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CASE FILE 003 / INTEGRATION FAILURE

Lost in translation. Somewhere near Mars.

PRIMARY SOURCE LINKED · ABOUT 3 MIN

Two teams. Two unit systems. One spacecraft that never came home.

Incident dateSeptember 23, 1999
mission lost1 spacecraft
CollectionTechnology failures
event_sequence / CASE 003September 23, 1999

FOLLOW THE FAILURE

How a fault became an incident.

A condensed sequence, not a minute-by-minute reconstruction.

  1. 01
    THE TRIGGER

    Different unit conventions

  2. 02
    THE FAILURE SPREADS

    Trajectory data misinterpreted

  3. 03
    THE CONSEQUENCE

    Mission lost

  4. 04
Source record: NASA · Mission overview ↗
THE CRITICAL BREAK

Trajectory data misinterpreted

Explicit units and interface checks make an agreement executable rather than relying only on shared understanding.

Editorial interpretation of the failure pattern.

01 / THE INCIDENT

What happened

NASA lost contact with Mars Climate Orbiter as it approached the planet. The mission was intended to study the Martian atmosphere and relay communications.

Evidence: NASA · Mission overview ↗

02 / THE FAILURE CHAIN

Why it happened

Ground software supplied force data in English units where metric units were expected. The mismatch corrupted trajectory calculations.

QUESTION FOR YOUR TEAM

Which important value crosses a team boundary without a checked unit or range?

03 / THE AFTERMATH

Recovery—and its limits

The spacecraft was not recovered. The investigation turned attention to interface agreements and verification across teams.

04 / TAKE IT WITH YOU

Where could the chain break?

Safeguards to investigate—not a claim that one change would certainly have prevented this incident.

01
SAFEGUARD 1Make units explicit in data contracts.
02
SAFEGUARD 2Validate assumptions across organizational boundaries.
03
SAFEGUARD 3Investigate small discrepancies before they accumulate.

Go to the source.

A condensed editorial account. The lessons are our interpretation, not quotations. Consult the primary source for the full technical record.

NASA · Mission overview ↗
Practice your response ↗
Compare this failure with another ↗

ONE QUESTION BEFORE YOU GO

Where should the meaning of a value be checked?

TAKE IT TO YOUR TEAM

Which important value crosses a team boundary without a checked unit or range?

next_step.txtREAD → PRACTICE

TAKE THE LESSON FURTHER

Check the agreement.

Which interface assumption has never been tested?

The rehearsal is fictional; the case is historical. The review starts with unanswered questions.

CONTINUE THE CONNECTION

TRAIL 03Assumptions at the boundary.Three cases, one recurring question ↗