008, KAI announced that the first prototype KUH was to be rolled in the following month and that ground tests would begin later that year. The firm stated that it aimed to conduct the type's first flight in early 2010 and for the first production aircraft to be delivered in 2013.Govindasamy, Siva. "PARIS AIR SHOW: Korea Aerospace to roll out utility helicopter prototype in July." Flight International, 14 June 2009. In August 2009, the first prototype was unveiled by President Lee Myung-bak at an unveiling ceremony in Sacheon. In October 2009, it was announced that the program was to be delayed as the result of several ministries having received reduced budgets as greater priority had been placed on social welfare programs; the Ministry of National Defense announced that stability of existing defense programs had been assured.

On 10 March 2010, KAI announced that a prototype had performed the maiden flight of the Surion. Two test pilots and an engineer performed a series of taxiing and hovering maneuvers, as well as a stationary hover at 30 ft (9.1m), during this initial flight.Donald, David. "Korea's Surion Helicopter Flies." AIN Online, 15 March 2010.Francis, Leithan. "PICTURES: Korea Utility Helicopter makes first flight." Flight International, 16 March 2010. In May 2010, following three months of flight testing, the prototype performed its first public flight demonstration."Korea Utility Helicopter demonstrates capabilities." Korea Times, 22 May 2010. In January 2011, Eurocopter and KAI established a joint venture, KAI-EC, for the purposes of marketing the Surion and handling export sales. At the time, it was envisioned that 250-300 units would be sold worldwide by 2021."Eurocopter reinforces its commitment to strengthen the Republic of Korea's aerospace industry, and highlights the Surion and its naval derivative." Vertical, 19 October 2011. In December 2012, deliveries of the first Surion model began. In February 2013, low temperature testing in Alaska, United States, was completed, leading to development of the KUH-1 Surion being formally recognized as completed in March."History." KAI, Retrieved: 23 June 2016.

Further development

The KUH-1 Surion served as the basis for a navalised derivative, the Korean Naval Helicopter (KNH). By 2011, the KNH had entered into the development stage; work was being performed on the project by a partnership between KAI, Eurocopter, and Elbit Systems. In January 2016, following completion of development work on the amphibious variant of the Surion, the variant was cleared to enter production later that year.Perrett, Bradley."Marines Version OF KAI Surion Ready For Production." Aviation Week, 5 January 2016.Maass, Ryan. "KAI completes Surion-variant helicopter development." United Press International, 29 December 2015.

Specialised models and derivatives of the KUH-1 have been proposed. In October 2009, KAI revealed that it was studying the potential for developing an indigenous attack helicopter based upon the KUH platform as one available option for meeting an established Korean Army requirement for a new attack helicopter (AH-X). This variant was reportedly to possibly share up to 70 per cent component commonality with the base KUH version.Govindasamy, Siva. "KAI reveals options for army attack helicopter." Flight International, 21 October 2009. In December 2015, the Korea Forest Service and Jeju Fire Safety Headquarters, the largest civil government helicopter operator, ordered a firefighting and EMS version of the KUH-1 Surion; this requires a special airworthiness certificate."South Korea Forestry Service Orders Surion; Russia Protests." Rotor &Wing, 1 December 2015.

In 2014, DAPA's Board of Audit and Inspection begun an investigation into the level of indigenous technology used on the Surion. The investigation revealed that the technology transfer arrangement with Airbus Helicopters only covered 134 out of the 450 components used in the rotorcraft's power delivery system. Amid allegations of a breach of contract, Airbus Helicopters responded that it had honoured the contractual terms."Local helicopter manufacturing is expensive flop." Korea JoongAng Daily, 22 December 2014.

In October 2015, KAI announced plans to increase production of the Surion from one helicopter per month to three per month in 2016.KAI readies to boost Surion production in 2016 - Flightglobal.com, 23 October 2015

Between 2011 and 2016, the National Aerospace Laboratory of the Netherlands conducted a technology demonstration program under contract from KAI of an experimental fly-by-wire flight control system for the Surion."KAI's Surion Fly-By-Wire flight control system successfully tested." National Aerospace Laboratory, 7 April 2016.

