Early 3% Failure Rate "Unacceptable"

An intriguing product designed to bring a here-to-fore unprecedented degree of realiability to GA vacuum pumps has apparently not held up in the field. After hearing very recent complaints from buyers of the Aero Advantage Dual Rotor Vacuum Pump, using the system on 540 series powerplants, we learned that the company has shut the doors and left a short message (see below) announcing their situation on the home page of their web site.

It was a novel product... Aero Advantage designed a Dual Rotor Vacuum Pump that incorporated a shear coupling between the forward rotor and the driveshaft. This allowed the forward rotor’s shear coupling to shear away from the driveshaft without causing the entire driveshaft to fail. A similar coupling was installed on the rear rotor. As an additional safeguard, the shaft had a 'necked down area' between the two rotors. This way, either the rear rotor’s shear coupling or the necked area in the driveshaft can shear away from the forward rotor without effecting the forward rotors continued operation.

In the event of a failure of either rotor, a monitoring system offered the pilot instant notification via a warning lamp in the cockpit, indicating which pumping chamber was inop.

The future of this product line looks dim. There are obviously some massive legal issues inherent in what has occurred, and the possible list of buyers for such a product would be limited by this... We'll keep you informed as soon as we have more information.

The Aero Advantage Customer Statement

Customer experience has uncovered a type of pump failure never experienced in years of field and laboratory testing of the dual rotor vacuum pump design, including the deliberate destruction of over 300 test pumps. These failures resulted in malfunctioning of both pumping chambers simultaneously. The failures are concentrated on the 300 horsepower Lycoming IO-540 engines. We believe that these engines generate a resonant frequency resulting in breakage of both graphite rotors. Multiple replacement pumps have failed on three different engines. At this point, we can’t be certain about similar failures occurring on other engines. A failure rate of 3%, while seemingly small, is not acceptable for our product. Although the dual rotor pumps are performing well in the other 97% of installations, shipping of dual rotor pumps has been halted. The tens of thousands of dollars of orders on hand will not be filled. Aero Advantage refuses to continue marketing a product that might not perform satisfactorily for all its customers.

Aero Advantage was founded, in good faith, to improve safety of flight and to allow greater peace of mind for its customers by eliminating sudden loss of the vacuum source. While the precise changes that are needed to improve reliability may already be in place, they would likely require between 3 and 9 months to finalize and place into production. The company can not survive the financial burden of having no sales for that length of time and is closing its doors. Closure of the business was an extremely difficult decision for me, the inventor and company founder, since I have invested five years of work and most of my life’s savings in the business.

Several parties have expressed an interest in procuring the current technology and continuing the development of the necessary product improvements.

It is with much regret that I announce the above decision. I believe it is the correct one for all concerned.

Sincerely, David A. Boldenow

FMI: www.aeroadvantage.com/index.htm