600 Knots at 200 Feet

The large and slightly ungainly nose has provided a wide, roomy cockpit. After the cockpits of the BAC Lightning and British/French Jaguar fighters, this one looks like a ballroom. The size of the nose radome itself was dictated by the dimensions and layout of the two antennas for the ground mapper and the terrain following radars, the first of which the navigator is checking now with its built-in test equipment. Cockpit layout in the front is pretty conventional, dominated by the big five inch lens head up display (HUD) and the head down repeater projected map display in the centre. The ‘E’ scope high up on the left front panel gives raw from the terrain following radar, and the hand controller – a small handle just behind the throttles with various switches- enables the pilot to control some of the HUD attack symbology and provides inputs to the aircraft’s main computer.

The rear cockpit represents a much greater change from convention. The same roomy cockpit space has allowed a logical panel layout but the front panel at eye level is all electronic with a combined radar and projected map display flanked by two TV tabular displays and associated keyboards. The radar hand controller sits on a pedestal between the operator’s knees and the TV. Tabs allow dialogue with the computer, which stores 65,000 bits of information in its memory.

Why two seats? That debate is endless. I believe that with high speed, low level bombing the probability of mission success is much improved by splitting the workload. The single seat solution can be mechanised- the early Tornado investigations did it – but the result is very much less flexible than the two seat version. It is easy, for example, to fly a single seat auto terrain following bombing attack through weather to take out a planned target.

But if another type of target is spotted on the way, if a change of target is ordered while en route, if an evading diversion from planned track is made necessary preventing planned navigation updating, if a single failure occurs necessitating manual instead of auto terrain following – in any of these not unusual cases you would be glad to have someone to share the extra workload while you keep the aircraft out of the weeds.

Starting Up

Start up is simple. The aircraft auxiliary power unit (APU) is already running the right gearbox, so pressing the starter switch to ‘Right’ simply clutches in that engine to its own gearbox. The two engine gearboxes can be connected via a cross-drive clutch which closes automatically and consequently no services are lost from the failed engine. By use of the cross-drive clutch, either engine can be started from the APU.

The cockpit, with climate conditioning on or off, is quiet. Cockpit noise levels in the Tornado at 800 knots indicated airspeed are remarkably low and certainly do not affect crew chat levels.

Preflight checks take up very little time. Most systems have their own built-in test equipment and the only ‘extra’ check on Tornado is to sweep the wing once each way before starting to taxi. Nosewheel steering is permanently engaged but it can be cut out on the stick paddle switch in case of malfunction.

While taxying, we can check on the ‘other way of stopping’ – by throwing engine thrust into reverse! Rocking both throttle levers left through an over centre action spring selects both sets of spoilers to the lift dump mode and deploys the engine thrust reverser buckets. The throttles can be used in the normal way with the reversers deployed; in other words, moving throttles forward increases reverse thrust. So even a failure of both wheel braking systems won’t prevent us from stopping and we can slow or stop on ice without directional problems- another bonus in Europe.

Running up the Turbo-Union RB199 engines against the brakes prior to takeoff shows the rapid wind up times that the electronic control system provides. The link from throttle to engine is all electronic and gives the nicest control that I have ever found.

You can slam from idle to combat power anywhere in the flight envelope. A particular engine speed can be set up very quickly and very accurately – a function of rapid response, digital gauges that can be read to 0. 1 per cent and a total lack of creep and sponginess. But the real beauty of these small three spool fan engines is revealed to us when we get the machine into the air. The RB199 has the highest thrust-to-weight volume ratio of any operational turbine engine in the world today, giving the Tornado a Mach 2+ level flight capability with engines small enough to look at home on a business jet.

A Joy to Fly

Max dry power is held against the toe brakes, then minimum reheat, and finally the throttles are slammed to full combat power as the brakes are released. Acceleration with a typical load of eight 1,000 pound bombs is good and the aircraft is lifted off in about half our 6,000 foot runway.

When the flaps are raised from their mid 35° position, they retract only to the ‘manoeuvre’ setting of 7° flap, 11° slat. The wing then cleans up automatically as incidence is reduced for cruising. With manoeuvre extended, we can maintain very high turn rates at sea level and we are not going to be much above that level during the first part of this sortie.

With the flap/slat retracted, we settle down at the best range speed to fly to the target and deliver our payload. Normally we would simply put the autopilot on ‘trackhold’ and let the automatic flightplan take us there. We can choose a pitch channel controlled by the terrain following radar with barometric or radar height hold, depending on the desired altitude and monitor the route on the projected map (front seat) and radar in the rear. Fuel flow is back to a very low figure, even with our eight 1,000 pound bombs, and the navigator will update the nav system two or three times during the first half hour to guarantee the system accuracy that will be required if the weather is poor and we have to lay down the bombs blind. Updating is done by radar and laser ranging and, in visual conditions, the pilot can switch into the loop by using the fixing marker in the HUD.

