USDA - VGs Provide Aerodynamic Boost for Agriculture!

Anni Brogan, owner and president of Micro Aerodynamics, inspecting vortex generators (VGs) on the wings of a small aircraft

Anni Brogan, owner and president of Micro Aerodynamics, inspects vortex generators ( VGs ) on the wings of a small aircraft used in studies by ARS engineer Dan Martin.

Agriculture Gets an Aerodynamic Boost!

ARS engineer Dan Martin found that the dime-sized metal clips can help ensure more accurate targeting of pesticides.  Brogan’s firm Micro AeroDynamics Inc. provided MicroAero VGs used in the research.

Hitting your target—and only your target—is a top priority when spraying pesticides from an airplane. And the use of a small object could be a big help in making sure that happens.

That’s the focus of the research being conducted by Daniel Martin, an engineer with Agricultural Research Service’s (ARS) Aerial Application Technology Research Unit in College Station, Texas. Martin has shown that attaching dime-sized metal clips to airplane wings—a technology known as “vortex generators”—can reduce pesticide drift.

Vortex generators (VGs) are common on commercial airliners as well as on smaller aircraft to provide pilots better control of the aircraft. Now, thanks to Martin and others, VGs are reducing the drift of pesticides sprayed by agricultural aircraft.

“It’s a matter of aerodynamics,” Martin says. An airplane gets lift from an area of high pressure passing under the wings and an area of low pressure passing over them. But as air passes over and under the wings, it moves up and around them in chaotic whirlwind patterns, particularly at the wing tips. VGs are T-shaped, and when they are attached to the edge of the wing, each one becomes a focal point (a vortex) that stabilizes the flow of air as it passes over and under the wing.

On most agricultural aircraft, the spray nozzles are attached to booms that hang below the wings. VGs make for a smoother and more controlled flow of air below the wing near those nozzles. “VGs channel the air flow and concentrate it so that it pushes the spray down towards the crop canopy,” Martin says. VGs also are often attached to the plane’s rear stabilizer to produce the same beneficial effect. The overall effect is less pesticide drifting off target.

Martin started evaluating VGs a few years ago in an effort to reduce spray drift. He and his colleagues sprayed a target field near College Station to measure drift and deposition rates of a test spray released from a plane. They placed moisture-sensitive cards at various distances outside the target to measure downwind deposits.

The results showed that the type of clips used in the study, Micro VGs, produced by Micro Aerodynamics, Inc. of Anacortes, Washington, dramatically reduced downwind deposits and drift.

Posted by Dennis O'Brien, Public Affairs Specialist, Agricultural Research Service, on December 6, 2016 at 10:00 AM

CAPE AIR - Installs Micro Vortex Generator Kits on Cessna 402C Fleet

Cape Air's Cessna 402C with Micro VGs

Cape Air's Cessna 402C with Micro VGsMicro VG Kit

Micro's VG Kit for the Cessna 402C provides virtual elimination of Vmc, a dramatic improvement in characteristics, reduced stall speeds, reduced accelerate/stop distance, and improved safety. You also get a 360 pound Gross Weight Increase.

Our kit consists of 118 vortex generators mounted on the wings, just aft of the boot line and on both sides of the vertical stabilizer, plus four strakes on the inside and outside of the engine nacelles. The Micro VG Kit includes an FAA approved Pilot's Operating Handbook Supplement (POHS).

See Micro VG Kit Catalog Sheet for the Cessna 402C

How Micro VGs Work

Micro Vortex Generators are placed in a spanwise line two to fifteen percent aft of the leading edge of the wing. They control airflow over the upper surface of the wing and the tail surfaces by creating vortices that energize the boundary layer. This results in improved performance and control authority at low airspeeds up to the critical angle of attack.

What-VGs-do

A Micro Vortex Generator creates a tiny vortex in the airstream over an airfoil. This vortex energizes the normally stagnant boundary layer of air on the wing and tail surfaces. An energized boundary layer is more resistant to flow separation than a stagnant boundary layer. The result is that airflow "sticks" to the wing and control surfaces better, providing greater lift, which results in greater control in flight at slower airspeeds such as take-off and landing.