Editing Ariane 4 (section)

== Design ==
The Ariane 4 was the ultimate development from the preceding members of the [[Ariane (rocket family)|Ariane rocket family]]. Compared with the [[Ariane 2]] and [[Ariane 3]], the Ariane 4 featured a stretched first (by 61%) and third stages, a strengthened structure, new propulsion bay layouts, new avionics, and the SPELDA (''Structure Porteuse Externe de Lancement Double Ariane'') dual-payload carrier. The basic 40 version did not employ any strap-on motors, while the Ariane 42L, 44L, 42P, 44P, and 44LP variants all used various combinations of [[solid rocket booster|solid]] and [[Liquid rocket booster|liquid]] [[strap-on booster|boosters]]. Originally designed to place {{cvt|2000|to|4200|kg|lb}} payloads in [[geostationary orbit]], the six Ariane 4 variants, aided by strap-on boosters, enabled the launch of payloads in excess of {{cvt|4900|kg|lb}} on several occasions. The Ariane 4 launcher reduced the launch costs per kilo by 55% in comparison to the original [[Ariane 1]].<ref name="harvey-2003" />{{rp|page=180}}

The rocket was used in a number of variants - it could be fitted with two or four additional [[solid rocket booster|solid]] (PAP for ''Propulseurs d'Appoint à Poudre'') or [[Liquid rocket booster|liquid]] fueled booster rockets (PAL for ''Propulseurs d'Appoint à Liquide''). The launcher included a satellite payload carrier system called ''SPELDA'' (''Structure porteuse externe de lancement double Ariane'', French for ''External Carrying Structure for Ariane Double Launches'') for launching more than one satellite at a time. The rocket captured nearly 60% of the world's commercial launch services market, serving both European and international clients.<ref>{{Cite web |date=9 June 2015 |title=Ariane 4, un défi pour l'Europe spatiale |trans-title=Ariane 4 - A challenge for Europe's space industry |url=https://ariane.cnes.fr/fr/web/CNES-fr/308-ariane-4-un-defi.php |url-status=live |archive-url=https://web.archive.org/web/20230923063802/https://ariane.cnes.fr/fr/web/CNES-fr/308-ariane-4-un-defi.php |archive-date=23 September 2023 |access-date=13 June 2015 |publisher=[[CNES]] |language=fr }}</ref> Atop the third stage was a vehicle equipment stage which housed a computer that performed various functions, including sequencing, guidance, control, tracking, [[telemetry]] and an explosive-based self-destruct.<ref name="harvey-2003" />{{rp|page=180}}

The Ariane 4 AR 40 was the basic version, with three stages: {{cvt|58.4|m|ft}} high, a diameter of {{cvt|3.8|m|ft}}, a liftoff mass of {{cvt|245000|kg|lb}} and a maximum payload of {{cvt|2100|kg|lb}} to GTO or {{cvt|5000|kg|lb}} to [[low Earth orbit]] (LEO). Main power was provided by four [[Viking (rocket engine)|Viking 2B motors]], each producing {{cvt|667|kN|lbf}} of thrust. The second stage was powered by a single Viking 4B motor, and the third stage was equipped with an [[HM7-B]] liquid oxygen/liquid hydrogen motor. The Ariane 4 AR 44L, which was outfitted with the maximum additional boost of four liquid fuel rocket strap-ons, was a four-stage rocket, weighing {{cvt|470000|kg|lb}} and capable of transferring a payload of {{cvt|4730|kg|lb}} to GTO, or alternatively {{cvt|7600|kg|lb}} to LEO.

[[File:Ariane4.gif|thumb|upright=2.0|center|5 of the 6 versions of Ariane 4]]

{| class="wikitable" style="margin:1em auto 1em auto; text-align:center;"
! Model
! PAL
! PAP
! Payload to [[Geostationary transfer orbit|GTO]] (kg)
! Launches
! Successes
! Failure date
|-----
| style="text-align:left;" | AR 40
| 0 || 0 || 2100 || 7 || 7
| 
|-----
| style="text-align:left;" | AR 42P
| 0 || 2 || 2930 || 15 || 14
| 1 December 1994
|-----
| style="text-align:left;" | AR 42L
| 2 || 0 || 3480 || 13 || 13
| 
|-----
| style="text-align:left;" | AR 44P
| 0 || 4 || 3460 || 15 || 15
| 
|-----
| style="text-align:left;" | AR 44LP
| 2 || 2 || 4220 || 26 || 25
| 24 January 1994
|-----
| style="text-align:left;" | AR 44L
| 4 || 0 || 4720 || 40 || 39
| 22 February 1990
|}