|Function||Small-lift space launch vehicle|
|Country of origin||Iran|
|Height||26.5 m (87 ft)|
|Diameter||2.4 m (7 ft 10 in) first stage, 1.5 m (4 ft 11 in) second stage|
|Mass||87 t (192,000 lb)|
|Payload to LEO|
|Mass||350 kg (770 lb)|
|Family||derived from Safir|
|Launch sites||Semnan LP-2|
|Total launches||5 (+1 suborbital)|
|Success(es)||0 (1 suborbital)|
|First flight||19 April 2016 (suborbital)|
27 July 2017 (orbital)
|Powered by||4 × modified Shahab-3 engines + 4 verniers|
|Maximum thrust||1,590 kN (360,000 lbf)|
|Propellant||N2O4 / UDMH|
|Powered by||4 × modified R-27 Zyb vernier engines|
|Maximum thrust||70 kN (16,000 lbf)|
|Propellant||N2O4 / UDMH|
|Maximum thrust||13 kN (2,900 lbf)|
Simorgh (Persian: ماهوارهبر سیمرغ, Phoenix), also called Safir-2, is an Iranian expendable launch vehicle under development. It is the successor of the Safir, Iran's first space launch vehicle. Its mission is to carry heavier satellites into higher orbit than Safir.
The project was unveiled by Iranian President Mahmoud Ahmadinejad on 3 February 2010, as part of celebrations of the first anniversary of the launch of Omid, the first indigenously launched Iranian satellite, and was launched for the first time on 19 April 2016.
The Simorgh rocket is 26.5 metres (87 ft) long, and has a launch mass of 87 tonnes (192,000 lb). Its first stage with a diameter of 2.4 meters is powered by a cluster of four synchronized Safir-1B first-stage engines with four separate turbopumps, each of these engines generating up to 37,000 kilograms-force (360 kN; 82,000 lbf) of thrust, plus a set of four vernier engines sharing a single turbopump used for attitude control providing an additional 14,000 kgf (140 kN; 31,000 lbf). At liftoff, these engines generate a total 162,000 kgf (1,590 kN; 360,000 lbf) of thrust. The second stage with a diameter of 1.5 meters utilizes a set of four smaller engines (originally the vernier engines of the soviet R-27 Zyb) producing 7,000 kgf (69 kN; 15,000 lbf) of thrust. The third stage is a solid-fueled Saman-1 upper stage producing 1,300 kgf (13 kN; 2,900 lbf) of thrust. Enabling the Simorgh to place a 350-kilogram (770 lb) payload or one main payload and several secondary cubesats into a 500-kilometre (310 mi) low Earth orbit .
The Simorgh's total flight time to a 500-530km orbit is between 480 and 495 seconds. First stage's flight time is about 102 seconds. First stage separation takes place at an altitude of 90 km and a velocity of 2300 m/s. Simultaneously second stage engines ignite and the fairing shroud is ejected, the satellite is then accelerated to 7400 m/s and injected into its designated orbit.
In contrast to its predecessor Safir, the Simorgh is integrated and assembled vertically on the launch pad, each stage goes through manufacturing horizontally and is subsequently brought to the launch pad, where final assembly of the stages are completed with the aid of a custom designed service tower.
The development of the Simorgh has been marked with difficulties and unreliability of certain sub-systems due to the overcomplexity of its engines and turbopumps. Out of the system's first four launches (two orbital and two sub-orbital launches) there have been three failures, giving the rocket a reliability rating of twenty five percent. There were however, indications of progressive improvements to the design and reliability of the system with each successive launch; with the 2017 launch operating for 120 seconds before failure, the 2019 launch operating 450 seconds before failure, and the 2020 launch operating correctly for 475 seconds out of the 490 seconds of operation required for a successful mission, giving the missions a 25, 92, and 97 percent success rate respectively, indicating a trend of increasing reliability in the design.
|Flight No.||Date & Time (UTC)||Payload||Outcome||Type||Remarks|
|1||19 April 2016||No Payload||Success||Sub-orbital test flight|
|2||27 July 2017||Tolou||Failure||Orbital test flight||Simorgh operated for 136 seconds. Second stage failed.|
|3||15 January 2019||Payam (named "AUT-SAT" previously)||Failure||Orbital test flight||Simorgh operated for 455 seconds. Third stage failed.|
|4||9 February 2020
|Zafar-1||Failure||Orbital test flight||Simorgh operated for 475 seconds. Satellite failed to reach orbit; reached speed of 6,500 m/s out of the 7,400 m/s required. First stage operated fully correctly.|
|5?||12 June 2021||Unknown||Disputed launch existence||U.S. official stated "is aware of an Iranian rocket launch failure". Satellite imagery "looked like a launch" occurred. Iran's Telecommunications Minister denied any launch.|
|6||30 December 2021||Three research devices||Failure||Orbital test flight||First time Iran launches three cargos at the same time.|