39 Year Dyke Delta build and I thought we were slow!
Persistence pays off
Story and photo by Randy Dufault
Alan White started his Dyke Delta project in 1971 and flew it for the first time this past June.
When Alan White started his Dyke Delta project in 1971 his two children were still small enough to bounce on his knee. They grew up watching Dad work on his project – as did their children.
“Now I can’t even lift my grandchildren,†he said, standing by the now-flying craft parked in front of Homebuilders Headquarters.
White started on the project 39 years and a couple of months ago and first flew it this past June. He chose the delta-winged design for its ability to carry his family at the time, but added, “I also wanted something speedy, and a little different.â€
Trips to AirVenture provided the motivation necessary to keep the project going, but upon seeing a particularly appealing composite constant-speed propeller in 2009, White made a commitment to finish the bird and fly it to AirVenture this year.
“Unfortunately they wouldn’t let me put [the propeller] on the engine I had,†White said. “It required a dynamically balanced crankshaft so I decided I was going to bite the bullet and I bought another engine.â€
The new power plant required a complete reconstruction of the mounting structure, but through diligent effort, airframe and engine were mated in October 2009.
Unusually good springtime weather at White’s northern Wisconsin home allowed him to paint the plane and finish the final preparations for the first flight.
A number of things changed on the plane over the course of the project. One was the fiberglass fuel tank White originally constructed. Concern for what the future of aviation fuel might—or might not—hold caused him to replace it with a hammered out aluminum version.
Another modification is an additional horizontal trim surface mounted to the vertical stabilizer in a cruciform configuration.
“Most of the builders that put on a constant speed prop either have the extra surface, or wish they did,†White said.
His decision to go with the prop occurred about 25 years into the project. It turns out that the exceptionally light Whirlwind three-bladed propeller installation probably would allow the surface to be removed—but White is happy with the flight characteristics as is.
White was not enamored with a typical Dyke canopy installation so he designed a unique mechanism that allows the canopy to pop up and slide forward. A series of pins make for a very tight seal, alleviating a problem other builders encounter when hinging the canopy on the right side.
According to White, performance behind the 180-hp Lycoming O-360 is quite good. Initial climb after a 1,000-foot takeoff run is 1,800 fpm. At altitude he is seeing cruise speeds of 145 to 150 knots pulling 65 percent power and 167 knots at 75 percent.
Some changes are still planned even though the plane is flying. He purchased the current cowl from another builder but believes that his final engine installation will support the reduction in cooling drag that a newly made cowl could bring.
Another change will be the wheels. White is looking for a set of Clevelands to replace his current Goodyear units.
Goodyear wheels were very much in vogue 39 years ago, but the cost of the parts alone for repairing a brake would now almost equal that of replacing the entire wheel.
The final push was a healthy effort as well. White credits a personal 27-pound weight loss to his efforts this past year where, beyond his normal workday, he estimates that he spent another eight hours working on the Dyke. “I guess I skipped enough snacks during late night television,†he quipped.
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