The Allied campaign continued with the invasion of mainland Italy, first across the Strait of Messina (Operation Baytown) on 3 September, where 80th HAA Rgt (194 and 250 HAA Btys) provided AA cover from Messina, followed on 9 September by landings at Salerno (Operation Avalanche). For 'Avalanche', 252 HAA Bty was in No 4 Beach Group under 12 AA Bde. This time there was no surprise, and the LSTs and LCIs came under air attack and then heavy artillery fire as they approached the beaches. However, casualties among the AA troops were light and all the breach groups landed successfully: the first HAA guns were in action 4–6 hours after landings began. Opposition remained strong, and reinforcements poured into a tightly constricted beachhead while heavy fighting continued nearby. Although early warning and communications again proved a problem, the HAA sites were able to use their GL radar to fire concentrations against raiders. On 17 September the advance from the beachhead towards Naples began: so eager were the AA units that Brigadier Mortimer Wheeler of 12 AA Bde proposed using a column of AA troops to break out towards Pompeii, though the scheme was vetoed by X Corps.