The Atlas V Rocket for Boeing’s CST-100 Starliner Launch

United Launch Alliance’s Atlas V rocket that will launch Boeing’s CST-100 Starliner to the International Space Station for NASA’s Commercial Crew Program was modified specifically for the agency’s Orbital Flight Test-2. This rocket configuration does not include a payload fairing. Instead, the Starliner’s own protective surfaces will take the place of the fairing to protect the uncrewed spacecraft during launch and ascent. The rocket has two solid rocket boosters (SRBs) and a dual-engine Centaur upper stage. Starliner is attached to the Atlas V using a launch vehicle adapter, which includes an aeroskirt to reduce the aerodynamic loads on the vehicle.

The Atlas V booster is 12.5 feet in diameter and 106.5 feet in length. The booster’s propulsion is provided by the RD-180 engine system, which delivers 860,200 pounds of thrust at sea level. The SRBs generate the additional power required at liftoff, with each providing 348,500 pounds of thrust.

The Centaur second stage is 10 feet in diameter and 41.5 feet in length. For this configuration, the Centaur is configured with dual RL10A-4-2 engines, each producing 22,600 pounds of thrust. The cryogenic tanks are insulated with a combination of helium-purge blankets, radiation shields, and spray-on foam insulation. The Centaur includes an Emergency Detection System that monitors for critical hazards. This system will provide critical in-flight data which supports jettison of the ascent cover and initiates CST-100 spacecraft separation.

Learn more at www.ulalaunch.com.

Boeing’s CST-100 Starliner Spacecraft

The crew access arm is seen as it swings into position for Boeing’s CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket at the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 mission, Wednesday, May 18, 2022 at Cape Canaveral Space Force Station in Florida.
The crew access arm is seen as it swings into position for Boeing’s CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket at the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 mission, Wednesday, May 18, 2022 at Cape Canaveral Space Force Station in Florida. Photo Credit: NASA/Joel Kowsky

NASA’s Boeing Orbital Flight Test-2 will provide valuable data that will help the agency certify the company’s CST-100 Starliner spacecraft to carry astronauts to and from the International Space Station for NASA’s Commercial Crew Program. Starliner is designed to accommodate up to seven passengers or a mix of crew and cargo, but for NASA missions will carry up to four astronauts to the orbiting laboratory.

Starliner’s two main segments are the crew module and service module and together they are 16.5 feet high and 15 feet in diameter. The crew module is intended to be reused for up to 10 missions.

For orbital maneuvering and attitude control of Starliner, a total of 20 engines can each produce 1,400 pounds of thrust and, together, provide the spacecraft with the propulsion it needs to reach orbit after separating from United Launch Alliance’s Atlas V rocket. A combined 28 reaction control system engines, each providing 85 pounds of thrust, will provide the velocity needed for Starliner to make small directional changes, including when it docks to the space station. The spacecraft also is equipped with four launch abort engines to be used during an unlikely abort scenario.

Starliner is designed to land at one of five landing sites in the continental U.S. Learn more at www.boeing.com/Starliner.

Boeing’s Orbital Flight Test-2 Objectives

On May 18, 2022, Boeing’s CST-100 Starliner spacecraft and the United Launch Alliance Atlas V rocket rolled out from the Vertical Integration Facility to the launch pad at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida.
On May 18, 2022, Boeing’s CST-100 Starliner spacecraft and the United Launch Alliance Atlas V rocket rolled out from the Vertical Integration Facility to the launch pad at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida. Photo credit: NASA/Kim Shiflett

NASA’s Boeing Orbital Flight Test-2 will test the end-to-end capabilities of the company’s CST-100 Starliner spacecraft from launch to docking to a return to Earth in the desert of the western United States. The flight test will provide valuable data toward NASA certifying Boeing’s crew transportation system for regular crewed flights to and from the International Space Station. OFT-2 will build on the objectives achieved during Starliner’s initial flight test, including:

  • In-orbit operation of the avionics, docking system, communications and telemetry systems, environmental control systems, solar arrays and electrical power systems and propulsion systems;
  • Performance of the guidance, navigation and control systems of the Starliner and Atlas V through ascent, on-orbit, and entry;
  • Acoustic and vibration levels, and loads across the Starliner exterior and interior;
  • Launch escape trigger monitoring; and
  • Performance of the Starliner system end-to-end mission operations.

