# Simorgh (rocket)

Simorgh (Persian: ماهواره‌بر سیمرغ, Simurgh), 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.

## Design

Simorgh is a two-stage liquid-fueled rocket developed from the Safir rocket. It is able to place a 250 kg (550 lb) payload into a circular 500 km (310 mi) low Earth orbit (LEO). It is also the first Iranian rocket that can place multiple payloads into orbit (e.g., one main payload and several secondary cubesats). In comparison, the Safir was only able to place a 50 kg payload into a 250x375 km elliptic orbit.
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. The first stage also utilize a set of four vernier engines sharing a single turbopump used for attitude control and 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 similar to the two engines of Safir's second stage. These produce a total 7,000 kgf (69 kN; 15,000 lbf) of thrust.
The Simorgh's total flight time to a 500-530km orbit is between 480 and 495 seconds. The first stage burns for about 102 seconds. Stages separation takes place at an altitude of 90 km and a velocity of 2300 m/s. The fairing shroud is ejected simultaneously to the second stage engines ignition. 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 a launch pad located at the Imam Khomeini Space Center. 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.
Saman-1 is a solid-fueled orbital transfer system under development that produces 1,300 kgf (13 kN; 2,900 lbf) of thrust and will be used as an additional upper stage in future.

## Reliability

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, 97, percent success rate respectively, indicating a trend of increasing reliability in the design.

## Launch history

| Satellite(s) | Date & Time (UTC) | Launch Site | Satellite Mass | Outcome | Remarks |
| No payload | 19 April 2016 | Semnan LP-2 | N/A | Success | Sub-orbital test flight. |
| No payload | 27 July 2017 | Semnan LP-2 | 100 kg | Failure | Orbital test flight. Simorgh operated for 136 seconds. Second stage failed. |
| Payam (named "AUT-SAT" previously) | 15 January 2019 | Semnan LP-2 | 90 kg | Failure | Orbital test flight. Simorgh operated for 455 seconds. Third stage failed. |
| Zafar-1 | 9 February 2020, 15:45 | Semnan LP-2 | 113 kg | Failure | Orbital test flight. Simorgh operated for 475 seconds. Satellite reached speed of 6,500 m/s out of the 7,400 m/s required to orbit. First stage operated fully correctly. Second stage failed. |
| Unknown | 12 June 2021 | Semnan LP-2 | | 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. |
| Three research devices | 30 December 2021 | Semnan LP-2 | TBA | Failure | Orbital test flight.First time Iran launched multiple payloads in the same launch. Simorgh operated for about 600 seconds (500 seconds for the second stage). Devices didn't enter orbit; reached an altitude of 470 km and a speed of 7,350 m/s, out of the 7,600 m/s required. |
| Mahda, Keyhan-2 and Hatef-1 | 28 January 2024 | Semnan LP-2 | TBA | Success | First successful orbital launch of Simorgh, placed three satellites into a 1100 x 450 km orbit. The launch occurred just 8 days after the first successful orbital launch of Qaem 100. |
| Saman-1, Fakhr-1 and one other research satellite | 6 December 2024 | Semnan LP-2 | 300 kg | Success | The launch of the Saman-1 orbital transfer block to an altitude of 400 kilometers, along with two other payloads (including the Fakhr-1 satellite), with a total weight of 300 kilograms, breaking weight record. |

## Gallery

* Simorgh during the launch of Payam satellite on 15 January 2021
* Simorgh during launch preparations
* Simorgh in its servicing tower