Libya's war from above: on board the RAF's E-3D spy plane

Thirty thousand feet above Libya, the war against Mumamaar Gaddafi is directed against the roar of aircraft noise by men hunched over banks of computer screens.

This is Magic 52, the RAF E-3D spy plane which is in charge of the effort to protect Libya's civilians from the dictator.

Last week The Sunday Telegraph became the first newspaper on board the RAF jet whose equipment is one of Britain's most closely-guarded military secrets.

From the airborne command, control and communication centre, a crew of highly-trained specialists direct every part of the bombing campaign.

In the course of a nine-hour sortie, they can direct 100 aircraft to carry out strike after strike against the Libyan dictator's forces.

On board highly-trained RAF personnel with access to Britain's most sensitive military secrets co-ordinate reconnaissance, refuelling and finding and attacking Gaddafi's military.

We were given unprecedented access to the secret war when we joined "Magic 52", the call sign of Zulu Hotel 101 - one of three E-3D Sentries committed to Operation Unified Protector, the Nato mission enforcing United Nations Security Council resolution 1973.

Much of what we witnessed was classified but Government spy chiefs have allowed us to report on some of the events which took place last Tuesday.

From its Forward Operating Base at Trapani in Sicily, Magic 52 flew to a position 80 miles off the Libyan coastline where it remained for the next seven hours, flying in a orbit close to Sirte, Colonel Gaddafi's home town.

On board its team of intelligence analysts and weapons experts sat glued to computer screens searching for signs of enemy activity in the air, at sea and on land.

In the sky below dozens of Nato jets began filling the "battle space", ready to strike at any enemy forces entering the "kill chain" - the process by which targets are identified, evaluated and destroyed.

After three hours "on station", an RAF strike patrol composed of two Tornado GR4s and a Typhoon, informed Magic 52 that they had identified four armoured vehicles near to rebel held town of Misrata.

The vehicles were Russian-made T-55 main battle tanks - one of the major weapons in Gaddafi armoury.

The aircraft requested permission to engage the tanks and the Sentry's mission team immediately swung into action.

All three jets needed to refuel from one of the air-to-air tankers also being coordinated by the Sentry before the attack could take place.

By 5pm, 30 minutes after the vehicles had first been identified, the attack was under way.

Two Tornados, each carrying two Paveway 4 laser-guided bombs armed with fuses designed to detonate the explosive once the weapon had penetrated the tank's armour, prepared to attack.

The Libyan soldiers must have watched in terror as one tank after the other exploded in a ball of flame and burning metal as the bombs struck.

Escape was impossible and no survivors were reported.

The attack's success was greeted with muted satisfaction by the RAF crew - there were no high fives, no cheering, no back-slapping, just professional pride in a job well done.

The three RAF jets refuelled for a second time before heading for their next target close to the town of Brega, where some days earlier a Libyan radar station had made the fatal mistake of emitting a radar signal.

It was now in the "kill chain". Minutes later an RAF GR4 fired a highly sophisticated Brimstone missile which locked onto its target destroying it seconds later.

There are seven Boeing E-3D Sentries in service as part of 8 Squadron based at RAF Waddington near Lincoln.

Since they came into service in 1991, the aircraft have served around the world and on operations in the Balkans, Iraq and Afghanistan.

Each aircraft is named after one of the Seven Dwarfs - Magic 52 is "Doc" a comically inappropriate name for the RAF's premier spy in the sky.

The aircraft is manned by a crew of 18; four flight deck crew, three technicians and an 11-man mission crew, which comprises a tactical director, a fighter allocator, three weapons controllers, a surveillance controller, two surveillance operators, a data-link manager, a communications operator and an electronic support measures operator.

The mission teams are responsible for controlling the air battle and enforcing the no fly zone. They must be able to identify every aircraft and ship in the battle space and differentiate between friend and foe.

In a fast-moving, three-dimensional air war, coordination is key.

All air sorties are planned by Nato's Combined Air Operation Centre (CAOC) at Poggia, near Venice, but the missions are coordinated by the team on board the Sentry.

Fast jets must be able to fly their missions safely without fear of collision, targets must be prioritorised and crucially the E-3D Sentry must coordinate the inflight refuelling operation.

The responsibility for refuelling fell to 25-year-old Flight Lieutenant Mike Clarkson, one of the mission team's weapons controllers.

Operating the refuelling programme demands total concentration and a large amount of what the RAF calls "capacity" - the ability to evaluate many different pieces of information at the same time.

"It's mentally exhausting and the time passes very quickly," said Flt Lt Clarkson.

"In a typical seven hour mission we can be responsible for coordinating the movements of up to 100 aircraft. I will usually have nine different people speaking to me at the same time through my head set, four from within the aircraft and five from outside. There is a plan but it must remain fluid and it always changes. If the refuelling programme fails then every thing else will fail so you can't afford to have any mistakes."

During the mission the team controlled more than 100 aircraft, 20 of which were air to air refuelling tankers.

During the mission's busiest period, the crew were simultaneously controlling the operations of 30 combat aircraft, while coordinating a complex refuelling programme and searching the Libyan desert for hostile radar activity.

"The enforcement of the no-fly zone is all about protecting life," said Flight Lieutenant Vaughan Arnall, the aircraft's tactical director and the officer responsible for controlling the combat phase of the mission.

"No attack is ever approved if there is any risk of killing civilians. A collateral damage assessment is always conducted and the aircraft will only attack if it is carrying the appropriate weapons."

The aircraft's brain is contained within a circular shaped radar dome which sits above the aircraft.

The dome contains more than five tonnes of equipment but being shaped like a wing it achieves "zero weight" when airborne and can scan the horizon six times a minute.

The radar is so vast that it requires its own mini power station which generates 83,000 volts to keep it operational - the rest of the equipment on board is powered by the four jet engines.

Almost every piece of electronic surveillance equipment on board the Sentry is categorised as top secret but none more so than the sensors operated by Flight Sergeant Phil Thornton, 43.

Flt Sgt Thornton operates "Yellow Gate", one of the most secret pieces of equipment on the aircraft.

The equipment searches for the electronic signals emitted by enemy radar which can identify the location of surface-to-air missiles.

Even our allies cannot see it in operation: it is marked "UK Secret. UK Eyes Only".

Most of my questions about Yellow Gate received the answer: "Sorry that's classified."

When I asked what his work entailed, Flt Sgt Thornton said: "It is like playing a computer game.

"You can't just view it as a flat screen I have to be able to see into the battle space and develop a situational awareness so that I can relay the information to whoever needs it. It is a very important job and you have to be able to multi-task, have a lot of capacity and be very flexible. Things can change very quickly."

With the vast array of sensors on board the mission team can identify an enemy target, relay the information back to the COAC at Poggia and call in a strike operation in minutes.

Flt Sgt Thornton continued: "Our job is to speed up the "kill chain".

"We have managed to do that in under a minute. Speed is vital. If you had a main battle tank attacking civilians you want to be able to destroy it pretty quickly."

As the sun begins to set over the Mediterranean, the mission draws to a close, arriving back at Trapani airbase shortly after 10pm.

Some members of the mission team have not left their seats such has been the intensity of the workload.

The crew disembarked, all tired, some exhausted and in 24 hours time they will do it all again, working one day on one day off 30,000 fett above the battlefield - until the war in Libya is over.