SpaceX-tra! Read all About It…

posted May 23, 2012 by Miles O'Brien

The Dragon capsule is homing in on the ISS and so far the systems shakedown has not created any show-stoppers: the solar arrays have deployed, the navigation pod bay doors have opened (as Elon tweeted: “So much nicer than HAL9000 ”), the abort system has been tested and the craft has successfully gone into “free drift” mode.

All of these steps are essential before NASA will give a “go” for rendezvous and grapple by the ISS robot arm on Friday morning EDT. By the way, Dragon is not “docking” at the station despite a lot of inaccurate reporting to the contrary. The capsule will get close enough to be captured by the arm and then attached to the station.

 

Dragon is not equipped with the so-called “Androgynous Peripheral Attach System” – required for an ISS docking.

The short video above is my conversation with Jeffrey Brown on the PBS NewsHour set Tuesday evening.

Bill Harwood has posted a full timeline for Dragon’s encounter with the station here. But here are the key events to follow on berthing morning (all times EDT).

04:18:58 AM…03…00…34…20…Approach initiation (HA4) burn
04:35:38 AM…03…00…51…00…HA4-MC1 burn
04:52:18 AM…03…01…07…40…HA4-MC2 burn
05:13:58 AM…03…01…29…20…Range: 350 meters; yaw 180 degrees
05:18:58 AM…03…01…34…20…Resume approach
05:28:58 AM…03…01…44…20…Range: 250 meters
05:43:58 AM…03…01…59…20…Resume approach; begin retreat/hold demos
06:08:58 AM…03…02…24…20…Hold at 220m (evaluate retreat/hold demoss)
06:23:58 AM…03…02…39…20…Resume approach inside keep-out sphere (KOS)
07:13:06 AM…03…03…28…28…Sunrise
07:13:58 AM…03…03…29…20…Range: 30 meters
07:28:43 AM…03…03…44…05…Resume approach
07:48:43 AM…03…04…04…05…Capture point arrival
07:58:43 AM…03…04…14…05…Go’ for capture
08:06:43 AM…03…04…22…05…Capture
08:10:24 AM…03…04…25…46…Sunset
08:45:38 AM…03…05…01…00…Sunrise
09:00:38 AM…03…05…16…00…Latest go for capture
09:10:38 AM…03…05…26…00…Latest CP arrival
09:25:38 AM…03…05…41…00…Earliest go For capture
09:30:38 AM…03…05…46…00…Earliest CP arrival
09:42:58 AM…03…05…58…20…Sunset
10:18:10 AM…03…06…33…32…Sunrise