A Russian Soyuz-U booster has staged what is expected to be its final non-Progress mission, with a rousing liftoff from Site 31/6 at Baikonur Cosmodrome in Kazakhstan. The vehicle—a direct descendent of Chief Designer Sergei Korolev’s R-7 “Semyorka” (“Little Seven”) intercontinental ballistic missile, developed in the 1950s—roared into the night sky at 10:20 p.m. local time (12:20 p.m. EDT) Wednesday. Within nine minutes, it had successfully inserted Egypt’s second remote-sensing satellite, known as “EgyptSat-2,” into a circular orbit of 435 x 435 miles (700 x 700 km), inclined 51.6 degrees to the equator. EgyptSat-2 should remain in service for up to 11 years, providing unprecedented visible and multispectral imagery of the territory of Egypt and its environs.
As described in yesterday’s AmericaSpace preview article, the Soyuz-U booster was transferred in a horizontal configuration to the launch pad on Monday, 14 April. Following receipt of standard authorization, the vehicle’s core and upper stages and its four tapering strap-on boosters were fueled with a mixture of liquid oxygen and a rocket-grade form of kerosene, known as “RP-1.” Their task complete, the propellant cars departed the launch complex at about 9 p.m. local time (11 a.m. EDT). Despite a brief disruption to the live televised feed from Baikonur, the service tower had retracted from around the Soyuz-U by 9:55 p.m. local time (11:55 a.m. EDT) and all personnel had been cleared from the pad to safe limits beyond the anticipated blast zone.
In the final minutes of today’s countdown, the rocket’s flight computers were uploaded with their updated trajectory plans, and at 10:12 p.m. local time (12:12 p.m. EDT) the EgyptSat-2 payload was transferred from pad utilities to internal power. Its on-board batteries would provide power until it achieved orbit and deployed its trio of electricity-generating solar arrays. At T-6 minutes, the booster entered its automated countdown sequence, and about 60 seconds later the “launch key”—an actual, physical key which enables the ordnance systems and permits the launch to go ahead—was inserted under the direction of the Launch Director in the command bunker. The engines of the first stage were purged with nitrogen, and cryogenics were topped off for the final time. At T-10 seconds, the turbopumps on the central core and the four tapering boosters awakened and the engines steadily built up thrust to full power, producing a retraction of the fueling tower and a spectacular, on-time liftoff into the darkened Baikonur sky at 10:20 p.m. local time (12:20 p.m. EDT).
Rising rapidly, the vehicle exceeded 1,100 mph (1,770 km/h) within a minute of launch, and at T+118 seconds, at an altitude of 28 miles (45 km), the four strap-on boosters exhausted their propellant and were jettisoned. This left the central core and its single RD-118 engine to continue the push into orbit. By two minutes into the flight, the Soyuz-U was already traveling at more than 3,350 mph (5,390 km/h). The payload shroud was discarded shortly thereafter, and, four minutes and 45 seconds after leaving Baikonur, the core stage separated at an altitude of 105 miles (170 km). The single RD-0110 engine of the final stage then roared to life to boost EgyptSat-2 into orbit. Due to the fact that the satellite is far lighter than Russia’s Progress cargo vehicles, it was noted by Spaceflight101 that this launch would feature a “direct ascent” into the 435-mile (700 km) planned altitude, after which the vehicle executed a “pitch-down” maneuver for circularization. Shutdown of the final stage, according to AmericaSpace’s Launch Tracker, came crisply at 10:28:45 p.m. local time (12:28:45 p.m. EDT). Less than nine minutes had elapsed since the Soyuz-U had left Baikonur and Egypt’s new remote-sensing satellite was safely in orbit.
Today’s launch will come as something of a relief for Egypt’s National Authority for Remote Sensing and Space Sciences (NARSS), which achieved considerable success with its EgyptSat-1 mission. Launched atop a Dnepr rocket from Baikonur in April 2007, EgyptSat-1—also known as “MisrSat-1″—operated without incident for more than three years, returning 5,000 images with a ground resolution of about 25.6 feet (7.8 meters). Unfortunately, in July 2010, a failure of its S-band communications system brought a premature end to the mission. As a direct result of this failure, in 2011 it was decided to place EgyptSat-2 on hold as the investigative process got underway. At length, the second mission was tentatively scheduled for launch in 2013, but this target was postponed several times. By the time the 2,300-pound (1,050-kg) satellite finally arrived at Baikonur in February 2014, processing of the Soyuz-U was already well advanced. Over the following weeks, EgyptSat-2 underwent extensive testing and was integrated into its payload shroud. On Monday, 14 April, atop the Soyuz-U, it was rolled horizontally from the assembly building to Site 31/6, where the vehicle was raised to a vertical orientation.
EgyptSat-2 is a hexagonal satellite, equipped with three deployable, fixed solar arrays, together with nickel-hydrogen batteries, and is expected to remain operational for approximately 11 years. Its optical imaging payload will cover the visible and infrared spectral bands, providing a ground resolution of 13.1 feet (four meters) for multispectral imagery and 3.3 feet (one meter) for panchromatic imagery. Key objectives include total coverage of Egypt’s land and maritime territory and their environs for the purposes of mapping, environmental monitoring, and disaster management. Data will be transmitted through an X-band communications terminal at a rate of 300-600 Mbits/sec to ground stations located near Cairo in the north of Egypt and Aswan in the south. Another satellite, DesertSat, with a spatial resolution of 8 feet (2.5 meters) and a specific focus upon desert resources, is scheduled for launch in 2017.