The 51st (Highland) Searchlight Regiment, Royal Artillery was a Scottish unit of Britain's Territorial Army (TA) formed for air defence just before World War II.

It later served as an anti-aircraft (AA) artillery unit in the North West Europe Campaign 1944–45, and continued in the postwar TA into the 1950s.

The unit's origin lay in two independent AA Companies of the Royal Engineers (RE) formed in Aberdeen and Dundee in 1935 and equipped with searchlights.

[4][25] LAA regiments at this time comprised three batteries of three troops, each equipped with six towed Bofors 40 mm guns using 'Stiffkey Stick' sights.

Two weeks later, Canadian troops captured Ostend, and 124 LAA Rgt with the rest of 75 AA Bde moved up the coast to defend it.

[27][28][29][30] On 9 January 1945, four Bofors of 411 LAA Bty hit and sank a German Biber midget submarine operating off South Beveland.

[31][33] After 76 AA Bde completed its disbandment in the first two weeks of April 1946, 124 LAA Rgt stayed on as part of British Army of the Rhine, but was placed in suspended animation on 8 June.