BUZZINNOVATION & TECHNOLOGY

Barfield Enters Unmanned Aircraft Maintenance Repair Market in New Agreement with Robotic Skies

Barfield Inc., a subsidiary of Air France Industries KLM Engineering & Maintenance (AFI KLM E&M) in the Americas, is now a Robotic Skies authorized repair station for unmanned aircraft component repair at its Louisville, Ken. facility. Barfield says their 75 years of experience in manned aircraft component repairs will enable them to adapt to the Unmanned Aircraft Systems (UAS) commercial industry with the same high-performance level.

Barfield says with the rapidly growing UAS market, it is “well positioned and ready to adjust its highly trained technicians, engineers and know-how to meet this emerging industry.” Robotic Skies has partnered with Barfield to establish custom made support programs locally for commercial UAS operators to support the rapid growth of this technology.

“Barfield, with this agreement, demonstrates our ability to innovate and continuously reinvent ourselves. We are already equipped with the appropriate test benches and expertise to support UAS. We value this new partnership with Robotic Skies and are very hopeful for the future of our partnership,” says Hervé Page, CEO of Barfield.

“Barfield embodies the forward-thinking organizations we look for as we recruit repair stations into our network,” says Brad Hayden, founder & CEO of Robotic Skies. “Barfield’s breadth and depth of aerospace experience are vital to ensuring that emerging commercial UAS technology is supported and maintained on a par with existing business and general aviation operations.”

AVIONICSINNOVATION & TECHNOLOGY

Garmin Autoland Achieves EASA and FAA Certification on Daher TBM 940

Garmin International Inc., a unit of Garmin Ltd. announced European Aviation Safety Agency (EASA) and Federal Aviation Administration (FAA) certification of Autoland in the Daher TBM 940. The Garmin Autoland system is available as part of the G3000 integrated flight deck and is capable of taking control and landing the aircraft without human intervention in the event the pilot is unable to fly.

“Garmin Autoland continues to gain the recognition and praise of many throughout the world; we are excited to announce yet another milestone – EASA certification of this progressive, forward-thinking technology,” said Phil Straub, executive vice president and managing director of aviation. “As we celebrate this significant achievement in aviation history, I would like to congratulate everyone at Daher, EASA, Garmin and the FAA who have come together and contributed to the development and certification of Autoland, a technology that will have lasting impacts on the safety of the aviation industry.”

In the event of an emergency, the pilot or passengers on board the aircraft can activate Autoland to land the aircraft with a simple press of a dedicated button. Autoland can also activate automatically if the system determines it’s necessary. Once activated, the system calculates a flight plan to the most suitable airport, while avoiding terrain and adverse weather, initiates an approach to the runway and automatically lands the aircraft – without pilot or passenger intervention.

Autoland takes into account a breadth of information and criteria during an activation, including a wide range of performance, operational and environmental factors. The availability of a GPS approach with lateral and vertical guidance to the runway is also required when the system is considering various airports and runways. Even further, the system will automatically communicate with air traffic control (ATC), advising controllers and pilots operating near the aircraft of its location and its intentions.

Throughout an Autoland activation, the G3000 integrated flight deck provides passenger-centric visual and verbal communications in plain language so passengers in the aircraft know what to expect. The flight displays show the aircraft’s location on a map alongside information such as the destination airport, estimated time of arrival, distance to the destination airport and fuel remaining. Airspeed, altitude and aircraft heading are also labeled in an easy-to-understand format. Passengers also have the option to communicate with ATC by following simple instructions on the display using the touchscreen interface on the flight deck.

The Garmin Autothrottle system is used to automatically manage aircraft speed, engine performance and engine power so the aircraft can climb, descend or maintain altitude as needed during an Autoland activation. On approach to land, the system initiates a controlled descent to the airport. If the aircraft needs additional time to descend or slow down during the approach, the Autoland system initiates a standard holding procedure. When aligned with the runway, the landing gear and flaps are automatically extended and the aircraft continues its descent. On the runway, automatic braking is applied while tracking the runway centerline to bring the aircraft to a full stop. Engine shutdown is also automated so occupants can safely exit the aircraft.

