Photos: John Slemp
It is called the Gold Lindy, a 7-pound statue of Charles Lindbergh that is awarded to the absolute best kitbuilt aircraft at AirVenture every year. Every Gold Lindy is inscribed with a quote from Charles Lindbergh: “Progress and quality are inseparable.” Those are not just inspiring words on a gold plate. Every judge at AirVenture uses them as a guide star, searching for aircraft that are not only beautifully built but are also innovative, pushing the boundaries of design and performance.
Darryl Hudec, the man who was awarded the AirVenture 2023 Gold Lindy for his stunning and beautiful F1 Rocket, did not set out to win that award when he began construction in 2018. Looking at his impending retirement from a career as a Southwest Airlines 737 captain, Darryl concluded that it was time to satisfy his long-felt desire to build his own aircraft and fly it wherever he desired. It was at that point that he decided to go in for all or nothing. He would build the absolute best kit that met his desires, and he would build it to be “the best that I could possibly make it.”
Choosing the right kit was a combination of determining the mission and sorting through the alternatives. Darryl knew that he wanted a fast and roomy two-place aircraft that could take him and his beautiful wife, Minya, on post-retirement adventures. He also desired sporty performance that would allow him to yank and bank far beyond the restrictions of airliners. Darryl went to Sun ’n Fun in 1989 and saw the F1 Rocket. It was love at first sight. Subsequent research revealed that Rocket construction would present certain challenges, but Darryl was undeterred.
The Rocket Saga
The Rocket story began in the 1980s when California builder John Harmon took a Van’s RV-4, clipped the wings, changed the forward longerons and bolted a rip-snorting 250-hp Lycoming 540 to the nose, creating the Harmon Rocket. Later, Mark Frederick redesigned the Rocket by repositioning its gear, changing the motor mounts, widening and lengthening the fuselage and increasing fuel capacity to 52 gallons, resulting in the F1 Rocket. Frederick took the design to HPI in the Czech Republic to begin making kits. Sadly, the exchange rate between the Czech koruna and the U.S. dollar tanked, leading to halted production and an F1 program in limbo. Enter Vince Frazier, who made a deal with Mark Frederick to resurrect the F1. Vince cranked out 10 tail kits and the F1 was back in business. One of those tail kits was sold to Darryl Hudec, who drove from his home in Atlanta to Evansville, Indiana, to pick it up.
Although Darryl had never built an aircraft before, he had an interesting background. Long before he flew Boeings for a living, he started his aviation career right after high school as a Coast Guard aviation electrician. Based at the San Francisco Coast Guard Air Station, Darryl saw a “Learn to Fly” ad for a flight school in nearby Hayward, California. Not possessing the actual funds necessary to fuel a flight instruction program, Darryl called the owner, offering a deal to trade maintenance for instruction. The owner was not interested. Undeterred, Darryl drove to the flight school to make his case to the flight school owner face to face. Bemused, the owner told Darryl that if he could fix the cowl flaps on his Cessna Skymaster (a squawk that had eluded all of his current A&Ps), they would have a deal. Two hours later, the cowl flaps were functioning perfectly and Darryl was on his way to a successful and fulfilling career as a pilot.
After his stretch with the Coast Guard, Darryl embarked on a storied career, flying pipeline patrols in Texas, a hot-shot oil field charter in a Cessna 206 and finally catching on as a commuter pilot with Rio Airways, out of Killeen, Texas. From there, Darryl progressed to 727 captain with Air Atlanta. When they went out of business, Darryl flew cargo 727s for Kalitta Air and later DC8s for Emery Air Freight. He then returned to passenger carriers when he signed on with AirTran, flying 737NGs. Later, AirTran was purchased by Southwest Airlines and Darryl flew with them until he retired in 2018.
Beginning To Build
Having purchased his F1 tail and wing kits, Darryl resolved to build as perfect an airplane as he was capable of doing. Darryl had not actually worked as a technician on an aircraft for decades. He had virtually no experience with sheet metal or composite construction. He quickly signed up for an EAA sheet metal class in Seattle and later for an EAA composite class.
