The Diamond DA62 is a sophisticated twin-engine aircraft known for its efficiency, modern design, and advanced avionics. Its retractable landing gear system, while generally robust, has its own unique characteristics and potential quirks that owners and maintainers need to be aware of. For DA62 owners in California, Arizona, and Nevada, a deep understanding of these aspects, coupled with advanced diagnostic techniques, is essential for safe operation and efficient maintenance.
At The Aero Center, we have specialized expertise in Diamond aircraft, including the DA62’s complex systems. Our 24/7 maintenance center offers advanced diagnostics and precision repairs for landing gear systems, ensuring minimal downtime for your aircraft. We embody the principle of Authority, with our certified professionals meticulously adhering to Diamond Aircraft’s specifications and all applicable Airworthiness Directives.
DIAMOND DA62 LANDING GEAR SYSTEM OVERVIEW
The DA62 features an electrically-actuated, hydraulically-assisted retractable tricycle landing gear system. This means an electric pump provides the hydraulic pressure to extend and retract the gear, which then locks in place mechanically. The system includes:
- Electric Hydraulic Pump: Generates pressure for gear actuation.
- Hydraulic Actuators: Cylinders that physically move the gear struts.
- Uplocks and Downlocks: Mechanical mechanisms that secure the gear in the retracted and extended positions, respectively.
- Limit Switches: Sensors that detect the position of the gear (up, down, in transit, locked).
- Control Unit/Logic: Interprets pilot inputs and sensor feedback to control the gear cycle.
- Emergency Extension System: Typically a manual hand pump or gravity/aerodynamic extension mechanism.
GEAR SYSTEM QUIRKS AND COMMON ISSUES
While highly reliable, some nuances and common issues in the DA62’s landing gear system (and similar Diamond models like the DA42) include:
- C-Clip Retention on Gear Braces (Critical Maintenance Issue):
- Quirk/Known Issue: A significant Mechanical Service Bulletin (MSB62-051) has been issued for the replacement of retaining rings (often referred to as “c-clips”) on the nose and main landing gear braces¹. Failure of these c-clips can allow the associated rod to slide out, leading to a gear collapse or failure to extend/retract. This has been linked to at least one DA62 gear-up incident¹.
- Owner Tip: This is a crucial pre-flight inspection item. Visually inspect these c-clips for presence and security. Ensure compliance with MSB62-051.
- Hydraulic Pump Actuation During Taxi:
- Quirk: Some owners have reported the hydraulic pump actuating briefly during taxi after landing, even if the gear appears to be down and locked². This could be normal pressure equalization within the system or a slight internal bleed.
- Potential Issue: If the pump runs excessively or frequently cycles, it could indicate a low hydraulic fluid level (without an external leak), an internal leak within an actuator, a faulty pressure switch, or even a mis-rigged downlock switch that intermittently tells the system the gear isn’t fully down and locked².
- Owner Tip: Monitor the frequency and duration of pump cycles. Check the hydraulic fluid level in the reservoir (often in the nose baggage compartment) regularly. Note if any landing gear indicator lights flicker.
- Landing Gear Indicator Light Dimming:
- Quirk: In some Diamond models, dimming the cockpit panel lights (especially at night) can also dim the landing gear and flap indicator lights to the point of being imperceptible³. This can be startling, giving the impression the lights aren’t working.
- Owner Tip: Be aware of the dimmer setting and ensure the gear lights are visible before takeoff and landing, especially at night.
- Emergency Extension Mechanism Blockage/Reset:
- Quirk: The DA62 has an emergency gear extension handle (often a knob or T-handle). If this handle is inadvertently pulled, it can mechanically lock the gear system, preventing normal retraction. Resetting this system typically requires maintenance personnel to push the handle back in and reset the mechanism, often requiring specialized tools or procedures that cannot be done in flight⁴.
- Owner Tip: Be mindful of the emergency extension handle during cockpit cleaning or if children are in the aircraft. Familiarize yourself with the reset procedure from the Maintenance Manual in case it’s accidentally activated on the ground.
- Microswitch/Limit Switch Issues:
- Common Point of Failure: Like any complex mechanical system with sensors, the microswitches that sense gear position can become dirty, mis-adjusted, or fail.
- Symptoms: Intermittent “gear unsafe” warnings, gear not retracting/extending fully, or indicator lights not illuminating correctly.
- Repair: Cleaning, adjusting, or replacing the affected microswitch. This requires precise rigging according to the Maintenance Manual.
- Hydraulic Leaks (Internal or External):
- Problem: External leaks are visible (pink hydraulic fluid). Internal leaks might not be visible but can cause the hydraulic pump to cycle more frequently to maintain pressure, or lead to slow gear actuation.
