Sa'ar 4.5-class missile boat

The Sa'ar 4.5-class missile boats (סער 4.5) is a class of Israeli Sea Corps missile boats designed and built by Israel Shipyards Ltd. for Shayetet 3 flotilla as an improved and stretched Sa'ar 4-class missile boat. There are two different subclasses that are both named Sa'ar 4.5. The first subclass was initially called Chochit (חוחית), but renamed to Aliya (עליה). Two Aliya-subclass boats are in service with the Mexican Navy. The second subclass was initially called Nirit (נירית) but renamed to Hetz (חץ).

History
The original construction plan for Sa'ar 4.5-class missile boats included:

Two helicopter-equipped boats (Aliya subclass):
 * INS Aliya
 * INS Geula

Three ordinary missile boats (Hetz subclass):
 * INS Romach (launched and commissioned in 1981),
 * INS Keshet (launched and commissioned in 1982) and
 * INS Nirit

The keel of INS Nirit was laid in 1984 but the construction ceased due to lack of funds and it was finally launched in 1990 and commissioned in 1991 with some modern equipment, eventuality renamed to INS Hetz. Consequently the older INS Romach and INS Keshet were upgraded to match INS Hetz's specifications.

INS Kidon, INS Tarshish, and INS Yaffo' commissioned in 1997, 1997, and 1998 respectively. Particularly INS Kidon and INS Yaffo were built comprising various older systems that were disassembled from Sa'ar 4-class boats with the same names, atop brand new Sa'ar 4.5-class hulls. INS Tarshish possibly also comprised some weapon systems dismounted from the Sa'ar 4-class missile boat with the same name, atop a new Sa'ar 4.5-class hull.

Another two further-upgraded Sa'ar 4.5 Hetz-subclass missile boats called INS Herev and INS Sufa were commissioned in 2002 and 2003, raising the number of Sa'ar 4.5 Hetz-subclass missile boats to eight.

Aliya subclass
The first two Sa'ar 4.5 boats were Aliya subclass. Two boats of this version were built and launched in 1980, the first one being INS Aliya, followed by INS Geula. Additionally to the anti-ship missiles, these missile boats were equipped with aviation facilities that could accommodate two (one on a regular basis) Bell 206, MD 500, or HH-65 helicopters. Eurocopter Panther was the last helicopter deployed on these boats in the Israeli Navy. The Aliya subclass are the smallest warships with a helipad and helicopter hangar.

In August 1984, INS Aliya and INS Geula were sent to destroy a terrorist facility in Nahr al-Bared, northern Lebanon. Two MD 500 Defenders from INS Aliya and another two from INS Geula successfully hit the target. In July 1985, INS Aliya and INS Geula carried out a similar mission near Nahr al-Bared.

Hetz subclass
Sa'ar 4.5 Hetz-subclass missile boats lack the helicopter facilities of the Aliya subclass, but have more weapon systems fitted. They are largely based on the Sa'ar 4-class missile boat with improvements in electronic systems: command and control, detection, classification and identification, fire control system, radar (EL/M-2258 active electronically scanned array), sonar, electronic warfare and communications. The engines and propulsion systems were also upgraded. The boat itself is 4 m longer than the Sa'ar 4-class missile boats to accommodate the new systems.

Future replacement
Beginning in the mid-2020s, the Israeli Navy plans to replace the Sa'ar 4.5 boats with the future Reshef-class ships. These 76 m long vessels will be based on Israel Shipyards' Sa'ar 72-class corvette design. They will deploy advanced weaponry and defensive systems, including C-Dome.

Israel
As of 2019, eight Hetz-subclass boats are in service with the Israeli Navy.

Mexico
In January 2004 both INS Aliya and INS Geula were sold to Mexico for service in the Mexican Navy. On August 23, 2004 the boats were relaunched in Mexico renamed ARM Huracán and ARM Tormenta. Press reports indicate that Israel removed the Harpoon missile systems prior to the sale, however, the Gabriel anti-ship missile systems were included in the package.

Greece
The Hellenic Coast Guard bought three offshore patrol boats based on the Sa'ar 4.5 Nirit-class design, but armed only with a 30 mm gun. A crane is installed at the deck space normally reserved for missiles.