At any time, a pilot can easily deactivate an Autoland activation. With a single press of the “AP” autopilot key on the autopilot controller or the autopilot disconnect button on the controls, an Autoland activation can be canceled. The flight display shows a message that confirms Autoland has been deactivated and in the event of an accidental deactivation, the system shows passengers how to reactivate Autoland if needed.

Garmin Autonomí, a family of autonomous safety solutions, encompasses Autoland, Emergency Descent Mode (EDM) and Electronic Stability and Protection (ESP). These technologies add to the safety enhancing tools and capabilities of a Garmin-equipped flight deck. For example, in the event an aircraft loses pressurization, EDM is capable of automatically descending the aircraft to a preset altitude without pilot intervention to help avert hypoxic situations.

ESP further enhances the Autonomí suite by working to assist the pilot in avoiding unintentional flight attitudes beyond that for normal flight. ESP works in the background while the pilot is hand flying the aircraft to help pilots avoid inadvertent flight attitudes or bank angles. Should the pilot become inattentive while hand flying the aircraft and exceed pre-determined pitch, roll or airspeed limitations, Garmin ESP activates and the pilot will feel pressure on the flight controls that guide him/her back to a recommended flight limit.

In addition to certification on the Daher TBM 940, the award-winning Garmin Autoland system has also received FAA certification on the Piper M600 and will soon be available on the Cirrus Vision Jet, with additional aircraft approvals expected to follow. For additional information regarding the Garmin Autonomí family of autonomously activated flight technologies, visit www.garmin.com/Autonomi.

INNOVATION & TECHNOLOGY

Boom Supersonic and Rolls-Royce Agree on New Collaboration for Supersonic Overture Engine Program Design

Boom Supersonic, an aerospace company building a supersonic civil aircraft, and Rolls-Royce, have announced an engagement agreement to explore the pairing of a Rolls-Royce propulsion system with Boom’s flagship supersonic passenger aircraft, Overture.

The goal of the new agreement is to work together to identify the propulsion system that would complement Boom’s Overture airframe. The engagement will involve teams from Boom and Rolls-Royce collaborating in engine-airframe matching activities for Boom’s flagship supersonic passenger aircraft, Overture. The teams will also examine certain key aspects of the propulsion system. The teams will investigate whether an existing engine architecture can be adapted for supersonic flight, while Boom’s internal team continues to develop the airframe configuration.

“We’ve had a series of valuable collaborations and co-locations with Rolls-Royce over the past years to lay the groundwork for this next phase of development,” said Blake Scholl, Boom founder and CEO. “We look forward to building on the progress and rapport that we’ve already built with our collaboration as we work to refine Overture’s design and bring sustainable supersonic transport to passenger travel.”

The priorities of this engagement are informed by Boom and Rolls-Royce’s shared commitment to sustainability. Both companies recognize that supersonic passenger travel has to be compatible with a net-zero carbon future, and the two teams will work together to address sustainability in Overture design and operations. Overcoming the technological challenges of supersonic flight provides a unique opportunity to accelerate innovation sustainably.

“We share a strong interest in supersonic flight and in sustainability strategies for aviation with Boom,” said Simon Carlisle, director of Strategy, Rolls-Royce. “We’re now building on our valuable experience in this space as well as our previous work together to further match and refine our engine technology for Boom’s Overture.” 

As a result of this collaboration, Boom and Rolls-Royce expect to make significant progress towards finalizing Overture’s aircraft configuration and propulsion system.

INNOVATION & TECHNOLOGY

Lockheed Martin Developed Technology that Will Protect NASA’s Mars 2020 Mission

Lockheed Martin developed the technology behind the aeroshell that will protect NASA’s newest Mars rover, Perseverance, and deploy the first-ever Mars helicopter. The Mars 2020 spacecraft with its Perseverance rover is scheduled to launch July 30 from Space Launch Complex-41 at Cape Canaveral Air Force Station on a United Launch Alliance Atlas V rocket.

