Launch News SpaceX Falcon 9 F3 COTS2+ Updates

[Codz]

The Dragon/ISS pass is going to occur right over me!

 

[Urwumpe]

Urwumpe, if I understand you correctly, are you saying the main engine and gas-generator exhaust(roll-control) are set apart such that their thrusts (and torques)nominally balance?

Not sure I've phrased that well

N.

Yes, exactly that. Instead of changing the direction of the thrust vector to compensate for the gas generator exhaust, and loosing a few m/s to control losses, you place the engine and the gas generator exhaust in such a way that the torques are nominally neutralized, but both thrust vectors contribute completely to forward acceleration.

It isn't that much that is needed, rather a matter of millimeters - but what isn't in spaceflight?

 

[IronRain]

Spaceflight Now:

Dragon is now about 100 kilometers (62 miles) behind the space station and 9.5 kilometers (5.9 miles) below the space station, mission control in Houston just radioed the crew.

Rendezvous procedures now are running about an hour late.

SpaceX and NASA are go for a height-adjustment burn at 3:58 a.m. EDT (0758 GMT). A so-called coelliptic burn will follow on the other side of the world 45 minutes later to place Dragon on course for its 1.6-mile fly-under of the space station.

The timeline calls for the communications test between the space station and Dragon to occur at 6:28 a.m. EDT (1028 GMT). The vehicles are linked via a system called the COTS UHF Communications Unit, or CUCU.

A command panel inside the space station is available for the crew to issue instructions to Dragon. Today's demo will be for the crew to command an external light on Dragon to turn on, verifying the link works. The system is required for the crew to order Dragon to hold, abort, and prepare for capture with the robotic arm.

 

[IronRain]

Spaceflight Now:

The burn is complete, and the next maneuver is set for 4:43 a.m. EDT (0843 GMT).

 

[IronRain]

A thruster firing has begun to level off Dragon's climb to a point 1.6 miles under the space station's orbit. Dragon is now about 40 kilometers, or about 25 miles, behind the space station now.

Added later:

The co-elliptic burn is complete and Dragon is now at an altitude 1.6 miles below that of the International Space Station, beginning today's fly-under activities. Dragon's relative GPS navigation and the space station crew's command to turn on Dragon's strobe light are coming up.

Added later:

SpaceX reports Dragon's fly-under will occur at a distance of 2.4 kilometers, or 1.5 miles, under the space station.

Space station flight engineer Andre Kuipers is powering up the UHF communications unit linking the complex with Dragon. The crew will issue a command to turn on Dragon's strobe light via the UHF system at about 6:28 a.m. EDT (1028 GMT). That is a key test of the crew's ability to tell Dragon to abort or hold its approach when it moves closer to the station tomorrow.

 

[IronRain]

Spaceflight Now:

Astronaut Don Pettit aboard the space station is troubleshooting a problem with a robotics work station in the lab's cupola due to be used to grapple Dragon tomorrow as it hovers about 30 feet below the outpost. NASA says it's no issue if the work station is not recovered in time. There is a backup robotic arm control station in the Destiny laboratory module.

Added later:

Dragon is expected to cross directly underneath the space station at about 7:26 a.m. EDT (1126 GMT). The crossing of the R-bar - an imaginary line between the station and Earth - will mark Dragon's closest approach to the complex today.

Added later:

Dragon's relative GPS navigation test is mostly complete, but SpaceX and NASA engineers will spend a few minutes analyzing data to check if the system worked as expected.

Added later:

Dragon is now 23 kilometers, or 14 miles, behind the space station and 2.5 kilometers, or 1.6 miles, below it.

 

[N_Molson]

THURSDAY, MAY 24, 2012
0958 GMT (5:58 a.m. EDT)

Astronaut Don Pettit in the space station's cupola reports he sees the Dragon spacecraft out the window.

---------- Post added at 10:28 AM ---------- Previous post was at 10:04 AM ----------

THURSDAY, MAY 24, 2012
1026 GMT (6:26 a.m. EDT)

SpaceX is configuring for two-way communications with the space station, and the test to issue a command to turn on Dragon's strobe light is expected to be about 10 minutes away. And the station reports their monitors now show data from Dragon.

