frm1 on open filter by equipmentID, recordsource - Equipment (Table)
Subfrm1 recordsource - SELECT PMTask.TaskID, PMTask.EquipmentID, PMTask.Task, PMTask.StartDate, PMTask.Frequency, Max(PMTaskDetails.CompletionDate) AS MaxOfCompletionDate
FROM PMTask INNER JOIN PMTaskDetails ON PMTask.TaskID =...