Hot Bird 7

{{Short description|Communications satellite that was lost during a launch failure in 2002}}

{{Use British English|date=April 2021}}

{{Use dmy dates|date=April 2021}}

{{Infobox spaceflight

| name = Hot Bird 7

| names_list =

| image =

| image_caption =

| image_size = 300px

| mission_type = Communications

| operator = Eutelsat

| COSPAR_ID =

| SATCAT =

| website = https://www.eutelsat.com/en/home.html

| mission_duration = 15 years (planned)
Failed to orbit

| spacecraft = Hot Bird 7

| spacecraft_type = Eurostar

| spacecraft_bus = Eurostar-2000+

| manufacturer = Astrium

| launch_mass = {{cvt|3300|kg}}

| dry_mass = {{cvt|1500|kg}}

| dimensions = 2.3 × 3.4 × 5.2 m
span: 27.9 m in orbit

| power = 7.5 kW

| launch_date = 11 December 2002, 22:22 UTC

| launch_rocket = Ariane 5ECA (V157)

| launch_site = Centre Spatial Guyanais, ELA-3

| launch_contractor = Arianespace

| entered_service =

| disposal_type =

| deactivated =

| last_contact =

| orbit_reference = Geocentric orbit (planned)

| orbit_regime = Geostationary orbit

| orbit_longitude = 13° East

| apsis = gee

| trans_band = 40 Ku-band

| trans_frequency =

| trans_bandwidth =

| trans_capacity =

| trans_coverage = Europe, North Africa, Middle East

| programme = Eutelsat constellation

| previous_mission =

| next_mission =

}}

Hot Bird 7 was a communications satellite that was lost in a launch failure in 2002. Intended for operation by Eutelsat, it was to have provided direct-to-home broadcasting services from geostationary orbit as part of Eutelsat's Hot Bird constellation at a longitude of 13° East. Hot Bird 7 was intended to replace the Hot Bird 3 satellite, which had been launched in 1997.{{cite web|url=http://www.spaceref.com/news/viewpr.html?pid=10114|archive-url=https://archive.today/20131004163014/http://www.spaceref.com/news/viewpr.html?pid=10114|url-status=dead|archive-date=4 October 2013|title=Eutelsat Statement of Launch Failure of Hot Bird 7|publisher=SpaceRef|date=11 December 2002|access-date=16 April 2021}}

Hot Bird 7 was constructed by Astrium, and was based on the Eurostar-2000+ satellite bus. It had a mass of {{cvt|3400|kg}} and was expected to have an operational lifespan of 15 years. The spacecraft was equipped with 40 Ku-band transponders,{{cite web|url=http://space.skyrocket.de/doc_sdat/hotbird-7.htm |title=Hot Bird 7|publisher=Gunter's Space Page|date=21 July 2019|access-date=16 April 2021}} for broadcasting satellite television and radio. It would have broadcast to homes in Europe, the Middle East and North Africa.

Arianespace was contracted to launch Hot Bird 7 on the maiden flight of the Ariane 5ECA launch vehicle, an upgraded version of the Ariane 5 intended to offer increased payload capacity to Geostationary transfer orbit (GTO). The STENTOR technology demonstration satellite, to have been operated by the French space agency CNES, was also aboard the launch vehicle.{{cite web|url=http://www.arianespace.com/images/launch-kits/launch-kit-pdf-eng/02_dec_11.pdf|title=First Flight of 10-ton Payload Ariane 5|publisher=Arianespace|access-date=16 April 2021 |url-status=dead|archive-url=https://web.archive.org/web/20131004221619/http://www.arianespace.com/images/launch-kits/launch-kit-pdf-eng/02_dec_11.pdf|archive-date=4 October 2013}} The launch took place from ELA-3 at Centre Spatial Guyanais, at Kourou, in French Guiana, at 22:22 UTC on 11 December 2002,{{cite web |url=http://planet4589.org/space/log/launchlog.txt|title=Launch Log|first=Jonathan|last=McDowell|work=Jonathan's Space Page|date=14 March 2021|access-date=16 April 2021}} bound for geosynchronous transfer orbit.

Around three minutes after liftoff, performance issues with the first stage's Vulcain 2 engine, which was making its first flight, were noticed. By the time of fairing separation, 183 seconds into the flight, the rocket was tumbling out of control. It began to lose altitude and speed, before being destroyed by range safety officer 456 seconds after launch.{{cite web|url=http://spaceflightnow.com/ariane/v157/status.html|title=Mission Status Center|publisher=Spaceflight Now|date=12 December 2002|access-date=4 October 2013}} The failure was attributed to an engine cooling problem that developed around 96 seconds into the mission, causing the engine to destroy itself.{{cite book|last=Harland|first=David M.|author2=Lorenz, Ralph D.|title=Space Systems Failures|publisher=Springer-Praxis|location=Chichester|year=2005|edition=2006|isbn=0-387-21519-0|page=149}} Due to the failure the next Ariane 5 launch, which had been scheduled to carry the European Space Agency's (ESA) Rosetta spacecraft in January 2003, was delayed — causing Rosetta to miss its launch window for a mission to comet 46P/Wirtanen. Rosetta was subsequently retargeted to 67P/Churyumov–Gerasimenko and launched successfully in 2004.