June 29, 2017

Timeline for Ariane 5’s launch of Sky Brasil 1 and Telkom 3S

A commercial satellite to broadcast television programming to millions of homes in Brazil and a multipurpose communications craft to beam high-definition video and Internet signals across Indonesia are awaiting a half-hour ride into orbit on an Ariane 5 rocket Tuesday.

Standing nearly 180 feet (55 meters) tall, the Ariane 5 is scheduled to lift off from Kourou, French Guiana, at 2139 GMT (4:39 p.m. EST; 6:39 p.m. French Guiana time) Tuesday. The launch will mark the 91st Ariane 5 flight since 1996, and the launcher’s first mission this year.

The Sky Brasil 1 satellite, built by Airbus Defense and Space and weighing more than 13,000 pounds (6 metric tons) at launch, is the heavier of the two spacecraft aboard the Ariane 5 rocket. Telkom 3S, manufactured by Thales Alenia Space, weighs 7,826 pounds (3,550 kilograms) with its propellant tanks full.

The rocket will target an orbit ranging from 155 miles (250 kilometers) to 22,205 miles (35,736 kilometers), with a tilt of 4 degrees to the equator.

Read our full story for details.

Date source: Arianespace

T-0:00:00: Vulcain 2 ignition

The Ariane 5's first stage Vulcain 2 main engine ignites as the countdown clock hits zero, throttling up to about 300,000 pounds of thrust and undergoing a computer health check before liftoff.
The Ariane 5’s first stage Vulcain 2 main engine ignites as the countdown clock hits zero, throttling up to about 300,000 pounds of thrust and undergoing a computer health check before liftoff.

T+0:00:07: Solid rocket booster ignition and liftoff

The Ariane 5's two solid rocket boosters ignite seven seconds later, each generating more than 1.3 million pounds of thrust.
The Ariane 5’s two solid rocket boosters ignite seven seconds later, each generating more than 1.3 million pounds of thrust, to push the vehicle into the sky from the ELA-3 launch pad.

T+0:00:50: Mach 1

The Ariane 5 rocket surpasses the speed of sound, heading east over the Atlantic Ocean.
The Ariane 5 rocket surpasses the speed of sound, heading east over the Atlantic Ocean.

T+0:02:20: Solid rocket boosters jettisoned

After each consuming 240 metric tons, or about 530,000 pounds, of pre-packed propellant, the solid rocket boosters are jettisoned.
After each consuming 240 metric tons, or about 530,000 pounds, of pre-packed propellant, the solid rocket boosters are jettisoned.

T+0:03:21: Payload fairing jettisoned

The Ariane 5's payload fairing, made in Switzerland by Ruag Space, releases in a clamshell-like fashion once the rocket flies above the denser, lower layers of Earth's atmosphere.
The Ariane 5’s 17.7-foot-diameter (5.4-meter) payload fairing, made in Switzerland by Ruag Space, releases in a clamshell-like fashion once the rocket flies above the denser, lower layers of Earth’s atmosphere.

T+0:08:55: Vulcain 2 shutdown

The Ariane 5’s core stage Vulcain 2 main engine shuts down after consuming 175 metric tons (385,000 pounds) of cryogenic liquid hydrogen and liquid oxygen propellants.

T+0:09:01: Stage separation

The Ariane 5’s first and second stages separate. The 98-foot-long (30-meter) first stage will fall into the Atlantic Ocean near the Gulf of Guinea off the west coast of Africa.

T+0:09:05: HM7B ignition

The Ariane 5’s upper stage HM7B engine ignites for a 16-minute, 11-second burn to place the Sky Brasil 1 and Telkom 3S satellites into geostationary transfer orbit. The HM7B engine burns liquid hydrogen and liquid oxygen, and generates more than 14,000 pounds of thrust.

T+0:25:16: HM7B shutdown

The HM7B engine shuts down after placing the Sky Brasil 1 and Telkom 3S satellites into geostationary transfer orbit with a low point of 155 miles (250 kilometers), a high point of 22,205 miles (35,736 kilometers), and an inclination of 4 degrees to the equator.

T+0:27:25: Sky Brasil 1 separation

The Sky Brasil 1/Intelsat 32e satellite, riding in the upper position on the Ariane 5’s dual-payload stack, deploys to begin a 19-year mission broadcasting television programming over Brazil and broadband Internet services to airplanes and ships transiting the Atlantic Ocean.

T+0:29:16: Sylda 5 separation

The Sylda 5 dual-payload adapter structure jettisons from the Ariane 5 upper stage, revealing the Telkom 3S spacecraft for deployment.

T+0:39:43: Telkom 3S separation

The Telkom 3S satellite separates from the Ariane 5’s upper stage to begin an 18-year mission for Telkom Indonesia.

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