The Perseverance rover, built by NASA’s Jet Propulsion Laboratory (JPL), will study the geology of Mars while searching for signs of past microbial life, collects samples of rock, and will even set the stage for human exploration to the planet. The 2,260-pound rover is enclosed in an aeroshell capsule that protects the rover during its seven-month deep space flight and atmospheric descent toward the Martian surface. Lockheed Martin built this large aeroshell and every previous NASA aeroshell sent to the Red Planet. 

The mission also debuts the first helicopter designed for another planet, named Ingenuity, to test autonomous flight on Mars. Lockheed Martin was tasked by JPL to build the Mars helicopter delivery system (MHDS) that will deploy the helicopter to the Martian surface for its flight. The delivery system was designed by Lockheed Martin collaboratively with JPL and attaches the Ingenuity helicopter to the belly of the rover. The lightweight system was designed to reliably deploy the 4-pound helicopter to the surface using four pyrotechnic separation events. It also protects Ingenuity from debris during landing with a durable, yet light, composite debris shield. 

NASA’s Ingenuity Mars Helicopter will travel to Mars as part of the Mars 2020 Perseverance Rover mission. Once on the rover is safely on the ground, the helicopter needs to be deployed to the surface to allow it to fly. JPL asked Lockheed Martin Space to develop this system called the Mars Helicopter Delivery System (MHDS). Engineers at Lockheed Martin near Denver developed the unique system and tested it using the Mars Helicopter on loan to the company.

“This mission is pivotal to the future of Mars exploration,” said Lisa Callahan, vice president and general manager of Commercial Civil Space at Lockheed Martin Space. “Our partnership with NASA to build the aeroshell and engineer the Mars helicopter delivery system allowed us to draw upon our deep expertise in aeroshells while also inventing new systems to enable the first flight in the atmosphere of Mars. This all moves us closer to the day humankind will walk on the Red Planet.”

Mars 2020 Heat Shield testing using the NASA Full Field Strain Measurement System

The Mars 2020 aeroshell, along with the one built for the Mars Science Laboratory mission, is the largest built for a robotic mission. Composed of a heat shield and cone-shaped back shell measuring 15 feet in diameter, the aeroshell is constructed in a composite aluminum honeycomb structure sandwiched by graphite-epoxy face sheets. The heat shield is covered with tiles of a protective material called phenolic impregnated carbon ablator (PICA) that can withstand the more than 2,370 degrees Fahrenheit seen during peak heating.

Perseverance is expected to land on Mars on Feb. 18, 2021.

INNOVATION & TECHNOLOGY

Honeywell to Introduce Ultraviolet Cleaning System for Airplane Cabins

Honeywell and Dimer have announced a partnership to bring an ultraviolet cleaning (UVC) system to airlines that, when properly applied, significantly reduces certain viruses and bacteria on airplane cabin surfaces. The Honeywell UV Cabin System can treat an aircraft cabin in less than 10 minutes for just a few dollars per flight for midsize to large airline fleets.

“This offering is a big win for our airline customers, which are seeking affordable ways to clean their cabins effectively and quickly between flights,” said Mike Madsen, Honeywell Aerospace president and CEO. “Honeywell is working on a range of solutions to help make passengers more comfortable about flying.”

Honeywell is accepting orders for the UV Cabin System now with the first shipments coming in July. Pricing will vary based on quantity, but for midsize to large airlines with hundreds or more aircraft, Honeywell’s system could be applied to their aircraft for less than $10 per use.

“Working with Honeywell puts this technology in the hands of a worldwide aerospace leader that can quickly deliver to airlines and other aircraft operators,” said Elliot M. Kreitenberg, co-founder and president of Dimer. “As the travel industry begins to recover, we know hospital-grade technology will ease passenger concerns, and that’s what we’re providing with this system.”

Honeywell says this UV Cabin System is roughly the size of an aircraft beverage cart and has UVC light arms that extend over the top of seats and sweep the cabin to treat aircraft surfaces. Properly applied, UVC lights deliver doses that medical studies find reduce various viruses and bacteria, including SARS CoV and MERS CoV. Results vary based on UV dosage and application, and no testing has been done specifically on protection against COVID-19.

