Who TransDigm buys from and sells to
Owns dozens of niche aircraft-part makers, mostly sole-source, and earns most profit on spare parts.
Part of Commercial Aerospace and the Aftermarket spending
Buys from 1
- Specialty metals and electronics vendorsalloys, castings and components for its parts
Sells to 4
- BoeingBAproprietary components for new aircraft
- AirbusEADSYthe same, on the A320 and A350
- Airlines and MRO shopsreplacement parts~55% of FY2025 sales from aftermarket (FY2025 10-K)
- US Department of Defensespare parts for military aircraft
Where the chain could break
- ~90% of sales from proprietary, often sole-source parts; pricing draws DoD scrutiny
- Aftermarket earnings track airline flight hours
Competes with
- HEICOHEIcheaper PMA replacements for its parts
- Parker HannifinPHaircraft components
- HoneywellHONaerospace components and aftermarket
Mapped by hand from filings and company reporting, as of October 2026. It shows the relationships that matter most, not every contract: most are never disclosed, and agreements change.