[SIZE="4"][*******"DimGray"]GRIPEN PILOT REPORT [/COLOR][/SIZE]
Gripen Key to Sweden's Air Defense Force Quick turnaround time, improved information warfare capability give Saab fighter an edge against larger foes.
DAVID M. NORTH
[*******"Red"]6 December 1999[/COLOR]
[SIZE="4"][*******"dimgray"]Aviation Week & Space Technology [/COLOR][/SIZE]
Vol. 151, No. 23
© 1999 McGraw-Hill, Inc.
Sweden is constructing one of the most effective air defense structures in the world using its air force's Saab Gripen multirole fighter, Saab/Ericsson Erieye airborne early warning platform, tactical information data link, and a modern command and control system.
While the Swedish air force has had its tactical information data link system in operation since the mid-1980s, it is the replacement of the Saab Viggen with the Gripen and the addition of the Ericsson-developed early-warning system on a Saab 340B that has addressed modern information warfare and made the service a fourth-generation operational force. While the cost of the air national defense system is a large part of Sweden's military budget, it does not bear the high total cost of similar systems either being evaluated or installed by other countries.
I was fortunate to be invited to visit the F7 Wing at Satenas in late October to fly the Gripen. The air base had been chosen to be the primary training base for Draken and Viggen pilots transitioning to the Gripen. There are two JAS 39 training squadrons here, and the first 16 Draken pilots from the F10 Wing are undergoing training to be the nucleus of the first operational Gripen squadron at Angelholm. However, both JAS 39 training squadrons are considered to be combat operational by the air force.
The training facility here is housed in a ``Y''-shaped building adjacent to the Gripen ramp and hangars. It is specifically designed for training operations, with two full-mission simulators, four multimission simulators and numerous study rooms in one wing. The squadron offices and flight operations are contained in another wing, while associated units and the ground mobile command and control units are in the remaining wing. The facility is one of the best of its kind I have seen in military operations.
Transitioning pilots will receive 5-6 months of training in the Gripen here and then return to their respective squadrons for a year of advanced tactical training. New pilots joining the F7 Wing after a year of primary flight training and some 240 flight hours will train for one year in F7, receiving 40 hr. in the simulator and 62 hr. in the Gripen prior to going to a squadron for more advanced tactical training. The first group of these new pilots is expected at Satenas late next year.
Prior to the flight, I had to be fitted for an exposure or ``****y suit'' as well as lower and jacket g-suits, all designed by the Swedish air force for its own operations. Because of the cold water temperatures in and around Sweden, an exposure suit is worn most months. The suit, once donned, is quite comfortable.
I was also able to sit in one of the four multimission trainers (MMT) for 30 min. to get acquainted with the Gripen cockpit. The cockpit briefing was given by Lt. Col. Bjorn Johansson, an air force test pilot attached to the Swedish Defense Material Administration (FMV). I was to fly with him the following day in the Gripen.
The Loral MMT is equipped with a Evans & Sutherland three-screen vision display, a head-up display (HUD) and the Gripen cockpit. The MMT can be linked with the dome simulators and other MMTs to show scenarios involving four aircraft. The cockpit is designed with three multifunction displays in a ``Y''or left, right and lower display arrangement, much like the Boeing F/A-18 series of multirole aircraft. An upfront controller is below the HUD, but a good adaptation of the hands-on-throttle-and-stick (HOTAS) concept eliminates having to reach up and use the up-front controller.
The left multifunction display (MFD) is used for flight data, including the HUD and defensive aids and sensor images that might be shown on the HUD. The right MFD is used to show the image from the Ericsson PS-05/A radar, as well as other images from a Flir or reconnaissance pod. Neither of these two capabilities are under contract for the Gripen at this time. The lower MFD contains the tactical picture shown on the horizontal situation display format.
MMT time was very valuable, and I had difficulty differentiating all of the functions of the radar, target acquisition, speed control and different map scales controlled from the throttle and throttle guard as my time ran out. While Saab has investigated voice activation of many of these functions, it is not a high priority program for the Swedish air force. The use of a trigger guard and a single trigger on the control stick to launch air-to-air and air-to-ground weapons was much easier to absorb in my training.
I also had a problem distinguishing the symbols shown on the radar and tactical displays for targets, threats and wingmen. This was related to my recent lack of practice in evaluating tactical air-to-air situations as well as the monochromatic display.
