NASA STS-118 Execute Package FD11
MSG 113 (15-0985) – FD11 MISSION SUMMARY
Page 1 of 2
Good Morning Endeavour!
Thanks for the great day yesterday! You are an awesome crew!
We are looking forward to the EVA today. As you were briefed last night, the EVA will be shortened so that hatch closure can take place this evening. You will undock tomorrow morning. Landing is being planned for Tuesday. This is all because of the potential threat to JSC posed by hurricane Dean. Dean’s ground track is in MSG 117.
Thanks for your flexibility!
MSG 118 (15-0990) – FD10 MMT SUMMARY
Page 1 of 4
FD10 MMT Summary 1
The FD10 MMT met to review mission progress including a Wing Leading Edge Sensor Team Summary and the final Debris Assessment Team TPS Damage Summary. A significant portion of the MMT was also dedicated to review of mission and MCC Flight Control Team options in the event that Hurricane Dean is a significant threat to the Johnson Space Center next week. The MMT made a key decision to shorten the mission content by one day with landing on FD14 in order to protect for the Johnson Space Center closing as early as FD13 based on the latest predicted storm path.
Transfer Ops: As of the MMT, approximately 76% of the middeck and 79% of the Spacehab transfers are complete. The Space Shuttle and ISS Programs greatly appreciate the tremendous effort by the crew to complete the planned transfer operations.
ISS Comm String 2/DAIU Troubleshooting: The ISS S-band string 2 activation occurred today after reconfiguring an ISS rack LA1D2 wire harness. ISS S-band string 2 is performing nominally and will support ISS operations as the primary system. Detailed DAIU troubleshooting was performed on FD10; including scopemeter measurements of laptop-generated tones. The preliminary indication is that there is a wiring problem between PMA2 and the Lab and not a DAIU problem
EVA Glove Damage: The EVA Project presented the rationale to proceed with EVA 4. The rationale centered on the absence of any evidence from the EVA 3 video or discussions with the crew that suggests an obvious region of concern for a glove cut or abrasion. A review of the video from EVA 3 did not reveal any visible sharp edges or excessive wear events. A review of the processes used in the buildup for all of the primary and backup gloves used on STS-118/13A.1 revealed no discrepancies or changes that could have contributed to the observed Vectran damage.
The prime rationale includes the fact that if Ricks glove damage was caused by wear, the risk is mitigated by Dave and Clay performing EVA 4 with gloves that have been inspected and have no RTV damage. EVA 4 tasks are also less hand intensive than Ricks EVAs, and of course periodic glove inspections are in place. If the damage was caused by a sharp edge, it is less likely that the sharp edge existed at the translation paths common to EVA 3 and EVA 4 tasks. Most of the EVA 4 translation paths are commonly used (airlock and along the truss) and have resulted in no glove damage on other EVAs. The translation across the CETA cart to perform the OBSS OSE task was also used by Clay during EVA 3 and resulted in no damage to his gloves. Finally, to verify that there are no concerns with wear along the translation path, additional glove inspections have been added after long translations.
Window 2 MMOD Impact: The Window 2 MMOD impact is estimated to be 0.125 inches in diameter. Using a typical diameter-to-depth ratio that has been derived from many historical post-landing observations, an estimated depth was computed and compared against allowable MMOD impact depths in two flight regimes. The first flight regime was at peak window loading, which occurs on the outer glideslope on final approach and the other was at peak entry heating. The conclusion reached from the analysis is that the estimated Window 2 impact depth does not exceed the allowable depth in either of the two flight regimes. The analysis is known to include significantly conservative assumptions, which provides additional confidence that this MMOD impact is not an issue for entry.
Wing Leading Edge Indications: The team presented a summary of the sixteen on-orbit Wing Leading edge indications which ranged from 0.5 to 2.0 Gs. The magnitudes seen on STS-118 have been very similar to previous missions although there has been a 50% increase in the number of indications compared to previous flights. This may be attributed to the fact that improvements have been made to the system to provide data simultaneously for both wings for longer periods of time and at colder temperatures. For example, the monitoring time during STS-118 before docking is twice as much as STS-117 and about three times that of STS-116.
Most of the indications, a majority of which occurred on the port wing, were clustered early in the mission prior to and after docking. A few of the wing leading edge indications on previous flights have been correlated to minor impacts found on the wing leading edge panels during post-landing inspections. Many of the other WLE sensor indications from previous flights have not been correlated with anything including thruster firings, other mission events, thermal day/night cycles, etc. Many theories exist as to what has caused an increased number of wing leading edge indications on STS-118 including MMOD and the Perseid meteor activity. However, no definitive correlations were found between the Perseids and the increased indications since half of the indications occurred during Earth blockage. Only a single indication occurred during the Perseids peak with both wings being continuously monitored. Obviously, the MMOD concern is the primary reason for executing the late inspection, which will be performed on FD12.
Debris Assessment Team Summary: The Debris Assessment Team provided an in-depth review of all of the locations on the orbiter thermal protection system that have been assessed over the course of the mission. This includes all protruding gap filler and any OMS pod blankets, OMS pod tile, and lower surface tile damage. This includes: damage aft of ET doors, ET door damages, protruding horseshoe gap filler at starboard panel 22, port RCC panel 20 horse collar, protruding pillow gap filler on right hand wing trailing edge lower surface, protruding pillow gap filler on left wing elevon trailing edge, slightly protruding blanket material just forward of PLTs window, tile damage by window 4, slightly lifted right OMS pod blanket, three protruding gap fillers on port OMS pod, and minor OMS pod tile damages. Obviously, there has been very little concern for the overall TPS except for the one area of starboard tile damage that was the subject of discussion for much of the
mission. The bottom line is that the orbiters entire thermal protection system is ready for entry pending the analysis of the late inspection data. Figure 1 contains an overall summary of the key assessment points for the underside of the orbiter.
Hurricane Dean Preparations: The MMT received a briefing on the latest Hurricane Dean National Hurricane Center forecast track from the Spaceflight Meteorology Group. The projected track places the eye of a Category 4 storm in the Gulf of Mexico on Wednesday, FD15 (See Figure 2). Uncertainties in the forecast may change this prediction by +/- 6 hours. A low pressure system is forecasted to track west across the Gulf of Mexico from Florida to Louisiana. This low pressure system may influence the hurricane to take a more northerly ground track. Additionally, a more northerly track could lead to additional strengthening since the storm could miss the Yucatan peninsula entirely.
JSC Senior Management will be meeting daily to assess the hurricane and will be making decisions appropriately. If the track of the hurricane holds to the forecast, it is expected that JSC will be closed on Monday, FD13, allowing non-mission support personnel to care for their families. All disciplines reporting to the MMT are preparing a list of mandatory support personnel that could support the remainder of the mission from JSC. The flight control team is making preparations to staff accordingly to support mission operations through landing.
With the current forecast information, the MMT directed the Mission Operations Team to protect for a landing one day earlier on FD14. To accommodate this timeline, a shortened EVA 4 on FD11 is under consideration to allow for hatch closure at the end of the crew day on FD11. The ensuing timeline under evaluation would encompass undock, flyaround, and late inspection on FD12, FCS checkout on FD13, and landing on FD14. Currently all 3 CONUS landing sites would be called up to support landing on FD 14 with the priority being a KSC, EDW, NOR landing. This landing site plan can be refined as the hurricane track forecast improves over the next few days.