In 2018, the Defense Acquisition Program Administration (DAPA) certified KUH-1's ice protection system allowing the helicopter to operate in icing condition. The test activities performed include component-level development and qualification icing wind tunnel testing at Cox & Co in Long Island, NY, icing qualification testing of the engine air intake ice protection system at Rail Tec Arsenal (RTA) in Vienna, Austria, artificial icing flight testing using the US Army Helicopter Icing Spray System (HISS), and natural icing flight testing of the complete aircraft while operating out of K.I.Sawyer Airport near Marquette Michigan, USA from October 2015 to January 2016,.

KAI is offering the Surion to international markets for military and civilian purposes. In late 2013, it was reported that KAI had received requests for proposals regarding the Surion from two South American nations and another Asian nation; at the time, KAI stated that the company hoped to sell 60–120 over the following 15–20 years.Waldron, Greg. "KAI eyes export market for Surion." Flightglobal.com, 30 October 2013. International marketing efforts are expected to escalate in 2017, as prior to this point the overwhelming priority had been to fully develop the Surion to conform with existing domestic requirements and roles. KAI has deliberately focused on marketing the type to countries in which previous export success had been found for the KAI T-50 Golden Eagle and KAI KT-1 Woongbi trainer aircraft.

KUH-1 export version prototype helicopter was unveiled at the Seoul ADEX 2019. The new prototype helicopter was developed over four years to meet requirements of foreign customers. This version helicopter is equipped with a GARMIN G5000H avionics suite, and strengthened airframe/structures for the installation of external fuel tanks and a weapons wing pylon. It can accommodate VIPs and passengers with enhanced interior and Bluetooth/wi-fi connectivity.

Design

The KAI KUH-1 Surion is a twin-engine medium-sized multipurpose rotorcraft, carrying up to nine troops, with a crew of four, two pilots and two gunners in the main cabin area, in a utility transport capacity. It has been designed to be rapidly reconfigured to serve different roles. Some models are navalised. The Surion can perform various duties and roles, such as military transport, law enforcement, aerial observation, search and rescue, maritime support, aerial firefighting, and for civilian purposes along with other missions.Donald, David. "Eurosatory 2016: Versatile lifter [ES2016D5]." IHS Jane's 360, 17 June 2016.

Power is provided by a pair of 1900shp class Hanwha Techwin T700-701K turboshaft engines, a licence-built localized development of the General Electric T700. The T700/701K, co-developed by General Electric and Hanwha Techwin, is the first rear-drive variant of the T700 engine and features a -701D common core, high-efficiency counter-rotating power turbine, and a new FADEC system. The exhausts of the engines are equipped with large infrared suppressors. These have been adapted from those used on the AS332. Airbus Helicopters manufactures elements of the Surion's transmission."History: From Eurocopter to Airbus Helicopters." Airbus Helicopters, Retrieved: 22 June 2016. The lower-than-intended level of indigenous production of these components has been a point of controversy.

The Surion is equipped with survivability and damage reduction features. Both the airframe and the cockpit have been made bulletproof against small arms fire. The airframe, tail rotor, and the rotor blades used on both the main and tail rotors are of a crashworthy construction. It has anti-explosion sealed fuel tanks. The main gearbox is capable of flying for a limited period after suffering the loss of lubricating oil. Electronic defensive measures are incorporated onto the Surion, such as a countermeasures dispenser system (CMDS), radar warning receiver (RWR), laser warning receiver (LWR)."KUH-SURION." KAI, Retrieved: 22 June 2016.

British firm Cobham plc provides navigation and communication equipment for the Surion.Waldron, Greg. "Cobham to supply antennas and avionics for KUH." Flight International, 22 December 2010. Sandle Avionic's HeliTAWS multi-hazard avoidance system is installed on Surions in police service.Waldron, Greg. "Sandel Avionics to provide avoidance system for S Korea police's Surions." Flight International, 20 June 2012. Elbit Systems of Israel produces the helmet mounted display (HMD) used on the Surion, the HMD allows the crew to conduct full day-and-night operations.

Operational history