Applies Boundary Layer Phenomena to Improve Flight in Planes and Helicopters
By Karen Sanders
Most people look at airplanes and helicopters and ask, “How do they fly?” BLR Aerospace looks at aircraft and asks, “How do we make them fly better?”
Formerly Boundary Layer Research, BLR Aerospace is an aerospace research and development firm. According its website, the company specializes in “the engineering, certifying, manufacturing, and marketing of after-market aerodynamic components and systems that can enhance the productivity, performance, and safety of general, commercial, and military aircraft. “
BLR started in 1992 in Everett Washington with four employees, including company president and founder, Robert Desroche. A Navy veteran, Desroche later became a pilot, leading him to found the company. In 15 years, the company has grown to 50 employees, including contractors and associates and 60 STC (Supplemental Type Certificate) approvals to improve flight safety and handling by the FAA (Federal Aviation Administration) for after-market aircraft modifications.
The company’s primary product lines involve airflow manipulation technologies that focus on the boundary layer, the very thin layer of air flowing over the surface of an aircraft wing, or airfoil. The molecules that directly touch the wing’s surface are virtually motionless while each layer of molecules within the boundary layer moves faster than the layers closer to the wing’s surface. The flow outside the boundary layer reacts to the shape of the edge of the boundary layer just like it would to the physical surface of an object. By altering the shape of the boundary layer, you can change the stability, lift, drag, and heat friction of the wing.
BLR’s first product was a vortex generator, a small aluminum device about half an inch tall and two inches long, thin like a blade, and normally installed in pairs that entice the air to flow around the curvature of the wing, enhancing lift. This product and many others resulted from a gift of Robert Desroche’s, according to Dave Marone, BLR vice president of sales and marketing. “Bob’s distinctive talent is his ability to walk around an aircraft and identify opportunities to improve its performance. It’s exciting to examine an aircraft with him and see it through his eyes.”
Started with Airplanes
BLR first started with fixed-wing aircraft, developing products that include vortex generators, winglets, wingtip fuel tanks, aft body strakes, and landing gear upgrades. Depending on the product, these components can give increased safety margins, greater payload capacity, better fuel economy, longer range, and slower approach speeds.
In the civilian world, BLR makes products for the Beechcraft Baron, Duke, King Air, and Travel-Air; many Cessna models from the 172 to the 441; the DeHavilland DHC-2 MKI Beaver; and the Piper, including the Aerostar, Mojave, Navajo, Panthers I and II, and Senecas II, III, and IV models. For military aircraft, BLR is developing products for models of the Hercules, Hawkeye, and Army C-12.
Many of these products are so widely accepted that some think BLR innovations are factory standard and not after-market modifications. One aircraft where BLR winglet and performance enhancing systems are common is the Beechcraft Duke, as BLR innovations fly on over 50 percent of the fleet.
BLR started working with helicopters, or rotary-wing aircraft, in 1998, after Desroche read a paper on tail boom strakes technology by NASA’s Langley Research Center. The center worked on this technology after being asked by the U.S. Army to study a problem they were having with their helicopters called loss of tail rotor effectiveness, or LTE. Using research involving techniques such as wind tunnels, tufting, and computational fluid dynamics, NASA found that the main rotor wash was being accelerated as it went around the curved tail boom. This acceleration of airflow and resultant increased pressure acted against the boom, causing a force movement disadvantageous to controlling the helicopter. This information was never commercially applied to helicopters until BLR began working with NASA. They acquired an exclusive NASA technology-transfer license to research products resulting from this data.
Currently, they make dual tail boom strakes to change the airflow around the helicopter, combating LTE and increasing stability and payload. Some 600 BLR strake-equipped helicopters have over a million flight hours by 128 operators. BLR has certified products such as the dual tail boom strakes and FastFin, available for both the military and civilian Bell helicopters and for military models including the 206 Jet Ranger, 206 Long Ranger, 205B (Huey II), 212, 412, UH-1H, and UH-1F. Currently, they are developing products for the Agusta, Eurocopter, Sikorsky, and Boeing military helicopters.
Although BLR has STCs for the physical installation of the strakes and FastFin, they are now looking to certify a change in the weight limits of the Bell 212 at higher altitudes. They are gathering the data necessary for this change by doing flight tests, quantifying their performance claims.
BLR helicopter products also work to help pilots maintain control of helicopters, which are inherently unstable. Overcoming that instability and maintaining control is the key to successful flight. Marone uses a game to explain the issue of control. “Flying a helicopter is a lot like playing the game Labyrinth, where you try to direct the path of a ball through a maze. Like the game, the key to being effective in flying a helicopter is keeping it under control. Once it gets out of control it, can go from being slightly out of control to unrecoverable very quickly.”
Testing, Testing, and More Testing
BLR has produced over 60 FAA STC approvals for after-market aircraft modifications for fixed- and rotary-wing aircraft. Because these approvals involve the aircrafts’ primary structure, they are very in-depth and time consuming. A team including engineers, technicians, and pilots does extensive design and testing before a product can be approved and manufactured. Testing can include structural analysis, static destruction, wind tunnels, tufting, icing, and flutter tests.
BLR’s location on Paine Field in Everett is an essential component of their success. Both Boeing and the University of Washington have testing resources BLR uses. Also, the Puget Sound area is a hub of aerospace companies, providing workers skilled in aerospace technologies.
Aluminum and carbon fiber see use in many of BLR’s product designs. Design teams consist of staff and contract engineers, usually having degrees in mechanical engineering, often specializing in structures or materials. Mike Carpenter, BLR’s chief engineer and general manager, is a civil engineer specializing in structural engineering and came to BLR as a contractor after working for several years in other aerospace companies.
BLR is involved in exporting, with about 20 percent of its sales overseas. The company got into the export business simply because so many American-built aircraft have foreign owners interested in BLR products to improve performance and safety and extend aircraft life. It is cheaper to upgrade existing aircraft than spend millions of dollars to buy new ones. This has led to BLR selling to customers in over 110 countries.
As a testament to its success, in its 15-year history in aerospace, BLR has grown from 1 to 60 STC approvals, branched out from fixed-wing to rotary-wing, and become proficient at exporting. This growth has led to consideration of adding corporate offices off the airport at Paine Field, to provide a more comfortable setting in which to meet customers.
BLR Aerospace (formerly Boundary Layer Research)
Aerospace research and development company specializing in after market modifications for fixed- and rotary-wing aircraft to improve performance and safety.
Types of engineers they use:
An occasional electrical engineer, but mostly mechanical and some civil engineers, especially those with experience in structures, fatigue, and testing. They also use Designated Engineering Representatives (DER) certified by the FAA.
Outlook for hiring engineers:
Currently they are hiring one engineer and a few contractors or outsourced jobs.
What they look for in engineers:
The most important thing is experience with aerospace, airplanes, and helicopters, including design, structures, and fatigue.
Contact for submitting resumes:
E-mail to hr@BLRaerospace.com
Old dams are being taken down around the country for environmental and safety reasons. In Massachusetts, the story of the Upper Roberts Meadow Reservoir Dam removal project shows the complexities involved and the opportunities for engineers.
Mechanical engineers help with knee injuries by developing computational models to characterize ligaments.
Vertical farming offers opportunities to grow more crops on a smaller footprint, especially in urban areas. It also presents unique educational opportunities.
Develops soft exoskeletons that improve walking for soldiers and others.
In the state of Hawaii, rooftop solar panels are popping up everywhere. On the island of Oahu, where most of the state’s population lives, roughly 12 percent of utility customers have rooftop solar, compared to an average of 0.5 percent in the mainland United States.