T-50 Triumphs

By Eric Hehs Posted 15 November 2005

KAI Delivers proclaims the caption beneath a large red and blue yin-yang of the Republic of Korea flag. This symbol, the Taeguk, dresses the ramp separating the production facility from the flight test hangars at Korea Aerospace Industries in Sacheon, South Korea. This national symbol and marketing slogan appropriately acclaim the first production T-50 Golden Eagle, which recently rolled off the assembly line at this industrial city near the country's southern coast.

"The T-50 represents a technological and manufacturing achievement for Korea," says Hae Joo Chung, president and chief executive officer of KAI, which hosted the rollout ceremony for the first production T-50 advanced jet trainer at Sacheon in August. "Roh Moo-Hyun, president of Korea, attended the ceremony, which was broadcast throughout Korea as well as to international media outlets around the world," he adds. "The rollout raised awareness of the T-50 within Korea. Our citizens are proud of the aircraft because they realize their country is one of a select few with the ability to design and manufacture supersonic aircraft. That awareness increased further when we exhibited and performed air demonstration routines with the T-50 for the first time at the Seoul Air Show in October."

T-50 familiarity is also building worldwide as the program transitions from test at Sacheon, to production, to operational status. More than 1,200 sorties were completed in the four full-scale development aircraft as of September 2005. The first T-50 aircraft was used to expand the envelope and evaluate stability and control and handling qualities. The second aircraft has been used for air loads and high angle of attack testing. The third aircraft, the first T-50 lead-in fighter trainer, or LIFT version, has been used to evaluate the avionics. The fourth aircraft (another T-50 LIFT version) has been used to test the radar and various weapons and other loadings.

Two ground test aircraft were used for durability, full-scale static, and vibration testing. The Republic of Korea Air Force, or ROKAF, is considering an extension of the flight test program to cover additional weapons testing.

"We met schedules and overcame technical risk during the last two years," explains Enes Park, senior vice president and production director for KAI. "We completed hundreds of test points with our flight test aircraft and signed off on the first production contract with our government. At the same time, we used what we've learned in flight tests to improve the design and made a lot of progress on the shop floor. These changes have been introduced on the production line."

History Of Commitment
The T-50 program represents a significant investment for both Korea and KAI. The total investment in the T-50 program amounts to more than $2 billion. Seventy percent of the funding comes from the Korean government, seventeen percent from KAI, and thirteen percent from Lockheed Martin.

"Our government invested in the T-50 program for many reasons," explains Chung. "Most importantly, government officials wanted full authority over the design and development of the aircraft so that it meets requirements set by our air force. They also wanted to use the program as an industrial tool to give Korea the capabilities needed to design, develop, test, and verify new aircraft. With the T-50, the government has achieved both of its objectives."

Those achievements are viewed as pinnacles by the Korean government and by its aerospace industry, which has progressed from basic efforts to more advanced aerospace accomplishments during the last two decades. These accomplishments can be traced to the late 1970s when Korean Air Lines performed depot-level maintenance on US Air Force aircraft based in the Pacific. Daewoo, Hyundai, and Samsung established similar capabilities soon afterwards. KAL began assembling F-5Es for the ROKAF in the 1980s. During these formative years, Korean manufacturers consistently received high marks for their workmanship and quality. They subsequently won contracts to produce a wide range of components and subassemblies for other aerospace companies, including for Lockheed Martin.

South Korea began developing its first aircraft in 1988. This turboprop trainer, the Daewoo KT-1 Woong-Bee, first flew in 1991, entered service with the ROKAF in 2000, and has accumulated thousands of flying hours since. In the meantime, Samsung, and later KAI, became the prime contractor for the Korean Fighter Program. KFP, as it is known, involved the licensed production of more than 120 F-16s for the ROKAF. The last of these KF-16s rolled off the KAI assembly line at Sacheon in August 2004, and KAI continues to produce F-16 subassemblies at a plant in Changwon.

"Korea has shown its capability to design, develop, produce, manage, and deliver aircraft," reiterates Alex Wanki Jun, T-50 international marketing director for KAI. "Today the pressure is on us to sell the airplane. The T-50 is developed; production versions are rolling off the assembly line; and deliveries to ROKAF begin in December. Now we have to find new customers."

Several factors simplify Jun's marketing challenge. The Golden Eagle has strong selling points, including unique features that give it the ability to bridge the gap between existing trainers and modern fighter aircraft. (The accompanying side story provides more details.) The aircraft is also part of a larger, integrated training system that includes simulators, computer-based training, cockpit and maintenance trainers, and a training management system. These systems can be tailored to the specific needs of any customer.

