Intelsat 35e, also known as IS-35e is an

Intelsat Intelsat S.A. (formerly Intel-Sat, Intelsat) is a Luxembourgish-American multinational satellite services provider with corporate headquarters in Luxembourg and administrative headquarters in Tysons, Virginia, United States. Originally formed ...

high-throughput (HTS)

geostationary A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitud ...

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a Transponder (satellite communications), transponder; it creates a communication channel between a source transmitter and a Rad ...

designed and manufactured by

Boeing Satellite Systems The Boeing Satellite Development Center is a major business unit of Boeing Defense, Space & Security. It brought together Boeing satellite operations with that of GM Hughes Electronics' Space and Communications division in El Segundo, Califo ...

on the Boeing-702MP

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are less customized than specially-produced satelli ...

. It was launched on 5 July 2017. It is the fourth satellite of the Epic^NG service and covers the

Americas The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

and

Sub-Saharan Africa Sub-Saharan Africa is the area and regions of the continent of Africa that lie south of the Sahara. These include Central Africa, East Africa, Southern Africa, and West Africa. Geopolitically, in addition to the list of sovereign states and ...

from the 34.5° West longitude. It has a mixed C-band and

Ku-band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally ), because it is the lower part of the original NATO K band ...

, with the C-band featuring Epic^NG spot beams.

Satellite description

Intelsat 35e was designed and manufactured by Boeing Satellite Systems on the Boeing 702MP satellite bus. It had a launch mass of , the largest Intelsat's currently active satellite, and has a design life of more than 15 years. It is powered by two wings, with four

solar panels A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that produce excited electrons when exposed to light. These electrons flow through a circuit and produce direct ...

each, of triple-junction

GaAs Gallium arsenide (GaAs) is a III-V direct band gap semiconductor with a zinc blende crystal structure. Gallium arsenide is used in the manufacture of devices such as microwave frequency integrated circuits, monolithic microwave integrated circui ...

solar cells. The 702MP platform was designed to generate between 6 and 12 kW. Its payload was the fourth high-throughput Epic^NG deployment. The Epic^NG is characterized by the implementation of frequency reuse due to a mix of frequency and polarization in small-spot beams. Not only applied to the classical HTS

Ka-band The Ka band (pronounced as either "kay-ay band" or "ka band") is a portion of the microwave part of the electromagnetic spectrum. The designation "Ka-band" is from Kurz-above, which stems from the German word ''kurz,'' meaning "short". There ...

, but also applying the same technique in Ku-band and C-band. The Epic^NG series also keep the use of wide beams to offer high throughput and broadcast capabilities in the same satellite. In the case of Intelsat 35e, the C-band side has Epic^NG spot beams with a total downlink bandwidth of 4,356 MHz. The spot beams offer high bandwidth for Europe, Sub-Sahara Africa, and the Americas. The Ku-band has 39 transponder equivalents for a total downlink bandwidth of 1,404 MHz. Of the Ku-band three wide beams, one is covering the

Caribbean The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America ...

, another Europe and the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

, and the third beams cover Europe and

North Africa North Africa (sometimes Northern Africa) is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region. However, it is sometimes defined as stretching from the Atlantic shores of t ...

History

In July 2009,

became the first customer of the Boeing 702MP satellite bus, when it placed an order for four spacecraft to be built, Intelsat 21, Intelsat 22, Intelsat 27 and the first Epic^NG satellite, Intelsat 29e. In May 2013, Intelsat contracted for an additional four Epic^NG satellites, the first of which would be

Intelsat 33e Intelsat 33e, also known as IS-33e, was a high throughput (HTS) geostationary communications satellite operated by Intelsat and designed and manufactured by Boeing Space Systems on the BSS 702MP satellite bus. It was the second satellite of ...

. On 8 July 2014, Boeing announced a ninth 702MP order, and sixth EpicNG, for the Intelsat 35e. During 2014, Intelsat announced to service contract where the clients would start using

Intelsat 903 Intelsat 903 (or IS-903) is a communications satellite operated by Intelsat. Launch Intelsat 903 was launched by a Proton-K rocket from Baikonur Cosmodrome, Kazakhstan, at 22:27 UTC on March 30, 2002. Capacity and coverage The 4.7 tonne (wi ...

at the 34.5° West position and then seamlessly transfer their services to Intelsat 35e as soon as it was commissioned into service.

Launch history

Following two aborted launch attempts earlier in July 2017, Intelsat 35e was launched on 5 July 2017 from the SpaceX-leased launch pad 39A (LC-39A) in

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

. No attempt to recover the first-stage booster was made on this launch, as the first stage was flown in expendable mode in order to maximize the

orbital energy In the gravitational two-body problem, the specific orbital energy \varepsilon (or specific ''vis-viva'' energy) of two orbiting bodies is the constant quotient of their mechanical energy (the sum of their mutual potential energy, \varepsilon_p ...

imparted to this high-mass

. During an interview with Intelsat's CEO Stephen Spengler in February 2016, it was disclosed that Intelsat 35e was expected to launch in 2017. In August 2016, it emerged that the launch was assigned to a

Falcon 9 Full Thrust Falcon 9 Full Thrust (also known as Falcon 9 v1.2) is a Reusable launch system#Partial reusable launch systems, partially reusable, two-stage-to-orbit, medium-lift launch vehicle when reused and Heavy-lift launch vehicle when expended designed an ...

mission scheduled for the first quarter of 2017. Performance improvements of the

Falcon 9 Falcon 9 is a Reusable launch system#Partial reusable launch systems, partially reusable, two-stage-to-orbit, medium-lift launch vehicle designed and manufactured in the United States by SpaceX. The first Falcon 9 launch was on June 4, 2010, an ...

vehicle family enable the launch of this 6-tonne satellite without upgrading to a Falcon Heavy variant. Intelsat 35e was initially prepared for launch on 2 July 2017 from launch pad 39A, with a 59-minute-duration

launch window In the context of spaceflight, launch period is the collection of days, and launch window is the time period on a given day, during which a particular rocket A rocket (from , and so named for its shape) is a vehicle that uses jet propulsio ...

. The first launch attempt was aborted at T-9 seconds in the countdown for a GNC-criteria violation. With insufficient time to recycle, the launch was scrubbed and next attempt was scheduled with a 24-hour delay. This second launch attempt was made on 3 July 2017, and it too was aborted by the onboard computers at the same T minus 9 seconds in the countdown. Having already been pushed to the end of the launch window with no time to recycle, this resulted in a scrub for the second consecutive day. Intelsat 35e could have been rescheduled for a 4 July 2017 launch. However, in the event, the 4 July 2017 launch was postponed — per SpaceX, "out of an abundance of caution" — prior to loading propellants. A complete check of the systems both on the rocket and on the pad was performed. Intelsat 35e was successfully launched and placed in

orbit In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...

on 5 July 2017.

References

{{Orbital launches in 2017 Communications satellites in geostationary orbit Satellites using the BSS-702 bus Intelsat satellites SpaceX commercial payloads Spacecraft launched in 2017