A Donaldson inlet barrier filter (IBF) for the Robinson R66 Turbine has been certified by the Federal Aviation Administration as an addition to the R66’s type certificate, and Donaldson is to begin taking orders for the product at HAI Heli-Expo 2017 in Dallas, Texas.
The IBF, which will be on display at Heli-Expo next week, is available as an option in new aircraft or as a kit for retrofit, and replaces an existing Robinson filter.
With an installed weight of less than seven pounds, the performance of the oil-wetted Donaldson IBF is said to be comparable to the Robinson filter with respect to pressure drop, while providing an enhanced separation efficiency of more than 99 percent.
“Low pressure drop improves the efficiency of the engine — so you get better fuel efficiency as well as getting the turbine to run cooler, so you get better altitude performance,” said Peter Riedl, VP of engineering at Robinson Helicopter. “The efficiency in getting the dust out of the air, that’s the other part [to extend the life of the engine] — and I think that the Donaldson filter does a very good job of both.”
The two companies worked closely together to develop and certify the product, with work beginning in earnest at Donaldson about two years ago.
“We had it on our radar screen as an STC project initially,” said Tom Newman, engineering director at Donaldson, “but in talking and dealing with Robinson, they had a customer request [for it and] I think that drove our relationship to get this going.”
The potential market for the filter is enormous, with over 800 R66s now in operation around the world.
Riedl said operators in Australia, in particular, had been calling for the IBF. Newman said he expected wider adoption after the first wave of users found the benefits of the product.
“We’ve seen adaptation of the Donaldson IBF systems initially with customers flying in austere environments, and have the potential to ingest a lot of fine particulate contaminates that cause engine erosion and glazing in the hot sections,” said Newman, “but after we get those early adopters satisfied, we do tend to see a lot of broader adaptation — just because the aircraft owners/operators realize the efficiency inlet protection provides to their bottom line in terms of maintenance and overall on the engine.”
Newman added that Donaldson has also been doing a lot of work in substantiating the effectiveness of its IBFs in removing airborne salt — a major benefit for those operating in a maritime environment.
“The filters are very efficient at doing that as well — we’re in excess of 94 percent removing laden salt from the airborne environment, and obviously keeping salt out of the engine prolongs engine life and reduces overhaul cost,” he said.
The install time for retrofit is less than eight man-hours, according to Riedl, although he said he hoped to reduce that time in future. To begin with, the filter will be available through Robinson and any Robinson Service Center, but plans are in place for Donaldson to eventually offer the retrofit directly to customers, too.
