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Line Maintenance vs Base Maintenance Which do you think demands more skill or experience? For Licensed Engineers, both line maintenance and base maintenance play crucial roles in ensuring aircraft safety and performance. Line Maintenance: Quick turnaround, problem-solving in real-time, fast-paced environment at the gate, often with tight schedules. Immediate results but high-pressure situations. Base Maintenance: Deeper inspections, overhauls, and repairs in a controlled environment. More time for detailed work but longer project timelines. Which do you prefer and why? Let me know your thoughts in the comment! #Aviation #LicensedEngineering #AircraftMaintenance

In response to numerous reports of Lycoming Engine in-flight engine shutdowns risks of "...uncontained engine events..." (a softer term for catastrophic failures) the FAA has issued an Airworthiness Directive 2024-21-02 which will affect an astonishing 16,000 Customers. Unfortunately, the cost to each customer affected by this Airworthiness Directive will be thousands of dollars for every inspection to ensure the continued safety and airworthiness of affected Lycoming engines. The Federal Aviation Administration (FAA) has issued a new airworthiness directive (AD) affecting Lycoming engine models with specific connecting rod assemblies. This was prompted by a series of reports of con rod failures that caused uncontained engine breakdowns and in-flight shutdowns (IFSDs). The directive mandates routine oil inspections to identify bronze metal particles, a potential indicator of connecting rod degradation. If any particles are detected, mechanics must perform additional checks on connecting rod bushings for signs of damage, misfit, movement, or excessive wear. Replacing compromised bushings with approved parts is required to prevent flight risks. According to the FAA, around 16,000 engines on US aircraft, including popular IO-360 and O-320 models, fall under this directive. Inspections and potential bushing replacements are projected to incur significant costs, with estimates placing oil inspection expenses at approximately $235 per engine, connecting rod bushing inspections at $85, and bushing replacements at around $762 each. For U.S. operators, the AD could result in roughly $3.76 million for oil inspections, $1.36 million for bushing inspections, and around $12.19 million for part replacements. The manufacturer’s analysis concluded that certain connecting rod bushings installed between 2009 and 2017 were manufactured below specification, specifically in terms of outer diameter (OD). This substandard sizing leads to reduced retention in the connecting rod, allowing the bushing to shift within the rod assembly and suffer wear from piston forces. This misfit accelerates part failure, risking uncontained engine events. The directive is set to take effect December 5, 2024. It does not specify an oil change frequency, so inspections can continue on each operator's maintenance schedule. Oil filters are typically evaluated at each oil change regardless of the AD, so it should not cause too much hassle unless anything concerning is found. Given the significant risks posed, the FAA deems this AD essential for maintaining operational safety across affected Lycoming-powered aircraft. FMI:  https://lnkd.in/g7Va8Q3z.

Aviation Maintenance Magazine – Commercial Pitot Static testing procedures and the benefits of using semi-automated Air Data Test Equipment Pitot Static Testing on the Flightline Years have gone by without significant advancements in the more commoditized testing functions of aircraft. Old faithful still rings true for most wrench turners grinding it out everyday to play their part in the safest aircraft regulatory environment ever. For aircraft transponder and pitot-static system tests, as required by FAR 91.411 and 91.413, these certifications cannot be performed using automation. The inspector is required to perform leak checks and accuracy verification by commanding the air data test set to each set of the required set point, then visually verify the readings on the instrumentation and readouts. But, wouldn’t it be nice to perform some of these functions at the same time, thereby saving an immense amount of time as compared to sequential testing operations with limited equipment. The use of semi-automated pitot static test equipment offers significant advantages over manual testing methods for commercial aviation and maintenance repair organizations. Pitot static systems are critical components of aircraft, providing essential data for airspeed, altitude, and vertical speed measurements. Additionally, some newer aircraft equipped with SmartProbes can test other parameters, such as Angle of Attack (AoA). Ensuring the accuracy and reliability of these systems is paramount for flight safety and regulatory compliance. And doing them all simultaneously is a huge time-saver for the maintenance teams at MROs around the globe. Read the full article just published in AVIATION MAINTENANCE MAGAZINE below https://lnkd.in/ekm9HKsy SUBSCRIBE via https://lnkd.in/dZ74GvhG   ✈ Aviation Maintenance Magazine is proud to remain one of the very few dedicated MRO publications still being published in print and you can always see the latest digital issue via www.avm-mag.com/current or for All back issues see https://lnkd.in/ghY8kwyw Richard B.

This Airbus article provides a description of best practices that maintenance crews can apply when performing the landing gear servicing tasks, especially fluid and gas. Shock absorber servicing ensures that the shock absorber has the correct gas pressure and quantity of hydraulic fluid. Incorrect servicing of the shock absorber can have the following consequences: 1. If the shock absorber is too stiff, (overserviced fluid or gas) the vibrations and landing forces will excessively propagate to the aircraft structure combined with poor shock absorbing performance on landing (excessive bounce). 2. If the shock absorber is too soft, the shocks can bottom causing damage to parts of the landing gear and the aircrame structure. 3. Use the shock absorber temperature, (never use the ambient air temperature) to determine the correct gas pressure. Using the wrong temperature value if different, will negatively affect the oleo servicing. 4. Do not service a landing gear for at least two hours after the last flight to reduce fluid/gas emulsion and permit more even landing gear temperature. 5. Due to “stiction”, it is recommended to perform the oleo servicing task with aircraft on jacks. This will ensure accurate and efficient servicing of the shock absorber fluid level and nitrogen pressure. 6. After refilling the shock absorber with fluid, the nitrogen needs to be extracted from the mix of new hydraulic fluid with older fluid, which contains dissolved nitrogen molecules due to the gas dissolution effect (foaming). 7. After refilling the shock absorber with hydraulic fluid, it is compressed to check the quantity. Initially, the fluid is likely emulsified meaning “foamy” hydraulic fluid which must be purged so the fluid contained in the oleo is completely clear, just as it comes out of the can. 8. Hydraulic fluid needs to be added and the shock absorber compressed again, repeating these steps until there is no more foam released (clear hyd fluid). It is harder to remove emulsified hydraulic fluid from the shock absorber with the aircraft weight on wheels, and more likely to produce foam in the fluid, making the procedure more difficult to perform. Not recommended.

