On 6 March 1945 (concurrent with the activation of Project Alberta), the 1st Ordnance Squadron, Special (Aviation) was activated at Wendover, again using Army Air Forces personnel on hand or already at Los Alamos. Its purpose was to provide "skilled machinists, welders and munitions workers" and special equipment to the group to enable it to assemble atomic weapons at its operating base, thereby allowing the weapons to be transported more safely in their component parts. A rigorous candidate selection process was used to recruit personnel, reportedly with an 80% rejection rate. The 509th Composite Group reached full strength in May 1945.