HP-24 Project

Update 19 February 2008: Steve McQueen!

Been doing a little traveling lately, and getting in a few shop hours here and there. I went out to the SSA convention in ABQ. Hung out with Brad and Noel Wade and Cherokee II aficianado Tony Condon. Chatted with Dick VanGrunsven, the whom I'll see again in a couple week when we make a run for the border to drop off Brad's carbon HP-24 fuselage, pick up my flaperon molds, pick up Steve's RV-8 finishing kit, and also pick up his Lycoming engine. Chatted with Einar again. Looked up Dave Nadler, chatted about the amazing Antares electric self-launcher, and learned something of the history of the SN10. Had a good time yammering with Danny Howell and the lighthawk team. Went out to see the Southwest Soaring Museum, but it was closed. Had a look at some of the leftover Zuni tooling, which was weathered beyond utility but yet yielded some good ideas. Got a tour through Robert Mudd's shop out at Moriarty, and saw some interesting LAK and Genesis parts, and also Robert's Antonov glider with jeweled-precision movements like a Russian copy of a Swiss watch. I also got a tour of the Albuquerque Soaring Club hangar, and finally saw a Salto in person. It seemed larger than I'd expected.

Oh - I also finally had a break in my luck with rental cars. At ABQ I got a free upgrade from 4-door econoblob to a new Ford Mustang. Slushboxed, to be sure, but with some of the best transmission/engine management integration I've yet experienced. You'd be tearing up through the gears near WOT, and at the shift the EMputer would automatically spill revs to synch the next gear and then ramp the torque back on. It was too, too like the Bullitt soundtrack (they overdubbed it with GT40), minus the six hubcaps and the omnipresent green Beetle. I was sooo glad I'd brought a leather jacket and Aviator shades.

Overall, I give the Mustang a passing grade in the retroclassic class. Though the engine sounded lumpy and unrefined at idle, I think that's an act put on by the engine tables. It pulled smoothly and evenly, with good throttle feel. The brakes and steering seemed well enough matched. The GPS antenna on the trunk put me on notice to play nice with it, but it felt noseheavy-ish, like it would go understeer near its limits. Rapping on the exterior panels shows that there's a great deal of plastic to this beast, and where it's steel it's fairly thin steel and not particularly well supported. But, hey, this is not a car built for the ages. It is a car that casts itself and deserves to live. It's a car such that, by the time it's a problem it's somebody else's problem.

Turning a rod of black Delrin into a baggie full of wingtip wheels to fit a custom fairing that Brad is manufacturing.

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At the SSA convention. Here's a Diana II Bug wiper. Does anybody really use bug wipers? Is the band-aid in this photo a visual Freudian slip? Do tell.

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Diana II gear, looking up from the rear. Note that there's no aft yoke in the traditional sense. The swing of the forward yoke is restrained by a discrete downlock, the hook of which you see engaging a cross-tube and attached to an actuation cable.

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The novel though simple pivot of the Carat gear. Note that the pivot axis lies in the plane of a level-flight waterline.

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Carat lower rudder hinge. Note the embedded weldment to support the hinge. Note also the rod end attachment for one of two hydraulic dampers that drive the tailwheel steering.

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Inboard end of the LS10a flaperon. Note the reflection of the overhead lights showing the wing contour lines. The interesting thing here is how the side-of-body fairing aligns with the flaperon at the -5 or so setting. Also note how far inboard they extend the hinge line crease of this setting. I'd have been inclined to fair in the crease more than this, but hey, what do I know?

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The generous ventilation hole at the nose of the DG1000.

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A picture of a slide from Einar Enevoldson's presentation on the Perlan project. This is a mockup that Greg Cole built of the Perlan Phase II pressure cabin. Note they've taken a page from the Rutan playbook, using many relatively small transparent areas arrayed around two larger plug door openings.

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The outboard end of the Diana II flaperon. The indistinct dark band under the mylar denotes the hinge axis. Note that the flaperon tip chord is only about 1.25". Such small parts can be devilishly hard to make well.

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The Diana II horizontal tail with the forward fairing removed to show the elevator drive and probe connections.

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The outboard end of the Diana II flaperon, with the winglet removed.

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Two photos of the Stemme S10 mid-fuselage with the center wing removed (which removal required the labors of four men and a custom-made gantry). It's nice to see them keeping things simple and straighforward.

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They wouldn't tell me what the gray double-hemisphere box does. I'm not too sure I want to know. There are so many jokes one could tell it's hard to know where to start.

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This is the iron bird fixture used to align the wing attachment and lift fittings of the Zuni wings.

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Zuni fuselage molds. Note that the mold embodies the transparency area of the canopy, which we made a conscious decision not to do with the HP-24. George used an interesting trick on the Zuni and probably also on the Zia: When developing the fuselage plug, he first made a free-blown canopy transparency, and then lofted the fuselage plug to fit the transparency. That gave him a high degree of confidence that he could achieve a good fit between fuselage and transparency even without a precision stretch-molded canopy.

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A broken SZD-48 or so. The camera lost power just after this photo, when I was trying to get a photo of the place where the spar butt was broken off of the right wing at the root rib. That break revealed that the root ribs on this ship are of a one piece design that embodies both forward and aft areas. The rib is notched to accommodate the fiberglass roving spar caps, which get shear-wrapped together after the upper and lower skins are joined. Seeing as how most if not all of the wing shear is extracted at the lift pins, there's a lot of sense in that approach.

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My rented Mustang.

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At the shop on Tuesday 19 February. We'd joined the upper and lower stabilizer skins about six hours prior, and now we're trimming the squeeze-out while it's still a bit rubbery.

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This thing always seems way too big, but it's span and area put it right in the tail volume cloud with other ships of its size and weight. It looks a lot smaller with Rick Walters standing next to it. After this photo we set it back into the mold to finish curing.

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Homebuilt aviation is not for folks who don't try things at home.

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page updated 19 February 2008 all text and graphics copyright (c) 2007 HP Aircraft, LLC