24 October, 2005

1
AMS On-Orbit Operations Philosophy Changes
Prepared by Paul Nemeth ESCG AMS Project Manager

• 24 October, 2005

2
The Issue

• AMS was originally designed with multiple
  decision points that allowed for return and
  repair of AMS subsystems
• The present plan to discontinue Shuttle
  Operations by the end of 2010, delays in the
  re-flight effort post-Columbia, and limited
  number of flights remaining on manifest, make the
  return of AMS is far less likely and the
  requirement to maintain schedule even more
  essential
• This potentially opens the door for simplified
  planning efforts
• Potential changes to integration and design
  requirements
• And for re-prioritization of design constraints

3
Items that should be revisited

• Go/No Go Decisions
• Level of (or at least priority of) Payload
  Checkout during Shuttle Operations
• Powered return capability

4
Go/No Go Decisions

• Go/No Go, Prelaunch at L-9 minutes
• This call is required for safety and cannot be
  removed
• Go/No Go, Prior to AMS removal from Shuttle
  Payload Bay in preparation for transfer to ISS
• What level failure would be required to call a No
  Go for transfer?
• Is there a condition that could delay but not
  cancel transfer operations?
• Stay/No Stay after AMS Checkout on ISS prior to
  STS Undock
• What level failure would be required to call a No
  Stay condition?
• Return to STS would mean return to earth.

5
AMS Checkout in STS

• Extensive Checkout activities have been planned
  on-orbit prior to STS docking with ISS
• Primary purpose of this checkout was to ensure
  AMS health prior to transfer to ISS
• Operation on STS will still be required for
  thermal conditioning if nothing else, but
• How critical is this operation now?
• Would it be better to lower priority on this
  activity and integration effort to push other
  more essential activities?
• Is there something to be gained here?

6
Other Changes

• Powered return capability ROEU is less critical
  now than it was with other requirements
• NASA/JS has already designed a foldable ROEU
  bracket per request of the ISS Payloads Office

7
AMS-02 ROEU / PDA EVA Folding Conceptual Design
PDA
PDA bracket in deployed position (Orbiter
engagement)
8
PDA in Nominal Configuration (Top View)
Point of rotation
PIP pins
9
PDA in Folded Configuration(Top View)
PIP pins
Hit me
10
Recommendation

• A splinter should be arranged during the TIM to
• Revisit these requirements, and identify any
  others that may be impacted by new manifest
  philosophy
• Determine if these items should be removed from
  planning effort
• Or, if priorities should be re-evaluated to allow
  other more essential work to take priority