NASA STS-121/ULF1.1 FD 06 Execute Package
MSG 045 (13-0638) – FD05 MMT SUMMARY
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Page 1 of 4, MSG 045 (13-0638)
FD5 MMT Crew Summary
The focus of the FD5 MMT was a continued review of the TPS areas that were part of the FD4 focused inspection. The good news is that the RCC has been cleared for entry based on the data obtained by you so your hard work has paid off. Here’s a summary of the TPS analysis that has been completed to date.
a)Tile Analysis/ET Doors -No new data on the tile or ET doors since they were cleared for entry at the MMT yesterday.
b) RCC Analysis – As expected the MMT has declared that the RCC is safe for entry based on analysis of the nosecap, Panel 9R, and 5R FD4 focused inspection data. Panel 9R and the nose cap have both been determined to be surface deposits. The nose cap is likely bird dropping (Figure 1) and the Panel 9R data (Figure 2) is thought to be a hydrocarbon source from the booster sep motor or from the launch pad environment. Panel 5R (Figure 3) is thought to be some slight scratching of the RCC coating and is of no concern. For all three of these areas of interest the weave pattern is visible, and there are no damage characteristics such as crushed coating etc. that indicate real damage. There should be no further discussion of the RCC until the late inspection is performed on FD11 and FD12.
d) Gap Fillers – Yesterday the port wing aft gap filler was cleared for entry and today the arrowhead tadpole gap filler has been cleared as safe for entry based on the FD4 focused inspection data. For this gap filler shown in Figure 4 the rooster tail end stitching appears to be damaged/missing and fabric has started to fray. There are no signs of gap filler debond from the tile sidewall and the maximum height of fraying does not appear to exceed 0.20″. The concern yesterday was that this gap filler could trip the boundary layer early on the forward part of the vehicle, thus a focused inspection was required to better analyze the protuberance height. Based on the focused inspection data, the frayed 0.2 inch protrusion height will not effect nominal transition, so this gap filler has been cleared for entry.
This leaves the gap filler forward of the starboard ET door (Figure 5) as the only final concern for entry. Thermal, aerothermal, and stress analysis for that gap filler is planned to be completed for the FD6 MMT. The focused inspection data shown in Figure 5 is greatly assisting the analysis and the team is looking at how much the gap filler will deflect aft during entry. Previous flight data has been reviewed and there have been two prior flights with protruding gap fillers in this area. In fact STS-114 had a .25 inch protruding gap filler in a similar location. The FD6 MMT will review the final analysis and it is expected that this area will be cleared at that time.
e) Thermal Blankets. The two blankets on the upper surface just aft of the F1U and F3U thrusters and the blanket on the port side just forward of the -Y star tracker are still under review in terms of debris transport. The Debris Analysis Team continues to perform blanket pull tests, debris transport, and impact loads analysis in order to clear these blankets. The plan is to review both of these items at the FD6 MMT since all of the analysis is not yet complete. Both of these items are very close to be cleared as safe for entry but the final results will be available tomorrow at the FD6 MMT.
Ascent WLE Sensor Data – As discussed earlier there were 6 ascent events on the WLE sensors (3 on each wing) that tripped the noise floor for further evaluation. After a thorough review of the ascent imagery, radar data, and all other sources, none of this data corroborated the WLEIDS indications. There has been no further discussion of review of this ascent data so this is considered closed as well.
DTO 849- Preliminary results from EVA #1 DTO #849 are very encouraging. The motion was less that expected based on pre-flight analysis and the damping of the OBSS/RMS was much greater than expected. In some cases the motion was expected to take about a minute to damp out and the real performance observed today was that it took about 1/4 of that time to damp out. The DTO team is very happy with the data collected today.