Symbols for wingmen are shown with ``tails,'' the number of tails representing the wingman's number. Their altitude is shown behind the symbol, and threats are shown as designated by the pilot, the wingman or ground control. I also found it hard to get accustomed to the symbology that designates target priorities. My slowness in comprehending all that was happening in the tactical area could be overcome, I learned, with more simulator time.
To further help the pilot's situational awareness, Ericsson has developed larger, color 6.2 X 8.2-in. displays to replace the smaller monochromatic ones in the existing Gripens. The newer displays should be available in the third batch of Gripens to be delivered beginning in the 2001-02 time frame. The day after my Gripen flight, I flew in a dome simulator at Saab's Linkoping facility. The simulator had the new displays, and I found that my ability to comprehend what was occurring in the tactical displays was greatly increased.
Doing the walkaround while the fighter was in the hanger gave me the opportunity to observe just how small the single-seat Gripen really is. If you take a Lockheed F-16C and reduce its wingspan by some 3.5 ft., length by 3 ft. and height by almost 2 ft., you have the JAS 39A. The Gripen's empty gross weight of 14,600 lb. is some 4,000 lb. lighter than the F-16C.
Seeing the Gripen with its access panels open also underlined the compact design of its interior. Because of the dense interior, I was surprised when Saab test pilot Magnus Ljungberg explained that the inflight refueling probe for the export version of the aircraft fits over the right engine intake without changing the aircraft's fuselage. This is one of the modifications being developed with BAe Systems for the export version of the Gripen. The extended probe is located approximately 90 deg. to the pilot, and Ljungberg said that refueling was quite easy.
There was clear access to maintenance panels from the hangar floor. The Gripen was designed by Saab to be repaired easily and quickly, with a low life cycle cost.
The Swedish concept of using dispersed bases for flying operations puts a unique demand on maintenance and reliability. The Gripen is equipped with a maintenance fault localization and diagnostic system that helps speed repair work. The bases often consist of a road with a turnaround area and some shelter under trees. The crew required to handle a Gripen at one of these dispersed bases is one officer and seven conscripts. F7 pilots claim that the ground crew is able to refuel and rearm the Gripen in less than 10 min. for an air-to-air mission and less than 20 min. for an air-to-ground mission.
With more than 14,000 missions flown in the Gripen, the air force is finding that the new aircraft is requiring at least 40% less maintenance man-hours and 50% of the fuel usage of the Viggen.
The following morning, the day of the scheduled flight, there was a low overcast, fog and rain and the only suitable alternate was to the far north. So we we did as many pilots had done before us--sat and drank coffee, discussed previous flying operations and waited for the weather to get better. By noon, the conditions had improved--the visibility had increased, and there were suitable alternates, although the overcast was still well below 500 ft.
Johansson and I walked to JAS 39B No. 802 in front of the training facility, while a second flight crew manned another JAS 39B. The two-seat aircraft are owned by FMV (F7 is not scheduled to receive a two-seater until late next year).
The first impression on reaching the two aircraft being prepared to fly was the noise level of the auxiliary power units. Saab is replacing the Gripen's Microturbo units with quieter Sundstrand APUs during the next year.
I took the rear seat while Johansson occupied the front seat. The two-seat Gripen is 2.2 ft. longer than the single-seat version, and the internal gun has been removed. Fuel capacity is the same for both aircraft. Unlike the Dassault Rafale, there is no HUD in the back seat, although HUD and video information can be depicted on the flight data display. I found that once strapped into the Martin-Baker ejection seat, with leg and arm restraints attached, the cockpit was very comfortable. The functions I needed to operate on either side panel were easily accessible. The recline angle of the seat is less than that of a F-16, but more than that of the Viggen and the Boeing Hornet.
THE SWEDISH APPROACH to fuel capacity and fuel usage is quite simple--when the internal fuel capacity is full, the gauge registers as 100% in the cockpit. There is no fuel quantity in kilograms or pounds, nor is there a fuel flow meter. Internal fuel is approximately 5,000 lb., and when a full center drop tank is flown, it shows 140%. Fuel bingo also is shown in percentage remaining. While we were carrying a center drop tank, there was no fuel in the tank. Ramp weight of the JAS 39B was close to 24,000 lb.
