Beyond the Visible: How Pall Aerospace Powers the Future of Flight

Small Components, Critical Responsibility

Aerospace progress is often measured by faster aircraft, longer range, and new propulsion systems. Yet many advances depend on technologies that rarely attract attention. Filtration is one of them. By controlling contamination in fluids, air, and fuel, filtration helps protect critical systems, support reliability, and enable aircraft to operate in demanding environments. For nearly eight decades, Pall Corporation has contributed to this essential engineering discipline across commercial aviation, defense, rotorcraft, and space exploration.

The story began with Dr. David B. Pall, a chemist who developed a stainless-steel mesh filter to address the limitations of paper media used in early aircraft hydraulic systems. Responding to the need for more dependable protection on Boeing 707 aircraft, he created the sintered wire cloth Rigimesh filter. The technology offered a more effective way to safeguard hydraulic systems from contamination and established a foundation for continued aerospace innovation.

Pall soon challenged its own approach. During the 1960s, the company developed disposable glass fiber depth media, which became an aviation filtration standard. The work also reached beyond atmospheric flight. NASA engineers selected Pall technology for the Apollo program, including a porous metal heat exchanger used in Neil Armstrong’s spacesuit during the Apollo 11 mission. Pall also supplied Air filters that helped protect the lunar module atmosphere during cabin pressure equalization.

These applications demonstrate a recurring principle in aerospace engineering: components that may appear small can carry major responsibility. Effective contamination control protects more than equipment. It can support mission continuity, system performance, and the people who depend on both.

Protecting Rotorcraft in the Harshest Conditions

That principle became especially important in rotorcraft. In the early 1970s, Pall introduced a three micron, absolute rated filter for helicopter transmission systems. The technology enhanced lubricant system reliability and became a selected solution for the Chinook helicopter fleet. Pall also advanced engine air protection through its Centrisep Engine Air Protection Systems that later become known as Pall PUREair systems. These systems were developed to reduce the threat posed by particulate, sand and debris entering helicopter engines in some of the harshest operating conditions.

The challenge remains highly relevant. Rotorcraft often operate close to the ground, where dust and particulate concentrations can be severe. Missions may involve military operations, humanitarian support, rescue, or transport in remote locations. In each case, protecting the engine and transmission from contamination can help operators pursue availability, durability, and maintainability objectives. Pall filtration systems today support a broad range of helicopter fleets, reflecting decades of application experience across demanding environments.

Raising the Standard for Cabin Air

Commercial aviation introduced another challenge: cabin air quality. As air travel became more accessible during the 1980s, Pall engineers developed filtration technology for aircraft cabins. Within two years, the company’s filters became the first to qualify as HEPA rated cabin air filters, according to Pall’s historical materials. Continued microbial testing contributed to True HEPA filters by 1998, followed by Advanced Cabin Air Filters that combined HEPA and odor removal capabilities.

Pall also contributed to the development of industry practices, including the first European pre-standard on aircraft cabin air quality in 2004. The company later achieved certification for cockpit air filters designed to remove particulates and volatile organic compounds. During the COVID-19 pandemic, Pall’s PUREair cabin solutions and HEPA filtration capabilities underscored the importance of high efficiency particle removal in shared aircraft environments.

Preparing Filtration for New Energy Pathways

The next era of aviation will require filtration to address different fluids, contaminants, materials, and operating conditions. Sustainable aviation fuel is one example. Pall has participated in testing involving 100 percent sustainable aviation fuel on systems associated with Rolls-Royce Trent 700 and Trent XWB engines. This work reflects the need to evaluate established aircraft technologies as the industry considers lower carbon energy pathways.

Hydrogen powered flight creates another frontier. Pall Aerospace has been named as a key filtration provider in European Commission research projects linked to future Hydrogen powered flight and continue to push the envelope of what is possible for particulate and chemical filtration in the next generation of fuel cell propulsion systems.

The significance extends beyond a single project. Fuel cell propulsion introduces contamination control requirements that differ from conventional aircraft architectures. Particulates and chemical contaminants can threaten sensitive systems, making filtration an enabling consideration rather than a secondary component. By developing and validating solutions for this environment, Pall is applying nearly 80 years of aerospace experience to a new propulsion challenge.

Collaboration Turns Ambition into Flight-Ready Systems

This progression also shows why collaboration matters. Aerospace innovation rarely happens through one technology or organization. Aircraft manufacturers, propulsion specialists, research institutions, suppliers, and regulators must translate ambitious concepts into systems that can be tested and validated. Filtration partners contribute by understanding contamination risks, defining performance requirements, and engineering solutions that work within the physical and operational constraints of the aircraft.

That disciplined approach is valuable when emerging propulsion concepts move from laboratory development toward flight demonstration. Early attention to filtration can help teams identify contamination pathways, establish validation priorities, and integrate protective technologies before aircraft designs become difficult or costly to change.

An Innovation Legacy Built for What Comes Next

Across Pall’s history, the applications have changed, but the engineering objective has remained consistent: protect what matters so critical systems can perform as intended. The same mindset connects hydraulic filters on early jetliners, life support components used during Apollo 11, cabin air filtration, helicopter engine protection, sustainable aviation fuel testing, and filtration for hydrogen fuel cell propulsion.

For the aerospace sector, that continuity is instructive. New propulsion technologies will bring new design questions, but reliability will still depend on disciplined attention to every system interface. Contamination control will remain fundamental wherever air, fuel, lubricant, hydraulic fluid, or process gases must meet exacting requirements.

Pall’s aerospace legacy therefore is not simply a record of past milestones. It is a platform for the next generation of flight. As aviation pursues greater efficiency, new energy sources, and more sustainable operations, filtration will continue to work behind the scenes, protecting systems and enabling progress. The technology may remain largely unseen, but its contribution to aerospace performance, safety, and innovation is built into the journey.

Editorial source note: Prepared from the supplied Pall aerospace history document, video script, and approved ZEROe Q&A language. Financial details are excluded.