According to Klass, the Westinghouse technician at Shahrokhi airbase stated that only the first F-4 reported failing equipment, and that this F-4 was known for equipment failures with a long history of electrical outages, having been repaired only a month before the incident. Klass cites a McDonnell Douglas repair supervisor's opinion that the F-4's radar could have been in "manual track" mode, causing a wrong interpretation of the radar lock.[1]