UPF-7 Maximum Allowable Takeoff Gross Weight Increase STC

After two years of effort, American Waco Club member and UPF-7 owner John Corradi is pleased to announce that he has obtained an STC (Supplemental Type Certificate) to increase the maximum allowable takeoff gross weight of a UPF-7 equipped with the 275hp Jacobs engine and constant-speed prop to 2880 lbs., from 2650. John is offering the STC for sale to anyone interested.

“When I had the Waco re-done two years ago by Centennial Aircraft Services of Battle Creek, Michigan (an affiliate of Waco Classic, the builders of the new F-5) the 275 Jake was first on my list of desired improvements,” says John. “It’s expensive, but that engine makes a hot rod of an F-7!” But the conversion also increased the empty weight of the airplane a tad. “With the wheel pants, engine cowl and aft canopy, I was over gross with just full tanks and myself onboard.”

So John started looking at the possibility of obtaining an STC to increase the takeoff gross weight. Through contacts he made at the FAA while working for Ken Hyde on the Wright Experience, John was encouraged to press on. Living near the Smithsonian, where the Waco factory records are preserved, was a happy circumstance, for John was able to make numerous trips to the Silver Hill, Maryland facility to pore over original flight test data, manufacturing records and engineering test reports.

“Turns out that the factory had tested the UPF-7 fuselage and wings to 2880 lbs., and obtained an STC for a float plane version with a max takeoff gross wt. at that number, so I figured all I had to do was get a DER (FAA Designated Engineering Representative) to sign off on the landing gear, and I ought to get the STC,” says John. “NOT! At one point, I had no less than five (5) DER’s on the payroll, and had to fly two test flights with a Designated Flight Test Rep, but we got it done!”

Now John is offering the STC to others. “If you’ve ever wondered about the consequences of routinely operating your airplane over the maximum allowable gross weight, give me a call,” said John. “I figured that if I ever blew a tire on landing, or did something else stupid and wound up in the weeds, the first thing the Feds are gonna say is ‘The pilot was negligent in that he was operating the aircraft in excess of the maximum allowable takeoff gross weight.’ Bye-bye insurance; so long Waco. Arriverderci ticket. Everyone who flies a Waco deals with this over-gross issue, of course, and maybe you’re comfortable with it. But if the peace of mind that comes from knowing that you’re NOT illegal every time you take your neighbor, or spouse, or kids for a ride in your gorgeous bird matters to you, let’s get together. I’m not looking to get rich, but if a few of the folks who fly an F-7 with the Jake engine and Hamilton Standard 2B20-9 prop buy this STC, I’ll recover some of my costs.”

John can be reached at 540 937-5371; cell 540 272-5377. Or email corradis@earthlink.net. Please visit his website at www.blueridgebiplanes.com.