The COVID-19 pandemic affected all aspects of the paint and coatings. The aerospace coatings industry was especially hard hit as the pandemic brought airline travel to a virtual standstill. As we (hopefully) reach the end of the pandemic entering 2022, airline travel has begun to pick up. Aerospace coatings manufacturers Coatings World interviewed said that they have had to adapt to the changing market conditions and do no expect full recovery for another two to three years.

“The COVID-19 pandemic is still affecting PPG’s global businesses in many ways, some of which will extend beyond the current crisis,” said Sam Millikin, PPG global director, coatings and sealants, aerospace. “In addition to reductions in the commercial aviation segment, customer operational changes have resulted in more frequent orders with lower product volume per order. We continue to adapt to changing market dynamics by partnering with our customers and providing value added coatings products and solutions.”

According to Millikin, full recovery of the global airline industry is not expected for another two to three years.   “Domestic air travel in most parts of the world started to recover midway through 2021 and is expected to reach 2019 levels by early 2023. International air travel is predicted to lag by one to two years. The aerospace coatings segment should see a full recovery in 2023, as global air travel begins to return to normal.”

In the first quarter of 2022, Sherwin-Williams Aerospace commissioned an extensive survey of the pandemic’s effect on the North American MRO marketplace. From the input of more than 200 North American MRO decision-makers, the survey concluded that from the COVID-19 impact:
• 45% experienced little or no effect on operations
• 33% experienced a negative effect
• 11% experienced a dramatic negative effect
• 10% experienced positive results during the pandemic.

“The aerospace coatings segment includes more than the airline industry,” said Julie Voisin, global marketing manager, Sherwin-Williams Aerospace Coatings. “It also includes the general aviation/business jet market segment as well as military aircraft. These segments are running strong right now, and have not had the same impacts as the commercial
airline industry.”

The same survey Sherwin-Williams commissioned in Q1 2022 on COVID-19’s lasting effects asked North American-based MRO facility owners/operators and managers when they felt the aerospace market would return to prepandemic levels:
• 22% indicated it would be this year (2022)
• 45% indicated it would by end next year (in 2023)
• 45% indicated it would be back after 2024 or later

“This is a complex question,” Voisin noted. “Recovery requires several levels. Aircraft need to fly more, requiring more maintenance, which increases the aerospace
coatings demand.”  

“The aviation industry was one of the hardest hit by the COVID crisis,” said René Lang, executive managing director – head of aviation at Mankiewicz. “In the first half of the pandemic, OEMs significantly reduced their production rates and airlines also cut back their investments and only carried out necessary maintenance. This also resulted in significantly less painting. For some time now, the industry has almost returned to a standard level and so have the paint manufacturers in this sector.”

In addition, Lang noted many airlines were worried that the long grounding times, some of them in the desert, might have an impact on the exterior paint system. “Mankiewicz was able to reassure its customers in this regard: The ALEXIT BaseCoat/ClearCoat paint system for aircraft exteriors from Mankiewicz is designed to withstand particularly high UV exposure. This cannot affect the coating system at all, whether in the air or on the ground. Gloss and color remain intact for more than a decade. UV exposure at flight altitude is much higher anyway. Any heavy staining can also be removed very easily. And if in doubt, the protective clearcoat layer can also be polished.”

The International Air Transport Association (IATA) predicts the industry will be at pre-COVID levels in three years. Many measures were taken to give passengers back safety and confidence in flying. Coatings also play a major role here, especially in the interior. Hygiene is now equally as important to passengers as comfort and privacy on board. The hygiene and well-being onboard include many factors that make up a holistic system. Mankiewicz sees this as a building. The foundation can be the so-called “Care free coating” concept from Mankiewicz. ALEXIT FST PUReGuard meets all the strict requirements for cabin interior coatings and has also been equipped with antimicrobial active additives.

