On Tuesday, Boeing said the first orbital test flight of its commercial crew capsule, called Starliner, will be delayed until August "to avoid unnecessary time pressures" and prioritize the Atlas 5 rocket manifest to a US Air Force Communications Satellite.
A statement issued by Boeing on Tuesday confirmed previous reports that its CST-100 Starliner spacecraft, designed and built under a $ 4.2 billion contract from NASA, would miss its former target launch date for an unpiloted test flight to the international space station in April. NASA and industrial sources have said for several months that an April start date was not possible, but NASA and Boeing had not officially published a revised schedule since early February.
The first Starliner test flight with astronauts on board was previously scheduled for August. The Boeing schedule update, which was released on Tuesday, said the company only expected Crew Flight Test to appear "later this year," but sources said Starliner could fly astronauts in November at the earliest.
A hotfire test of Starliner interrupting engines delayed from last year after fuel leakage at the test stand at NASA's White Sands Test Facility in New Mexico is scheduled for the coming months. It will be followed by a pad abortion test on White Sands in the summer time frame before Starliner's first space mission, according to Rebecca Regan, a Boeing spokesman.
The Pad Abortion Test will verify Starliner's four liquid fuel engines can ship the canister and astronauts aboard from a failing rocket. The Pad Abortion Test was previously scheduled between Starliner's first orbital mission, designated Orbital Flight Test, and the capsule's first crew mission. Earlier in the spacecraft's development, Boeing originally intended to complete the pad interruption test before both test flights to the space station, but officials blended the sequence after last year's hotfire test anomaly.
With the updated schedule released on Tuesday, Starliner's Orbital Flight Test is blasted into the United Launch Alliance Atlas 5 rocket manifest in Cape Canaveral by Air Force's fifth Advanced Extremely High Frequency Communications Satellite, which has held a target launch date of June 27 for several months. Boeing said Starliner's Orbital Flight Test had a narrow launch opportunity in the first week of May to clear Atlas 5's launch cushion in Cape Canaveral before the AEHF 5 mission.
"In order to avoid unnecessary schedule pressures, do not disturb a critical national security load and allow appropriate time frame to ensure that Boeing, United Launch Alliance and NASA teams are able to successfully complete the launch of Starliner," made the most responsible decision available to us and will be ready for the next launch cache availability in august while still allowing for a crew flight test later this year, "Boeing said in a statement.
Boeing test pilot Chris Ferguson, a former NASA astronaut who ordered the last space mission in 2011, will be joined by NASA crew members Mike Fincke and Nicole Mann on Crew Flight Test mission.
Boeing's CST-100 Starliner is one of two commercially-developed crew caps funded by NASA for fair astronauts to and from the space station. SpaceX's Crew Dragon Spacecraft was launched on March 2 on a six-day test flight to the space station, demonstrating its capabilities before another test, as soon as July with NASA astronauts Bob Behnken and Doug Hurley aboard.
The Crew Dragon capsule returned to the ground under parachutes on March 8 for a splashdown in the Atlantic.
While SpaceX's Crew Dragon launches on top of the company's Falcon 9 rocket and returns to splashdowns at sea, CST-100 Starliner will take onboard Atlas 5 rockets built by the United Launch Alliance, a 50-50 joint venture between Boeing and Lockheed Martin. At the end of each mission, Starliner will fall back to Earth for a landing in the western United States.
Originally, SpaceX intended to reuse Crew Dragon for multiple missions to the space station, but officials have lost this plan at least for now, after reorganizing the capsule into sea landings. Boeing says each CST-100 crew capsule can fly in space up to 10 times.
After completing their test planes, Crew Dragon and CST-100 Starliner spaceships begin regular crew rotation flights to the space station, where they will remain docked as emergency boats for up to 210 days before returning to the Earth astronauts.
