FLIGHT TESTING THE GRIPEN - MORE THAN JUST AN AIRCRAFT! (Cont)
FLYING THE WOLF IN SHEEP'S CLOTHING
After all this discussion about how good the systems are, as a pilot, you really have to get down to the basic question - does it fly well? The simple answer is yes - very well! To get to that stage I had to jump through all of the hoops, as with any air force, particularly when you are going to fly their new baby!
First Things First (back to top)
The first part of my preparation involved getting a good briefing on the aircraft and its systems, as well as its support structure and general operating philosophy. At this point my pilot, Lt Col Björn Johansson (Test Pilot at the Swedish Air Force's test centre in Linköping), briefed me on the 'bits' they wanted me to see and said that I would have about 20 minutes free time to 'explore' the aircraft. He also explained that a second Gripen would fly with us to act as a target, to pass data link information and to be used to look at close formation - quite a package was in store. Next it was time to get in to the Multi-Mission trainer. This was an excellent systems trainer and allowed time to 'play' with all the switches, so that time was not wasted airborne fumbling in the cockpit. It also gave a first look at the screens to become familiar with the information they displayed and the different types of symbology.
Next came flying clothing fitting. This was again some novel equipment that I had not come across operationally before. The Gripen is a nine-g capable aircraft; this is similar to other aircraft in service today. However, because of the onset rate (6 g/second) and the carefree handling, the Swede's are very worried about G-Lock. This is when so much 'g' is pulled so quickly that the normal, early characteristics of high 'g' (tunnel vision, and tingling sensation), are not there for long enough to warn the pilot of an impending 'blackout'. To try and overcome this the Gripen flying clothing includes: an all over g-suit, which completely covers your legs; a g-jacket that inflates in a similar fashion to the leg g-suit; and pressure breathing, which acts against the jacket and feeds you air under pressure. The combination of the last two items aims at increasing your stamina for pulling high 'g' because it helps you to breathe without having to use your diaphragm muscles under high loads. This part of the flying clothing worked really well in the air. It is claimed that the additional protection that all this equipment gives a pilot against the effects of pulling high 'g', is an effective reduction of three-four 'g'. This means that when you are pulling nine 'g' your body thinks it's pulling five! This capability does come with a cost - about 120,000 Swedish Crowns all in (£8,800)!
No visit to a flying centre is ever complete until you have visited the doctor for the customary cough with your trousers down - what are they checking there? Still with that ritual over I was pronounced fit to fly and it was off to the aircraft for some cockpit familiarization time. This time is invaluable as it gives you the chance to sit in the cramped cockpit, with your kit on, and still try to locate all the switches. It was also a good time for Björn to give me a safety briefing and to discuss ejector seat capabilities should the unthinkable happen. The final job for the first day was to check the weather - it looked good, so I could retire to the Officers' Club happy. Unfortunately, Swedish 'Met' men are no different from any others - when I got up in the morning the cloud was on the deck and it was raining! Now there's a surprise.
Time to Fly (back to top)
Thankfully, all was not lost, Björn had checked the forecast, and it was going to improve in the afternoon, at least the cloud would lift sufficiently to get airborne and it would be 'workable' on top of the clouds. Just after lunch the improvement had arrived (400 feet broken cloud and 3 kilometres visibility in rain) and it was time for the off.
Getting into the cockpit was straight forward, and strapping in to the Martin Baker Mk10S seat was simple. With all the flying clothing on the cockpit was now tight, but comfortable. The starting procedure was very simple and it was possible to get started and be ready to taxy within three minutes. Indeed, the limiting factor was waiting for the 'ring laser gyro' inertial navigation system to align. Taxying was a little sensitive to start with as only small rudder pedal movements were required. Pre-take-off checks are extremely simple as most things are automatic (including flaps).
The take-off technique was to apply full dry power against the brakes, then to release brakes at the same time as selecting the afterburner. Acceleration down the runway was good (aircraft configuration was an empty centre-line fuel tank, and internal full fuel) with a time to airborne of 18 seconds and 330 kilometres per hour (kph) (180 knots). The rotate speed was 240 kph (130 knots). Climb speed I was told was any speed! Pulling the nose back to climb at 550 kph (300 knots) produced an impressive climb rate.
There is no vertical speed indicator in the jet, which was slightly alien to me, but the rationale was that with a good 'velocity vector' telling you exactly where your aircraft is going in space, it's not needed. Indeed, display reduction where possible was a theme to the aircraft's cockpit displays. There was no easy way to obtain hydraulic pressures or engine secondary parameters, all were considered redundant using modern monitoring systems. I perhaps tend to agree with this approach - but it takes some getting used to. One aspect of the cockpit that I did not like (probably because it was different) was the altimeter. Apart from being in metres and not feet, the 'zero' was at the bottom of the instrument rather than at the top! Don't ask why, a bit like Russian artificial horizons, it's just their way. However, they did say that export versions would have the altimeter with the 'zero' at the top as well as having English (instead of Swedish) labelling and being in knots and feet. (All that would have helped me tremendously, particularly in the first ten minutes!)