These objectives are intended to demonstrate all of Starliner’s systems and capabilities except for those requiring a human onboard to test.

For this flight, Starliner will carry more than 500 pounds of NASA cargo and crew supplies to the space station. After a successful docking, the spacecraft will spend five to 10 days aboard the orbiting laboratory before returning to Earth. The spacecraft will return with nearly 600 pounds of NASA cargo, including reusable Nitrogen Oxygen Recharge System tanks that provide breathable air to station crew members.

Read more about OFT-2.

Live Coverage Begins for NASA and Boeing’s Orbital Flight Test-2

A United Launch Alliance Atlas V rocket with Boeing’s CST-100 Starliner spacecraft aboard is seen after being rolled out of the Vertical Integration Facility to the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 (OFT-2) mission, Wednesday, May 18, 2022 at Cape Canaveral Space Force Station in Florida.
A United Launch Alliance Atlas V rocket with Boeing’s CST-100 Starliner spacecraft aboard is seen after being rolled out of the Vertical Integration Facility to the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 (OFT-2) mission, Wednesday, May 18, 2022 at Cape Canaveral Space Force Station in Florida. Photo Credit: NASA/Joel Kowsky

Good afternoon from Kennedy Space Center in Florida, and welcome to live launch coverage of NASA’s Boeing Orbital Flight Test-2 (OFT-2) to the International Space Station, launching in a little over an hour. Boeing’s CST-100 Starliner spacecraft sits atop a United Launch Alliance Atlas V rocket poised on the launch pad ready to go at nearby Space Launch Complex-41 on Cape Canaveral Space Force Station.

OFT-2 is an uncrewed flight test of the company’s Starliner spacecraft for NASA’s Commercial Crew Program. Liftoff is scheduled for 6:54 p.m. EDT during an instantaneous launch window.

The countdown is currently proceeding according to schedule. Fueling of the Atlas V rocket began a little after noon EDT today. The first stage booster’s RD-180 engine, containing two thrust chambers, was fueled with Rocket Propellant-1, a highly purified kerosene. The Centaur second stage was fueled with liquid hydrogen and liquid oxygen. Fueling of the rocket was completed about two hours later.

Stay with us here for coverage as the countdown continues towards launch. Watch the coverage live on NASA TV starting at 6 p.m. EDT. More details about the flight test and NASA’s Commercial Crew Program can be found in the online press kit and by following the @commercial_crew on Twitter and commercial crew on Facebook.

Meteorologists with the U.S. Air Force 45th Weather Squadron continue to predict an 80% chance of favorable weather for launch this afternoon. The primary concerns for launch day are the cumulus and anvil cloud rules violations during the instantaneous launch window.

Orbital Flight Test-2 Starliner, Atlas V Roll to Pad, NASA Leaders to Brief Media

On May 18, 2022, Boeing’s CST-100 Starliner spacecraft and the United Launch Alliance Atlas V rocket roll out from the Vertical Integration Facility to the launch pad at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida.
On May 18, 2022, Boeing’s CST-100 Starliner spacecraft and the United Launch Alliance Atlas V rocket roll out from the Vertical Integration Facility to the launch pad at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida. Photo credit: NASA/Kim Shiflett

This morning, Wednesday, May 18, Boeing’s CST-100 Starliner spacecraft and the United Launch Alliance (ULA) Atlas V rocket rolled out of the ULA Vertical Integration Facility to the launch pad at Space Launch Complex-41 on Cape Canaveral Space Force Station in Florida ahead of the uncrewed launch of NASA’s Boeing Orbital Flight Test-2 (OFT-2) to the International Space Station. Liftoff is scheduled for 6:54 p.m. EDT on Thursday, May 19.