Dimer and Honeywell have entered into a worldwide, exclusive license as part of a strategic partnership for Honeywell to produce, advertise and sell portable UV technology devices for use within the aerospace industry. Honeywell is currently in discussions with multiple airlines and service providers for the UV Cabin System.

UVC has been used in hospitals, air and water filters, microbiology labs, and other applications.

Most household lamps have between 500 and 700 nanometers (nm) of ultraviolet light. In comparison, UVC refers to ultraviolet light with wavelengths between 200 and 280 nm. 

INNOVATION & TECHNOLOGY

Electric Aviation Group Unveils World’s First Hybrid Electric 70+ Seater Aircraft

A pioneering design for a Hybrid Electric Regional Aircraft (HERA) which will deliver a technical and commercial entry point for sustainable mass air transport was being unveiled during the virtual FIA Connect event. The design has been developed by the Electric Aviation Group (EAG), a UK-based engineering and development firm, which expects its first aircraft to be in service by 2028. They call the design “disruptive” and EAG says it has optimized the “latest technology, economics and operational parameters to create the design for the Hybrid Electric Regional Aircraft, to ensure it can solve the challenges of decarbonization and mass transportation.”

The design, which was unveiled to coincide with the opening of the virtual Farnborough Airshow (FIA Connect), has received unequivocal support from EAG’s JetZero consortium, which includes some of the UK’s leading engineering and manufacturing organizations and senior academic advisors.

“Significant investments have been raised to develop sub-19 seat hybrid and all-electric aircraft which we believe is the wrong strategy. These small planes cannot meet the demands of mass air transportation or the requirements of decarbonization,” commented Kamran Iqbal, founder and CEO at EAG. “Our design is for an aircraft that will initially offer 800 nautical miles range at launch in 2028, and which will be able to carry over 70 people. We will be a first mover in what is a $4.4 trillion market.”

EAG says they will draw on the rich heritage and strong aviation industry in Bristol, UK, when it begins production of the new aircraft for which it has already developed and filed a total of 25 patents covering a wide range of technologies. The organization says it expects to create more than 25,000 jobs and unlock $5 billion investments in the UK aerospace industry.

“We expect this to be a great example of British design, engineering and build,” said Iqbal. “Not only will the development of the HERA help the Department of Transport accelerate its ‘Jet Zero’ carbon reduction goals, it will also help to create much needed job opportunities in the aerospace, manufacturing, engineering and services industries post-Brexit. This represents the future of both passenger and cargo flights internationally and as an opportunity for investment, it could not be better timed.”

EAG says their mission statement is “to develop differentiating, disruptive technologies that enable the design and manufacture of 70+ seat hybrid and all-electric aircraft that have a measurable impact on carbon emissions and noise.” Members of the EAG team include CEO Iqbal, a former Airbus and Bombardier executive who holds more than 25 patents (granted and pending) including one for EAG’s proprietary Urban Air Mobility Aircraft concept, Silene; Dr. Norman Wood, chief technology officer who spent nine years as senior post-doctoral researcher at Stanford University also a former Airbus exec; Dr. Behrooz Barzegar  – ex-Airbus – head of Aerodynamics and Flight Physics;Prof. John M Price former VP of Airbus Landing Gear and VP of Energy and Propulsion at EADS Innovation Works and Professor Patrick Wheeler – head of the Power Electronics, Machines and Control Research Group, Global Director of the University of Nottingham’s Institute of Aerospace Technology and is the Li Dak Sum Chair professor in Electrical and Aerospace Engineering.

The EAG says their guiding principles are in response to the EU Flightpath 2050 targets. Those targets include a 75% reduction in CO2 emissions per passenger kilometer, a 90% reduction in NOx emissions and a 65% reduction in perceived noise. Progress during the last 50 years in addressing some of those factors, but EAG says the pace of improvement is slowing and believes it will take new aircraft technology and design to meet those targets.

INNOVATION & TECHNOLOGY

Skyports Partners with Robotic Skies to Develop a UAS Maintenance Program for Drone Delivery and Beyond

Drone delivery service provider Skyports recently announced its partnership with Robotic Skies, the global maintenance, repair, and overhaul network for commercial unmanned aircraft systems (UAS).

