Gene Cernan: Apollo XVII Commander
First, your design, development and installation of the strakes were extremely professional. The quality of your work is uncontestable and something I sincerely appreciate. Although the precise airspeed advantage gained with the strakes depends upon the weight, power setting, temperature, etc as well as pilot technique, I can confidently say my 421 gives me an additional 6-9 knots under most conditions. The rate of climb advantage gained is around 100-200'/minute. Noticeable is the flat (lower angle of attack) attitude the aircraft assumes immediately after liftoff. Landings appear normal but I'd like to believe the rollout is a bit shorter. I haven't really checked out the extremely low speed characteristics yet, but I would hope that the strakes would provide somewhat more yaw stability in the event of a loss of engine on takeoff. Last but not least, they look awesome the 421 and now we can fly with the 'big boys!'
Jerry Kroese: Conquest Pilot
As the pilot for a small corporation flying the Cessna 425 Conquest, I am pleased to offer a positive testimonial to Mr. Steve Hinckley and Aircraft Performance Modifications, Inc. In March 2008 after installing the Dual Strakes supplied by Aircraft Performance Modifications, Inc. I noticed a definite 8 - 10 knot increase in indicated airspeed upon my return flight from maintenance in Wichita, KS to our home base in Nebraska. The positive increase in performance has played out in subsequent flights. With the extremely high cost of jet fuel this will amount to significant savings over time. Thank you for offering an after-market mod that works as advertised!
Barry Farrah: Conquest II Pilot
Most notable has been the improvement in the stability of the aircraft from the perspective of passengers. I have passengers who regularly were in the aircraft before the strakes were installed. Upon their first flight after the strakes were installed they conveyed to me that it felt more stable. This was primarily noticed on short final. They do not know how to say this, but basically they are noticing a more stable aircraft after I disconnect the yaw damper on short final.
Second, I have observed a modest increase in cruise speed. the folks at Weststar [Grand Junction, CO] calculated the increase to be be 4.5 knots. My engines are nearly due for overhaul. As a result, before the strakes were installed the aircraft was performing at 7 knots below book. It now performs at 2.5 knots below book. I don't know if the improvement will be more pronounced after the engines are overhauled, but it will be interesting to see.
Finally, it appears that I have a slightly better climb out. Unfortunately, I did not perform a "before strakes" test on this -- so it is subjective, but it does feel that it climbs out a bit faster.
In addiction to the sharp look, I am sure the strakes add some strength to the tail. Thank you for performing a meticulous job of installing these -- I am happy with the results.
