Concept design — Integrating electromagnetic systems into Fighter Jet engine programs

1) Objective (why do this?)

• Improve engine reliability, efficiency, maintainability and control by adding mature electromagnetic subsystems (not to replace the turbofan’s primary thrust source). ResearchGate
  
  

• Create an Indian technology stack (GTRE + HAL + DRDO + industry) that lowers life-cycle cost and enables hybrid or electrified demonstrators later. Aviation International News
  
  

2) High-level architecture (what to integrate)

1. Active Magnetic Bearings (AMB) for high-speed spools (or for test-rigs): reduced friction, no lubrication, longer MTBF; best first candidate for radical reliability gains. MDPI
   
   

2. Electromagnetic blade/stator actuation (smart actuators for IGVs and variable stators): fast, precise vane control to avoid stall/surge and widen stable operating map. Eawag-EMPA Library
   
   

3. Integrated health monitoring using EM sensors: non-contact vibration/tip-timing and electromagnetic eddy current sensors for blade health and rub detection. MDPI
   
   

4. Shaft-mounted motor/generator capability (on demonstrators): allows electrical power extraction for on-board electronics / hybrid trials — stepping stone towards hybrid-electric assist. Aviation International News
   
   

5. Power electronics and embedded controls: radiation/thermal-hardened converters, fault-tolerant controllers implemented jointly with DRDO labs/industry. (Supports AMB and EM actuators.)
   
   

3) Phased integration roadmap (practical, risk-managed)

Phase A — Component R&D & testbed (lab, 12–24 months)

• Build AMB test-rig (bench) and demonstrate magnetic stabilization at engine spindle speeds. Leverage GTRE + DRDO test facilities. ResearchGate
  
  

• Develop prototype electromagnetic vane actuator for a single-stage compressor rig. Test actuator speed, torque, and bandwidth. Eawag-EMPA Library
  
  

Phase B — Rig integration & subsystem certification (24–36 months)

• Integrate AMB + EM actuators on a full-core test engine (ground). Validate dynamic stability, actuation reliability, and EMI/EMC behavior. Add shaft-generator demonstrator. NASA Technical Reports Server
  
  

Phase C — Flight demonstrator & phased rollout (36–60 months)

• Install subsystems on a Tejas testbed (or Il-76 testbed as India has used before for Kaveri trials) for in-flight validation of reliability and control benefits. Wikipedia
  
  

• Use lessons to incrementally adopt subsystems in production engines and new derivatives (Kaveri derivatives / future core engines).
  
  

4) Key technical components — design notes

• Active Magnetic Bearings (AMB)
  
  

  • Requirements: high stiffness, low latency control, thermal management for electronics. Use hybrid AMB (permanent + active) to reduce control load. Proven in turbomachinery literature and NASA programs. MDPI
    
    

• Electromagnetic actuators for vanes
  
  

  • Use high-torque, high-bandwidth actuation placed outside hot gas path when possible; or develop high-temperature tolerant variants for close-coupled vanes. Prior small-engine work shows feasibility. Eawag-EMPA Library
    
    

• Sensors & Structural Health Monitoring
  
  

  • Non-contact tip-timing, eddy-current probes, and electromagnetic vibration sensors to detect early fatigue and enable predictive maintenance (reduce A-checks). MDPI
    
    

• Power & Control Electronics
  
  

  • Hardened, redundant power electronics and control software with EMI mitigation; close collaboration with HAL/DRDO labs and domestic power-electronics firms is vital. Consider modular, swappable control boxes for maintainability.
    
    

• Shaft-mounted generators / hybrid bus
  
  

  • For demonstrators, a shaft generator provides power for actuators and sensors; enables trials of electric fan boosters later. Rolls-Royce/GE hybrid demonstrators show the industry direction. Rolls-Royce
    
    

5) Indian implementation & organizational flow

• GTRE: lead engine-level design, test-rigs, and AMB integration (core competency). Wikipedia
  
  

• HAL: integrate engine subsystems into aircraft installations, flight trials, certification liaison.
  
  

• DRDO: coordinate funded R&D, provide test infrastructure and systems-level validation.
  
  

• Industry partners (private OEMs, PSU suppliers, academia): power electronics, actuator manufacture, controls, and fabrication. Encourage consortium model & Make-in-India supply chain.
  
  

6) Certification & safety considerations

• Demonstrate fail-operational / fail-safe modes: EM actuators and AMBs require deterministic fallback strategies (mechanical locks or redundant bearings for safe shutdown).
  
  

• Rigorous EMI/EMC testing—EM subsystems must not interfere with avionics or sensors.
  
  

• Use progressive certification: bench → ground → flight demo → limited fleet introduction.
  
  

7) Risks & mitigations

• Risk: Thermal and reliability limits of EM hardware in hot engine environment. → Mitigation: place electronics outside hot gas path; use thermal shielding and remote actuators; hybrid mechanical backup. InfoScience
  
  

• Risk: Power availability & weight penalty for EM systems. → Mitigation: start with low-power actuators and AMBs (which save maintenance weight long term); use shaft-generator demonstrators; optimize control for minimal electrical draw. Aviation International News
  
  

• Risk: EMI interference. → Mitigation: strict EMC design, dedicated shielding, and redundant control channels.
  
  

8) First-order benefits (why invest)

• Expanded stable operating envelope → fewer stalls/surges and safer low-altitude ops. SpringerLink
  
  

• Lower maintenance (no lube systems for AMB-bearinged spools), less downtime, long-term lifecycle savings. MDPI
  
  

• Enables hybrid/higher-electrification demonstrators later (electric booster fans, shaft electrical extraction). Aviation International News
  
  

9) Quick costs & resource suggestions (budget framing)

• Start with a modest R&D tranche for Phases A–B (test rigs, prototypes, controllers): can be framed as DRDO/MinDef strategic program with industry cost-sharing. (Precise numbers require detailed BOM and facility costing.)
  
  

• Use existing testbeds (GTRE, HAL flight test platforms) to reduce capital spending. Wikipedia
  
  

10) Immediate next steps (concrete actions)

1. Form a GTRE-HAL-DRDO working group and define use-cases (which spool, which vane, and which test-rigs). Wikipedia
   
   

2. Procure/build AMB test rig (bench demonstration) and an IGV electromagnetic actuator demonstrator. ResearchGate
   
   

3. Partner with domestic power-electronics firms and academic labs (IITs/DRDO labs) for control algorithms and EMI testing.
   
   

4. Prepare an incremental certification plan: bench → ground → flight demonstrator.
   
   

References (selected)

• Reviews on Active Magnetic Bearings and their application in gas turbines. MDPI
  
  

• NASA / academic work on magnetic bearings and turbomachinery (foundational). NASA Technical Reports Server
  
  

• Smart IGV actuation / shape-adaptive blade research (small-engine demonstrators). Eawag-EMPA Library
  
  

• Industry hybrid demonstrations and electric motor development (Rolls-Royce, GE). Aviation International News
  
  

• Current status reporting on Kaveri / GTRE testing and flight test approaches. Wikipedia