The Italians first, and later the Germans, could not understand how they found Allied planes on their tails when they were coming to bomb Malta.

For quite some time, Malta had its own secret weapon with which it ably defended itself. In fact, the whole legend that the Italians always preferred to bomb from very high altitudes is not very exact: it was not a question of preference but because the Italians found themselves attacked by the few planes Malta had to defend itself.

The Germans then took over in January 1941 with heavy raids and bombing and yet they too suffered huge losses because the island's defence forces were ready for them.

This may have prompted the Germans to leave Malta alone and focus on helping Rommel in North Africa - a decision that ultimately saved Malta from an invasion that had already been planned.

So what was Malta's secret weapon?

According to Major Tony Abela, who delivered a lecture on this subject at Din l-Art Helwa last week, based on his book Malta's Early Warning System during World War II, this secret weapon was radar. It was through radar that the Maltese defences found out that enemy planes were on their way, the number of planes and from which direction. They could actually monitor them from the moment they took off from Sicily.

Radar also played a very important part in stopping the raid by Italian fast boats on the Grand Harbour. Through radar, the Maltese had already noticed the mother ship approaching and all defences were alerted. When the Italians came, the Maltese were ready for them. (Major Abela also said two Italians were captured alive and their replies during interrogation make very interesting reading).

In the years prior to World War II, the word 'radar' had not even been invented. It was actually coined by the US in 1942 when it had already been in use for some years.

Malta played a very important role in the development of radar. In fact, the structure called 'Il-Widna' just off Maghtab was a forerunner of radar and the first time such an experiment had been carried out outside the UK.

It could be said that radar was almost discovered accidentally, when the BBC was investigating the interference in radio reception when a plane passed between the transmitter and the receivers. In Great Britain it was called RDF: Range and Direction Finding. 

This very experimental system was sent to Malta in 1939, just before the start of the war. Called 241 AME, the first station was set up at Dingli. Later on, the same area was to get more and more radar stations and the buildings erected to house the machinery and lodging for the crews is still visible today - some have been converted to villas and others are derelict. Just behind Bobbyland Restaurant, for instance, there are remains of such radar-connected buildings.

Just before war was declared, in September 1939, tests were carried out regarding calibration and by the time the war began the primitive radar could read the height of the incoming raiders and the direction.

The first radar, being experimental, was indeed primitive and unsuited to the Maltese climate: the summer heat wrought havoc with the diodes and the radar could only be used for eight hours a day. Also, the antennas fell victim on the strong winds on the Dingli Cliffs and were repaired (and improved) at the Malta Dockyard.

Later on, when the second radar station was added to the Dingli area, the operation went underground (although it was never bombarded). Some underground rooms are still to be found in the area: one is the engine room with openings on to the side of the cliff. The farmers in the area, seeing smoke being emitted from these rooms (due to the high heat) thought the British were cooking at a time when the Maltese faced rationing.

The fact is that radar was a completely new concept and was kept secret even from the British themselves, who had no idea what the group up at Dingli was doing, except sunning themselves, as they thought. It was only when, just before the war began and the first Dingli radar was instrumental in finding three British planes that had got lost and guided them to Malta, that the unit had some well-deserved recognition even from official quarters.

Later on, more radar stations were added in order to cover the entire area of Malta and to also include shipping, as well as planes. Such stations were set up at Madliena (which was to prove very important in the invasion of Sicily), tas-Silg and again at Dingli. Still later, a radar station was added in Gozo first at Ta' Dbiegi and later up on Ġordan.

The remains of many of these radar stations can still be found, including barbed wire dating from the war, huts and other buildings. Also extant are the places where the British (only two or three Maltese worked in these secret radar stations, and then only as cooks) were billeted: Deiril-Bniet in Dingli and St Paul's Farm nearby.

By the time the Sicily invasion took place and the war was over for Malta, Malta had become one of the best defended places in the British Empire. More radar stations were added at Comino, Marfa Point, Fort Campbell, etc.

It was the advance warning provided by the radar that enabled the people of Malta to get to the shelters and so helped limit the number of people killed as a result of the many air raids.

The beginning, as said, was very experimental. The intercepted signals were passed on telephonically to the Valletta filter room where they were interpreted first in a basement mistakenly claimed to have been in Merchants Street but which was, in fact, actually in Scots Street, and later underneath Castille.

At first, the early warning that radar afforded was used by the British to advise their pilots from where the enemy planes were coming so that the British planes could get away from them and avoid attack. Later on, it dawned on the British that they could use this information to pounce on the raiders and catch them unawares. 

There are stories within stories in Major Abela's account.

At first, since there was the direct threat of a German invasion, all notes had to be burned, so there are no records of the first operations. Major Abela considers himself lucky to have stumbled on eyewitness accounts either of the officers themselves or as told to their children, and to have actually met some of them (one is still alive at the age of 94). Piece by piece, through research in the Kew Archives and elsewhere, the story has been pieced together.

One of these stories is a sad one: it concerns a Flight Lieutenant Powey, who was due to return to Britain, having completed his tour in Malta, Instead of taking it easy on his last day here, he joined his mates in investigating a Juncker that had been brought down near Peter's Pool. But the plane exploded, killing them all - including Lt Powey - who is therefore buried in Malta.