📑Using unapproved GSE or tools can lead to serious safety issues in aircraft maintenance and operations. The article stresses the necessity of relying on approved suppliers to prevent such incidents. https://lnkd.in/dqsN-yAS

Maintenance personnel play an important role in ensuring the structural integrity of aircraft. This toolbox talk dives into the topic of carbon monoxide and discusses different ways potential leaks can be mitigated. Read more in Flight Safety Australia: https://lnkd.in/eqF3yn2B #MaintenanceMonth #Aviation #Engineering

Lets talk about the CDCCL (Critical Design Configuration Control Limitation) today: 👉🏻 In aviation, CDCCLs are specific limitations that are identified in the design of an aircraft to ensure that the critical design features and configurations, which are crucial for the safe operation of the aircraft and are maintained throughout its operational life. 👉🏻 The primary goal of CDCCLs is to preserve the integrity of the aircraft's fuel tank system, particularly in preventing ignition sources that could lead to fuel tank explosions. Key points about CDCCLs in aviation: 1️⃣ Purpose: To prevent any unauthorised modifications or deviations that could compromise the safety of critical systems, especially the fuel tank. 2️⃣ Documentation: CDCCLs are documented in the aircraft maintenance manual and other relevant technical documents. 3️⃣ Compliance: Aircraft operators and maintenance personnel must adhere to CDCCLs during maintenance, repair, and modifications to ensure continued airworthiness. 4️⃣ Inspection: Regular inspections and audits are conducted to verify compliance with CDCCLs. Overall, CDCCLs are essential for maintaining the safety and integrity of aircraft by controlling design configurations and limiting changes to critical systems.

The aircraft c check is considered part of the "heavy maintenance" portion of aviation maintenance. The C Check happens between 18 months to two years (depending on the aircraft). This is likely performed in a special facility, taking 1-2 weeks. During a C. Check, an aviation maintenance technician performs an extensive check of individual systems and components for serviceability and function. Here are some examples of C Check items, per Aviation Pros: Visually check flight compartment escape ropes for condition and security Check operation of DC bus tie control unit Visually check the condition of entry door seals Operationally check flap asymmetry system Pressure decay check APU fuel line shroud Inspect engine inlet TAI ducting for cracks Inspect stabilizer attach bolts Inspect floor beams Detailed inspection of wing box structure

A recently issued report by Australian Transport Safety Bureau (ATSB) highlighted an event that occurred on 27 May 2022, where a Singapore Airlines Airbus A350-941, registered 9V-SHH, was being preparing for push back when a refueller on an adjacent bay informed the licensed aircraft maintenance engineer responsible for the aircraft turnaround that the pitot probe covers were still fitted. If the aircraft had departed with covered pitot probes, the flight crew would have to deal with erroneous or absent airspeed indications. The contributing factors highlighted by the report include: 1.      The licensed aircraft maintenance engineer certified for the removal of the pitot covers in the technical log and removed a warning placard from the flight deck without visual or verbal confirmation that the pitot covers had been removed. 2.      The contracted MRO had not yet implemented a previously proposed and accepted method to account for tooling and equipment (such as pitot probe covers) prior to aircraft pushback. 3.      Maintenance personnel responsible for the aircraft departure did not conduct a final aircraft walk-around inspection. That inspection was the last procedural opportunity to identify that the pitot covers had not been removed. Hence a combination of personnel and organizational factors could have contributed to unsafe flight. On one hand where the event demonstrates how assumptions, procedural omissions can lead to unsafe conditions, it also highlights that all line personnel (such as the refueller in this case) have a safety role and should always speak up if they see or feel that something is not right. #Aviation #Safety #ATSB #Safetyculture

🔧Hot Section Inspection on PAC750XL Aircraft🔧 Proud to share insights from our recent Hot Section Inspection (HSI) on the PAC750XL, powered by the reliable PT6A-34 turboprop engine. This critical maintenance procedure ensures the longevity and efficiency of our engines by meticulously examining and addressing any wear or damage in the high-temperature components. * Key Highlights: • Proactive Maintenance: Identifying issues early to prevent costly repairs. 💡 • Safety First: Ensuring safe and efficient engine operation. 🛡️ • Optimal Performance: Maintaining peak engine performance. 🚀 * Inspection Procedures: • Disassembly: Opening up the engine’s hot section to access key components. 🔧 • Visual Inspection: Checking turbine blades, combustion chamber, and other parts for cracks, wear, and overheating. 🔍 • Non-Destructive Testing (NDT): Using techniques like dye penetrant and borescope inspections to detect hidden flaws. 🕵️♂️ • Repair/Replacement: Repairing or replacing any damaged components. 🛠️ • Reassembly and Testing: Reassembling the engine and conducting performance tests to ensure everything is in perfect working order. ✅ Regular HSIs are essential for keeping our fleet in top condition and ensuring the highest standards of safety and reliability. 🚀✈️ #Aviation #Maintenance #Safety #Engineering #PAC750XL #PT6A34 #AviationMaintenance