 

[IronRain]

THURSDAY, MAY 24, 2012
1041 GMT (6:41 a.m. EDT)

Dragon's thermal camera has spotted the International Space Station, according to SpaceX.

 

[N_Molson]

THURSDAY, MAY 24, 2012
1046 GMT (6:46 a.m. EDT)

Space station flight engineer Andre Kuipers is now checking out the UHF communications link between the complex and Dragon. This will involve telling Dragon's strobe light to turn on as a check of the station's ability to command Dragon.

Note : the capsule is too far (and white) and the Sun to bright for the astronauts to see the strobe light. However, systems report it is working.

---------- Post added at 10:50 AM ---------- Previous post was at 10:48 AM ----------

THURSDAY, MAY 24, 2012
1047 GMT (6:47 a.m. EDT)

Telemetry is showing the command was successfully issued by Kuipers. Awaiting word on whether the strobe light illuminated.

---------- Post added at 10:54 AM ---------- Previous post was at 10:50 AM ----------

THURSDAY, MAY 24, 2012
1050 GMT (6:50 a.m. EDT)

Dragon will fly directly under the space station in about 30 minutes.

THURSDAY, MAY 24, 2012
1048 GMT (6:48 a.m. EDT)

Kuipers reports Dragon is too brightly illuminated by the sun to visually confirm whether the strobe light turned on, but telemetry indicates the test was a success. This is a crucial point in today's fly-under because it tests the station's ability to issue abort and hold commands to Dragon in the event of a problem during final rendezvous and berthing tomorrow.

---------- Post added at 10:56 AM ---------- Previous post was at 10:54 AM ----------

BTW, very nice views from the ISS cams on the live channel :thumbup:

---------- Post added at 10:57 AM ---------- Previous post was at 10:56 AM ----------

A camera locked up on the Dragon ! A blurry white spot, as the spacecraft is quite small relatively to the distance.

 

[IronRain]

Dragon:

 

[N_Molson]

THURSDAY, MAY 24, 2012
1057 GMT (6:57 a.m. EDT)

After astronauts sent a successful command to turn on Dragon's strobe light, the space station's cameras have spotted the spacecraft as it approaches from below and behind the complex. It appears as a bright dot above Earth's limb.

---------- Post added at 11:09 AM ---------- Previous post was at 11:03 AM ----------

Now the Dragon is over a background of clouds and appears as a dark spot.

 

[Marvin42]

Dragon with

Another picture with Dragon in lower left and solar pannels extended

 

[C3PO]

Implying the roll control wasn't?

Edit: that was from the Inaugural Launch(updated June9,2010)

The gas-generator nozzle got stuck on that flight.

 

[N_Molson]

THURSDAY, MAY 24, 2012
1125 GMT (7:25 a.m. EDT)

The space station is flying out of communications range with the ground, but Dragon should now be coasting 1.6 miles directly underneath the complex.

The next engine burn is set for 7:57 a.m. EDT (1157 GMT) to lower Dragon's orbit as it begins a flyaround ahead, above, then behind the space station to set up for a rendezvous with the outpost tomorrow, when the craft will continue all the way to berthing if NASA gives a "go" after reviewing data from today's testing.

 

[orb]

NASASpaceflight: Dragon completes ISS fly under comm test ahead of berthing opportunity

 

[N_Molson]

Strobe light turned off.

The demo flyby of the ISS has been validated as successful. Proceed with grappling tomorrow

 

[IronRain]

SpaceX Dragon COTS 2 ISS flyby timelapse

[ame="http://www.youtube.com/watch?v=AbTzrU-FpMw&feature=g-u-u"]SpaceX Dragon COTS 2 ISS flyby timelapse - YouTube[/ame]

 

[orb]

Here's calendar event for tomorrow's arrival and capture of the Dragon at the Space Station.

 

[orb]

Aviation Week: Dragon ISS Rendezvous Rehearsal A Success

Parabolic Arc:

• Dragon Completes Station Flyby, Rendezvous and Berthing Attempt Next
  
  
• NASA TV Schedule for Dragon Rendezvous and Berthing

 

[Codz]

Sounds like they're good to go.:thumbup: