According to the investigation after the incident, although the IFF equipment of the tornado was checked in compliance with regulations, the Patriot Missile Company did not receive a response from the IFF in Mode 4. Although mode 1 reply is also available under the coalition standard, the database of the Patriot Missile Company does not record the mode 1 code comparison, and the missile company needs to use the data link to receive the codes shared by other units and then manually display the comparison - however, the communication of the missile alliance The kit has not yet arrived, and the missile battalion can only be contacted through the radio relay of the adjacent missile company, and naturally cannot receive the Mode 1 code.
The problem caused by the lack of a communication kit is not only that, another major problem caused by radio alone is that the missile company cannot receive airspace images to better understand the surrounding airspace movements. which in number list turn affects the missile company operator's perception of the true identity of Yahoo 76. judgment. At the same time, although other U.S. early warning aircraft that were also tracking Yahoo 76 received the IFF reply from the wingman Yahoo 75, they quickly identified Yahoo 76 as a friendly unit and integrated their trajectories into the airspace imagery. However, the hit missile company not only could not share airspace images because there was no data link, but also because of delays in radio transmissions, they chose to respond as quickly as possible to receive denials from friendly forces.
The British military investigation unit also pointed out that the Patriot has a strong and complete database, which records the flight profile characteristics of almost all known anti-radiation missiles in the world, but the side effect of this is that the flight profile of friendly aircraft is very likely to match a certain missile. high. Although the battalion headquarters can share the known characteristics of Iraqi anti-radiation missiles to conduct more accurate screening in the missile company database, the missile company that caused the accident has no data connection with the battalion headquarters, and the battalion headquarters has not provided screening targets. directory, allowing the hit-miss missile company to manually sift through the database.