Infrastructure tools to support an effective radiation oncology learning health system

Superbird-8 was in the upper position. It had a mass at liftoff of about 5,348 kilograms (11,790 lb).^[23] The satellite was supposed to launch in mid-2016, but due to overpressurization within the container during shipping to the launch site that caused significant damage, the satellite was returned to the manufacturer for repair work and additional testing, delaying the launch for almost two years.^[24] HYLAS-4 was in the lower position. It had a mass at liftoff of approximately 4,050 kilograms (8,930 lb).^[23]

It was Boeing's 56th, Intelsat's 60th and SKY Perfect JSAT's 20th spacecraft to be launched by Arianespace.^[27][28]

Azerspace-2, also known as Intelsat 38, had a liftoff mass of about 3,500 kilograms (7,700 lb).^[27] Azerbaijan’s second geostationary satellite would expand Azerspace-1's capacity while replacing Intelsat 12 from the 45° East position. It was SSL's 65th and Intelsat's 61st spacecraft to be launched by Arianespace.^[28]

The mission was planned to last 42 minutes and 17 seconds, placing both the satellites into geostationary transfer orbits with a perigee altitude of about 250 kilometres (160 mi) and apogee of 35,726 kilometres (22,199 mi) and an inclination of about 6 degrees.^[27][29]

The satellites were accommodated inside the medium version of the upper stage fairing.^[30] They were built by OHB System in Bremen, Germany, for the European Commission's Galileo programme under the supervision of the ESA.^[30] They were assigned to the constellation's orbital plane B to provide additional coverage and performance to the now complete initial constellation composed of 24 operational satellites plus two in-orbit spares, all of which having been put into orbit by Arianespace. The satellites, numbered 23, 24, 25 and 26, are named after children who won the European Commission's Galileo drawing competition: Tara, Samuel, Anna and Ellen, respectively.

The mission was planned to last 3 hours, 56 minutes and 54 seconds, placing the two pairs of satellites into their medium Earth orbit, at an altitude of about 22,922 kilometres (14,243 mi) (corresponding to a semi-major axis of 29,300 kilometres (18,200 mi), 300 kilometres (190 mi) below Galileo operational orbit) and an inclination of about 56 degrees.^[30][31]

The payloads of the flight were adapted together onto the SYLDA adapter inside the long version of the upper stage fairing.^[34] The total payload mass was approximately 10,018 kilograms (22,086 lb), including the adapters.^[35] The launch placed both satellites into geosynchronous transfer orbits with perigee altitudes of about 250 kilometres (160 mi) and apogee altitudes of approximately 35,786 kilometres (22,236 mi) at inclinations of about 3°.^[34]

Hellas Sat 4 was in the upper position, inside the SYLDA adapter. The telecommunication satellite had a liftoff mass of approximately 6,495 kilograms (14,319 lb) and was developed by Lockheed Martin Space in its facilities in Denver, Colorado and Sunnyvale, California for KACST and Hellas Sat.^[34] It was designed to operate for 15 to 23 years from the 39° East orbital position, providing telecommunications services to Europe, South Africa, and the Middle East with its Ku- and Ka-band payloads. It is Lockheed Martin's 46th spacecraft orbited by Arianespace.^[34]

GSAT-31 was in the lower position. The telecommunication satellite had a liftoff mass of 2,536 kilograms (5,591 lb). It was designed and manufactured by ISRO to operate for more than 15 years from the 48° East orbital position, providing telecommunications services with Ku-band coverage. It is ISRO's 22nd spacecraft orbited by Arianespace.^[34]

The rocket's boosters and EPC first stage were expended in under nine minutes, while the ESC-A upper stage's HM7B engines burned for 16 minutes;^[50] the EPC first stage intentionally crashed in the Gulf of Guinea, off the west coast of Africa.^[50] Following the conclusion of the burn, AT&T T-16 separated from the ESC-A at 22:11 UTC, 28 minutes after the start of the flight, followed by the Eutelsat 7C's separation six minutes later, at 22:17 UTC.^[38][47] The flight lasted 34 minutes,^[38] and placed the satellites into a geostationary transfer orbit from which they will eventually be placed into geostationary orbit through their own propulsion.^[49] Eutelsat 7C was placed at 7° east, a position which allowed the satellite to serve its intended markets in Africa, Central Asia, Europe, and the Middle East.^[51][45] Eutelsat 7C continued in-orbit testing until the end of 2019, after which it became fully operational.^[52]</ref>

Ariane flight VA248 was the 104th launch of an Ariane 5 launch vehicle, and the 71st launch of its ECA variant.^[49][53] It was also the fifth launch conducted by Arianespace in 2019.^[53]