Fatigue Testing of New Stealth Fighter Aircraft
Project name: Fatigue Testing of New Stealth Fighter Aircraft
A Chengdu-based aircraft manufacturing company procured nearly 3,000 channels of SE-86H high-speed static stress-strain testing systems in two batches (2011 and 2013) to conduct static/dynamic loading tests and fatigue characteristic evaluations for a new stealth heavy fighter aircraft.
1. Test Objectives and Key Challenges
(1) Full-Scale Fatigue Testing
Purpose: Validate structural integrity under long-term cyclic loads (simulating 2-3x design service life).
Critical Components:
Stealth-coated airframe (fatigue behavior under radar-absorbing material constraints);
Weapon bay doors (high-cycle fatigue from repeated openings);
Wing-root joints (critical load paths under maneuver loads).
(2) Static/Dynamic Loading Tests
Static Tests: Apply ultimate loads (e.g., 150% limit load) to verify failure modes.
Dynamic Tests: Simulate real-flight spectra (e.g., gust, catapult launch, arrested landing).
2. SE-86H Testing System Capabilities
(1) High-Density Data Acquisition
3,000+ channels for synchronized strain/stress monitoring across the entire airframe;
1Hz–5kHz sampling rates (capturing both slow creep and impact events).
(2) Stealth-Specific Adaptations
Non-contact strain measurement (avoiding damage to radar-absorbent coatings);
EMI shielding to prevent interference with onboard stealth systems.
(3) Automated Load Sequencing
Programmable multi-axis loading (axial/torsional/bending) to replicate complex flight regimes.
3. Test Methodology
Block Loading: Accelerated testing using condensed load spectra;
Crack Monitoring: Acoustic emission + DIC (Digital Image Correlation) for early flaw detection;
Residual Strength Tests: Continue loading post-crack initiation to assess damage tolerance.
4. Engineering Outcomes
Identified critical fatigue hotspots (e.g., modified bulkhead designs);
Extended predicted service life by 25% through material/process optimizations;
Supported rapid design iterations (e.g., reduced testing cycle time by 40%).
Significance: This program established China's first complete stealth-airframe fatigue database, directly enabling the aircraft's 8,000+ flight hour service life certification. Future work will integrate digital twin and AI-based predictive maintenance technologies.
Conclusion
The comprehensive fatigue and static/dynamic testing program successfully validated the structural integrity and durability of the new stealth fighter aircraft under extreme operational conditions. By identifying critical fatigue hotspots and optimizing materials and designs, the program extended predicted service life and reduced testing cycles. This milestone established a complete fatigue database for stealth airframes, supporting future aircraft certification, design refinement, and integration with digital twin and predictive maintenance strategies.