Darryl started with the wings, building jigs, setting the spars and ribs and then riveting the skins. Although riveting came naturally, Darryl made perfection his goal, never failing to drill out a rivet that was not up to his high standards. Wing construction took one and a half years. After the wings were completed, Darryl began working on the tail. Well into tail construction, Darryl discovered that the top rudder rib was a fraction of an inch too wide, making it impossible to trail flush from the vertical stabilizer. Most other F1 builders just accepted the fit and built it that way. Darryl conferred with Vince Frazier, who recognized the issue, redesigned the rib and gave Darryl the new part. Tail construction took three months.
After his retirement, Darryl dedicated himself to full-time construction at least 7 hours a day, six days a week in his 1800-square-foot workshop. F1 construction was totally unlike modern Van’s kits. Darryl had to source hardware, rivets and fittings. There was no matched-hole construction. The F1 fuselage kit consisted of formed bulkheads, internal floor ribs and top stringers. Darryl had to source, cut and drill the skins himself. Once the fuselage skins were fabricated and drilled, they would be clamped over the bulkheads, backdrilled and Clecoed into place, the way RV aircraft were constructed in the ’70s, ’80s and ’90s.
During fuselage construction, Darryl happened onto a hack designed to make skin panels perfectly flat. Usually, riveting on a wing or fuselage skin results in subtle indentions in the skin, no matter how carefully the rivet is driven and bucked. However, if you take a ½-inch dowel, sharpen one end to a point like a pencil and then drill a hole in the point to the width of the shop head of a driven rivet, you now have a tool you can use to hammer out those subtle indentions. All you do is place the pointed dowel over the shop head of the previously driven rivet and use a small ball-peen hammer to tap out the skin from the back until it is totally flat on the outside surface. Darryl’s son-in-law, Alex Blagojevic, was looking for a way to help on the project when Darryl showed him this tip. After that, Alex was a man on a mission, taping out every fuselage rivet and checking for flatness with a steel ruler. The result was a fuselage with billiard-table-flat skins.
Small Details Make a Big Difference
Darryl deviated from normal construction with the F1’s canopy skirt. The plans called for an aluminum skirt fastened with nuts and bolts. Darryl surveyed the canopy skirts on other Rockets and was not satisfied with the fit or finish. Scrapping the aluminum skirt, Darryl set out to fabricate a better fitting and looking skirt out of carbon fiber. Utilizing fiberglass rod from the aviation department of McMaster-Carr and gutter flashing and box tape from the aviation department of Home Depot, Darryl constructed a mold for the skirt. He then laid up six layers of carbon fiber cloth over the mold to get the shape and fit he desired. Both the canopy and the skirt were affixed to the canopy frame with Sikaflex adhesive to prevent stress cracks in the canopy. Following countless hours of filling and sanding, the canopy and canopy skirt were finished. The whole process took three months. Darryl also spent several weeks lining up the canopy rails so that the canopy would slide open and closed effortlessly. One judge at Oshkosh commented that it was the smoothest sliding canopy he had ever witnessed.
One challenge faced by tandem aircraft builders is the tendency of a canopy to float during cruise flight, resulting in nasty drafts in the cockpit. Darryl addressed this issue by taking the copious amount of time necessary to ensure a very tight fit between the canopy skirt and the fuselage. He also recognized that part of the problem was caused by the cockpit being pressurized by flow from the air vents. His good friend Jim Newman remedied that problem by designing and 3-D printing two outflow vents that replaced the inspection plates located on the fuselage underneath the horizontal stabilizer. In flight, these two vents promote an even flow of air from the cockpit ventilation system all the way through to the back of the fuselage, preventing the fuselage from being pressurized and the canopy being forced away from the fuselage.
Darryl redesigned the entire cockpit vent system. He did not like the look of a vent intake on the side of the fuselage, so he moved it to the bottom of the wing. To cure the common problem of restricted airflow to the passenger in the back seat, Darryl fabricated special ducts out of carbon fiber to fit between the spar and the aileron push tubes. Jim Newman 3-D printed 2-inch tubes, then Darryl applied carbon fiber bidirectional cloth (bid) to the inside of the tubes using a balloon to pin the layup to the molds. After curing, he deflated the balloon and removed the carbon fiber tubes from inside the molds. The back-seater has two ventilation ducts, one for cool air and one for heat.
To address the tandem aircraft’s issues with access to avionics and wiring behind the panel, Darryl used a hint from another Rocket builder to construct the windscreen and boot cowl so that it is totally removable. Utilizing 76 screws and nut plates, the entire boot cowl and windscreen, from firewall to cockpit, is removable in one piece, eliminating the need to work on avionics while lying on the cockpit floor in some impossibly contorted position.