Skyports specializes in operating end-to-end drone deliveries within the medical, e-commerce, and logistics sectors. The company is conducting medical drone deliveries to assist the NHS in Scotland in the battle against COVID-19. In addition, as a participant in the UK Civil Aviation Authority’s (CAA) Regulatory Sandbox, Skyports is working to advance regulatory approvals that foster more beyond visual line of sight (BVLOS) operations and the safe integration of these flights into non-segregated airspace – key to realizing a permanent drone delivery service. 

“Certified maintenance is vital to enable full-scale, permanent commercial drone delivery operations,” Duncan Walker, CEO of Skyports, said. “With Robotic Skies, our fleet of UAV systems will be maintained to the same safety standards as traditional certified aircraft. This partnership allows us to further demonstrate our commitment to the safe operation and integration of delivery drones alongside other users of the airspace and supports our plans to grow our service network internationally.”

Robotic Skies, through partnerships with companies like Skyports, provides enterprise UAS and drone delivery fleet operators with local field maintenance services. The company’s proprietary system combines expertise in unmanned aircraft systems and traditional aviation maintenance methodology to deliver high-quality, scalable services. The Robotic Skies Service Center network is comprised of over 200 independently owned and operated certified repair stations, spanning more than 40 countries.

“We are excited to partner with Skyports as they pursue the expansion of drone delivery and other BVLOS flight operations in the UK and beyond,” Robotic Skies founder and CEO, Brad Hayden, said. “Our global Service Center Network puts high-quality support services where Skyports customers need it. Because we are leveraging the existing manned aviation infrastructure, we offer the highest quality, safety, and consistency in our programs to satisfy operators, regulators, and manufacturers.”

Maintenance standards provide an essential framework for the safety and ongoing airworthiness of certified UAS as they evolve to transport heavier payloads, fly longer distances, and carry people within and between urban environments.

Skyports, Vodafone and Deloitte Collab on Drone Deliveries for NHS in Scotland
INNOVATION & TECHNOLOGY

Skyports, Vodafone and Deloitte Collab on Drone Deliveries for NHS in Scotland

Drone delivery service provider Skyports has collaborated with technology communications company Vodafone and digital consultants Deloitte to transport medical supplies and samples for the NHS in Scotland using drones. The live flights will take place later this year and will use mobile connectivity and space-based technology.

The Skyports-led project was selected following a drive to find space-enabled technology and services that can support the NHS response to coronavirus and stop the spread of the disease in a joint funding initiative between the UK Space Agency (UKSA) and the European Space Agency (ESA).

In the coming months, Skyports will start delivering pathology samples, medicine, essential personal protective equipment (PPE) and COVID-19 testing kits between hospitals and to and from medical practices in Argyll and Bute on the west coast of Scotland.

Through Skyports’ technology, pick-ups that currently take up to 48 hours to be transported between healthcare sites will take only 30 minutes and with a much higher frequency.

Etihad and Boeing Extend Partnership with Sustainability-Focused ecoDemonstrator Testing
INNOVATION & TECHNOLOGY

Etihad and Boeing Extend Partnership with Sustainability-Focused ecoDemonstrator Testing

Etihad Airways and Boeing will work together starting in August on the seventh iteration of the ecoDemonstrator program to test innovative technologies in the air, building on the core innovation and sustainability tenets of their strategic partnership signed in November 2019.

Boeing says the “ecoDemonstrator program utilizes commercial aircraft as flying testbeds to accelerate technology development that will make commercial aviation safer and more sustainable now and into the future.” The 2020 program will be the first to use a Boeing 787-10 Dreamliner. It will leverage the Etihad Greenliner program as part of the broader Etihad-Boeing Strategic Partnership to test cutting-edge technologies and explore “blue sky” opportunities to improve airspace efficiency, reduce fuel use, and cut CO2 emissions.

Stan Deal
Stan Deal, CEO, Boeing

“This is the latest program under Etihad’s industry-leading strategic partnership with Boeing, focusing on innovating real-world solutions to the key sustainability challenges facing the aviation industry,” Tony Douglas, Etihad Aviation Group CEO, said.