Let us look at the aircraft’s handling traits en route to the bombing range.

Pulling the aircraft into a turn at our 350 knots transit speed automatically extends manoeuvre devices (flap and slat) giving no trim change. The aircraft is changed from a high wing loading maximum range machine into a lower wing loading, highly manoeuvrable ship. Stick forces are light to moderate and harmony between pitch and roll is excellent. The triplex fly-by-wire system provides superb stability and response, making the aircraft a joy to fly clean or with a heavy payload, at sea level or at 30,000 feet, at 140 knots or at 800 knots. Full stick roll rate is identical between zero and four in 25°, 45° or 67° wingsweep positions and between Mach 0. 5 and 1. 0 at all altitudes and with all loads. Stick force per g does vary slightly with Mach number, stiffening up a little at supersonic speed but remaining always in the ‘pleasant’ category.

Opening up to max dry power, we quickly reach the. Mach 0. 8/500 knots IAS limit for forward-swept wing. With manoeuvre devices retracted, we are back to a high wing loading, low gust response ride even with the wing forward.

The wing is usually on the strike variant using the wing lever inboard of the throttle box. The air defence variant has auto sweep, which we would also like to see on the strike version. There is no trim change during sweeping and very little change of handling qualities – only a slight change in background hum as you put the wing all the way back to 67°.

The wing mounted spoilers provide additional roll control with the wing forward. They are switched out of the circuit at sweeps of greater than 50°. Their effectiveness becomes negligible at higher wing angles. The differential tail now provides both pitch and roll control. The main gain to the strike pilot from sweeping fully back is that the wing attains a lower lift curve slope and reduces its area by about five per cent as the inboard trailing edge gets tucked away into the fuselage. This gives ride comfort in low level turbulence which is unequalled by any other aircraft flying.

The smoothness of the ride here at 200 feet, Mach 0. 92 isn’t just an added tourist attraction. It makes it possible to monitor the terrain following track keeping and the HUD attack symbology without distraction or fatigue in all weather attack conditions.

Delivering the Ordnance

Approaching the bombing range, let’s set up for a single pass laydown attack, dropping our eight 1,000 pound bombs in a stick. With terrain following selected and hard ride, we can be sure that we are following the ground contours as closely as any aircraft at 600 knots can do.

Wind down the ‘clearance height’ setting knob to the minimum level and you are down in the weeds giving the hardest possible task to any defending weapon system. It’s also comforting to know that there is triplex attitude monitoring in the automatic terrain following system and that you’ll get an automatic pull-up before the aircraft is handed back to you in the event of a failure. The only trips to date with the system have been caused by discrepancies in sensitivity between the different altitude sensors, finally ironed out after many hours of terrain following flight testing over the Black Forest in southern Germany.

At about 30 kilometres from the target, the navigator selects the weapon package, the ‘attack’ mode on the TV display and the ‘stabilised’ mode on the combined map and radar display. The stabilised mode brings the computed target or radar offset to screen centre overlaid with an aiming marker. An automatic radar identification tilt facility along with the stabilised mode makes the task of target identification and possible marker position refinement a low workload task.

In the front seat, you will be checking the attack progress through the HUD with hand on stick ready to take over from the autopilot if you should be able to identify the target visually and see an aiming error.

As the navigator refines the target position using his own hand controller, you will notice the HUD aiming marker move to superimpose on the new target ground position and also feel the aircraft react to the autopilot adjusting the aircraft track to achieve the correct release solution. The throttles can be left alone since IAS is being controlled by the auto throttle.

A circle around the aircraft symbol in the HUD unwinds to show the number of seconds to automatic bomb release. Some time before the pilot would see the target in visual conditions, the navigator will have finished aiming and the laser range finder will be ranging on the target position to give the weapon system very accurate plan range and aircraft height information. You will squeeze the stick mounted pickle button, which is the pilot’s ‘commit’ signal. You can prevent release at any time up to the last second by releasing the button.

If the European weather maintains its usual form, your only contribution to the bomb drop as the pilot will be to monitor the whole exercise to ensure safety. There is absolutely nothing to be gained by switching to a ‘Phase 2’ attack – bringing the pilot into the loop. But if the target is seen anywhere but under the marker, or if a more attractive alternative target is seen, you can use the ‘eyeball’ on the hand controller to move the marker accurately over the new target and let the autopilot take care of the track change required, or you can take over control of the aircraft to hand fly it to a release point. In this case, you’ll be glad the Tornado’s handling qualities are so consistently excellent, because dragging an aircraft out of autopilot to pull a hard turn at 200 feet and 600 knots with only two or three seconds to go to release demands nothing less than everything.

The stick of eight 1,000lb bombs rippling off the belly comes through as a slight shuddering and results in noticeable acceleration, having ditched the drag. The plan would now be to stay fast and low back to where it’s friendly. But let’s have a look at Tornado’s handling characteristics at high Mach numbers.