This long-term solution does not have to be constantly reapplied, and independent institutes attest to the paint system’s effectiveness over many years. In addition, all manufacturers are working on touchless solutions, and a lot of disinfecting and cleaning is done for short-term hygiene. The fact that surfaces in aircraft cabins painted with Mankiewicz cabin interior paints can withstand this increased chemical load is the roof of the building. By testing several AMS 1452/1453 certified disinfectants in an extensive test program Mankiewicz proves that their own paint product range is highly resistant against those chemicals. Even over a long time period the technical or visual quality is not affected and therefore, the lifetime of sensitive plastics can even be significantly extended by the durability and longevity of Mankiewicz cabin interior coatings.

Paint filling machines play a crucial role in the aerospace industry by ensuring precise and efficient filling of coatings used for aircraft painting. These machines help maintain consistency in the application of specialized aerospace coatings, which are essential for protecting aircraft surfaces from environmental damage and enhancing performance. 

In addition to products that contribute to holistic hygiene, everything related to the topic of sustainability plays a decisive role. All airlines and manufacturers are striving in this direction. “It is critically important for us as a coatings manufacturer to make a high contribution – yesterday, today and in the future,” said Lang. “We naturally take care in product development to prevent harmful substances, to further develop water-based products with the lowest possible VOC, and thus to promote our own sustainability. In addition, we help our customers to save entire process steps, materials, layers, or drying. The topic of weight is the most crucial for our airline customers because there is a direct correlation to the biggest CO2 polluter: fuel consumption. Mankiewicz has solutions ready in all three relevant areas of aviation coatings.”

In the exterior area, entire layers are saved with the ALEXIT BaseCoat/ClearCoat system, which next to weight savings enables better airflow through extremely smooth surfaces. In the interior, metals that are too heavy can be substituted by lightweight substrates with metallic effect paints that also meet “FST” (Fire, Smoke, Toxicity) requirements and visually give a very high-quality impression and a “home away from home” feeling in the air.

Customer Demand

Reducing coatings weight on painted aircraft has long been on the aerospace industry’s radar and it remains a top priority. Lowering the weight of an aircraft improves fuel efficiency that can result in significant operating cost savings and reduced greenhouse gas emissions when translated across a fleet. “One specific weight reducing product is PPG AEROCRON chrome-free, electrocoat (e-coat) primer, which is used to coat structural parts by electrodeposition instead of a traditional spray process and provides a more uniform film thickness on the part,” said Millikin. “This can result in up to 75 percent weight savings on highly complex parts.”

When working through innovative solutions and technologies for aircraft coatings, reducing weight is just one of the many considerations that go into PPG’s aerospace coatings products. “Superior appearance, ease and speed of application, durability and product quality are all of value to our customers,” Millikin said. “Aircraft painters, maintenance operations and airframe manufacturers have also quickly adopted basecoat-clearcoat. Our PPG DESOTHANE HD basecoat-clearcoat product line provides additional value to our customers by providing outstanding appearance, excellent service life and faster processing time. Potential weight savings is possible, but it depends on application and complexity of the aircraft livery.”

Sherwin-Williams Aerospace customers, be they MROs, OEMs, or GA owners and operators, want productivity, durability and appearance quality, according to Voisin. “The latest exterior coatings, like Sherwin-Williams SKYscapes basecoat-clearcoat paint systems, potentially save time and money, the latter because of much faster dry times – meaning the aircraft returns to service much faster. It also provides the superior appearance and durability regional and larger commercial airlines want … and their passengers expect.”

Basecoat-clearcoat systems cure at ambient temperature in half the time of single-stage aerospace paint systems. “The SKYscapes system is dry to tape in about two hours,” she said. “That means the MRO crew is already working on another part of the plane or adding another decorative color. In all, this provides the best of both worlds; the paint shops can add to their bottom line with faster production turnaround, a reduced carbon footprint by using less energy, and their customers get their plane back on time, and maybe even ahead of schedule.”

“Sherwin-Williams works diligently to provide customized product and process solutions to OEMs and MROs so that they can excel at productivity and provide their customers with the industry’s best durability and appearance. Customers are now also looking for products and processes that are focused on sustainability.”

Lang noted that in addition to weight, speed in the supply chain is significantly important.