For a launch Thursday, meteorologists with the U.S. Space Force 45th Weather Squadron continue to predict a 70% chance of favorable weather. The primary weather concerns for launch day are the cumulus and anvil cloud rules violations during the instantaneous launch window.

NASA leaders will update members of the news media on OFT-2 during a briefing on Wednesday, May 18, at 1 p.m. The briefing will air live on NASA TV, the NASA app, and the agency’s website. Participants include:

  • Bob Cabana, NASA associate administrator
  • Janet Petro, director, NASA’s Kennedy Space Center
  • Kathryn Lueders, associate administrator, Space Operations Mission Directorate at NASA
  • NASA astronaut Suni Williams
  • NASA astronaut Butch Wilmore
  • NASA astronaut Mike Fincke

NASA TV will cover the upcoming prelaunch, launch, and docking activities. Mission coverage is as follows (all times Eastern):

Thursday, May 19

6 p.m. – NASA TV launch coverage begins for a targeted 6:54 p.m. liftoff. NASA TV will have continuous coverage through Starliner orbital insertion.

9 p.m. (approximately) – Postlaunch news conference on NASA TV

Friday, May 20

3:30 p.m. – NASA TV rendezvous and docking coverage begins.

7:10 p.m. (approximately) – Docking

Friday, May 21

11:30 a.m. – NASA TV hatch opening coverage begins

11:45 a.m. – (approximately) Hatch opening and welcoming remarks

Learn more about station activities by following @space_station and @ISS_Research on Twitter as well as the ISS Facebook and ISS Instagram accounts.

Starliner Joins Atlas V at Space Launch Complex-41

Boeing's CST-100 Starliner
Boeing’s CST-100 Starliner spacecraft rolls out from the company’s Commercial Crew and Cargo Processing Facility at NASA’s Kennedy Space Center in Florida on May 4, 2022, on its way to Space Launch Complex-41 at Cape Canaveral Space Force Station. Photo credit: NASA/Glenn Benson

On Wednesday, May 4, Boeing’s CST-100 Starliner was joined with the rocket that will launch the spacecraft on its way to the International Space Station on an uncrewed flight test for NASA’s Commercial Crew Program.

During the operation, Starliner rolled out of the Commercial Crew and Cargo Processing Facility (C3PF) at NASA’s Kennedy Space Center in Florida and made its way to Space Launch Complex-41 (SLC-41) at Cape Canaveral Space Force Station in preparation for the company’s second uncrewed Orbital Flight Test (OFT-2)

CST-100 Starliner and Atlas V rocket
United Launch Alliance’s Atlas V rocket and Boeing’s CST-100 Starliner spacecraft are fully assembled in preparation for an integrated systems test. Photo credit: United Launch Alliance

Starliner was raised and carefully placed onto the rocket and now is fully assembled and ready for an integrated systems test, a tip-to-tail electrical check of the 172-foot-tall Atlas V and Starliner stack.

OFT-2 is scheduled to launch Thursday, May 19, to demonstrate the system’s human transportation capabilities.

About 24 hours after launch, Starliner will rendezvous and dock to the space station and then return to Earth five to 10 days later. The test is the last flight before the Starliner system launches American astronauts on the Crew Flight Test (CFT) to the microgravity laboratory – the spacecraft’s first flight test with crew on board. Potential launch windows for CFT are under review and will be determined after a safe and successful OFT-2.

More details about the mission and NASA’s commercial crew program can be found by following the commercial crew blog@commercial_crew on Twitter, and commercial crew on Facebook.

