In July 1984, a contract was formally issued for the upgrade of a total of 18 Mirage IVAs to carry the ASMP missile in the place of traditional bombs; these aircraft were redesignated Mirage IVP (Penetration). The conversion of Mirage IVAs to IVPs involved a large number of modifications and re-workings of the aircraft. A deep centerline pylon was added, which could accommodate either a single ASMP missile or a CT52 reconnaissance pod. The main radar and electronics suite were removed and replaced by newer counterparts; other modified systems included the navigation system, flight control system, and various elements of the cockpit. On 12 October 1982, the first modernised Mirage IVP performed its first flight; it re-entered active service on 1 May 1986.