Ariane

by Jean-Jacques Serra
European launch vehicle program operated by Arianespace.

After the failure of the Europa 1/2 program, the ELDO was to design a totally new Europa 3. This launcher was to have a first stage L150 with stockable propellant powered by 4 Viking motors from SEP and a second cryogenic stage H20 equipped with a hight pressure HM-20 motor from Cryorocket. This project was found too risky both technically and financially especially by Germany which wanted to focus on the construction of Spacelab.

In 1972 the CNES proposed to built a launcher with the same performance but using only European tested technology like the low-pressure cryogenic propulsion. This project designed L-IIIS (substitution third generation launcher) was to use an H6 cryogenic top stage with a HM-4 motor designed by SEP. The poor performance of the H6 compared to the H20 required the use of two base stages, on L140 (reduced version of the Europa 3 L150) and an L33 (featuring a single Viking motor adapted to altitude use).

In December 1972 the 5th European Space Conference ended on 3 agreements: creation of a European Space Agency (ESA to replace both ELDO and ESRO) and the start of the L-IIIS and Spacelab.

The following year the L-IIIS project was further precised (increased propellant of the H6 to become H8 and replacement of the 4-chamber HM-4 by a single-nozzle HM-7) and changed denomination: Ariane. The CNES granted Aerospatiale as the industrial architect of the project.

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Ariane 1

The first Ariane version was a 208-ton launcher (without payload) of 47.4 m high. The first stage (L140) was 3.8 m diameter, 18.4 m high, containing 147.6 tons propellant (NTO + UDMH). It was powered by a set of 4 Viking 5 motors which fired during 146 seconds, providing 2485 kN thrust at takeoff (Isp = 247 s) and 2770 kN in vacuum (Isp = 278 s). The second stage (L33) was 2.6 m diameter for 11.6 m high. It was loaded with 34.2 tons propellant identical to first stage. It's Viking 4 motor provided 723 kN thrust (Isp = 296 s) during 138 seconds. The top stage (H8) of same diameter was 9.1 m high. It's cryogenic motor HM-7 developped 61.3 kN thrust (Isp = 441 s) and consumned 8.2 tons liquid oxygen and hydrogen in 545 seconds. The first and third stage were assembled in France by Aerospatiale, the second stage in Germany by ERNO.

Ariane was optimized for launches in GTO to which it could deliver 1750 kg.

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Ariane 2 & 3

As soon as 1977 the CNES started enhancing the performance of the launcher. The first derivatives named Ariane 2 & 3 had the following characteristics:

- On the two first stages: enhancement of the thrust of the Viking 4 and 5 by increasing the pressure of the combustion chamber and replacement of UDMH by UH25 (75% UDMH and 25% hydrazine hydrate). The combustion duration where then respectively 135 and 123 seconds.

- On the third stage: lengthening by 1.3 m of the tanks (10.7 tons propellant on this new H10) and increased specific impulsion of the motor (HM-7B). The combustion duration was then 720 s.

- Extension of the payload volume

The Ariane 3 version had also two additional solid booster: 8 m high, 1.07 m diameter, 9.7 tons (including 7.3 tons solid propellant: Flexadyne). Each booster provided 666 kN thrust during 28 s. They were manufactured by BPD in Italy.

The two launchers were 48.7 high. Ariane 2 weighed 212 tons at takeoff while Ariane 3 weighed 230 tons. The payload weights then reached 2065 kg and 2580 kg in GTO.

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Ariane 4

The construction of a series of launchers named Ariane 4 with enhanced performance was decided in 1981. Those launchers are directly derived from the previous version, retaining the 3 stages and lengthening the first one and addition solid and/or liquid boosters.

The first stage of Ariane 4 named L220 is 23.2 m high. It transports 227 tons propellant identical to Ariane 2/3. It is still powered by a set of Viking 5 motors (version C) which provide during 205 seconds 2710 kN thrust at takeoff (3010 kN in vacuum, Isp = 278 s). The two other stages are those of Ariane 2/3 with a reinforced structure. The 3rd stage has been lengthened twice giving the H10+ (11 tons propellant) and H10-3 (11.8 tons propellant) versions. The latter burns during 13 minutes.

The flexibility of Ariane 4 is due to the adaptation of the payload by addition of boosters on the first stage. Those are of 2 types: PAP (solid) and PAL (liquid). The PAPs are a enhancement of the Ariane 3 boosters. They are 12 m high, weigh 12.6 tons (including 9.5 tons powder) and provide 650 kN thrust (Isp = 224 s) during 36 seconds. The PALs are built by MBB/ERNO. They are 19 m high, 2.2 m diameter, weigh 43.5 tons (39 tons of the same propellant as the first stage). Their Viking 6 motor fires during 143 seconds and provides 678 kN at ground level, 752 kN in vacuum.

The possible configurations are:
- Ariane 40: no boosters
- Ariane 42: 2 boosters, 42P with 2 PAP and 42L with 2 PAL
- Ariane 44: 4 boosters, 44P with 4 PAP, 44L with 4 PAL, 44LP with 2 PAP and 2 PAL

The launcher's height ranges from 54.1 m to 58.4 m depending on the cap used. Its mass ranges from 243 tons (Ariane 40) to 480 tons (Ariane 44L) and the GTO performance from 2020 kg to 4460 kg. Ariane 4 should remain in active service until the end of the century.

