Author Topic: LIVE: Expedition 18 spacewalk - December 23 (Read 63010 times)

anik · « **Reply #160 on:** 12/23/2008 03:36 pm »

Quote from: bobthemonkey on 12/23/2008 01:51 am

Nice view of Soyuz, DC1 and the semi-retracted arrays of Zarya

Progress, not Soyuz.

Quote from: Johnny Rönnberg on 12/23/2008 05:02 am

Did the do the “Panorama-2008” and photography of the 31P?

"Panorama-2008" task was not included in the final variant of spacewalk timeline sent to a crew on December 20th.

Quote from: TJL on 12/23/2008 01:08 pm

Was this the only planned EVA for Expedition 18?

Yes. I wonder why do I update the Schedule of ISS flight events if no one reads it?

stockman · « **Reply #161 on:** 12/23/2008 03:57 pm »

Quote from: anik on 12/23/2008 03:36 pm

Yes. I wonder why do I update the Schedule of ISS flight events if no one reads it?

People DO read it... just not EVERYONE reads it... Keep the good work coming please..

TJL · « **Reply #162 on:** 12/23/2008 04:30 pm »

Sorry, Anik...you do a great job of keeping us informed here.
I should have checked first...

Life_Support_32 · « **Reply #163 on:** 12/23/2008 04:56 pm »

From the ISS On-Orbit Status regarding the KVD:

The spacewalk began at 7:51pm EST, 36 minutes late due to the pressure equalization valve (PEV; Russian: KVD) in the hatch between the spherical SM PkhO (Transfer Compartment) and the DC1 SU (Transfer Vestibule) not opening on electric command (requiring FE-2 Magnus to enter the PkhO for manual cycling of the valve). The EVA ended at 1:29am. Subsequent repressurization of the DC1 from the SM PkhO failed when the KVD valve remained closed, even on an attempt by Sandy Magnus to open it manually from inside. The spacewalkers had to repressurize the DC1 from one of the backup BPN tanks (#7). The hatch could then be opened. The KVD valve suddenly became electrically functional again shortly before hatch opening (the second vestibule hatch, between the SU and the DC1 SO interior, could be opened OK during equalization).

The item of interest is that last statement that the hatch between the SU and DC-1 SO interior could be opened OK. That hatch should not have been closed, which would have allowed the KVD to repress the DC-1. Because that hatch was closed, when the DC-1 was up at a relatively high pressure (i.e. after the 250 mmHg hold during repress), the hatch was forced closed and did not allow the repress. When the DC-1 was at vacuum, the KVD worked, since the hatch had a large negative delta pressure (~14.5 psi). Once they opened the hatch, the KVD worked again.