Electric drive rebuild
Power stage, gate driver, DC bus capacitor, and IGBT replacement on Moog rotary loaders and Brunner CLS-E drives.
Control Loading System Repair
Independent third-party repair of the hardware behind simulator control feel: Moog rotary loaders and Brunner CLS-E electric drives on yoke, rudder, and throttle force-feedback loops, plus legacy hydraulic servo valves on older training systems.
Where Control Loading Sits
Four control-loading architectures
Below are the four control-loading architectures and the servo drives or servo valves that come off them for rebuild.
01
Electric (modern)
Moog rotary loaders and Brunner CLS-E brushless servo drives with integrated electronics. Programmable force profiles on yoke, rudder, and throttle.
02
Hydraulic (legacy)
Moog and Parker D1FP servo valves driving hydraulic actuators on older simulators. Common on platforms built before 2010.
03
Hybrid systems
Mixed architectures with electric yoke and hydraulic rudder, or vice versa, often after partial retrofit work on aging simulators.
04
Custom & specialty
Parker and Kollmorgen drives in custom integrations and university trainers. Specialty force-feedback rigs on research and engineering simulators.
What NC Servo Does
Component-level repair on control-loading hardware
Same shop, two technologies. Electric drives and hydraulic servo valves both come through the bench. Component-level rebuild and verification on the same hydraulic and electronic stands.
Servo drive mechanical work
Bearings, encoders, and winding repair on the brushless servo units used in electric force-feedback systems.
Hydraulic valve repair
Spool, sleeve, pilot stage, and torque motor work on Moog, Parker, and Rexroth servo valves on legacy control loaders.
Bench testing
Hydraulic test stands for valve verification and electronic test setups for drive and servo unit performance characterization.
Donor parts service
Stock is hit or miss, but legacy electric drives and discontinued hydraulic loaders show up often enough that we can pull from past jobs when we have a match. Ask about a specific part number.
Repair scope
Hardware repair only. PLC programming, control-feel tuning, and simulator qualification stay with the customer or training-center integrator.
Brands
Control loading brands serviced
Top brands across electric and hydraulic control loading. Click through for the dedicated brand page.
Common Faults
What usually shows up on control-loading hardware
Control loading systems run continuously through every training session. Failures fall into four categories across the electric and hydraulic technologies seen at the bench.
| Drive electronics | Failed IGBTs, blown DC bus capacitors, gate driver damage on electric loaders. Often follows a power-event or cooling-fan failure on the simulator cabinet. |
|---|---|
| Mechanical wear | Worn bearings on brushless servo units, encoder damage from wiring strain, and winding insulation faults after extended service. |
| Hydraulic servo valve | Spool wear, contamination scoring, pilot-stage null shift, and torque motor coil damage on legacy hydraulic loaders. |
| Connector and cabling | Damaged connectors at the pilot input, cable strain at the entry point, and contamination on the connector pins after years of cockpit-area service. |
Workflow
From part number to ship-back
Same four-step path through the shop whether the unit came off a CAE Type D simulator or a Brunner CLS-E retrofit on a regional trainer.
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01
Get in touch
Call or email with the part number, simulator make, and a photo of the nameplate if it helps.
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02
Bench review
Tech inspects the drive or valve and runs it on the appropriate stand to confirm what failed.
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03
Cost & approval
We call back with the cost and a rough turnaround. Nothing is started without your sign-off.
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04
Repair, test, ship
Failed components replaced from inventory or off donors, the unit verified under load, and shipped back.
FAQ
Common questions about control loading repair
Application-specific questions. For brand-specific FAQs, see the dedicated brand page in the brand list above.
What types of control loading systems do you repair?
Electric servo drives used in modern systems (Moog rotary loaders, Brunner CLS-E, custom Parker / Kollmorgen integrations) and hydraulic servo valves used in legacy systems (Moog, Parker D1FP, Rexroth 4WS). All come off the bench for rebuild.
Do you work on Brunner CLS-E electric loaders?
Yes. Brunner CLS-E MK II, NG, and the related Brunner servo drives come through the bench for component-level work on the drive electronics, bearings, encoders, and windings.
What about Moog rotary loaders and FCS-2000 / FCS-5000?
Yes. Moog rotary loaders and the Moog FCS series are covered. Drive electronics, mechanical work on the servo unit, and feedback channels all come through the bench. Refer to the Moog brand page for the broader Moog hardware list.
Can you repair legacy hydraulic control loaders?
Yes. Older simulators that use hydraulic actuators with Moog, Parker, or Rexroth servo valves for force feedback are common at the bench. The valve side runs through the same hydraulic stands as the rest of the aerospace work.
Do you provide control-feel tuning or simulator parameter setup?
No. NC Servo handles bench-level component repair on the hardware only. Control-feel tuning, motion-cue parameter setup, and simulator qualification stay with the customer or training-center integrator.
What is the warranty?
One year on parts and workmanship for repairs and rebuilt units. Standard exclusions apply for power surges, contamination, improper installation, and out-of-spec operation.
More from NC Servo
Related repair coverage
The aerospace hub, the related simulator pages, and the brand pages most-tied to control loading systems.
Aerospace hub
Full aerospace coverage: simulators, control loading, motion bases, hydraulic test stands, GSE.
Motion-base repair
6-DOF Stewart platform servo valves on commercial and military flight simulators.
Moog brand page
Moog rotary loaders, FCS series, and D661 servo valves.
Servo drive hub
Full directory of drive brands - Allen-Bradley, Indramat, Yaskawa, Kollmorgen, and more.
Valve repair hub
Full directory of 20+ valve brands with dedicated pages.
Repair vs replace
When component-level repair makes sense versus buying new or rebuilt.
Control feel gone soft? Send a part number
Give us a call or send a part number with the simulator make and the symptom. We'll check the donor pool, suggest a rebuilt match if we have one, and walk through repair or cross-brand options if we don't.