NASA, Boeing Continue to Work Toward Understanding Starliner Service Module Valve Performance Issue

NASA Boeing OFT-2 Starliner spacecraft
On July 29, 2021, Boeing’s CST-100 Starliner spacecraft is shown on top of the United Launch Alliance (ULA) Atlas V rocket in ULA’s Vertical Integration Facility.

NASA continues to work side-by-side with Boeing to understanding the CST-100 Starliner’s service module valve performance, including the unexpected indications some of the valves were in the closed position during its Aug. 3 launch attempt of Orbital Flight Test-2 (OFT-2).

With troubleshooting ongoing in the United Launch Alliance Vertical Integration Facility at NASA’s Kennedy Space Center in Florida, where Starliner will be powered and run through various procedures to help understand the issue, NASA will move forward with the launch and berthing of an important cargo mission to the International Space Station.

Northrop Grumman’s Cygnus spacecraft is scheduled to launch on the company’s Antares rocket at 5:56 p.m. Tuesday, Aug. 10, from NASA’s Wallops Flight Facility in Wallops Island, Virginia, with capture and berthing scheduled two days later at about 6:10 a.m. EDT Thursday, Aug. 12.

In parallel, managers and engineers with NASA and Boeing will continue to evaluate schedules based on where the troubleshooting efforts take them before deciding when the next official launch for the OFT-2 mission will take place.

Boeing Starliner Orbital Flight Test Update

A two-stage United Launch Alliance Atlas V rocket lifts off from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida for Boeing’s Orbital Flight Test, Dec. 20, 2019. Liftoff occurred at 6:36 a.m. EST. The uncrewed Orbital Flight Test is the Starliner’s first flight to the International Space Station for NASA’s Commercial Crew Program.
A two-stage United Launch Alliance Atlas V rocket lifts off from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida for Boeing’s Orbital Flight Test, Dec. 20, 2019. Liftoff occurred at 6:36 a.m. EST. The uncrewed Orbital Flight Test is the Starliner’s first flight to the International Space Station for NASA’s Commercial Crew Program. Photo credit: NASA/Glenn Benson

After a successful launch at 6:36 a.m. EST Friday on the ULA Atlas V rocket from Space Launch Complex 41 at Cape Canaveral Air Force Station, Boeing’s CST-100 Starliner is an unplanned, but stable orbit. The team is assessing what test objectives can be achieved before a safe return of the spacecraft to land in White Sands, New Mexico. NASA and Boeing officials held a post-launch news conference Friday morning.

Atlas V and Boeing CST-100 Starliner Ready for Launch

A United Launch Alliance Atlas V rocket, topped by Boeing's CST-100 Starliner spacecraft, stands on the launch pad at Space Launch Complex 41 at Florida's Cape Canaveral Air Force Station, Dec. 18, 2019, after rolling from the Vertical Integration Facility.
A United Launch Alliance Atlas V rocket, topped by Boeing’s CST-100 Starliner spacecraft, stands on the launch pad at Space Launch Complex 41 at Florida’s Cape Canaveral Air Force Station, Dec. 18, 2019, after rolling from the Vertical Integration Facility. Boeing’s uncrewed Orbital Flight Test will be the Starliner’s first flight to the International Space Station for NASA’s Commercial Crew Program. Photo credit: Frank Michaux

Good morning from the NASA News Center at Kennedy Space Center in Florida. It’s launch day for Boeing’s CST-100 Starliner spacecraft. The United Launch Alliance Atlas V rocket, with Starliner atop, are poised on the launch pad at nearby Space Launch Complex 41 on Cape Canaveral Air Force Station.

Starliner will make its inaugural flight to the International Space Station, called Orbital Flight Test, as part of NASA’s Commercial Crew Program. Liftoff is scheduled for 6:36 a.m. EST during an instantaneous launch window.

Fueling of the Atlas V rocket began at about 12:30 a.m. today. The first stage booster’s RD-180 engine, containing two thrust chambers, was fueled with Rocket Propellant-1 (RP-1), or highly purified kerosene. The Centaur second stage was fueled with liquid hydrogen and liquid oxygen. Fueling of the rocket was completed about two hours later.

