Award Winning Innovations

:: Vortex Control Devices

:: VC Eaglets Testimonials

"The Consulting Aviation Services Vortex Control Eaglets invention is a major breakthrough, significantly improving the stall handling of light twin engine aircraft."

Sean C. Roberts
Director of the National Test Pilot School in California.


"The Eaglets will have a significant impact on the prevention of stall spin accidents."

John Ralston
President of Bihrle Applied Research, Inc., a Hampton, VA firm which assesses aircraft stall and spin situations.

Vortex Control Eaglets
Vortex Control Finlets

VC Eaglet - Delays wing stall on all types of aircraft

The Vortex Control Eaglet ™ (VC Eaglet) is under patent to CAS. VC Eaglets were awarded the Ben T. Epps Aerospace Innovation Achievement Award for Best Invention. Used on the leading edge of airfoil surfaces, the VC Eaglet helps maintain post stall flow over the aileron and other control surfaces. If the airplane is too close to stall, a gust can put it into post-stall conditions. On many airplanes this causes complete loss of roll damping, and some aircraft have aileron reversal. The VC Eaglet is a simple airplane modification that can prevent this hazardous situation and significantly improve aircraft safety. In order to prove the concept CAS recently conducted flight tests in collaboration with The National Test Pilot School in Mojave, California.

VC Eaglet installed on a Derringer Airplane

VC Eaglet installed on a Derringer Airplane

The National Test Pilot School provided a Derringer Airplane to conduct the flight test. The flight test demonstrated the following results:

  • The dynamic response of vortex lift was demonstrated by immediate roll damping.
  • VC Eaglets enabled the stall recovery to be delayed seven (7) degrees angle of attack for the clean airplane at idle power.
  • VC Eaglets enabled the stall recovery to be delayed five (5) degrees angle of attack for the configuration with full flaps, gear down and at maximum continuous power.

The flight test also validated CASSC 2.6 ©, software developed by Consulting Aviation Services Inc. as shown by the following:

  • Flow separation indicated with tufts showed the same span wise progression as predicted by CASSC.
  • Based on the recorded data, the angle of attack for initiation of stall and that for fully developed stall agreed with CASSC.
  • Elimination of aileron reversal by the Eaglets was demonstrated. As predicted by CASSC, aileron effectiveness was very low in the fully stalled condition, but no aileron reversal occurred even with full aileron deflection.
  • The improved roll damping predicted by CASSC was illustrated by the video results, and the pilotís comments substantiate this.

The VC Eaglet configuration can be uniquely tailored for all aircraft with the CASSC 2.6 software, providing little or no added drag during normal cruise or climb out attitudes. See the VC Eaglet Brochure for more information.

Launch in external player VC Eaglets Flight Test

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VC Finlet - Reduces drag on upward swept fuselage aircraft

The Vortex Control Finlet ™, (VC Finlets) concept is based on the principle of moving high-energy airflow from the side of the fuselage to the after body by creating coherent vortices to entrain the flow to the lower after body surface. This principle is well proven by the NACA flush inlet concept. As with the flush inlet, VC Finlets are expected to raise the lower after body surface pressure to very near the ambient pressure.

The Vortex Control Finlet (VC Finlet) significantly reduces separated flow and induced drag for aircraft with upswept aft fuselages such as the C-130 and many other existing airplanes. With the reduction in drag comes reduced fuel consumption and increased range. CAS can analyze each aircraft and individually adapt the VC Finlet configuration for maximum performance for each customer.

Consulting Aviation Services, Inc. (CAS) is currently under Air Force contract to develop Vortex Control Finlets for the C-130 aircraft. CAS will continue the effort through wind tunnel testing. CAS will then join with Advanced Aviation Products, LLC (AAP) to continue the development through flight test, marketing and manufacturing.

CAS owns a US patent for VC Finlets. Post-stall and Vortex flow analysis are accomplished with CASSC 2.6, a unique software developed and copyrighted by CAS.

For additional information download the VC Finlet Brochure or visit Advanced Aviation Products.

Flow Conditions on C-130 without VC Finlets Flow Conditions on C-130 without VC Finlets
VC Finlets can reduce C-130 drag by 13%
Flow Conditions with Vortex Control Finlet Installed
Flow Conditions with VC Finlet Installed

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