As Boeing’s CST-100 Starliner crew transportation vehicle for NASA continues to meet its processing milestones at the Kennedy Space Center and various test sites around the country, United Launch Alliance, the company tasked with launching Starliner on its journey toward the International Space Station, has made the decision to swap the Atlas booster that will power Starliner’s first flight next year. Meanwhile, the first crewed Starliner mission appears to be slipping to “late 2018”.

Starliner processing:

Overall, things are going exceptionally well for Boeing in their construction efforts for the CST-100 Starliner crew transportation vehicle.

With primary build operations taking place inside the Commercial Crew and Cargo Processing Facility (C3PF) (formerly known as Orbiter Processing Facility bay 3), the latest information points toward Boeing being on track to meet the uncrewed and crewed demo launch timelines in 2018.

The latest confirmed schedules from NASA show the uncrewed mission, dubbed the Orbital Flight Test (OFT), slated for No Earlier Than June 2018, followed quickly in August 2018 by the crewed flight test.

However, comments made by Chris Ferguson last month at the Paris Air Show seem to indicate that the crewed flight test is moving from its August timeframe.

According to Mr. Ferguson, Director of Crew and Mission Operations for Boeing’s Commercial Crew Program, the first Starliner crewed test flight is aiming for “last quarter of 2018” – which would be a shift of two to five months into the October to December 2018 timeframe.

Based on Mr. Ferguson’s statements, this move appears to be based on “expressed timelines” from NASA.

Regardless, a firm date for Starliner’s crewed test flight won’t be known until the completion of the OFT mission – which, at the Paris Air Show, Mr. Ferguson confirmed is on track for “June 18.”

To that end, Boeing engineers are hard at work to meet the various milestones needed ahead of the OFT mission.

Currently, the company’s technicians and engineers are running leak checks on the propulsion system for the Service Module Hot Fire Test article (SMHFT) inside the C3PF at the multi-user Kennedy Space Center.

The SMHFT is integral to Boeing’s milestones toward the first uncrewed flight, with the SMHFT scheduled to ship to NASA’s White Sands test facility in New Mexico later this year for hot fire testing.

During flight operations, Starliner’s Service Module propulsion system provides launch abort capability on the pad and during ascent along with propulsion needs during orbital operations, including launch vehicle separation, docking to and undocking from the ISS, and separation of the crew and service modules after deorbit but before reentry.

As such, full up testing of the Service Module – accomplished through the SMHFT – is critical before flight operations begin.

Also occurring in the C3PF is the construction of the first Starliner capsule that will fly the OFT mission in June of next year.

Engineers and technicians have already completed construction of the Structural Test Article (STA) for Starliner – which is currently in California undergoing testing.

Construction of the STA provided valuable insights to the team ahead of build operations for the three operational Starliners.

While the first complete Starliner will not carry crew – as the OFT mission is an uncrewed test flight – the capsule will be retrofitted after the OFT to carry crew on subsequent missions.

With the first Starliner flight now less than a year away, engineers have completed all pre-mate electrical checks between the Upper and Lower Domes of the first Starliner.

Mating of the Upper and Lower Domes is currently scheduled for 14 August 2017 and will mark the completion of a major milestone in the first Starliner’s construction.

Meanwhile, as construction efforts for Starliner continue on pace for a June launch of the OFT, United Launch Alliance (ULA) has made the decision to swap the Atlas V first stage booster that will power the first Starliner to orbit.

Originally, the OFT mission had been slated to launch on AV-082, Atlas Vehicle 82.

According to the latest information, that has now changed on ULA’s end, with the company opting to swap AV-082 for AV-080.

While the reason for the first stage Atlas V swap is unknown, the change to the first stage is expected to have little effect on flight operations or NASA’s clearance to launch the OFT mission to the ISS next year.

NASA Docking System requirement updates:

Physical construction milestones and launch vehicle selection aren’t the only milestones being worked by Boeing in regard to Starliner.

This month, NASA met with Boeing and their software development team regarding the NASA Docking System (NDS) on the ISS and potential requirement changes in software design.

The NDS is the new generation docking structures, systems, and software that replaces those used by the Space Shuttles during construction and outfitting missions for the International Space Station between 1998 and 2011.

With the retirement of the Shuttles and NASA’s desire to extend the Station’s structural lifetime through low energy impact dockings, the agency has undertaken the task of changing the capture mechanisms at the end of the Pressurized Mating Adapters on the US segment of the Station.

The first major hardware steps toward this change occurred last year when SpaceX resupply mission CRS-9 delivered the first new International Docking Adapter (IDA) to the station.

The IDA delivered by CRS-9 was actually IDA-2 as IDA-1 was lost on the CRS-7 launch mishap in June 2015.

As the first use of the new IDA capture mechanisms approaches, NASA has been refining the software requirements they wish Boeing – and the other commercial crew launch provider, SpaceX – to use when their vehicles dock to the ISS next year.

The recent meeting with Boeing was largely to discuss potential changes NASA wishes Boeing to employ in its docking software and any potential impacts these software changes might hold to the OFT or crewed demonstration missions next year.

Moreover, the meeting discussed the potential of accelerating the planned NDS software changes so that any potential impacts on Boeing side could be mitigated.

According to the latest information obtained by NASASpaceflight.com, this meeting went well, with an understanding that the current requirement changes will not impact Boeing’s software development schedule for OFT or the crewed demonstration missions.

While not directly related to the NDS, a better understanding of Boeing’s docking hopes for Starliner became clearer last month during Mr. Ferguson’s question and answer session at the Paris Air Show.

Here, Mr. Ferguson noted his desire for Starliner to perform the rapid sequence 6 hour launch to docking profile currently employed by Soyuz crew vehicles and Progress uncrewed resupply vehicles from Russia.

At most, Mr. Ferguson stated his desire for Starliner to employ 24-hour launch to docking profiles – due in part to the vehicle’s design, which limits its free flight capability (from launch to docking and then undocking to landing) for an entire mission to just 60 hours.

(Images: Boeing, SpaceX, NASA, and L2 artist Nathan Koga – The full gallery of Nathan’s (Starliner to SpaceX Dragon to MCT, SLS, Commercial Crew and more) L2 images can be *found here*)