Aerospace Supply Chain
The Supplier Chain and Its Chokepoints
How the chain is layered, who sits where, and what limits output at each level. The economics invert as you descend: the layer that assembles the most metal earns the least, and sole-source component makers protected by certification barriers earn the most.
| Layer | Economics |
|---|---|
| Airframers | Assembly margin on a decade-long backlog |
| Engines | New engines near cost, then 20 to 30 years of spares and overhaul |
| Systems and interiors | Ship-set content per aircraft plus retrofit aftermarket |
| Aerostructures | The thinnest layer in the chain, and loss-making for six straight years |
| Components and materials | Sole-source positions with aftermarket pricing power, EBITDA margins above 50 percent at the top end |
| Aftermarket and PMA | Undercuts OEM spares pricing on approved alternative parts, and monetises the ageing installed fleet |
| Lessors | Lease rates and portfolio marks, a real-time price on aircraft scarcity |
Supplier Revenue and Operating Margin
The margin inversion in one chart. TransDigm earns 46 percent operating margins on proprietary sole-source parts while Spirit AeroSystems, which builds actual fuselages, runs deeply negative. Switch the metric to compare revenue scale and growth.
What a Broken Tier-1 Looks Like
Spirit AeroSystems was the largest independent aerostructures builder and made healthy margins through 2018. It never earned a profit again after the 737 MAX grounding, and Boeing completed its re-acquisition in December 2025.
Rate Readiness Tracker
Where each programme sits on its rate curve and what is actually holding it back. Almost every target here has moved at least once, so the gate column is the one that matters: Boeing's climb is governed by the FAA and its own wing shop, and Airbus blames engine supply.
Boeing 737 MAX
Constrained- Now:
- 47 per month, not yet stable
- Target:
- 52 per month, no date given
- What gates it:
- Wing production in Renton, then a second line. FAA oversight capped output at 38 after the January 2024 door-plug blowout, raised it to 42 in October 2025, then moved to performance-based oversight in March 2026. Boeing cleared the FAA capstone review in May 2026 to reach 47, but said on Sep 16 it is not yet stable there because wing flow has not improved as expected. Moving to 52 also needs the new North Line in Everett certified and producing. Boeing's Q3 2026 10-Q now expects to stabilize at 47 in 2027, then move to 52.
Airbus A320 family
Slipping- Now:
- Ramping toward rate 75
- Target:
- About 70 by end 2027, stabilising at 75
- What gates it:
- Engine supply. Airbus has publicly blamed Pratt & Whitney deliveries for the stall and has stood up a tenth final assembly line, including a second at Mobile, Alabama, to hold the curve.
Boeing 787
Slipping- Now:
- 8 per month, stable
- Target:
- Next increase beyond 8 planned to begin in December 2026
- What gates it:
- Assembly capacity and supply chain. Boeing's Q3 2026 10-Q says it delayed the planned rate increase in the third quarter and that later increases depend on its Charleston expansion projects and its supply chain. A $1B North Charleston expansion adds a 1.2 million square foot final assembly line, with roughly 14 per month held out as the eventual ceiling.
Airbus A220
Slipping- Now:
- 44 delivered in H1 2026, about 7 per month
- Target:
- 13 per month in 2028
- What gates it:
- Airbus has not named a constraint. Its H1 2026 results say the ramp-up is ongoing and keep the target at 13 per month in 2028, down from the earlier 14.
Airbus A350
Planned- Now:
- Below target
- Target:
- 12 per month in 2028
- What gates it:
- Aerostructures and cabin equipment, the same interiors and seat certification bottleneck that constrains every widebody line.
Airbus A330
Planned- Now:
- 10 delivered in H1 2026
- Target:
- 5 per month in 2029
- What gates it:
- Airbus names no constraint. The order book was 304 A330s at the end of June 2026, about five years of output at rate 5.
CFM LEAP
Climbing- Now:
- 1,802 engines in 2025, 1,030 in H1 2026
- Target:
- 2026 deliveries up high-teens, raised from about 15 percent in July
- What gates it:
- Structural castings and hot-section capacity. 2025 output was a program record, 28 percent above 2024 and finally past the 2019 peak.
Pratt & Whitney GTF
Constrained- Now:
- 1,055 large turbofans in 2025
- Target:
- Recovery through 2026
- What gates it:
- The powder-metal recall. Inspections take 250 to 300 days per engine and RTX has guided to roughly 350 aircraft grounded on an average day through the end of 2026, which is also what caps new-engine output.
Boeing 777X
Blocked- Now:
- Not in delivery
- Target:
- First delivery 2027
- What gates it:
- Certification, not production. Aircraft are being built and stored while the programme waits on the FAA.
Howmet Engine Products
Airfoils and rings, the casting chokepoint, in one P&L. Third-party sales reached $1.37B in Q2 2026, up 32 percent, with segment adjusted EBITDA margin at 37.7 percent against 33.0 percent a year earlier. Figures are recast for a titanium alloy operation Howmet moved to Engineered Structures in Q1 2026, so full-year 2025 sales are $4.24B.
Howmet by Segment, 2024 vs 2025
Engine Products is more than half the company. Fastening Systems is the other aerospace annuity. Engineered Structures is closer to aerostructures economics. Forged Wheels, mostly truck wheels, was the only segment to shrink.
HEICO Flight Support Group
The PMA, repair, and distribution franchise. Fiscal 2025 sales were $3.12B with $750 million of operating income (24.1 percent margin). Fiscal 2023 sales were $1.77B with $387 million of operating income (21.9 percent margin), as the 10-K segment note prints them.
TransDigm FY2025 Revenue Mix
About 90 percent proprietary products and 55 percent aftermarket, per the 10-K. The bar is the Q4 slide's FY2025 pro forma mix: commercial aftermarket 32 percent, commercial OEM 25 percent, defense 43 percent.
FY2025 pro forma mix (Q4 slide)
- Commercial aftermarket10-K range 30 to 35%
- Commercial OEM10-K range 25 to 30%
- Defense10-K range 35 to 40%
AerCap Owned Fleet by Family
1,413 owned passenger aircraft plus 88 owned freighters at year-end 2025. The A320neo family is the largest owned passenger bucket (433), ahead of the A320ceo family (351) and 737NG (212). Managed aircraft and orders are excluded.
AerCap Lease Spread and Sale Gains
Net spread rose from 7.5 percent in 2024 to 7.8 percent in 2025. Owned-aircraft utilization was 99 percent. Sale gains of $819 million, up from $651 million, are a scarcity signal: used aircraft are clearing above book.