Washington – A mock Soyuz countdown is underway at the European spaceport near Kourou, French Guiana, validating ground operations up to but not including fueling of one of the first two Russian launch vehicles to reach the equatorial launch site on the north coast of South America.
The dry-run checkout started April 29 with transport of the flightworthy launch vehicle 600 meters from its “MIK” horizontal assembly building to the new pad on its transporter/erector rail car. At the pad, a strongback crane erected the vehicle to the vertical position, where it was suspended on four primary support arms over the concrete pad and flame pit
Up until that point the procedure closely tracked the one followed at the two Soyuz pads at the Baikonur Cosmodrome in Kazakhstan, where Soyuz rockets routinely launch piloted Soyuz capsules and unpiloted Progress resupply vehicles to the International Space Station, as well as Russian unmanned payloads and commercial unmanned payloads managed by the European-Russian Starsem joint venture.
However, at Kourou the vehicle is enveloped by a 52-meter-tall mobile gantry that is rolled into place around it for installation of the payload, which is integrated horizontally at Baikonur and erected with the rest of the rocket.
At Kourou the ground-validation pathfinder vehicle includes a Fregat upper stage and payload fairing, but no payload. Those were stacked atop the vehicle – four strap-on boosters, the Block A second stage, and the Block I third stage – inside the moving gantry.
Testing of the medium-lift vehicle will continue at the pad until May 5, and will include all of the events leading up to a simulated countdown interruption on launch day. The vehicle will not be fueled with kerosene and liquid oxygen.
The countdown will be restarted on May 6, leading up to a simulated launch and downrange operations, according to Arianespace, which oversees Soyuz operations at Kourou and will market Soyuz launches from there.
[Editor's note: the launch vehicle was erected to its horizontal position April 29. An earlier version of this article misstated the position.