SpaceX Falcon 9 rockets in production.

NATIONAL HARBOR: When will the Air Force certify SpaceX as ready to launch military satellites — if they certify the upstart startup at all? The new chief of Air Force Space Command said this morning that “hopefully” he could certify SpaceX by December 1st. Just hours later, though, the Secretary of the Air Force, Deborah Lee James, cautioned that schedule was “aggressive” and said early 2015 is probably more realistic.

SpaceX’s sharp-elbowed CEO, billionaire Paypal co-founder Elon Musk, is plenty aggressive himself: He’s won considerable support in Congress and went so far as to file two lawsuits and a formal protest against Air Force awards to the current nigh-monopoly, the Boeing-Lockheed Martin United Launch Alliance. But both Sec. James and Gen. John Hyten made clear that certification is far from certain.

Whatever the details on timelines, “the greater point is that certification is not a done deal,” Sec. James told reporters this afternoon at the annual Air Force Association conference here. “We must assure ourselves that a new entrant like SpaceX could do the mission.”

“Goodness knows, I want competition in this area,” Gen. Hyten said this morning at AFA, “but the most important thing for this nation is assured access to space that works all the time…. That’s why the certification of SpaceX, hopefully by December the 1st, is a big event — but if they’re not ready on December the 1st, we have to stand up and say that.”

Hyten’s predecessor at Air Force Space Command, Gen. William Shelton, told reporters at the Pentagon on July 22nd — his last before retiring in August — that he was working for a December certification but he thought it was “a very optimistic schedule.”

Sec. James didn’t sound that optimistic when a reporter asked her about the Dec. 1 date this afternoon. “The target times that I have heard when SpaceX will be hopefully ready is anywhere from the end of the year into the first part, call it the the first quarter, of next year,” she said. “I didn’t hear what Gen. Hyten said today, but that sounds a little bit aggressive vis-a-vis what I have heard.”

So while there’ll probably be some kind of announcement circa Dec. 1st, it may say that SpaceX needs to go back to the drawing board. Or it could be an anti-climactic “we’re still working on it” — the bureaucratic equivalent of that spinning beachball Apple devices display when something’s taking too long to load.

SpaceX’s reported win of a NASA “space taxi” contract  doesn’t change that equation, James said: SpaceX must go through the Air Force process for what’s called the Evolved Expendable Launch Vehicle (EELV) program. She added, though, that NASA’s certification standards for manned spaceflight programs, like the space taxi, are generally even higher than EELV’s.

All in all, Gen. Hyten seemed more pro-SpaceX than his predecessor Shelton, who sometimes sounded frustrated with the company. (“Generally, the person you are doing business with, you don’t sue,” he groused to my colleague Colin Clark in May). Hyten, by contrast, said that he’s rooting for them:

“Like every American, I love competition, I love entrepreneurs,” Hyten said this morning, “I want you to know that I root for SpaceX to come into the competition… but my fundamental requirement as the commander of Air Force Space Command, as an officer in the United States Air Force, is to make sure the United States has access to space, assured, all the time, and that means it has to work every time.”

Years of cuts and delays to a relatively small number of high-priced satellites means the various communications and surveillance systems now in orbit have very little margin for error. “We have put ourselves in the position [that] every constellation except GPS is a little bit fragile,” Hyten said.

Twice in the past, the Defense Department lost assured access: First after the Challenge disaster in 1986, which forced the military to scramble for an alternative to the Space Shuttle, and again in the late 1990s, when a series of accidents grounded the Titan IV and Delta rocket fleets. Both times, “we ended up with huge voids in our warfighting capability,” he said. “So the fundamental prime directive has to be assured access to space.”