JOHANSSON STARTED the single Volvo Aero RM12 turbofan engine, and following a short after start and system check, we taxied to the active runway. He deactivated some of the radar modes and the defensive electronic countermeasure systems which were deemed to be sensitive. He also demonstrated the agility of the aircraft on the ground by using the nosewheel steering to make several 360-deg. turns. This capability is especially necessary when operating from dispersed bases.
Johansson advanced power and acceleration was especially brisk in afterburner, with a takeoff roll of close to 1,700 ft. (518 meters) Once the landing gear was raised, the close-coupled canard-delta configured aircraft was clean with no other inputs needed. We entered the overcast at about 400 ft. and came out in the clear about 8,000 ft. The single-seat Gripen has the ability to climb to 33,000 ft. in less than 2 min.
Once leveled near 20,000 ft., Johansson gave me control of the aircraft. He then proceeded to demonstrate many of the features of the Gripen in the air-to-air role and the air-to-ground roles. One of the most impressive features of the aircraft is the ability to remain in a passive radar mode while targets are fed to the aircraft by data link from either a wingman or a ground controller. A ground controller in our area designated our wingman some 30 naut. mi. away as a target, and his altitude appeared behind the target symbol. While still passive, we choose the Raytheon Amraam for launch and fired the simulated missile for a hit.
The Gripen is currently capable of carrying four Amraams on the underwing stations, and a center fuselage station launcher is under study that would be capable of carrying two more Amraams. Full integration of the radar missile into air force operations was accomplished in April.
Early warning and battle management for the Swedish military has been further enhanced by the introduction of the Ericsson Erieye early-warning system mounted in a Saab 340B turboprop. The active phased array pulse Doppler radar offers an increased range of land-based radar out to 450 km. (243 naut. mi.), and a detection range for small fighter type aircraft of close to 350 km. (189 naut. mi). The Erieye uses S-band radar for a sharp and narrow main beam with low sidelobes. This configuration also is more resistant to jamming. The Swedish air force has four Erieye in operation, while two will be loaned to the Greek air force for several years prior to their receiving similar Ericsson Erieye systems mounted on Embraer 145s. The Swedish air force will eventually operate a total of six Erieye aircraft in two operational squadrons.
Johansson then identified a ground target that showed up on our multisensor display, that had been designated by our wingman and data-linked to us. Additional information from our wingman, included his fuel state, weapons available, targets selected and the view through his HUD, all appeared on the multisensor display. We selected a simulated RBS-15 antiship missile and launched it some 30 naut. mi. away from the ship in a harbor on Lake Vanern near Satenas.
THE PS-05/A RADAR was turned on and the antenna removed from its near horizontal park position. In the air-to-ground mode, the resolution mapping of the lake was quite good, but it had the capability to be better. The radar has ground/sea moving target indication and tracking, as well as air-to-ground ranging. In the air-to-air mode, the Gripen's radar has an all-altitude look-down capability and can track up to 10 targets. Its track-while-search feature in the automatic mode assures good situational awareness, and the mission computer predicts the greatest threat to the aircraft.
Ericsson is looking to the U.S. and France to help in the development of an active electronically scanning antenna for the Gripen. A contract for joint development is planned for next June with the intent of having a demonstration of the new radar in 3-4 years.
With the radar still in the air-to-air mode, we picked out our wingman/target at near our 10 o'clock position and switched to the heat-seeking missile mode. While we did not receive a tone, the wingman was well within the range of the Sidewinder-type missile. The range circle around the pipper showed maximum, no escape and minimum range of the missile's envelope, although I still could not see our wingman. Johansson attempted to point out our wingman passing across our nose and moving to the one o'clock position. A helmet-mounted sighting system is in development for the Gripen, and a prototype is being flown at Saab in its dome simulator.
Another virtue of the Gripen is its small size, a not-to-be-underestimated positive factor when it comes to within visual range combat. I had difficulty picking the wingman out over the overcast until he reached our two o'clock position low. I rolled in on the wingman, and switching to guns, saw the symbol on the gunsight indicating hits on the other Gripen. While Johansson had to coach me through the switching of radar displays and weapon selection, I realized Saab and the Swedish air force have achieved a low pilot workload for the combat scenario. Compared with other multirole aircraft I have flown recently, the situational awareness and workload in the Gripen appeared to have the edge for intuitive movements and simplicity.
