Mattituck's Phil Haponic Explains

Bruce Bohannon's Exxon Flyin' Tiger may have one record that could stand longer than even its time-to-climb and altitude records: it set seven world records on a single flight. While we knew of several of these, and reported on the flight, it was quite some time before even Bruce or his sponsors knew just how dominant his flight was. For your edification (and to let Bruce know that we pay attention), here are all seven records, set during a single flight, on October 22 of last year.

* The old record, 35,497 feet, was also held by the Exxon Flyin' Tiger, in class C-1.b

Of course, it takes a whole lot more than an engine to make these records happen, and we've covered a number of the required factors -- crew, pilot, engineering, weather -- but nobody's going to argue with the fact that it takes a darned good engine turning a darned good prop.

The Flyin' Tiger's engines are built by Teledyne Mattituck Services, and we cornered Mattituck's Chief Inspector, Phil Haponic, at Sun 'n Fun, to tell us about what it took to make such a mill.

Haponic has been with Mattituck 28 years, and has seen a lot of champions. (He built Leo Laudenslager's engines for 15 years.) Power, though, is secondary. Phil told us, "Safety is the big thing. If you dig into one of these [engines] too quickly, it'll fall apart."

The first "build" isn't made of metal; it's on a computer. "It's very close, in terms of most performance characteristics, to the finished engine," he explained. After the computer "build," though, Phil says the fun starts: "Then you have to be able to build the parts -- even to get the parts."

Here's a bit of what goes into Bruce's 555 inch, 355hp engine:

• The crankshaft is reground to lengthen the stroke .100", hence the displacement of 555 cubes. Phil says about six such cranks have existed, through time.
• The cylinders are stock-bore Superior parts, though the piston-to-wall clearance is increased, Phil says, "a little."
• The heads incorporate some special valves: the intakes are special-made, and the sodium-filled exhausts are oversize units, from a slant-valve engine. "They almost touch, as they go up and down," says the master builder.
• Connecting rods are selected to be a close match; then they're precisely matched. "Standard hot-rod stuff," Haponic notes.
• The pistons, which push nearly a 13:1 compression ratio, are slant-valve pistons, with custome-made tops. Special lightweight wristpins are used.
• After all the selection, and at several points in the building, everything gets dynamically balanced.

The turbocharger (not a Mattituck part, and featured in our earlier Bohannon coverage) provides sea-level performance to "26 or 27 thousand feet," according to Bruce.

As for other hot-rod conventions, Phil says, "There's not too much polishing of components -- mostly just what's needed for aesthetics." In other words, the polishing is on the outside of the engine, so people can go "ooh" and "ah," not on the inside...

If there were a breakthrough...

Phil (right) says that development of the current recipe took a little over two years, maybe two and a half, of often-intensive 'part-time' work. The computer helped; but the data the computers generate still need to be translated into metal.

The "breakthrough," if a single point could be tagged, was in the cam profile. A lot of attention to the standard parameters -- lift, timing, duration -- led to some tricky problems in profile, on both opening and closing.

Added to that was the consideration of the unique piston crowns and the special valves -- the geometry was more than a trivial exercise.

Horsepower isn't the whole story.

Bohannon told us, "We run 24-24 most of the time. That's probably 230 horsepower or so."

"Was that enough?" we asked rhetorically, remembering that all those framed records didn't come from a mail-order catalog.

"Yeah -- that, plus a high airspeed," he replied. [The Exxon Flyin' Tiger is one fast machine. Leveled off at 40,000 feet (!), it was quickly indicating 165 knots -- over 320 mph on the ground! --ed.]

What about all the computer design stuff?

With the computer's ability to get close to reality, so quickly, why did it take over two years?

Phil rolled his eyes, but remained polite. "The computer design is close to what you want," he admitted, "but it all takes time... and money. Step, step, step... piece, piece, piece." Mr. Haponic used two dynamometers in the development. One was a more-or-less standard water-brake dyno, like a hot-rod shop would recognize; the other was a prop dyno, where the engine is loaded, not by a water brake, but by actual air, just like in an airplane. Once the initial build is ready, he says, "You experiment. We used two different fuel injection systems, two different servos for the lambda (sensor)..."

The prop dyno was doubly revealing, especially as the flying days got closer. Variable-speed cooling was used during dyno runs, to learn and plot heating/cooling effects, to understand fuel burn and internal temps, and to get as close to actual flight conditions as possible.

Not off-the-shelf

Virtually everything in, on, and around the engine has been specially-selected, specially-worked, and specially-built. The result is not only a safe and reliable engine, it is an engine that has the ability to go out and set records (if properly installed, tuned, maintained, and flown).

There is one other engine like this, and it's packing fifteen or twenty more horsepower, even. Its design isn't identical, though, as its mission profile is very different: it's in a Zivko Edge 540, and its aerobatic future will get surely get coverage in ANN.

As for how you can get an engine like this, and how much it will cost, Phil says that's not a good question for you to be asking. Have your sponsor(s) call Mattituck. What -- you don't have sponsors? Then you don't want to know.

As for Phil Haponic, he says he has dreams, just like everybody else: "What I really want to do is build a 602 [cubic inch engine]. I need a crank..."

FMI: www.mattituck.com