Not happy with the look or fit of off-the-shelf wing root, tail and landing gear fairings, Darryl redesigned and fabricated all of the above from scratch out of carbon fiber. Using packing tape and clay, he worked the clay until he got the desired shape and fit. He would then lay up the carbon fiber over the molds, split them off after curing and then begin the laborious process of filling and sanding until the finish was perfect. Darryl took two and one-half months fabricating the landing gear and tail fairings alone. He made the highly visible wing root fairings from one piece of carbon fiber held on by only two exterior screws and several more screws fastened from the inside of the fuselage so that they would not show.
Rocket Power
The thing that sets the F1 Rocket apart from the similar appearing RV tandem aircraft is the big kahuna in the power barn, usually a 260-hp Lycoming IO-540. Darryl’s engine has a story. He bought a 2800-hour run-out AEIO-540 removed from a Royal Jordanian Air Force Slingsby Firefly trainer. He then completely disassembled the engine and sent it out to DivCo and Aircraft Specialties in Tulsa, Oklahoma. After receiving numerous boxes of yellow-tagged parts back from Tulsa, Darryl took them and several new parts (Superior cylinders and 9:1 pistons and a new Airflow Performance fuel injection system) to Watson Aero in Louisville, Georgia, where he and IA James Watson reassembled everything into a finished engine.
Darryl’s F1 engine compartment contains several innovations. His Airflow Performance fuel injection system sports two “turbo nozzles” that pressurize the injector bodies, preventing siphoning (and uneven fuel delivery) caused by low pressure in the injector bodies. Darryl also chose to install an SDS Electronic Ignition when he found out that it utilized regular NGK auto plugs and Volvo coil packs, both of which can be sourced in a pinch at any local Autozone. Darryl also decided he did not like the use of push/pull cables for engine accessories, so he designed a control system for the ram air intake control and the oil cooler door utilizing electronic linear actuators from Actuonix. He also used those same linear actuators to control cabin heat and rudder trim.
Darryl spent over two months redesigning and constructing the engine cowling and plenum. The two-blade Whirl Wind prop he selected for the engine had an interference problem with the cowling so he extended the prop forward by 1 inch. While in the neighborhood, Darryl increased the cooling air inlet diameters from 5.5 inches to 6 inches, requiring all new cooling coupling rings and a rework of the entire front of the engine cowl. He then set to work on the plenum, which did not fit to his liking. Using the old plenum as a form, Darryl fabricated an entirely new plenum out of carbon fiber, which he worked, reworked and reworked some more until it came out perfect.
Rather than hang the oil cooler off the rear baffling of the engine (many report baffle cracks caused by the weight of the oil cooler and the movement of the engine), Darryl decided to mount the oil cooler on the upper center of the firewall and fabricate carbon fiber ducts to direct cooling air from the plenum to the cooler. In the process, he also had to design and fabricate the brackets necessary to hold the oil cooler core and the cooling ducts, and to regulate air flow to the oil cooler.
Finishing Touches
One challenge of all aluminum aircraft builders is the method of fastening composite parts to aluminum parts. Darryl decided to forego the use of quarter-turn fasteners for the cowling because they interrupted the sleek lines of the ship. He utilized #8 stainless steel screws and nut plates instead of the quarter-turn fasteners. Originally, he planned on using Tinnerman washers under all of the screw heads on the aircraft, including the wingtips, boot cowl and fuel tanks, but he decided that they were too big and clunky. He then cut down 400 Tinnerman washers to 0.485 inch on his home mill, one at a time (an extremely tedious and time-consuming adventure), so that they would fit flush under the #8 screw heads. In the end, the painter decided that even these cut-down Tinnerman washers were too thick, so they were deleted.
When it came to selecting a paint scheme, Darryl deployed his secret weapon, wife Minya, to collaborate with Evoke Aircraft Design out of Gadsden, Alabama. Minya, who has a great flair for design, surveyed hundreds of aircraft paint schemes at Oshkosh and Sun ’n Fun. Wanting to break away from traditional red, white and blue schemes, she settled on a palate of copper, bronze, silver and white. Minya worked with Evoke’s Jonathan McCormick and his staff for over one year before they finalized the paint scheme. One interesting feature of the paint design is the placement of a gold crown and garland on the turtledeck. Many judges and other observers at AirVenture inquired about the story behind the symbol, but Minya relates that it is there just because it looks good. Friends encouraged her to make up a good story (for example that she is the direct descendent of Charlemagne), but she deferred.