“New and sustainable manufacturing methods such as additive manufacturing are desired,” said Lang. “3D printing of spare parts plays a major role in today’s highly internationalized supply chain. And as with any new technology new challenges need to be overcome: The additive manufacturing technique typically produces furrows, which particularly poses a problem for their subsequent coating – for the paint to achieve a shiny and smooth surface anyway it is necessary to first compensate those furrows with fillers. And ideally, these fillers are very easy and safe to apply.”

Lang said it is not as easy as it might sound. “As the furrows made by a 3D printer are deeper than the unevenness normally found on aircraft components, a larger amount of filler material is needed. When applied in thicker layers, many types of fillers no longer pass the fire safety requirements such as the heat release rate and so are unsuitable for the aviation industry.”

“Mankiewicz is well known for its custom-designed solutions and so responded to this challenge with a perfectly fitting product: a new generation of filler was specially developed and OEM qualified for use on 3D-printed components and conforms to the fire safety requirements including the heat release rate test even in cases of deep furrows – and consequently a thicker layer of the product – without any problem. The filler is specially adapted to the demands of the aviation industry – and enables unhindered exploitation of 3D-printed components with good filling properties and no shrinkage.”

The repaint cycle of an airplane is dependent on a variety of factors, including the airline, region, weather conditions and original coatings technology applied. “We are seeing the repaint cycle increasing and going beyond the traditional five to six years, but this is not becoming the new standard yet,” said Millikin.

Both PPG Desothane HD basecoat-clearcoat and PPG Aerocron electrocoat primer provide potential opportunities to increase productivity. PPG Desothane HD basecoat-clearcoat technology offers higher chemical resistance and higher erosion protection that can extend the life of a paint job. Airlines can operate their aircraft longer with fewer repaint cycles. PPG Aerocron primer, where metal parts are dipped into an electrically charged tank containing primer, offers significant process time savings. Thermal curing occurs in about 30 minutes, while spray primers typically require seven days to fully cure. As a result, parts can be coated and put back onto the aircraft quicker, so aircraft are back in service sooner.

“A well-prepped, professionally applied aircraft refinish (using a quality paint system) should last in the neighborhood for a commercial or regional airliner seven to 10 years,” said Voisin. “Business jets may choose to refinish their aircraft in the five-to-eight-year range. This period may be shorter or longer dependent upon the aircraft’s level of workload and environmental exposure.”

According to Voisin, aircraft are being repainted and/or the livery changed for a variety of reasons – the plane may be sold, leased to someone new, reached its required maintenance checks, or the owner just wants something different. “In the regional and commercial airliner world – the plane is an extension of the brand, and the look of the livery reflects the confidence passengers should have in the plane and the people flying and servicing it. That means you want an aircraft that reflects quality, safety, and professionalism.”

Typically, an aircraft flies around seven years with modern paint systems. “We monitored several aircraft that have been painted with our ALEXIT BaseCoat/ClearCoat paint system that have now been flying for more than ten years and some for even more than 13 years and still have a good gloss and their exterior skin is fairly intact. This is twice as long as required and usual,” said Lang. “This is a major achievement, as it saves the airline considerable amounts of money.”

In addition to the standard repaints after a certain period, livery changes/rebrandings, lease endings and sales often require paint jobs out of sequence. “We are very proud of the implemented rebrandings or even airline start-ups and the corresponding livery consulting,” Lang said. “Here, our in-house designers and colorimetric experts work hand-in-hand with the customer to develop great ideas, which are then reliably brought to life with the support of our technicians.”

Specialty liveries – when an aircraft becomes a work of art or advertising media – are also a growth opportunity for aerospace coatings. “One of these particularly beautiful examples is the painting of an aircraft in the colors of a luxury car,” said Lang. “The aircraft’s owner wanted the planes painting to match his car. The colorimetry specialists at Mankiewicz Coating Solutions accepted the challenge and recreated the exact color tones of the luxury car. The result is a sparkling variety of noble blue and brown tones in addition to rose gold that have been applied within in a seamless color gradient with intensely glittering micas. And of course, all implemented in a high-performance aircraft coating system that can withstand the harsh conditions of flight operations for many years.”