USA SAFER Panel Meeting Minutes October 26, 2000

NC/ Ron Cook, Chris Estrada

ER/Kevin Lewis stated that the Launch/Landing Bags need to be shipped back to NASA/JSC. ER/Gail Steele will prepare the TPS.

The following will be flying on STS-97:

SAFER SED33105900-309, S/N 1005

SAFER Battery SED33105907-305, S/N 1027

SAFER Battery SED33105907-305, S/N 1028

SAFER Battery SED33105907-305, S/N 1030

NC/Ron Cook stated the On-Orbit Stowage Bags need more testing to pass certification.

XA will not fly the bags until a subsystem manager is found to take over the responsibility.

FIAR JSC-ER0028 was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"SAFER S/N 1006 is undergoing repair and retest to support STS-97 (S/N 1006 will not be used on STS-92). SAFER units scheduled for use on STS-92 have successfully passed testing to verify that all Avionics Assembly cable connections are correct."

No input from ER.

FIAR JSC-ER0030 was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"During pre-flight processing for STS-92, Kapton tape was applied to the spare battery captive screws to prevent them from "backing out" and becoming loose and possibly lost. If any of the screws do become lost during flight, the screws from the replaced prime battery can be used as substitutes on the spare battery."

FIAR JSC-ER0031was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"The SAFER stress analyst has determined that landing with the HCM stowage door improperly closed poses no risk to the SAFER hardware. Therefore, no damage was incurred by landing with the doors open on STS-106. The doors are verified closed when stowed for launch. This FIAR is no constraint to STS-97."

ER is still waiting for the official memo from the stress analyst.

FIAR JSC-ER0032 was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"The -305 Cert. battery recently passed this sleep current acceptance test with the same GSE set-up as mentioned above. The problem appears to be unique to S/N 1030 battery with this GSE set-up. The flight batteries to be used on STS-92 were built at the same time as the Cert. battery, which is passing this test. Additionally, the flight units passed all acceptance testing with no anomalies and flew on STS-106 with no anomalies. If this type of corrupted data were encountered during a self-rescue, it would not impact the battery’s ability to supply adequate power to the SAFER. Additionally, dual tether protocol will be used on STS-92."

FIAR JSC-ER0033 was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"Over thirty NSIs have been fired by various SAFER units. Only one instance of the software not identifying the circuit as being open has ever occurred. As part of the investigation, eight previously fired NSI (five still installed in spent pyro valves) were connected to SAFER avionics and all generated “NSI CIRCUIT OPEN” message during self test. The one spent NSI that produced the false reading continues to do so, indicating a physical phenomenon in the NSI is responsible.

The SAFER units for STS-92 were positively verified to have NSI intact prior to launch. Due to the potential for a false positive NSI status reading, the nominal IVA checkout procedures would not positively verify that the NSI had not been inadvertently fired subsequent to the launch. A simple modification to the check out procedure (i.e., opening the manual isolation valve pre-checkout and closing it post-checkout) that would provide an absolute indication of the NSI condition would also result in the loss of a small amount of GN2, if the NSI had been fired. Since a SAFER unit with an inadvertently fired NSI could still be able to support the EVA safely and successfully, the manual isolation valve will not be opened during IVA checkout in order to preserve the propellant level for EVA."

FIAR JSC-ER0034 was dispositioned as not being a constraint for flight for STS-97 based on the following rationale:

"The thermistor of the certification battery also has this condition, yet it passed QAVT and QATT. All the flight units for STS-92 passed all acceptance tests, flew successfully on STS-106, and have passed ground checkout tests. Failure of the thermistor solder joint on orbit would only cause an incorrect battery temperature reading to be displayed on the HCM, which would not impair the battery’s ability to power SAFER during a self-rescue or during the planned DTO."

FIAR JSC-ER0035 has been dispositioned with the following non flight constraint rationale for STS-97:

"No remedial action is required. All the flight units for STS-92 passed all acceptance tests, flew successfully on STS-106, and have passed ground checkout tests. If these variations in current and voltage were to occur on STS-92, they would not impair the battery’s ability to power SAFER during a self-rescue or during the planned DTO.

Current variations will not be visible to the crew and will have a minimal effect on the % power remaining display on the HCM, because the current variations are averaged out in the calculation. Voltage variations may be noticed by the crew on the HCM, but these variations are small (+/- 0.3 Volts) and have no effect on the % power remaining calculation."

No input from ER.

No change.

No change.