“When we launched the partnership with the announcement of the Etihad Greenliner program at the Dubai Airshow last year, we promised it was just the beginning of a deep, structural partnership between our two organizations that would go on to lead the industry towards a sustainable future. The ecoDemonstrator program is founded on innovation and sustainability. These are core values for Etihad Airways, Abu Dhabi, and the United Arab Emirates, and Etihad and Boeing see a great opportunity to collaborate and share knowledge to minimize the impact of aviation on the environment.”

Boeing Commercial Airplanes President and CEO Stan Deal said: “Industry collaboration is a key aspect of Boeing’s ecoDemonstrator program that enables us to accelerate innovation. We’re proud to broaden our sustainability partnership with Etihad Airways by testing promising technologies that can reduce emissions, help commercial aviation meet our climate goals, and allow the industry to grow in a responsible manner that respects our planet and its natural resources.”

Boeing and Etihad will work with industry leading partners, including NASA and Safran Landing Systems, to conduct aircraft noise measurements from sensors on the airplane and the ground. The data will be used to validate aircraft noise prediction processes and the sound reduction potential of aircraft designs, including landing gear, that are modified for quieter operations. In addition, a flight will be conducted during which pilots, air traffic controllers and an airline’s operations center will simultaneously share digital information to optimize routing efficiency and enhance safety by reducing workload and radio frequency congestion.

Test flights will be flown on a blend of sustainable fuel, which significantly lowers aviation’s environmental footprint. The testing program is expected to last approximately four weeks before Etihad’s Boeing 787-10 is entered into service in Abu Dhabi.

LUBRICATION CONSIDERATIONS FOR GROUNDED AIRCRAFT By Ed Barnes, Aviation Lubricants Global Chief Engineer, ExxonMobil
INNOVATION & TECHNOLOGY

LUBRICATION CONSIDERATIONS FOR GROUNDED AIRCRAFT By Ed Barnes, Aviation Lubricants Global Chief Engineer, ExxonMobil

The aviation industry is facing a challenging time as travel restrictions persist and airplanes are grounded in an effort to stop the spread of COVID-19. According to fleet data estimates, approximately 9,000 aircraft are now in short-term parked status and more than 3,000 aircraft have been put in long-term storage worldwide.

As airlines grapple with an unprecedented number of grounded aircraft — and for an indeterminable amount of time — preventative maintenance is top of mind. Airlines likely find themselves dedicating an abundance of resources to keep parked aircraft in near ready-to-fly condition, and there are several factors airlines should remain mindful of to help ensure the right measures are taken to safely return planes to the skies when the time comes. Lubrication is one often overlooked but critical aspect.

This article explores lubricant considerations for grounded aircraft, and is intended to be an educational resource. It is essential that airlines follow the instructions included in aircraft OEM maintenance manuals.

Best Practice: Exercise the Engine

When an aircraft is parked for an extended period, there is increased risk for deterioration of its components and structure if preservation procedures are not followed. These procedures include everything from covering windows to preserve the inside of the aircraft, to setting up ventilation and dehumidifiers and covering gaps in the airframe to prevent birds from nesting in the engines.

Not to be overlooked, it is also important to consider “exercising” aircraft engines to bring the oil to operating temperature if possible. This is done to evaporate water and renew the film of protective additives on the surfaces of engine components, and is done weekly, or sometimes every two weeks.

Ester-based aviation turbine lubricants absorb water from the atmosphere at every opportunity. Water contamination will cause hydrolysis of the esters to occur, which forms acids likely to damage engine components. The longer the oil is exposed to the atmosphere, the more water it absorbs, increasing the risk of forming acids.

The rate of water contamination is also dependent on temperature and ambient humidity. Occasionally running engines while grounded can help evaporate the water, however, this alone may not be enough. And in some instances, exercising engines to bring oil to operating temperature might not be possible at all due to aircraft location, proximity to other aircraft, etc. It is important to periodically test the oil for water (ppm) and monitor total acid number (TAN) and compare these to the levels set by the engine OEM.