The stunning interior of Darryl’s F1 was fashioned by Kyle Henley of Distinctive Aircraft Interiors in Atlanta, Georgia. Kyle and Minya worked on the interior design for almost a year, trying to make it look like it came from a Maserati. Kyle was a true professional, remaking the front seat three times and the rear seat twice so that they would come out perfect. The result is truly evocative of a fine Italian sports car.
The road to Grand Champion would not have been complete without a suspenseful ending. As AirVenture grew closer, time pressure intensified. Darryl took delivery of his F1 from Evoke’s paint shop one week before the show. He then flew it directly to Distinctive Aircraft Interiors for final installation of the full interior. Darryl then had to paint the interior of the canopy and windscreen to complete his project. He literally flew to Oshkosh on the Friday before the show with the paint still curing in the cockpit.
Showtime!
As previously stated, Darryl did not set out to build his F1 to win Grand Champion. However, Vince Frazier knew that Darryl’s plane was truly special and arranged for him to park it in front of Team Rocket’s display at AirVenture 2023.
As he was flying up to OSH, Darryl thought that all the frantic preparation to get the plane ready for AirVenture was finally over and that he could spend a week resting from his labors and enjoy the show. He could not have been more wrong. What Darryl didn’t know, and what most people don’t know, is that getting your aircraft judged at AirVenture on the highest level is a full-time job. The judges do not set an appointment and come to judge your plane all at one time. They come and go in groups of two to 10, often returning several times to reconsider certain aspects of each entry. A builder who is truly in the running for a major award must sit with his or her aircraft all week, awaiting the unscheduled and unannounced visits by each group of judges. Darryl had to remove the engine cowling of his F1 countless times during the week, fearful that he would damage his brand-new paint job. He also had to be available to answer any questions about his build. Many judges seemed impressed by this first-time builder’s attention to detail and his willingness to design, redesign and fabricate each part, often several times over.
Kitbuilt Grand Champion
As is evident from the title to this article, Darryl was awarded the Kitbuilt Grand Championship Award at AirVenture 2023. Darryl humbly accepted his Lindy during the ceremony held at the Homebuilt Hangar on Whitman Field amid laughter, tears and toasts from his friends and wife, Minya. After returning to Atlanta, Darryl and Minya began to deploy their Rocket as God intended. The following month, they embarked on a cross-country trip from home base KLZU in Lawrenceville, Georgia, to the last Reno Air Races, Yosemite National Park, Sequoia National Park, Mount Rushmore and Crazy Horse, and finally back home, taking the better part of two weeks (all at 200 knots).
The following April, Darryl went to visit the Sun ’n Fun Fly-In in Lakeland, Florida, for a one-day visit. Upon landing, a gaggle of judges asked him if he wanted his Rocket to be judged. Darryl knew he would have to fly out that same day to avoid weather and declined. Undeterred, the judges said they could judge his aircraft right then and there. Darryl relented and a few days later he was awarded the Sun ’n Fun Grand Champion Kitbuilt award. The Sun ’n Fun plaque now resides next to the Lindy.
In 2024, Darryl and Minya flew the Rocket back to AirVenture. EAA honored them by parking the plane in the Homebuilt Hangar, where Darryl won his Lindy 12 months earlier. Not having to worry about judging or scrounging parts, he and Minya were able to tour and really enjoy the show. Afterward, they embarked from OSH on another Rocket adventure, this time to Calgary and Banff, Canada, and then over to Arlington, Washington, to see family.
The Rocket is not only a cross-country machine. Darryl has enjoyed light aerobatics and is learning the intricacies of formation flying from the very active homebuilding community in Peachtree City, located south of Atlanta.
In the end, this Grand Champion was the result of Darryl’s simple commitment to approach each aspect of design and construction with the resolve to make it as perfect as he was capable. If that meant fabricating a part over and over, it was simply a part of the job and not a frustration. It was Darryl’s full-time job for the better part of five years. His reward is that he gets to own and fly a truly exceptional aircraft that does everything he wants it to do and takes him and his wife to any place they want to go, swiftly. Oh, and he also got a really nice 7-pound statue of Charles Lindbergh.
