Story Thesis
The transformation began because Boeing separated Wichita aerostructures in the 2000s as part of a strategy to outsource more manufacturing and reduce capital intensity.
Causal Chain
Wichita divestiture → Spirit grows as independent supplier → 737/other structures remain critical → quality/supply-chain stress → 2024 acquisition agreement → Dec. 2025 reintegrationEconomic Consequence
Boeing reversed a major outsourcing boundary to align its production system, quality management and workforce more directly
Why It Was Hard
Aerospace transitions combine:
- engineering uncertainty;
- certification;
- suppliers;
- workforce;
- fixed assets;
- long customer contracts.
Each decision can create consequences for years after the original design or contract is signed.
Counterfactual
Keeping Spirit independent would preserve supplier separation but leave Boeing dependent on contractual coordination for its most critical 737 fuselage flow.
What Changed in Boeing's Business Model
The transition changed one or more of:
- vertical integration;
- program risk;
- certification authority;
- production rate;
- cash conversion;
- service opportunity;
- contract structure;
- balance-sheet risk.
That causal change is distinct from current program detail.
Evidence
The Boundary of the Firm
The Spirit story is ultimately a question:
Which activities should Boeing own versus buy?
Outsourcing can improve capital efficiency.
Ownership can improve control.
The best boundary changes when:
- technology changes;
- quality problems emerge;
- supplier financial health changes;
- strategic importance increases.
Boeing reached a different answer in 2025 than it did in 2005.