Star Mega DO III has officially launched, with the opportunity to join in for a once-in-a-lifetime experience.

Events kick off September 5 with an optional European program (and deeply discounted business and economy tickets between New York and Munich). Last year’s event featured an after-hours party in Lufthansa’s First Class Terminal in Frankfurt. The year before there was even an emergency slide popped for members of the trip.

The full event begins at the Park Hyatt Chicago on Wednesday, September 7 with management of United and Hyatt. The next morning there’s a behind-the-scenes tour at O’Hare, followed by a champagne magic show in the Red Carpet Club, charter flight to Montreal for an Air Canada and Aeroplan program and a Bombardier factory tour. It’s on to Denver for a United training center tour and a charity auction for flight simulator time and tentatively an Air National Guard tour with potential for F16 rides and a Lockheed Martin tour.

United is offering double, triple, and even quadruple qualifying miles for the charter flights (depending on class of service). Hyatt is giving all participants Diamond elite status through February 2013.

Pricing and more details are posted over at Milepoint, but since this is just put together by frequent flyers for frequent flyers it’s surprisingly affordable — coach seats on the charter run $750 all-in, and there are good group discounts on the hotels.

Sponsors and partners are United Airlines, Lufthansa, Air Canada/ Aeroplan, Hyatt, Bombardier, milepoint.com, usingmiles.com, and awardwallet.com.

A good snapshot of what a Star Mega DO is all about was captured in a Wall Street Journal piece on the 2009 event

The Mega DO—which started in Chicago—gave the road warriors an education in how airlines work. At each stop, airline executives greeted them with singers and dancers, mechanics and pilots, ample food and drink and tours of engine shops, training facilities, airplanes and hangars.

Like kids on a school field trip, they filed through crew briefing rooms at UAL Corp.’s United Airlines in Chicago, quizzed maintenance experts at Continental’s engine shop in Newark, practiced flight-attendant skills at Lufthansa’s training center in Frankfurt and were photographed sitting in various aircraft cockpits opened for them at hangars.

They asked airline workers about snow plows at O’Hare, bird-strikes in engines, access to airport clubs and the environmental impact of deicing fluid. They learned how airlines cycle engines and airplanes through scheduled maintenance, how company workers assign gates and direct aircraft movement around terminals, how pilots prepare for long journeys and how Airbus puts together its giant double-deck plane.

.. and also in a big spread in Conde Nast Traveler. Photos from past Star MegaDOs can be found on the Facebook page.

Contracts are signed and DOT approval has been received for the charter, so the website for signing up will launch this weekend. There’s only 135 spots available (fewer than last year due to smaller aircraft), so it’ll be necessary to jump on the opportunity.