NASA STS-116 FD-10 Execute Package
Download EVA 4 Procedures (6.2 Mb PDF)
The FD9 MMT was brief today. The main focus was the EVA 4 strategy and a discussion of whether the EVA should still be performed based on what was learned with the P6 array during EVA 3. The EVA camera bracket and orbiter systems status/anomalies were also discussed. The MMT decided that EVA 4 remains a very beneficial activity and will be conducted on FD10 as planned. The EVA timeline management will be left to the crew and the ops team as briefed to you during the FD9 EVA tag up.
The team was very appreciative of your outstanding work on EVA 3 including the P6 array 8 shake and retract technique.
EVA 4 Rationale – The Station Program provided a summary of the EVA 3 blanket box shake technique and the successful retract to the bay 11 position. While a great deal was learned about the array and wire grommet behavior, there may be additional information to learn during the EVA 4 P6 retraction. The team also requires information as to how the array behaves when retracted for the last few bays near the blanket box. Therefore, by performing EVA 4 we will increase the chance of having both P6 arrays latched down by the end of STS-117/13A.
EVA 4 Bingo Strategy – The overall strategy for EVA 4 is not to exceed 6.5 hours. However, if P6 retraction is in work and proceeding toward success the team may extend at the discretion of the Flight Director and crew. If P6 retraction efforts are finished early (with or without success), the EVA will be allowed to continue for get-ahead tasks to a maximum EVA duration of 4.5 hours. The potential get ahead tasks are the 2B Digital Photography Survey and the FMS blanket reseating. As always the MCC provided you with the details in the FD9 EVA tag up.
Lost EVA Camera – Thanks for the downlink picture of the bayonet bracket with the camera shoe attached. This really helped the team understand that it was not a failure of the bracket/shoe interface or a problem with the release mechanism. The team is working on new torque values for you to use prior to EVA 4 and recommends using the D-Ring as a secondary retention device by tethering the camera. The plan is to leave one of the two Shuttle digital cameras on ISS to increase their inventory. MCC will provide you with the transfer details.
As of the MMT, the camera is in front of the station opening at ~1nm/rev. After the undock sep burn on FD 11 it will be approximately 100 nm in front of the shuttle opening over 50 nm/rev, so there is no concern from a long term relative motion perspective.
DAIU Troubleshooting – The team has a troubleshooting procedure ready, however, due to EVA 4 there is not sufficient room to add it to an already full timeline. The good news is that this procedure will be ready for use on upcoming missions if the failure repeats.
Transfer Status – As of the MMT approximately 71% of the Middeck and Spacehab transfer is complete. Based on our assessment transfer is ahead of schedule.
ISS N2 Transfer – This was completed on FD9 with a total of 49 lbs transferred to ISS.
Cryo Margins – The cryo margins are approximately 2 hours O2 limited for a 13+1 day mission. Since this reflects only 2 deorbit opportunities on each day the team is working to build margin to allow for 3 deorbit opportunities for both EOM and EOM+1 should that be required.
tivity – The solar activity remains at high levels and is similar to what has been noted over the past couple of days. EVA 4 is in a good location in terms of ground track, there are no plans to alter the EVA, and it will be managed within the existing flight rules.