System Heaven (back to top)
Once through the cloud I had my first chance to properly look at the systems. The first thing was to select attitude and height hold. This was a poor man's autopilot but worked well and again had some good features. These included holding a bank angle or a pitch attitude, as well as being able to change heading using the rudders only. The aircraft was also fitted with an auto-throttle, which held the speed at the time of selection (gear up). When the gear was down the auto-throttle would fly either 12 degrees angle of attack (AoA), for normal landings, or 14 AoA for short field landings.
Then it was time to play with the clever stuff. First, the second aircraft data-linked some target information on to our tactical display. We were then able to carry out an attack using this information. The ground controller was also sending tactical information and other targets to attack. The information flow was impressive and the feeling of extended knowledge was tremendous. Using the information from the ground controllers we were able to plan and execute our own intercept on the second aircraft. This got us into a position where we could use some of the radar auto-detect and lock-on modes (in generic form, and only some modes as most are secret). The radar was very easy to use and mostly automatic, following the philosophy of 'make it simple'. It did not really seem to matter whether we were attacking an airborne or ground target, the attack symbology was the same, with the same firing cues and format. The design aim behind this similarity was the multi/swing role capability. For me, during my short exposure, it seemed to be within the pilot's workload capability to operate in this very flexible way.
During the intercepts I had a chance to manuvre the aircraft aggressively. Using the carefree handling qualities of the aircraft, you really could 'pull' and 'point' it where you wanted, this is when all the extra 'g' protection from the flying clothing came into its own. Similarly, the ventilated 'emersion' suit (to keep you dry should you eject in to water) was excellent, and even with aggressive manuvring kept you cool. High-g loops were easy to fly with the computers taking care of the aircraft. There were some very helpful symbols on the airspeed indicator that increased situational awareness during combat manuvring: one was a 'horseshoe' symbol that indicated the best 'corner' or turning speed, and the second, was an 'x' which indicated the speed of the aircraft that was being tracked by the radar. Both features were good examples of the thought that had gone into helping the pilot with his combat tasks.
At all times, including during formation flying, the aircraft response was excellent and very predictable, with no feeling of sensitivity in the controls. In the 'free' time at the end of the mission I performed some test pilot manuvres to confirm for my self what the control system characteristics were like. I excited the longitudinal short period mode (characterized by a high frequency pitch nodding motion) of the aircraft and it damped almost immediately, the dutch roll (a 'wallowing' motion caused by the interaction between lateral and directional stability) was similarly damped; normal aileron rolls were very predictable, with a roll rate of approximately 250 degrees per second. For the configuration that I flew I could not fault the control system - much work had been done on it since the early development aircraft losses, which were attributed to sensitivities in the digital flight control system.
TIME TO WAKE UP (back to top)
We were having so much fun exploring the Gripen's capabilities that I was not checking the fuel. Luckily, the aircraft (and Björn) did and it informed me that we were down to 40 percent remaining, which, with the poor weather, meant it was time to head home. This is another feature of Swedish aircraft development that is different: the fuel gauges are in 'percent' not pounds, litres or kilograms! This made life very simple: when fully loaded with internal fuel you had 100 percent, at 40 percent you were given a 'heads-up' or 'bingo' cockpit warning, at the 24-percent warning you started home and you landed by 15 percent - simple. If you had fuel in the external centre-line tank this was just added to the total, ie the gauges read 140 percent.
Because of the weather I had the chance to fly a tactical ILS (TILS), which is similar to an ILS but the ground equipment comprises only one unit (instead of one for localizer and one for glideslope as in a standard ILS), and this is mobile. The system is ideal for the dispersed operations that the Swedish Air Force perform - here they take their aircraft and send them in to the countryside to operate off road sites. At the same time they would take all their mobile command and control systems with them. This capability was very similar to Harrier 'field' operations and afforded their Air Force great flexibility. The TILS would have been a 'god send' during my Harrier field operations, particularly when the weather was bad - which it always seemed to be when we deployed the jets! As an aside when the Gripen is deployed to its road sites it uses an 800-metre strip (2600 feet), which is remarkably short for a conventional aircraft. Indeed, I had a chance to try this in the simulator and the stopping distance from a 14 AoA approach was 350-400 metre. Even in a Spitfire you would think twice about operating off those distances!
Normal speed in the circuit was 550 kph (300 knots) reducing to 280-300 kph (155 knots) on finals, with a touchdown speed of approximately 270 kph (145 knots) for a 12 AoA landing and 235 kph (130 knots) for a 14 AoA landing. There are no real checks to do apart from putting the undercarriage down, as everything else is automatic (including the flaps when the wheels are lowered, and slats depending upon AoA). Throughout the approach the flying qualities were impeccable making it very easy to fly. The fun started when you touched the ground. Because of the braking logic you can apply full brakes while still airborne, the system will then brake after the nose-wheel touches the ground (I was very nervous of doing this!). An unusual feature of the braking system was that the nosewheel also had a brake fitted. However, the really interesting bit was the way all the control surfaces, including the canards, immediately went to their maximum drag position on touchdown. This alone produced tremendous deceleration at the higher speeds. My overall impression of the flight (apart from that it was too short) was that it really had shown me the NEXT generation of multi-role, swing-role combat aircraft.