Stay tuned for coverage of the countdown events and launch. Watch the coverage live on NASA TV. More details about the mission and NASA’s Commercial Crew Program can be found in the online press kit and by following the @commercial_crew on Twitter and commercial crew on Facebook.

Meteorologists with the U.S. Air Force 45th Weather Squadron continue to predict an 80% chance of favorable weather for launch early this morning. Primary concerns for launch day are the Cumulus Cloud Rule and User Ground Winds violations during the instantaneous launch window.

Tune in for Launch Coverage of Boeing’s Orbital Flight Test

The crew access arm is seen after being moved into position for Boeing's CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket on the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test mission, Wednesday, Dec. 18, 2019 at Cape Canaveral Air Force Station in Florida.
The crew access arm is seen after being moved into position for Boeing’s CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket on the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test mission, Wednesday, Dec. 18, 2019 at Cape Canaveral Air Force Station in Florida. The Orbital Flight Test with be Starliner’s maiden mission to the International Space Station for NASA’s Commercial Crew Program. The mission, currently targeted for a 6:36 a.m. EST launch on Dec. 20, will serve as an end-to-end test of the system’s capabilities. Photo Credit: NASA/Joel Kowsky

Liftoff of Boeing’s CST-100 Starliner spacecraft atop a United Launch Alliance Atlas V rocket, is targeted for 6:36 a.m. EST Friday, Dec. 20 from Space Launch Complex 41 on Cape Canaveral Air Force Station in Florida. This uncrewed mission, known as Boeing’s Orbital Flight Test, is Starliner’s maiden flight to the International Space Station for NASA’s Commercial Crew Program. The main objective of the mission is an end-to-end demonstration of Boeing’s ability to launch astronauts to the orbiting laboratory and return them home. To learn more, read the prelaunch feature.

Meteorologists with the U.S. Air Force 45th Weather Squadron continue to predict an 80% chance of favorable weather for launch on Friday morning. Primary concerns for launch day are the Cumulus Cloud Rule and User Ground Winds violations during the instantaneous launch window.

Join us at 5:30 a.m. Friday, Dec. 20, for countdown coverage on the Commercial Crew blog and NASA TV.

NASA will host an Administrator Post-launch News Conference at 9 a.m. followed by a Launch Team News Conference at 9:30 a.m., both on NASA TV.

Mission Timeline (all times approximate)
Hour/Min/Sec            Events
-06:00:00                   Atlas V fueling commences
-04:05:00                   Atlas V fueling is complete
-04:04:00                   T-4 minute built-in hold begins
-01:25:00                    Hatch closure complete
-01:15:00                     Prelaunch cabin leak checks
-01:05:00                    Cabin pressurization complete
-00:20:00                   Launch Conductor conducts terminal count briefing
-00:18:00                    CST-100 poll for terminal count
-00:15:00                    CST-100 to internal power
-00:10:00                    Crew Access Arm retracted
-00:08:00                   Launch vehicle poll for terminal count
-00:04:45                   Starliner configured for terminal count
-00:04:00                   T-4 minute built-in hold releases
-00:01:00                   CST-100 is configured for launch
-00:00:03                   RD-180 engine ignition

Launch, Landing and CST-100 Deployment (all times approximate)
Hour/Min/Sec          Events
+00:00:01                  Liftoff
+00:00:06                 Begin pitch/yaw maneuver
+00:00:41                  Maximum dynamic pressure
+00:01:05                  Mach 1
+00:02:22                  SRB jettison
+00:04:29                 Atlas booster engine cutoff (BECO)
+00:04:35                 Atlas Centaur separation
+00:04:41                 Ascent cover jettison
+00:04:45                Centaur first main engine start (MES-1)
+00:05:05                Aeroskirt jettison
+00:11:54                 Centaur first main engine cutoff (MECO-1)