The advanced age of existing training fleets around the world further increases the appeal of the T-50. With most trainers in operation for thirty or forty years, many air forces facing the prospect of expensive upgrades may instead choose to overhaul the way they train pilots. The T-50, combined with its modern ground-based training systems, can significantly reduce the number of flights and flight hours required to produce a fighter pilot. Improved training and cost savings are the ultimate rewards.

Potential Sales
"We hired a consulting group in 1999 to study the potential for the T-50," Jun notes. "They looked at two markets — advanced jet trainers and light combat — for a thirty-year period and found a worldwide requirement of 3,300 airframes.

"Since the study, purchase decisions by several countries have been delayed because of the lower priority given to the acquisition of new trainers," Jun continues. "This new schedule creates an important timeline from 2008 to 2012 when a lot of airframes around the world will reach their age limits, and air forces will have to replace them with such aircraft as the T-50. Singapore, Greece, Poland, Israel, and several other countries plan to purchase aircraft in that time frame."

Several other factors affect the total number of potential sales. For one, some air forces may not seek to replace their training assets on a one-to-one basis. For another, ground-based training systems have improved so much the last few years that not as many training aircraft are required to perform actual flying.

Three or four training aircraft are competing for the roughly 2,000-aircraft potential that remains after such considerations are factored into the equation. The T-50 is widely recognized as a top contender for many of these sales. It is also the only new supersonic trainer available. Not coincidentally, several countries have expressed interest in the Golden Eagle.

Those potential customers might want to speak to Hui Man Kwon, the first company test pilot for KAI on the T-50 program. Kwon, called He-Man by his colleagues, is one of seven test pilots. Two are KAI pilots; the remaining five are ROKAF pilots. To date, Kwon has accumulated 140 hours in the T-50. He also accumulated more than 1,000 hours in the F-16 as a fighter pilot in the ROKAF, many of those hours spent as an instructor pilot. As a graduate of USAF Test Pilot School at Edwards AFB, California, he flew more than thirty varieties of aircraft.

"My F-16 experience made me very comfortable with my first flight in the T-50," he says. "The cockpit concepts are very similar and both aircraft have exceptional flying qualities. The T-50 behaves very much like an F-16, sometimes even smoother than an F-16 in some flight regimes. Visibility from the rear seat of the T-50 is much better than from the rear seat of an F-16. The stick sensations are also quite different. The T-50 has an active stick, that is, stick movements in one cockpit — front or rear — are transmitted to the stick in the other cockpit. The active stick makes monitoring stick movements of the front cockpit easy for an instructor in the rear cockpit, and vice versa. By comparison, the F-16 stick is fixed with no transferred movement front to rear or vice versa.

"Transitioning from the T-50 to the F-16 will be very easy," continues Kwon. "I'd say the transition could be made with ten or fewer sorties if the student pilot is comfortable in the T-50. However, any pilots transitioning from conventional fighters require at least thirty to forty training sorties to safely fly the F-16. After our air force implements the T-50 into its training system, students should be able to move directly to an F-16 with minimum transition flights."

Off-loading training requirements from operational conversion units in terms of manpower and aircraft usage is yet another advantage of the T-50. As the ROKAF incorporates the T-50 into its force structure, this advantage will become more measurable.

The first T-50 will be delivered to the ROKAF in December. Initial instructor pilot training will start at Sacheon AB soon after. The initial instructor pilots will then move to Kwangju AB where they will generate an initial cadre of instructors. After ten to fifteen instructors are fully trained and qualified, training of the first ROKAF students will begin.

Production Line
A thoroughly modern T-50 production line is geared to support those training plans. "The rollout of the first production aircraft in August was just a start for us," notes Park. "We celebrated; now we get to work. KAI will deliver two aircraft in 2005 and eight aircraft in 2006. After that, KAI will deliver about one aircraft per month."

The Sacheon T-50 production line can impress the most critical industrialist. A wholly digital design provides the basis for a near paperless production process. Work instructions appear on video screens at every workstation. Laser alignment systems help workers mate major assemblies with micrometer precision. On the production line, workers are physically fit and take their jobs very seriously. Teamwork is emphasized and practiced by all up and down the line.

The production line itself is another selling point. Designed for a 1.5-aircraft-per-month production capability with a single shift, the assembly process can produce up to 2.5 aircraft per month by simply adding another shift. "We don't have a problem meeting customer requirements for twelve aircraft in one year," explains Man Sik Park, director of the T-50 management team at Sacheon. "If a new customer signs up for T-50 trainers right now, we could deliver those aircraft in three years. Getting more customers than our line can currently handle is no problem because we can increase the production rate further with additional tools and assembly jigs."