High and Hot

We have enough fuel remaining to investigate Tornado’s clean performance, giving a taste of the capabilities of the air defence variant also operated by the RAF. This version uses the Tornado’s varied characteristics to achieve a different sortie profile. With four semisubmerged Skyflash air-to-air missiles and four Sidewinders, it will cruise out at medium altitude and remain on combat air patrol with wing forward. Its radar incorporates a multitarget track-while-scan facility and gives excellent lookdown performance. After high level target contact, the air defence tornado will accelerate to a high supersonic speed, giving a capability to take out targets to altitudes well in excess of 60,000 feet, by using a combination of aircraft zoom and missile performance. Interception can be carried out ‘hands off’ and in all weather, right down to the trees.

When approaching Mach 0. 8 at 25,000 feet, the wing is brought back to the mid 45° position which compared to 67° gives reduced drag in manoeuvring. Leading edge slat is still available at 45° but the manoeuvre flap is inhibited. Carefree manoeuvring up to high incidence is provided courtesy of the spin prevention and incidence limiting system. The system allows the pilot to get the maximum performance out of the aircraft with total confidence – a requirement that is here to stay in the modern combat aircraft.

Slamming to combat power at 25,000 feet starts a healthy airspeed increase and the wing is swept right back at about Mach 0. 92. The 45° wing is, of course, good for high supersonic speeds, but we are after the optimum acceleration. There is slight Mach ‘noise’ at Mach 0. 98 but all is smooth and quiet at the jump up to supersonic speed and the optimum acceleration is achieved by building up to around 550 knots IAS and then maintaining that in a climb to the tropopause.

At the tropopause, our rate of Mach progress depends, of course, on the outside temperature. You can put in full rudder pedal at Mach 2 – or indeed anywhere else around the flight envelope. The sideslip is automatically kept within limits, and Dutch roll damping is good.

Let’s cut the afterburner now and drop the nose to pick up 800 knots IAS on the way home. This is the only aircraft that I have flown cleared to such speeds and surely it says all there is to say about the suitability of the airframe designed to spend most of its life hammering along at low level. Even at this speed the turbulence encountered on plunging through cumulus cloud comes through as a very soft edged aircraft reaction.

Airbrakes can be selected at any time but they are scheduled to restrict their angle in relation to Mach number and never give an eyepulling deceleration. They sit at each side of the fin and are trim change free. But we don’t need airbrakes to decelerate from 800knots. Idle power has the desired effect initially and below about 600knots the wing can be swept froward to 45° which also helps.

Landing Is Half the Fun

An experience equally impressive as smouldering along at 800 knots IAS is cruising home low level at best range speed. Very low fuel flows can be achieved from the RB199 fan engines developed specifically for this airframe.

The final benefit of the Tornado design to be demonstrated is built in _with a war in Europe in mind. Dependence on long concrete runways is going to be an embarrassment when the tanks star t to roll. What’s the advantage of 1,000 feet takeoff performance when it takes 3,000feet to stop when you get back?

Back at home base the weather is 200 feet and a mile in rain and we position for an instrument landing system (ILS ) approach. Mid flaps and gear are dropped at 300 knots and 250 knots respectively. The pattern is flown at 200 knots with ‘auto approach’ selected and speed is bled off to 140 knots for final approach after full flap has been lowered. The auto throttle is optimised for the approach and IAS is kept throughout to within three knots of that selected.

At 200feet, the runway lights appear out of the murk and the autopilot is disconnected by the thumb switch on the stick. Roundout and, as the main wheels touch down,the lift dumpers extend and kill any tendency to float. At the same time the reverser buckets snap out on about 85%rpm and as the nosewheel touches,both engines are slammed to max power and the brakes are stamped on. The resulting deceleration is the nearest thing to a carrier deck landing that an air force pilot is likely to experience. In no wind,you can come to a full stop with ease in less than 1,500feet.

The ser vice chiefs are glad to see Tornado achieve mission readiness in Europe. The need for a low level strike aircraft that can operate in any weather or light conditions is clear. Of all the air-to-ground weapons systems in Europe today, the Tornado and the USAF F-111s have the best chance of getting through with the goods. And it’s nice to know that besides being effective,RAF Tornados crews are going to enjoy flying it too. D

David Eagles joined the Royal Navy in 1953 and received his flying training with the US Navy He served in the Fleet Air Arm in various carriers and squadrons before graduating from Empire Test Pilot’s School in 1963. In 1968 he led the Buccaneer aerobatic team at the Farnborough Air Show. He left the Royal Navy in 1968 with the rank of Lieutenant Commander to join the British Aircraft Corporation (now British Aerospace) as an experimental test pilot. In 1970, he was appointed project pilot on the Tornado programme and, in 1971, senior experimental test pilot. He later became chief test pilot in 1977.