🚨 Decision Point #10

Service Module Jettison Timing

⚠️ The Situation

  • Re-entry is hours away — the dead Service Module must be cut loose first
  • The SM shelters the CM's heat shield from the deep cold of space — nobody knows what a long cold soak might do to it
  • No one has seen the blast damage yet — photos would be gold for the accident investigation
  • The crew gets exactly one chance at separation
  • If it goes wrong, a 25-ton module drifts loose right beside the crew

⏰ LATE JETTISON

Keep the SM until about 1 hour before re-entry

✓ Advantages

  • Shelters the CM's heat shield from deep-space cold as long as possible
  • Less time for anything to go wrong after separation

✕ Disadvantages

  • Little or no time to photograph the damage
  • If separation fails or the modules bump, almost no time to recover
  • One chance, zero margin, right before the most dangerous phase of the flight

📸 EARLY JETTISON

Release the SM about 4½ hours before re-entry

✓ Advantages

  • Time to photograph the damage for NASA's investigation
  • Time to troubleshoot if the separation goes wrong
  • Clean separation long before the critical entry phase

✕ Disadvantages

  • Heat shield sits exposed to deep-space cold for longer — an unknown risk
  • Seeing the wreckage could rattle the crew hours before the hardest part of the flight
  • Once it's gone, it's gone

🤔 WHAT SHOULD MISSION CONTROL DECIDE?

👆 Choose one of the options above 👆