66th Light Anti-Aircraft Regiment, Royal Artillery, was an air defence unit of the British Army formed in Northern Ireland during World War II.

102nd Heavy Anti-Aircraft Regiment, Royal Artillery, was forming in Antrim, Northern Ireland, just as World War II broke out in September 1939.

On this occasion the regiment suffered a direct hit on a Lewis gun position with the death of three men, and considerable damage to 175 LAA Bty's HQ at Clonaver Camp.

[5][6][18] In the autumn of 1941 the regiment was able to send detachments to practice camps for live firing, and new Bofors guns and Kerrison Predictors[19] were arriving.

[6] The reinforcement draft was absorbed and then all the men of lower medical categories were posted to the D Trp of each battery, which were then detached to form a new 459 LAA Bty on 19 February 1942.

Dover was under occasional shelling from German long-range guns, which had gained the area the nickname of 'Hellfire Corner'; the regiment suffered some damage from these.

It then returned to AA Command for a few weeks dispersed across Hampshire and along the Sussex coast (where C Trp of 176 Bty at Littlehampton claimed a hit on a raider).

First, in early June the guns and equipment were shipped to Haifa in Palestine and Beirut in Lebanon, then the personnel entrained for Suez, where on 30 June 175 and 176 LAA Btys boarded HM Transports Empire Trooper and Duchess of Bedford, while the main body (RHQ, REME, Royal Signals and 276 LAA Bty) boarded the Orbita.

The regiment began landing on 13 July, when 176 LAA Bty immediately deployed 12 guns to defend the port; these were in action that night.

[27][29][30] The regiment spent August defending Syracuse against 'slight air activity' while the ground troops completed the capture of Sicily and prepared for the assault crossing of the Straits of Messina (Operation Baytown) on 3 September.

The war having moved on, the regiment caught up on some training, including anti-tank practice, while the rear parties and transport arrived from Egypt.

The advance party and 175 LAA Bty crossed the Straits of Messina on 15 February, but en route they were diverted to rejoin 62 AA Bde guarding the Foggia Airfield Complex.

The regiment deployed as follows:[32][33][34] (The airfields at Lesina and Sterparone were not actually in use at the time because of mud, and the troop at San Severo was flooded out of its initial positions.

On 3 September 66th LAA Rgt was ordered to cease AA operations and to take up transport duties for Force 140 being prepared to go to Greece, where the German withdrawal was well under way.

They were to land in Greece (Operation Manna) to 'show the flag' in Athens, disarm the Greek security battalions established under German occupation, open up ports for relief supplies, and generally to act as arbitrators in local disputes.

[32][39] HMS Ajax arrived at Piraeus on 15 October and landed the troops next day; RHQ was established at a flour mill in the town.

Meanwhile, the rest of the regiment continued unloading vehicles at Piraeus and established battery HQs in Faliron, while the second-in-command, Maj C.J.

During November the rest of the men and vehicles arrived from Italy and the Middle East, and the regiment carried out general transport duties for Arkforce around Athens and for relief supplies to the interior.

66th LAA Regiment was left in the dark, relying on BBC broadcasts for information, but increased its guards and sentries and prepared platoons of 30 lorries for troop movements, one for duty with 23rd Armd Bde and one taking reinforcements from Piraeus docks into Athens.

Next day 139 Infantry Bde HQ arrived and took control of the Piraeus and Faliron area, including 66th LAA Rgt, which was ordered to find foot patrols as well as its transport duties, which included sending lorries to collect British detachments cut off in the city and supplying rations to the Greek Police and National Guard.

Infantry units took over the defence of Faliron under Lt-Col Grandage's command ('Granforce') and on the night of 17/18 December operations began to advance up the road and link up the British positions.

Daily convoys to Athens resumed and the regiment's lorries cleared the backlog of supplies that had piled up at the docks and airfield.

[32][39][42] The British forces in Athens began an offensive against ELAS on 2 January 1945, during which 66th LAA Regiment suffered minor casualties to men and vehicles from artillery fire.

[32][39][43] On 13 February 1945 the regiment was warned that it was to be disbanded and reformed as general transport (GT) companies of the Royal Army Service Corps (RASC).