Forget about that train wreck—a top Obamacare official feared during the summer that HealthCare.gov would be a plane "crash."
Obamacare's top IT manager, Henry Chao, was deeply concerned in July that the federal insurance marketplace website would bomb when it launched because of ongoing problems with contractors, eye-opening documents released Friday showed.
"I just need to feel more confident they are not going to crash the plane at takeoff, regardless of the price," Chao wrote another Centers for Medicare and Medicaid Services official, Monique Outerbridge, on July 16, less than three months before the badly botched launch of HealthCare.gov. "Figure out how to get that conversation conducted and message conveyed."
And four days later, Chao pointedly noted to Outerbridge and a slew of other CMS officials that he and their boss Marilyn Tavenner were sticking their necks out with public "under oath" promises to Congress that HealthCare.gov would work when launched.
"Below are information and links to the Congressional hearing Marilyn Tavenner and I attended this past Wednesday," Chao wrote, pointedly. "I am not sharing this with you because I think it's entertaining and informative. I wanted to share this with you so you can see and hear that both Marilyn and I under oath stated we are going to make October 1st."
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"I would like you [to] put yourself in my shoes standing before Congress, which in essence is standing before the American public, and know that you speak the tongue of not necessarily just past truths but the truth that you will make happen, the truth that is a promise to the public that millions of people depend on for us to make happen."
Chao's email, and others related to deadline concerns about HealthCare.gov, were released by the House Energy and Commerce Committee, which has been conducting oversight hearings into the tech-troubled website.
HealthCare.gov's many software issues have seriously affected enrollment in Obamacare insurance, with just 27,000 or so people signing up from 36 states in the first month of operation. The Obama administration is engaged in a round-the-clock effort to fix the site.
But its dismal performance to date spurred President Barack Obama on Thursday to allow insurers who had been canceling people's policies because they did not comply with the Affordable Care Act to continue with those policies for the next year.
Committee Chairman Fred Upton, R-Mich., said of the memos, "Administration officials looked us in the eye and told us everything was 'on track' but when we pull back the curtain now, the mess is disturbing."
"What reason do the American people have to believe that the administration is capable of meeting its Nov. 30 goal for fixing HealthCare.gov or its Jan. 1 promise to deliver health care to Americans across the country," Upton said. "The botched rollout has created a serious question of competence and trust in the administration that we will continue asking at our hearing next week."
A CMS spokeswoman, in a statement Friday, said: "This email discusses one small piece of ongoing discussions about managing deliverables and communicating expectations that were on a short timeline to meet Oct.1. Management concerns about meeting timelines are expected for any project of this size and scope."
"The federal marketplace is comprised of distinct pieces of functionality that, together, make up the full integrated system—plan management, eligibility and enrollment and financial management. CMS prioritized essential functionality to be live on Oct. 1 to ensure that consumers would be able to apply for eligibility and select a plan. Other functionality will come online over time. This is a complex project with a short timeline—and as such issues were prioritized to meet the Oct. 1 launch date."
CMS and Health and Human Services Secretary Kathleen Sebelius previously have told Congress that none of the contractors working on HealthCare.gov warned officials that the site would not be ready by Oct. 1.
And an executive from CGI Federal, the lead contractor for the project, has testified the company believed the system was ready to go that day.
In another email released by Upton's committee, CMS official Jeffrey Grant wrote a memo on July 8 to two other CMS officials about serious issues involving the contractors and their looming deadline.
Grant's email refers to a section of HealthCare.gov known as "FM," which according to administration officials stands for "financial management tool." Officials ended up not activating that function on the site in the rush to get HealthCare.gov live by the Oct. 1 launch.
"We just got off an extended set of development planning meetings with OIS [Office of Information Services]," Grant wrote.
"Suffice to say, the upshot is that the FM build appears to be way off track and getting worse," Grant wrote. "We also finally were told that there are only 10 developers total working on the FM build for all functionality."
"Only one of these developers is at a high enough skill level to handle complex issue resolution, which now appears to be required for all aspects of our build," Grant wrote.
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Grant concluded his email by saying, "While OIS has always said we had an independent team for FM development, they have never revealed the seriously substandard level of staffing that this team has."
"We believe that our entire build is in jeopardy," Grant wrote. "I think we need to consider which items in our build will not be done if we don't get substantially greater staffing levels."
—By CNBC's Dan Mangan. Follow him on Twitter