That's the date that Burt Rutan as set for his first X-Prize attempt. And just to keep things interesting, he's not alone:

Hot on Rutan’s heels is Brian Feeney, leader of the Canadian da Vinci Project. Feeney also reported today that his team is rolling out on August 5 their completed X Prize vehicle -- the balloon-lofted Wild Fire rocket. The public unveiling will take place at the team’s Downsview Airport hanger in Toronto.

The da Vinci Project Team, widely heralded as a contender for the $10 million purse, will pursue its own Ansari X Prize space flight attempts this Fall.

And Paul Allen remains coy about future plans:

"This competition has proven that there are many different ways to attack the challenges set out by the Ansari X Prize. From the start we have approached SpaceShipOne with a 'can-do, home-brew' attitude," Allen said. "We are grateful that our previous flights have brought even more attention to the Ansari X Prize and given more momentum to the groundswell of excitement that is continuing to build for the long-term potential of affordable space exploration."

Dosn't sound like he thinks it's a stunt.

First off, kudos to Scaled and to the da Vinci Project for their success to date.

However...Scaled has given its 60 days' notice, and the da Vinci Project has only announced the "unveiling" of their vehicle (and therefore likely won't give 60 days' notice before then). Barring major accident, doesn't it seem like Scaled still has the X-Prize in the bag? Even if Scaled does mess up and set themselves back by, say, a month, the da Vinci Project team would still have trouble catching up.

It's certainly Burt's race to lose, but things can go wrong. But while it would be nice to see a dark horse win the prize, the fact that a Canadian team could come in second on a shoestring is still great.

As a Canadian, I agree.

Wasn't it 30 days notice? Regardless, it's certainly good news...

I wonder how many other groups will end up bringing their vehicles to the public, if not actively trying for the full flight, before it's won.

And since I did a little bit of Kremlinology last time:

Two weeks after Sept.29 is Oct.13. The flight of Voshkod 1, first multi-man spacecraft, was Oct.12/13 1964...

As before, I don't think this is worth reading much into; I do think it's an interesting way to play with the history, if you see what I mean -take an arbitrary date, and find something for it to mark. (Especially considering that logic would dictate making the second attempt with several days to spare, in case of solvable glitches)

While we're speculating- is it possible that there could be another flight between now and September 29th? From what's been coming out of Scaled, it sounds like they think they have a pretty good handle on the problems they experienced on the first flight, but would they want to try for a test flight of those modifications before going for the X-prize?

Or would they already have had to give public notice of any flight between now and the 29th?

He can fly as much as he wants between now and then, but I'm interpreting his decision as a statement that it's not necessary. If there were any doubt about their ability to make the flights without a test flight, they would have had a test flight before they made the announcement. It's not a cheap vehicle to fly, so I'd be surprised if there are any flights before the attempt, since there'd be no point.

Wasn't it 30 days notice? Regardless, it's certainly good news...

Yes that's the rules. However, the X-Prize Foundation has asked that contestants give 60 days notice which Scaled Composites did. Isn't it kind of scary that we recall the rules that well?

Makes sense. Out of curiosity- do I remember something about the spaceport Rutan's using having a public notification requirement for launches, or is that not correct?