ℹ️ ➖➖➖ The MIM-104 Patriot is a surface-to-air missile (SAM) system, the primary of its kind used by the United States Army and several allied nations. It is manufactured by the U.S. defence contractor Raytheon and derives its name from the radar component of the weapon system. The AN/MPQ-53 at the heart of the system is known as the "Phased Array Tracking Radar to Intercept on Target" which is a backronym for PATRIOT. The Patriot System replaced the Nike Hercules system as the U.S. Army's primary High to Medium Air Defense (HIMAD) system and replaced the MIM-23 Hawk system as the U.S. Army's medium tactical air defence system. In addition to these roles, Patriot has been given the function of the U.S. Army's anti-ballistic missile (ABM) system, which is now Patriot's primary mission. The system is expected to stay fielded until at least 2040. During the late 1980s, tests began to indicate that, although Patriot was certainly capable of intercepting inbound ballistic missiles, it was questionable whether or not the MIM-104A/B missile was capable of destroying them reliably. This necessitated the introduction of the PAC-2 missile and system upgrade.
For the system, the PAC-2 upgrade was similar to the PAC-1 upgrade. Radar search algorithms were further optimized, and the beam protocol while in "TBM search" was further modified. PAC-2 also saw Patriot's first major missile upgrade, with the introduction of the MIM-104C, or PAC-2 missile. This missile was optimized for ballistic missile engagements. Major changes to the PAC-2 missile were the size of the projectiles in its blast-fragmentation warhead (changed from around 2 grams to around 45 grams), and the timing of the pulse-Doppler radar fuse, which was optimized for high-speed engagements. Engagement procedures were also optimized, changing the method of fire the system used to engage ballistic missiles. Instead of launching two missiles in an almost simultaneous salvo, a brief delay (between 3 and 4 seconds) was added in order to allow the second missile launched to discriminate a ballistic missile warhead in the aftermath of the explosion of the first.
PAC-2 was first tested in 1987 and reached Army units in 1990, just in time for deployment to the Middle East for the Persian Gulf War. It was there that Patriot was first regarded as a successful ABM system and proof that ballistic missile defence was indeed possible. The complete study on its effectiveness remains classified.
📑 ➖➖➖ In 1991, Saudi Arabia became the first Middle East customer of the Patriot missile system and maintains the largest missile defence force in the Middle East. Saudi Arabia’s ballistic missile defence capability is designed to defend against its primary adversary: Iran. Saudi Arabia is one of 14 nations to have purchased the technology. Saudi Arabia has used the Patriot missile defence system to defend itself twice against the Houthi rebels, most recently in March of 2018. On both occasions the main target of the attack was the Riyadh airport, the first attack in 2017 was successfully intercepted. March’s attack, however, still has some surrounding uncertainty. The Houthis fired seven missiles, and footage of the attack shows a potential failure of the Patriot system in its targeting of the missiles.

▪️ 🛠 Designer Raytheon
▪️⏺ Defended area: 15-20 Km against ballistic missiles
▪️#️ Missiles per launching station: 4 PAC-2
▪️ 📡 Radar Range: 150+ Km
▪️⏩ Speed: 5,000 Km/h
▪️Flight Ceiling: 20+ Km
▪️📏 Missile Length: 5.2 m
▪️ ↔️ Diameter: 25 cm
▪️⬇️ Weight: 320 Kg

Ref: Wikipedia; missiledefenseadvocacy; nato