Out of autoclave (OOA) composite curing is the fastest way eVTOL teams turn layups into reliable flight parts – without the cost and complexity of an autoclave. If you’re wrestling with inconsistent quality, long cycles, or audit risk, this guide shows how to spec, qualify, and run an oven-based process that delivers repeatable results.
Backed by Despatch applications engineers who support aerospace composite curing every day, we’ll cover the vacuum bag-only method, temperature uniformity, and walk-in oven zoning for eVTOL composites manufacturing.
You’ll leave with a simple checklist and questions to ask suppliers – plus links to proven composite curing ovens and NASA-backed best practices for documentation and process control.
Why eVTOL pushes OOA (and what that means for you)
eVTOL airframes are composite, heavy, but cost-sensitive. Ovens fit production bays, scale more easily than autoclaves, and support larger mixed part families. Including props, fairings, interiors, ducts, and secondary structures. Composites groups are already highlighting the shift toward smart materials/tooling and automated processes to hit rate.
OOA process building blocks (keep it simple, make it repeatable)
OOA is fundamentally vacuum bag-only curing in a controlled oven: stable vacuum, correct ramp/soak profile, and good sensor strategy for parts and tools. NASA’s oven-based OOA/VBO work underscores what matters most—void control, material out-time, and reliable documentation.
- Vacuum integrity: Prove leak-rate and stability across the full cycle; log it continuously.
- Ramp/soak discipline: Follow datasheets, but verify with your own thermal mapping at load.
- Sensor strategy: Use enough part TCs to represent thickness and edges; add tool/air TCs for context.
- Loading discipline: Keep airflow paths open; repeat the same load pattern to protect uniformity.
Uniformity by design (walk-in ovens for aerospace components)
For eVTOL-sized parts, engineered airflow and zoning in a walk-in oven for aerospace components protects your temperature uniformity target during ramps, soaks, and cools. Validate at multiple set-points (e.g., 120–180 °C per your resin) and size the work zone to match real production tooling, not just coupons. That approach mirrors lessons learned in OOA research about keeping voids low while parts scale up.
Energy-smart curing tactics (practical, not theoretical)
OOA often reduces capital and operating intensity compared with autoclaves. Beyond that, consider: lower set-point chemistries where allowed, tighter insulation and door seals, and recipe standardization to reduce re-qual work.
NASA has also explored localized or no-oven approaches, which are useful for insight—even if your qualified aerospace process remains oven-based.
From lab to line (without breaking your audit trail)
Move methodically: qualify on Laboratory Ovens with tight data capture, then scale to production on Composite Curing Ovens using the same recipe logic, sensor plan, and load pattern. Keep lot traceability, vacuum logs, TC maps, and operator actions in one batch report.
Include any post-cure steps for 3D-printed tooling or fixtures in the recipe so audits see a complete trail. NASA highlights the importance of in-process visibility (even exploring in-oven monitoring to catch porosity).
OOA quick-spec table (save it for your RFQ)
| Objective | What “good” looks like | What to document |
| Vacuum stability | Leak-rate proven; alarms and continuous logging | Leak test, vacuum trend, alarm checks |
| Uniformity | Mapped work zone at all set-points with real tooling | TUS reports, TC layouts, load photos |
| Recipe control | Repeatable ramps/soaks; guarded cool-down | Program versioning, audit-ready batch report |
| Material handling | Verified out-time, debulk discipline, clean bag stack | Lot traceability, debulk notes, bagging sketch |
| Scale-up | Same load pattern from lab to line; airflow maintained | Scale-up plan, delta analysis vs. coupon runs |
Questions to ask your oven supplier (copy/paste)
- Uniformity: What band can you guarantee at my set-points with my tooling? Will you witness TUS at FAT?
- Vacuum: How many ports and channels can we monitor per wall? What’s the logging resolution and alarm logic?
- Controls & data: Can I export tamper-evident batch reports with TC maps, vacuum trends, and operator actions?
- Load & airflow: Will you help design load patterns and baffles for mixed eVTOL parts?
- Scale & service: How do we add ports/TC channels later, and what commissioning/training is included?
Where Despatch helps (without the hard sell)
- Size and configure a walk-in composite curing system that holds uniformity at production load. Composite Curing Ovens
- Qualify fast on small runs, then scale with confidence. Laboratory Ovens
- See why regulated manufacturers rely on us. About
- Ready for specifics? Speak with an applications specialist. Contact
Sources & further reading
- eVTOL/composites momentum and industry context.
- NASA Technical Reports Server (NTRS) on OOA/VBO oven processing; scale-up/void control; in-oven monitoring.
Image source by Brian Wangenheim on Unsplash