- Detection: Regular visual inspection for fluid, checking fluid reservoir level, and monitoring pump cycling frequency.
- Repair: Identifying and replacing the leaking component (hose, seal, actuator).
ADVANCED DIAGNOSTICS FOR DA62 LANDING GEAR
Modern aircraft like the DA62 leverage integrated systems for advanced diagnostics.
- Garmin G1000/G2000 Integrated Diagnostics:
- The DA62’s Garmin avionics suite is the central hub for many system indications and alerts. The system’s Maintenance Diagnostic System (MDS) or similar menu can provide error codes and detailed system status that pilots might not see on the primary flight display.
- Troubleshooting: Mechanics can access detailed sensor data, fault logs, and potentially perform system tests through the G1000/G2000 maintenance pages. This can pinpoint issues with specific limit switches, the hydraulic pump, or the control unit.
- Owner Tip: Familiarize yourself with accessing basic system information on the MFD, as this might provide clues to a developing problem. Report all warning messages, even transient ones, to your maintenance provider.
- Structural Inspection of Composite Attachment Points:
- The DA62’s landing gear attaches to the composite airframe. This requires specialized inspection techniques during annuals.
- Techniques:
- Visual Inspection (VT): Meticulous examination of the composite structure around the gear attachment points for any signs of cracks, delamination (bubbles, voids), or impact damage. Pay attention to fasteners for any signs of stress or movement.
- Tap Testing: Gently tapping the composite surface with a coin or small hammer to listen for changes in sound (a dull thud indicates a disbond or delamination). This is crucial for detecting subsurface damage that isn’t visible externally.
- Non-Destructive Testing (NDT): For suspicious areas, an IA may recommend more advanced NDT methods like ultrasonic inspection, thermography, or shearography to fully assess the integrity of the composite structure.
- Importance: Damage to the composite structure supporting the landing gear can have catastrophic consequences. Repairs must strictly adhere to the Diamond Aircraft Structural Repair Manual (SRM).
- Electrical System Diagnostics (for Electric-Hydraulic System):
- As the DA62’s gear system is electrically powered, electrical issues can manifest as gear problems.
- Checks: Voltage drops, current draw of the hydraulic pump motor, integrity of wiring harnesses, and relay function. A common issue leading to DA62 electrical system failure and subsequent engine shutdown was found to be incorrectly wired alternator relays and ECU backup batteries, highlighting the interconnectedness of systems⁵.
- Tools: Multimeters, oscilloscope, and dedicated wiring diagram analysis.
- Hydraulic System Pressure Testing:
- Specialized gauges can be connected to the hydraulic system to monitor pressure during actuation and static holding. This helps diagnose pump efficiency, accumulator issues, and internal leaks.
- Rigging and Adjustment Checks:
- Proper rigging of the landing gear is paramount. Incorrectly adjusted pushrods, cables, or limit switches can lead to incomplete extension/retraction, premature wear, or false indications.
- Procedure: Following the detailed steps in the Diamond DA62 Maintenance Manual, checking gear travel, synchronization, and all mechanical stops.
For Diamond DA62 owners in California, Arizona, and Nevada, understanding the unique aspects of your aircraft’s landing gear system and engaging a maintenance facility with advanced diagnostic capabilities is crucial. The Aero Center’s 24/7 service and specialized expertise ensure that your DA62’s landing gear, and indeed all its complex systems, are meticulously maintained for peak safety and reliability.
The Aero Center is located at William J. Fox Airfield KWJF | Lancaster, CA. Contact us at 209.885.6950 for questions or appointments.
Footnotes:
- Diamond Aircraft Industries. Mandatory Service Bulletin MSB62-051: Replacement of Main Landing Gear and Nose Landing Gear retaining rings. (Issued March 24, 2024).
- Diamond Aviators Forum. “Hydraulic Pump Actuating while taxiing.” Discussion on diamondaviators.net, March 2023. https://www.diamondaviators.net/forum/viewtopic.php?t=8884
- Diamond Aviators Forum. “Landing Gear Indicator Lights.” Discussion on diamondaviators.net, March 2018. https://www.diamondaviators.net/forum/viewtopic.php?t=6339
- X-Plane.Org Forum. “Can’t Raise Landing Gear – Diamond DA62.” Discussion on X-Plane.org, June 2019. https://forums.x-plane.org/forums/topic/183242-cant-raise-landing-gear/
- Aerossurance. “DA62 Forced Landing After Double Engine Shutdown Due to Multiple Electrical Issues.” Analysis of an incident, May 2023. https://aerossurance.com/fixed-wing/da62-double-engine-ifsd-electrical/