A session in the planning and analysis room after the flight showed all of the parameters of our flight from a digital recorder. The tape verified our missile and gun hits, as well as indicated generic maximum and no-escape ranges. The tape records all button or switch activations as well as flight parameters, weapon delivery envelope and results, and ongoing tactical situation. Four aircraft can be flown together in the evaluation scenario.
I DID NOT MAKE a very good rendezvous with the wingman, missing our closing rate by a large factor, even though his speed was shown on my airspeed indicator. The airspeed is shown in km./hr. and the altitude in meters. While the conversion was my problem, not the Swedes, I had some difficulty in adjusting to the layout of the altimeter, where an even 1,000-ft., (or even-meter) altitude is not shown by a needle arm at the 12 o'clock position, as it is on a regular altimeter.
Flying formation on the wingman was quite simple. This is when I realized that the triple digital flight control system in the Gripen made flying easy. The position of the throttle and the stick mounted on a pedestal below the instrument panel were very comfortable to operate, making another point for good machine-man interface.
The Gripen's stick is designed for movement, some 9 deg. forward, 13 deg. aft and 7 deg. left and right.
Stick movement became more of a factor later when I did a full-throw aileron roll at Mach 0.79. Roll rate was on the order of 240-deg./sec, Johansson said. The altitude was near 15,000 ft. at the time. An initial 6g pullup to a loop was done at 450 kt., and I came out at 10 deg. off heading. A 6.5g turning pull in military power showed the excellent turning capability of the Gripen. Sustained turn performance of the 9g aircraft is given at 20-deg./sec. As Johansson said, the delta wing Viggen seemed to push the air around in a turn, while the Gripen cuts through the air almost effortlessly. The aircraft also provides a very steady gun platform, which I learned as I flew some steep gun attacks against the top of clouds.
The clean lines of the Gripen were apparent as Johansson and I had to keep track of my power setting and speed so as not to break Mach 1.0. The Gripen will do Mach 1.05 at low level in military power.
(*) Advertised maximum speeds for the Gripen are Mach 1.2 at low level and close to Mach 2 at high altitude. Maximum aerodynamic speed of the Gripen has been calculated to be 1,400 kph. or 755 kt.
(* Mil Power = No afterburner)
Johansson said that there have been no problems with the Volvo RM12 engine in the Gripen development or during its some 14,000 missions. The RM12 is a cooperative engine program with General Electric based on the F404 engine in the Boeing F/A-18 Hornet.
The Gripen has been taken to a deep stall, where power was moved continuously between flight idle and military power without any stall stagnation problems. The engine also has operated well at 160-deg. angle of attack and 90 deg. of slideslip, Johansson said.
Volvo redesigned the fan in the F404 engine to give a 10% increase in airflow, with a 6% increase in thrust while increasing the turbine temperature slightly for the RM12 design. The front frame of the engine also was modified to better withstand bird strikes. Volvo also is working on a new full-authority digital engine control (FADEC) and a redesigned afterburner flame holder for the RM12 engine. The 18,400 lb. of thrust in afterburner gives the aircraft excellent acceleration characteristics, and Saab says the Gripen will go from Mach 0.5 to Mach 1.1 in approximately 30 sec. at low altitude.
Similar to other aircraft of like design, such as the French Rafale, test pilots have found that the Gripen is spin-resistant. The aircraft has been put in spins during testing, but some of the control laws and the spin recovery mode in the flight control system had to be modified. The spin recovery mode in the Gripen first stops roll oscillation, then yaw, before pitching the nose of the aircraft down.
By this time, the fuel remaining in the Gripen was reading 40%, and Johansson indicated the steering cue on my HUD display that would get me back to Satenas. A descent was made in the clouds to 800 meters (2,624 ft.) at 500 kph. (270 kt.). The Swedish air force uses a tactical landing system, similar to that of the U.S. Navy, with a slight offset from the runway, Johansson said. At 600 meters (1,970 ft.) and 450 kph. (243 kt.), the autothrottle was engaged by depressing a button on the throttle. The symbology for the approach was easy to follow, although I found myself looking for a rate of descent indication. There is not one installed in the Gripen, because the pilots believed it was not needed.
The aircraft was very steady on the approach and aircraft response matched control input at the lower speeds. Once we broke out below the overcast at some 100 meters (328 ft.), Johansson took the aircraft and landed at near 130 kt. with a angle of attack near 13 deg. for the final approach.