Potential T-50 sales enjoy another important advantage: the luxury of a relatively long production schedule. KAI currently has a firm order from ROKAF for twenty-five aircraft. Additional contracts account for the remaining sixty-nine of the planned production run of ninety-four T-50s. These ROKAF orders will span as many as three Korean budget cycles, to 2012.

"T-50 variants, such as the A-50, will likely extend that schedule," notes Sung Sub Jang, senior vice president and general manager of the research and development division for KAI. "We are also studying more advanced single-seat versions of the aircraft, called the A-50+. The aircraft could replace ROKAF's F-5s and extend the production run for ROKAF aircraft another six years or longer."

"The aircraft has a lot of potential," adds Rich Loman, deputy program director of the T-50 program for Lockheed Martin. "It is a great design with proven systems in addition to a proven engine in the F404. Nothing will stop KAI once the company completes its first international T-50 sale and shows how it can meet commitments."

"Many countries have expressed great interest in the T-50," concludes Chung. "The future of T-50 will be bright, with KAI's partnership with Lockheed Martin an essential part of that future. Our relationship goes back more than twenty years with coproduction and then licensed production of our F-16s, both successful programs. We see our relationship continuing with Lockheed Martin as a major player in the T-50 program. Currently, Lockheed Martin provides technical assistance to our ongoing production program. Later, Lockheed Martin will support our development of future aircraft configurations. Together we will market T-50 sales internationally. Our relationship and our combined efforts ensure a successful program."

Anatomy Of A Golden Eagle
The T-50 looks much like a two-seat F-16 from an overhead perspective. A blended wing/fuselage, single vertical tail, and the general planform shape are similar. With a length of forty-three feet and a wingspan of thirty feet, the T-50 is about four feet shorter than the F-16. The control surfaces and tails are larger relative to the smaller size of the T-50. The extra area improves handling characteristics at lower speeds and makes the aircraft easier to land. Other distinguishing characteristics include a canopy bow that provides additional bird strike protection; a narrower, more streamlined nose that corresponds to smaller radar requirements; and larger landing gear to absorb harder landings.

The most distinctive features of the T-50 are its twin side-mounted inlets that direct air to a single General Electric F404-GE-102 engine. The afterburning engine is a proven, reliable design. The engine incorporates dual-channel full-authority digital electronic control optimized for safety and maintainability. More than 3,700 F404s have been delivered worldwide, accumulating more than 12 million flight hours combined. The engine produces 17,700 pounds of thrust, giving the aircraft an exceptional thrust-to-weight ratio.

The maximum takeoff gross weight is 29,700 pounds; the maximum rate of climb is 39,000 feet per minute; and the maximum speed is Mach 1.5. The service ceiling is 55,000 feet. The design load factor is eight g's; the trainer airframe is designed for up to 10,000-hour service life (8,300 hours for the lead-in fighter trainer version).

The T-50 has an onboard oxygen generating system that simplifies maintenance tasks and reduces the amount of necessary ground equipment.

A triple-redundant electrical system increases safety. Relaxed static stability and fly-by-wire digital flight controls offer superior aerodynamic performance and handling qualities.

Modern cockpit features include hands-on throttle and sidestick mechanization, electronic flight instruments, head-up display, up-front controls, two five- by five-inch color multifunction displays, integrated advanced avionics and sensors, GPS/INS navigation, embedded training features, in-flight recording and post-mission debriefing capability, and a Martin-Baker zero-zero ejection seat. The seatback angle is seventeen degrees — similar to the seat angles of the F-35 Joint Strike Fighter and the F/A-22.

The aircraft is designed for low-speed approach landings. A larger tail, flaperons, and rudder make the T-50 easier to control at lower speeds. In addition, the control surfaces move at faster rates to further improve handling characteristics. By design, the aircraft lands better than most fighters. The angle of approach is lower than that of an F-16 so the pilot has a better forward view on landing. The raised aft seat gives instructor pilots a much better view in front of the airplane as well. The flight control side-sticks in the front and rear seats move together so that instructor pilots can feel student pilot inputs. The aircraft is designed to display the performance needed to support lead-in fighter training missions. This LIFT version of the aircraft features an APG-67 multimode fire control radar, a modified M61 three-barrel 20 mm internal gun, a weapons management system, and seven hardpoints for carrying up to 9,500 pounds of a variety of air-to-air and air-to-ground weapons. (The standard T-50 has no radar or internal gun.)

Eric Hehs is the editor of Code One.