military helicopters

Fiberglass vs. All-Metal Filters – What the Research Shows

New research presented recently to the American Filtration and Separations Society (AFS) provided some exciting new insight into just how effective metal filter media are compared to standard fiberglass filters when it comes to aircraft hydraulic filtration.

Woven metal mesh and a variety of sintered metal filter media have all been “real-life tested” in commercial and military aviation applications in recent years to see how each compared to traditional glass fiber, aka fiberglass filters.

Bottom Line: All-Metal Filters Outperform Fiberglass in Aviation Applications

The results from this testing have been impressive, and also extremely gratifying for metal filter manufacturers and suppliers like us here at Fluid Conditioning Products (FCP).

While we also produce a limited selection of disposable filter elements for various applications utilizing legacy materials such as cellulose, paper, spun polyester, and fiberglass, these are not our primary focus. We are especially proud to be known for our all-metal, corrosion-resistant wire mesh filters made from stainless steel, nickel-copper, brass, and bronze.

In both US Army testing in Blackhawk and other helicopters, and commercial airline testing in Boeing 737 jets, all-metal filters have been proven to reduce contamination in hydraulic systems and cut maintenance on a variety of other components.

It’s becoming clear that all-metal filters should be considered the standard in the aerospace and defense industries going forward. Today’s blog post highlights three big outcomes from testing of all-metal filters that prove this assertion.

Testing in Army Helicopters Shows Excellent Results

In recent years, a variety of all-metal filter manufacturers and suppliers submitted products for real-world (as opposed to traditional laboratory) testing to the US Army Aviation Engineering Directorate (AED). The AED had put a testing programme in place to determine ways to improve the cleanliness of the hydraulic systems in several helicopter models.

Our friends at Baekert published a white paper to share some of the test case results with a metal fiber filter media that they submitted, and the results are excellent.

1.      Metal Fiber Filters Dramatically Reduce Maintenance vs. Glass Fiber

A remarkable reduction of maintenance by 10 times on six components in a 36,000-hour test on 120 helicopters was reported by the AED with the use of metal fiber filters vs. fiberglass.

This data came from comparing the number of equipment failures in the hydraulic pump, primary servo, SAS actuators (for pitch trim, roll, and yaw boost), and the tail rotor servo. All of the failure rates dropped by between 88%-92% with all-metal filters!

2.      Metal Fiber Filters Produce Enormous Cost Savings Opportunities

As you can imagine, the cost savings associated with the massive reduction in maintenance time that metal fiber filters achieved in testing were substantial. As reported by the US AED, all-metal filters can save about $4 million per every 100 hours of flight time in a fleet of 2,000 helicopters. Most of that savings is generated in having to replace so many fewer hydraulic pumps and primary servo components.

Testing in Commercial Aircrafts is Also Promising for All-Metal Filters

While not reported in Baekert’s white paper, all-metal filters are also being tested as replacements for fiberglass filter media in commercial aircraft, including the popular Boeing 737 used by Southwest Airlines.

3.      All-Metal Filters Dramatically Reduce Contamination in Hydraulic Systems

Because all-metal filters do not shed particles that release matter back into the hydraulic system fluid, they can reduce contamination, thereby cutting maintenance costs and time by leaps and bounds. Early testing in commercial aircraft has shown contamination reduction with all-metal filters of about 95%!

All-Metal Filters Present Opportunities That Are More Important Now Than Ever

While the future outlook for the aerospace and defense industries was strong within the last year or so, unfortunately, our world has drastically changed in 2020.

Commercial aircraft manufacturers especially are now looking for cost savings anywhere they can. Luckily, all-metal filters present some fantastic opportunities that we covered here today, specifically related to the maintenance of aircraft hydraulic systems.

airplane diagram

Commercial aircraft have many other filtration components that can also potentially be shifted to all-metal filter designs in the future, as our illustration indicates. Benefits over fiberglass filters in these uses include superior cleanliness with no particle shedding, the ability to dissipate static charges, and overall compact filter design.

Have a Sintered Metal Filter or Other All-Metal Filter Project on the Horizon?

Fluid Conditioning Products is here to provide precision-engineered filtration products for the technically demanding aerospace industry and more.

Contact us today with your filtration questions or project specifications and experience the FCP difference.