If the lubricant is contaminated with water for an extended period eventually the TAN value will exceed OEM recommended limits, indicating it is time to change the lubricant. Some engine OEMs have fluid condition limits that stipulate a water level less than 1000ppm, and a TAN of less than 2.0. These are good general guidelines, but airlines need to consult their engine manuals for specific guidance. It’s also worth noting that there is no “too low” figure. For instance, MJO II right out of the can will typically have around 200-300ppm.

Much like exercising the engines, maintenance technicians may exercise the wheels in order to avoid flat spots by moving the airplane. Rolling tires also renews the grease coating on the associated wheel bearing components, which helps protect the bearings. This is important because wheel bearings are only re-greased when completely removed from the aircraft. Moving the airplane also flexes the landing gear which renews oil and grease films on landing gear struts and linkages.

Additionally, knowing that the usage of greases decreases during prolonged aircraft downtime, it’s important for airlines to properly store their greases and be mindful of shelf-life and contamination warning signs. Here are some tips on how to effectively accomplish this:

• Grease containers should be stored indoors in dry, cool and clean environments with temperatures ranges from 0°C to 40°C (32°F to 104°F). If a stored grease is briefly exposed to severe temperatures or environmental conditions, technicians should consult their lubricant suppliers with concerns.

• If a grease container is opened, the grease needs to be used as soon as possible to avoid potential contamination or degradation — which is an added concern when aircraft are grounded.

Improper storage may lead to hydrolysis, a risk factor for grease just as it is for turbine oils. Some signs grease has been compromised include unusual darker color, abnormal consistency and a strong, unpleasant odor. Oil separation may also be observed, however, greases with normal bleed can easily be mixed back together. If there’s excessive oil bleed, the grease will harden and be unsuitable for use.

While proper storage can help prevent these compromises, maintenance technicians also need to be mindful of shelf life and whether a container is open already. Shelf life specifications can differ between aviation greases. The average industry shelf life of aviation greases is about three years; however, ExxonMobil’s Mobilgrease 33 and Mobilgrease™ 28 aviation greases offer extended shelf life for up to 10 years.

While aviation grease shelf life is listed as the “use by” date on the container, the listed shelf life recommendation for a grease is no longer applicable once the container is opened. Once opened, greases with ester base oils are vulnerable to hydrolysis from absorbed water contamination and should be used as quickly as possible. ExxonMobil’s Mobilgrease 33 and Mobilgrease 28 aviation greases do not have these oils and using these can ease concerns around grease degradation. Also keeping a lid on the opened grease container helps prevent the ingress of particulate contamination.

While airlines work to keep grounded aircraft parked only temporarily, some aircraft are being put in long-term storage, or deep preservation. Long-term preservation is normally done when there is no timeline to return an engine to service. This may mean the engine will be out-of-service for six months or longer, and this is often a permanent situation.

When preserving or “pickling” an engine, preservation additives need to be added to the lubricants to prevent corrosion. Adding a preservative chemical should be done with the water level and TAN in compliance with OEM guidelines.

Once the long-term preservative additive is mixed in the lubricant, the engine operation is typically limited by the OEM as the preservative may interfere with other lubricant additives and create less load-carrying, or more deposits forming. Generally, once the preservative gets mixed and circulated, the engine sits without being operated until it is about to be put back into service, whenever that may be. Airlines know best when it is appropriate for them to use preservation fluid in engines as the workload to get a preserved engine back to airworthy status is a significant task.

In today’s environment, there are a lot of unknowns and this is especially true for the aviation industry. It could be that at some point a higher percentage of aircraft will be migrated from short-term storage to long-term preservation, and some will return to service. While much is unknown, airlines can maximize the effectiveness of their short-term storage effort by remaining mindful of lubricant-related risks, following OEM provided preservation requirements and taking the appropriate mitigation steps. These tips can also help ensure the airworthiness of an aircraft returned to service after extended downtime.

For anyone needing lubrication support during this time, ExxonMobil offers technical engineers to answer questions and provide support. You can contact ExxonMobil by visiting: https://www.exxonmobil.com/en/aviation/contact-us.

LOGIN or SUBSCRIBE

Enter you REGISTERED email

Aerospace Tech Review Magazine - Subscription Popup

Already a subscriber? Log in