. . . AND THE FUTURE? (back to top)
While much of this aircraft was very futuristic there are still some bits missing. The majority of these have been around for a long time and just have not been fitted yet. For example, the aircraft did not have a full night capability like, say, the Harrier GR7 (Forward Looking Infra Red (FLIR), or Night Vision Goggles). However, these were being flown at the test centre. Protection for the pilot against Chemical and Biological warfare had not yet been fully implemented, but this was coming soon. Björn said that they were considering many improvements over the next year or two, including the addition of a GPS and a voice activation system. A good feature soon to finish its development was a departure protection mode, which would work within the control system and be fully automatic. I had the chance to test the capability in the simulator and it was very effective at protecting the pilot during recoveries from unusual positions. This protection was designed as a 'what if' protection because the aircraft had been demonstrated to be departure and spin resistant without severe control system degradation. An extension of the departure protection mode is a Ground Collision Avoidance System (GCAS), which is being jointly developed with the Americans. At present the aircraft only has a ground collision warning system.
Other new features to come include even larger, colour screens (6 by 8 inches, 15 by 20 centimetres). These were much better and made it easier to take a quick look at the screens to glean the information. Along with the new screens comes a more comprehensive up-front controller to replace the Mode Selector Panel. This will be similar to the Harrier or F18 up-front controller and will allow selection of radio frequencies, transponder squawks and other data changes that previously had to be done looking deeper into the cockpit. Air-to-Air refuelling is also coming, but Björn explained that this had never been a requirement for the Swedish Air Force, which is more oriented towards defence of its homeland and therefore a long range capability was not important. He explained that if extra fuel in combat was needed there was always somewhere close to land and, that as the aircraft was capable of 'hot' refuelling (with engine running), it was not a limiting factor.
During the simulator time I also had the chance to try out the new helmet mounted display. This projected height, speed and a weapons 'designating' cross (for Air-to-Air and Air-to-Ground targeting) on to the inside of the helmet visor. The display was similar to other helmet mounted displays I had seen and was another workload reduction device. During simulated combat it was so much easier to just 'look' at an opponent to get a missile lock rather than having to turn the whole aircraft at him to get a firing solution.
The majority of the improvements are scheduled to be in the Export Version/Batch Three aircraft, with a predicted time-scale of about 18 months, starting at aircraft Serial Number 207.
A TRULY MULTI-CAPABLE SYSTEM (back to top)
Without doubt the Gripen was very capable in the Air-to-Air role, but my visit had also demonstrated that with the right aircraft and cockpit design it was possible for a single-seat aircraft to be truly multi-role. The Gripen weapons system had all the elements in place to warrant 4th Generation status. The aircraft was very simple to operate, had carefree handling and performance, but more importantly it had a great cockpit containing tools to reduce pilot workload and to help in the decision making process. The data-link technology in the aircraft was outstanding and demonstrated the Swedish mentality well: to be a winner in the modern combat environment a weapons system must be technologically advanced, it must be highly mobile but above all else it must win the information war - 'information superiority' is the key to success. Having seen their aircraft and support systems in action you cannot help agreeing!
I would like to thank all those that made the visit possible but in particular Lasse Jansson, Björn Johansson and AFM in the UK for sponsoring the visit.
GRIPEN SPECIFICATION (back to top)
First Flight of Prototype - 9 December 1988 (flown by Stig Holmström)
First Two-seater Flight - 29 April 1996
Wingspan - 8.4 m (27 ft 6 in)
Length (single seat/two seat) - 14.1 m (46 ft 3 in)/14.8 m (48 ft 6 in)
Height - 4.5 m (14 ft 9 in)
Max Take-off Weight - 14,000 kg
Max Speed - High Level 1.8-2.0 Mach
Low Level - 1.15 Mach
Level Acceleration (low level) - Approximately 30 seconds from Mach 0.5 to Mach 1.1
Turn Performance - Sustained 20 degrees/second, Instantaneous 30 degrees/second
Maximum Load Factor - 9 g sustained
Climb Performance - Less than 2 minutes from brakes release to 10 km (33,000 ft)
Radar - Ericsson PS-05/A, multi-mode, pulse-Doppler
Engine - Volvo Aero Corporation RM12 turbofan (GE F404J)
Thrust - Dry Power - 12,000 pounds (53.4 kN)
Afterburner - 18,100 pounds (80.5 kN)
Fuel (internal) - 3,000 litres
WEAPONS CARRIED (back to top)
Internal 27 mm Mauser BK 27 high-speed cannon (1,700 round per minute) (not fitted to two-seater)
Sidewinder AIM-9L IR-homing air-to-air missile
AIM-120 AMRAAM active radar-homing air-to-air missile
AGM-65 Maverick IR-homing air-to-surface missile
Rb15F radar-homing air-to-ship missile
Pods containing six 13.5 centimetre air-to-surface rockets
BK39/DWS area weapons
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