Just as every race car driver has a pit crew to keep them on track on the way to a victory quickly and safely, the seven aerospace companies that have teamed up with NASA's Commercial Crew Program have their own PIT Crews, called Partner Integration Teams, to help guide them in their race to space.

They're not packing an arsenal of air compressors, fuel, or even spare tires, though. Instead, NASA PIT Crews are equipped with the intimate knowledge of what is takes to design, develop, manufacture, process and launch space transportation systems. Lately, those teams have been making significant progress under Commercial Crew Development Round 2 (CCDev2).

"We call this insight," said Scott Thurston, who is leading the PIT Crews as chief of the Commercial Crew Program (CCP) Partner Integration Office. "We're there to glean the information and then watch, and help, if needed. Be a part of their program, but not get in the way."

Each PIT Crew is made up of about 10 to 15 dedicated spaceflight experts, supported by 10s if not 100s of system expert engineers, who are available to help industry partners meet their established milestones in developing commercial crew transportation capabilities.

Their expertise ranges from engineering and safety to health and medical and mission operations. Representatives from the Federal Aviation Administration and NASA's Astronaut Office also are members of the seven PIT Crews, one for each of the seven funded and unfunded CCDev2 partner companies.

Thurston said CCP is very much like a venture capitalist endeavor because NASA is investing in systems and laying out expectations, but not dictating how companies make their systems work.

"You know, it's funny, it's the companies telling us why they feel comfortable about their systems," Thurston said. "It's not them telling us why it's OK to buy their spacecraft or launch vehicle, but why it's OK to invest money in them."

"The milestones are really the mile markers of each one of these companies," Thurston said. "It's based on each company's development plan, not what the government wants, so each company is a little bit different."

Some of the spacecraft and launch vehicle designs are infant in nature while others have been proving their experience and reliability for many years.

United Launch Alliance (ULA), for example, has 28 successful launches under its belt with the Atlas V rocket. For CCDev 2, ULA and NASA are working under an unfunded Space Act Agreement to assess human rating that system.

"Many want to know why the Atlas V needs to be assessed to fly humans, after all, they've been flying high-value robotic, science and defense missions for years," said Cheryl Malloy, the NASA partner manger for ULA.

Malloy's answer is simple: "If there's a problem with the spacecraft or rocket during ascent, options must be available to abort the mission and bring the crew back to Earth safely."

To develop that abort capability and keep the cost of human spaceflight affordable, NASA and ULA are exploring "kitable" solutions that would only be added to a rocket when launching humans.

During ULA's recent Tailored System Requirements Review, NASA received an in-depth look at what it would take to get a crew in and out of a spacecraft on the launch pad, a dual engine configuration on the upper stage that would improve performance, an emergency detection system, and vehicle structural modifications that would accommodate unique spacecraft designs.

Blue Origin also completed two milestones for the development of its Space Vehicle. First, the company completed a Mission Concept Review in which NASA was able to look at the goals and objectives, high-level requirements, mission feasibility, concept evaluation criteria and risks associated with the spacecraft. The second was a review of the company's plan to hot-fire its Reusable Booster Stage Engine Thrust Chamber Assembly (TCA).

"The teams reviewed the TCA interface control diagram requirements, test plan and systems requirements document for testing at NASA's Stennis Space Center in Mississippi," said Bill Lane, the NASA partner manager for Blue Origin. "After that hot-fire, Blue Origin will deliver a test report to NASA."

Lane said the company's pusher escape team continues to make progress toward the upcoming motor ground firing and pad escape testing milestones. Blue Origin's space vehicle team also is continuing with spacecraft system designs that will lead to the System Requirements Review milestone scheduled for May.

Boeing recently completed a simulation between the launch vehicle emergency detection system and avionics system integration facility for its CST-100 spacecraft. The spacecraft also underwent wind tunnel testing.

"We are looking forward to several other significant milestones," said Gennaro Caliendo, the NASA partner manager for Boeing. "Next will be the launch abort engine fabrication and hot-fire demonstration, and then a full-up landing system air drop demonstration test where the capabilities of the parachutes and air bags are tested."

Excalibur Almaz Inc. (EAI) is considered the newcomer to CCDev2, but has jumped into the space race full throttle with plans to upgrade its heritage hardware with American-made life support systems.

"This whole program is really like a portfolio," Thurston said. "We're not just going with people we know, we're also enticed to work with people who might do things considerably different."

"Both EAI and the PIT Crew currently are preparing for the upcoming System Requirements Status Review," said Sarah Waechter, EAI's partner manager for NASA. "We also are looking forward to the Launch Vehicle Compatibility Review where we will discuss the initial spacecraft to launch vehicle integration."

Sierra Nevada Corp. (SNC), which is the only CCDev2 company building a winged spacecraft, just delivered the structural pieces for its Dream Chaser Engineering Test Article (ETA) to its plant in Louisville, Colo.

"The company can now begin assembly and integration of their secondary structures and subsystems," said Valin Thorn, SNC partner manager for NASA. "This will lead to the ETA captive carry flight test scheduled for this spring."

During that test, a Virgin Galactic White Knight 2 carrier aircraft will drop the Dream Chaser test article over NASA's Dryden Flight Research Center in Edwards, Calif., to measure its performance.

Alliant Techsystems Inc. (ATK) has been focusing its attention on TIMs, which are Technical Interchange Meetings. The first focused on preliminary models and design analysis planning of the Liberty launch vehicle, including certification, requirements allocation, safety and mission assurance, as well as failure and hazard analysis data. Ken Tenbusch, NASA partner manager for ATK, said his team is looking forward to the second TIM, which likely will include more details of ATK's upper stage design.

"Our NASA team is excited about working with ATK's French partner, Astrium, and supporting their efforts in converting the core stage of the Ariane V rocket that will become Liberty's upper stage," Tenbusch said.

Jon Cowart, NASA partner manager for SpaceX, said he and his PIT Crew are working with the company while it develops a launch abort system and outfits the Dragon capsule with interior systems, such as seats, displays, air circulation, and air conditioning and heating.

"When you add humans into the mix it really complicates things," said Cowart. "We need to keep the crew alive and informed about what's going on around them."

The most recent milestone SpaceX completed was the second Design Status Review, which gave CCP an overview of the entire system, from the Falcon 9 rocket and capsule to the Merlin engines that help loft the system into space. The company also completed a full-duration, full-thrust firing of its new SuperDraco development engine in preparation for the ninth milestone to be completed under its funded Space Act Agreement with NASA.

"We're actually seeing smoke and fire, which is pretty exciting," Thurston said.

Much like the person in a pit crew who washes the windshield during a race, the CCDev 2 partner managers are keeping their industry partners on a clear path toward ferrying U.S. astronauts to and from the International Space Station in just a few years.

"We make sure that they're channeled and focusing in on the things that we're most concerned about," Cowart said.