All three landing gear have carbon brakes installed and an antiskid system. On landing, the leading edge of the canard goes down and the elevons go up and the fuselage mounted speedbrakes extend. Stopping distance was about 600 meters (1,970 ft.), although Johansson did not apply maximum braking.
WHILE NOT ABLE TO MAKE the landing in the Gripen, I did land on a road in the high-fidelity Gripen dome simulator at Saab, and found the landing characteristics exactly as I had observed at Satenas. The aircraft was stable on approach, and landing without flare at 130 kt., the Gripen was easily stopped within 600 meters. All in all, I had flown approximately one hour in the Gripen from blocks to blocks. This is a fairly standard flight with internal fuel and more than ample reserves, Johansson said.
There are a number of upgrades and new equipment planned for the Gripen. After flying the aircraft with its smaller monochromatic displays, the larger color Ericsson displays, as flown in the dome simulator, will make a big difference to improve the pilot's situational awareness. An OBOGS on-board oxygen generating system will replace the traditional oxygen system in later aircraft. A new inertial navigation system with GPS also is under development. An integrated infrared search and track system is being developed for the Gripen by Saab Dynamics, and it appears that an advanced electronically scanned array (AESA) radar will eventually replace the Ericsson PS-05A radar.
While I was not able to fly the Gripen for a low level flight, my impression is that it would behave quite well at 450 kt. at 200 ft. A digital terrain following feature, such as flown in the Rafale earlier this year, is under discussion for the Gripen, especially if required by an export customer.
Any multirole fighter/attack aircraft is a compromise these days, and the Gripen is no exception. When developing the Gripen, the Swedish air force, FMV and Saab opted for a small aircraft, with good performance and with emphasis on excellent warfare information capabilities. After flying the Gripen aircraft and simulator, and observing the Swedish air force operational philosophy and capabilities, I believe the Swedes hit the mark.
The Gripen is about half the weight of the Boeing Super Hornet I flew last year and the Dassault Rafale flown earlier this year (AW&ST Aug. 31, 1998, p. 50; July 5, p. 48). It also is considerably lighter than the Eurofighter. With this lighter weight comes a less expensive airframe, with the Gripen coming in at close to half the flyaway price of the Super Hornet, Rafale and Eurofighter. The lighter weight also means less payload capability. But, with the Gripen's current payload, the reliance on smart weapons and the quick-turnaround capability from dispersed bases, a high payload requirement is not as important.
While high performance was not the Swedes' highest priority in its compromise package, the balance between the aircraft's speed, acceleration, turning rate and overall maneuvering capability makes the Gripen an excellent multirole combat aircraft. While not a stealthy aircraft, or in the same league as the Lockheed Martin-Boeing F-22 Raptor, its small size and design does give it advantages against larger foes.
Where the Gripen has the current advantage over many of its competitors is its information warfare capability and pilot's situational awareness. The aircraft's secure tactical data link system is the key to the pilot's ability to understand and exploit the tactical combat situation. This system also allows one aircraft to be the radar emitter, while transmitting all of the necessary target data to four passive aircraft spread out for tactical advantage. That same tactical information can come from ground control or from the Swedish air force Erieye early-warning aircraft. The low workload coefficient built into the Gripen also allows the pilot improved situational awareness when it is most needed.
The downsizing of the Swedish air force has been one of the driving forces to not only develop an efficient multirole aircraft, but also one that is reliable and maintainable. The Gripen will eventually replace the Viggen flown in the separate fighter, attack and reconnaissance roles. In the late 1980s, the Swedish air force had 425 combat aircraft in some 26 squadrons. By 2007, the 204 Gripens on order will have been delivered, and there are plans to have them operational with eight squadrons, although the basing and potential further base closures is still under discussion in the Swedish Parliament.
FROM MY TIME WITH the Swedish air force, both this recent visit and flying the Viggen with the F13 Wing some time ago from the closed Norkkping base, it would appear that the service is successfully trading in quantity of aircraft for the quality of tactical air operations offered by the Gripen, Erieye and the Swedish military command and control system.
During dinner following the flight, Maj. Gen. Jan Jonsson, inspector general of the Swedish air force, said that he was hoping the service would expand its international scope and participate in NATO-type peace-keeping operations. I have to believe that any tactical operational theatre commander would welcome a squadron of Gripens on the ramp