Boeing said Tuesday, the Starliner program continues to make progress. The company said it recently cleared the last major test milestones ahead of the unilateral demonstration flight to the space station, and technicians "enter the final stages of production" on the Orbital Flight Test vehicle.
Nevertheless, the Boeing said the delay to August for Starliner's first space mission allows teams to "take the time to ensure that this critical flight is successful and prove that our reusable vehicles will be ready for to fly several long-lasting missions throughout the lifetime of the international space station. "  The Starliner team recently completed two parachute trials, and one of the man-made Starliner spaceships recently completed a series of environmental tests at Boeing's satellite plant in El Segundo, California, officials said.
Boeing builds the CST-100 Starliner capsules in a repurposed space shuttle hangar at NASA's Kennedy Space Center in Florida, where the company also plans to refurbish the spacecraft between missions. Initially, the company plans to build two full-up Starliner capsules for crew rotation flights to the space station, designated Spacecraft 2 and Spacecraft 3.
Spacecraft 1, the first of the line, will be used on the pad abortion test in New Mexico.
The capsule used for environmental testing in El Segundo was Spacecraft 2. The battery of environmental samples exposed the spacecraft to extremely hot and cold temperatures, vacuum conditions, electromagnetic radiation and the vibrations and acoustic environments it will encounter in the flight. With the tested end, the capsule will be returned to Kennedy Space Center for final equipment prior to Crew Flight Test.
Boeing gathers Spacecraft 3 for Orbital Flight Test.
Fuel leakage in Starliner's abortion engines last June led to months of program delays, while engineers studied parallel problems with the Boeing capsule parachutes and pyrotechnic systems. The delays have ultimately caused Boeing to fall months after SpaceX in the launch of their crew capsule's first unilateral space mission.
"Both Boeing and SpaceX work through very different problems with their propulsion systems, and in addition, both providers continue to refine, set, and understand their parachute design," said Sandy Magnus, a former NASA astronaut, during a NASA meeting. Aviation Safety Advisory Panel on March 7. "It is a critical security design element that is an ongoing challenge for both parties."
Boeing said the company is approaching the finish line to overcome the propulsion and parachute challenges.
"With the environmental test, we now only need another parachute qualification test, the service module's hot-fire test and a pad interruption test before we are fully qualified to fly our Crew Flight Test," Boeing said. "None of these tests are required prior to the unclear Orbital Flight Test."
But Boeing said the team wants to fly a crew member spacecraft on the unilateral test.
"It is important for us to fly a complete vehicle and collect as high-physical data as we can from these important flight tests before turning around the vehicles and preparing them for regular long-term missions," the company said in a statement.
SpaceX tested Crew Dragon's abortion system during an on-pad test in 2015, demonstrating the ship's SuperDraco aircraft, has the power to take the spacecraft out of its rocket on the ground in the event of an accident during the countdown. A flight abortion test is scheduled this summer, before Crew Dragon's first mission with astronauts, to evaluate the capsule's ability to escape from a high altitude rocket.
Unlike the flight flight demonstration, a flight test was not on the run as required by NASA from each of the companies, and Boeing opted to leave it.
Crew Dragon, who flew to the space station last month, was launched with much of the space ship's life support system, including air revitalization equipment for the regulation of oxygen and carbon dioxide inside the spaceship. The crew pitches and display screens also flew, but the displays were not activated and functional, according to Hans Koenigsmann, SpaceX's vice president of building and flight reliability.
The screen crew operations, push buttons and toilet will be added to the next Crew Dragon vehicle for astronauts.
SpaceX also plans to add heaters to the Crew Dragon's propulsion system to keep the propellants too cold, which can cause shocks or vibrations that can damage the capsule's Draco steering funnels.  Speaking on the security panel last month, says Magnus SpaceX and Boeing various plans for their test flights.
"It is not possible to make a direct comparison of the two effortless flights and the milestones they perform," said Magnus. "They are different for different reasons for each provider. Each provider has targeted different goals and it is based on their business concept and design philosophy."
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