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Ariane 5

The launch of the Ariane 5 program was decided by ESA members in November 1987 following an initial study launched in early 1985. Built with Aerospatiale as prime contractor, Ariane 5 is totally different from the previous Arianes in terms of architecture. It's configuration is closer to Titan or STS or H2. Like those launchers, Ariane 5 has got a main body with liquid propulstion and 2 large solid boosters.

The EAP (Etage d'Accélération à Poudre, acceleration solid stage) is composed of two MPS (Moteurs à Propulsion Solide, solid propulsion motors) also named P230 built by Europropulsion (a 50/50 groupement of SEP (France) and BDP (Italy)). Each MPS is 27 m high and 3 m diameter and weighs 267 tons including 237 tons of propellant (3 PBHT segments). They provide 6 MN thrust at takeoff (ISp = 273 s) and work during 123 s before being jettisonned at 56 km altitude.

The main body is made of an EPC (Etage Principal Cryotechnique, cryogenic main stage) and an ETS (Etage à Propergols Stockables, stockable propellant stage). The EPC is 30.5 m high and 5.4 m diameter. It is propulsed by a Vulcain flux-derived motor from SEP. It's thrust is 880 kN at ground level and reaches 1130 kN in vacuum (ISp = 430 s). The MPS are ignited only after the Vulcain motor has prooved to be working properly; it then burns 131 tons of LOX and 26 tons of LH2 within 600 seconds. The EPS alias L9 uses 9.7 tons of conventional ergols (NTP and MMH-H) and care for the precise orbital release. It is equipped with a MBB-ERNO (DASA group) Aestus motor of 28 kN thrust in vacuum than can work 1150 seconds and can be re-ignited.

With the equipment compartment and the cap (2 different versions are available) Ariane 5 is 45.7 to 55.9 m high. It weighs 710 tons. It's capacity to GTO is 6.8 tons with one satellite or 5.9 tons with 2 satellites or 5.5 tons with 3.

The 5GS version features an improved set of solid rocket boosters (EAP P240) and additional upper stage propellant (EPS L10).

In 2015 privatisation is boosted as Airbus Safran Launchers (ASL) is about to control 74% of the shares.

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Ariane 6

The Ariane 6 was decided in 2015 after the privatisation and control acquisition by Airbus Safran Launchers.
Two versions of the Ariane 6 are announced for 2020.
The first stage is made of P120C solid rocket boosters (4500 kN, combustion time 130 seconds). The second stage is a main cryogenic propulsion stage based on the Vulcain 2.1 engine (1350 kN of thrust, 140 t of liquid oxygen and hydrogen). The third stage is based on the Vinci cryogenic engine (180 kN of thrust, re-ignatable).

Ariane 6-2 (A62) is the two-booster version intended to lift 5000 kg to GTO and 7000 kg to sun-synchronous orbit.

Ariane 6-4 (A64) is the four-booster version intended to lift 10,000 kg to GTO. This version could be used to launch small satellites directly in GEO from 2022.

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Ariane statistics

Type	First launch	Last launch	LEO/GTO capacity (kg)	Number of launches
1	24 Dec 1979	22 Feb 1986	/ 1700	11 (2 failures)
2	30 May 1986	2 Apr 1989	/ 2065	6 (1 failure)
3	4 Aug 1984	12 Jul 1989	/ 2580	11 (1 failure)
40	22 Jan 1990	3 Dec 1999	4900 / 2020	7
42P	20 Nov 1990	4 May 2002	6100 / 2740	15 (1 failure)
44P	4 Apr 1991	25 Sep 2001	6900 / 3290	15
42L	12 May 1993	23 Jan 2002	7400 / 3350	12
44LP	15 Jun 1988	27 Nov 2001	8300 / 4030	29 (1 failure)
44L	4 Jun 1989	15 Feb 2003	9600 / 4800	38 (1 failure)
5 G	4 Jun 1996	18 Dec 2004	18000 / 6700	19 (1 failure)
5 GS	11 Aug 2005	18 Dec 2009	/ 7350	5
5 E-CA	11 Dec 2002	26 Nov 2019	/ 10000	69 (1 failure)
5 ECA+	6 Aug 2019	5 Jul 2023	/ 10500	12
5 ES	9 Mar 2008	25 Jul 2018	20050 /	8
5 ME	2017?		/ 12000

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Motor performance

Type	First launch	4 Viking 5	4 Viking 5 Thrust (kN)	4 Viking 5 Isp (s)	Viking 4	Viking 4 Thrust (kN)	Viking 4 Isp (s)	HM7	HM7 Thrust (kN)	HM7 Isp (s)
1	1979	A	2485s/2770v	247s/278v	A	723	296	-	61.3	441
2/3	1984	B	2690s/2980v		B	785	296	B	62.8	445
4	1988	C	2710s/3010v		B	-	-	B	-	-

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External resources

http://www.arianespace.com/

http://www.capcomespace.net/dossiers/espace_europeen/ariane/

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