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Flitzer - Nostalgia Now!

By John Morris, EAA 267688

Flitzer D692
Lynn Williams shows off the Teutonic lines of the prototype Flitzer D692. Photo by Mike Vines.

Rolf Steiger climbed gingerly from the gangway into the cockpit of the tiny bright red biplane suspended beneath the bow of the old Schutte-Lanz airship as it plowed its way through the arctic air. They were on a secret mission to survey future refueling stops for German U-boats, but the real goal was to locate the hidden treasure of the Romanovs.

Reaching up to a pistol grip and trigger on the cabane, Steiger squeezed, releasing the diminutive single-seat Doppeldecker to plunge from the mother ship and fly away behind the clattering Haacke exposed two-cylinder engine in the polished bullet cowling. The year was 1926, and Germany was launching secret missions, and secret airplanes, to shape its future.

The red biplane was a Staaken Z-1 Flitzer, built clandestinely in a corner of the mighty Zeppelin repair sheds at Staaken, then Berlin’s main airport. Other models of Flitzer would later be developed as one-place sporting and lightweight fighter-trainers, embodying all that was emotive of the roaring ’20s.

By 1991, the Staaken Z-1 Flitzer had made its way to the Royal Air Force Museum in Hendon, England, where it was on loan as a static exhibit. After the fall of the Berlin Wall, Welsh artist and longtime pilot Lynn Williams, brother of renowned aerobatic champion Neil Williams, became the owner of the prototype Luftschiffparasit, and he wouldn’t say how it came into his possession. But all was revealed after April Fools’ Day 1996. The Staaken Flitzer that had stirred so much interest was a creation of Williams’ fertile imagination, along with the adventure story he was writing that had spawned it. The little red airplane was what would have been, had it been a real airplane from the pages of a historical novel.

The Real Deal
Now plans are available for the 18-foot span wood-and-fabric sport plane; it weighs in at just 500 pounds empty (the prototype is 20 pounds lighter) and can be powered by a Volkswagen conversion or Jabiru or any other engine up to about 80 hp weighing around 165 pounds.
 
Williams’ avowed intent was to design an aircraft that would be economical both to build and to fly. The Flitzer was not meant to be a replica of anything, but a proof-of-concept design that could be adapted into many period airplane look-alikes. However, its Teutonic lines, embodying characteristics of many German aircraft of the 1920s, so captivated the imagination that the Flitzer has become a marque of its own. Beefed-up competition aerobatic versions (the Stummelflitzers), with ailerons on all four wings, can take up to 110 hp, and at least two under construction in the United Kingdom and France are powered by the Rotec R2800 radial. Lightweight versions, such as the Goblin and Meteor, have flown off Williams’ drawing board, and a two-seater prototype is being built in the United Kingdom.
 
To date Williams has delivered 289 sets of plans, and work is under way on at least 60 Flitzer variants worldwide. Performance by all accounts (there have been several published pilot reports) of the basic airplane is both delightful and sprightly, bringing out the Red Baron in all of us, and Williams claims the Flitzer will more than hold its own in a dogfight with a Bucker Jungmann. The engineering division of the British Light Aircraft Association (the LAA, formerly the PFA) has approved the basic design for homebuilding, and Flitzer builders are now awaiting the LAA stamp of approval for aerobatics, for which the basic Flitzer was intended from the start.

Flitzer D692
Baron Ivan Morrisov’s Flitzer will be painted with lozenge camouflage wings, fuselage in the colors of the Bavarian flag, and the tail emblazoned with the skull and crossbones of the Russian ace Kazakov, with whom his illustrious forebear used to fight against the Bolsheviks.

The Project
I fell in love with the bullet-nosed Flitzer at first sight and decided I just had to build one. Where else could one find vintage wings that came with such a long and fascinating history that just oozed nostalgia? One could shape one’s own “history” within the context of that historical novel, with the Flitzer the vehicle—indeed the validation—for whatever role the hero wants to play.

Flitzer
The Baron inspects a Flitzer aileron in the Connecticut Flitzer Werke as Ernst Kessler’s three-cylinder Flitzer Kobold taxies by outside (don’t we wish!).

I determined to resurrect the machine flown in Germany in 1926 and later in the United States by my illustrious forebear Baron Ivan Morrisov, wearing the personal colors he adopted as a flight instructor at the Sportflug GmbH fur Mittelfranken und Oberpfalz at Furth, in southern Germany. And so, in a transplanted pocket of Bavaria in central Connecticut, the Morrisov machine is taking shape. But first I needed the plans. Just as one likes to visit the breeder if one is buying a pedigree dog, the Baroness and I decided to visit Williams and his wife, Margaret, in Wales. After all, I told her ladyship, once we launch the Flitzer project they will likely be part of our lives for a long time, and it would be so much better if we all knew each other. Within hours of knocking on his door he and I were whiling away the evening talking Fokker D.VII manufacturing methods, and the Baroness and Margaret were Turkish belly dancing in the kitchen, so I knew it was going to work.

While there we visited Williams’ Flitzer so I could see one up close (seven have been completed: six in the United Kingdom and one in Australia). One is struck first of all by the presence of the airplane. It stands nearly 7 feet tall, on 17-inch spoked wheels, and commands attention. Walking around it one realizes how small it really is, but sitting in the cockpit one can’t decide whether it’s a big plane or a small plane; it’s just there with everything where it should be, and one is sitting deep within it with one’s eyes level with the top of the fuselage. This airplane is as big as you want it to be!
 
Williams is an artist, and the 34 sheets of plans for the Flitzer are works of art in themselves, laced with cutaways, 3-D views, and much humor. One could frame any sheet and hang it on the wall (indeed, some fans have). The drawings are a delight to study, and once absorbed, leave very little detail design to one’s imagination.
 
Construction Details
The Flitzer itself is a completely conventional 1920s-technology all-wood biplane, with the plans drawn for Sitka spruce and birch ply. The fuselage consists of four longerons with cross braces, plywood covered for immense strength. (Incidentally this also creates a sound box, much as in a guitar, that converts the staccato “snap” of a VW exhaust into a much more classic-sounding rumble). The firewall is built up of spruce, ash blocks, and 2 mm ply on front and back and then glued to the fuselage along with reinforcing gussets and metal corner fittings.

Flitzer D692
The spruce and plywood structure of the wings is quite traditional. The upper wing panels join at the cabane and span 18 feet.

The wings are straightforward with two solid spars with built-up ribs and compression ribs cut from ply and reinforced with spruce. The leading edges are boxed with plywood to form an incredibly strong D-section from the main spar forward. The ribs are designed so that the angle of incidence of 1 degree on the upper wing and 1.5 degrees on the lower is automatically built in. Chord is a mere 32 inches on the lower wing and 34 inches on the top; the upper panels are 9 feet in length, the lower just 8 feet.

Flitzer D692
The first completed upper wing panel. Note the one-piece laminated wingtip bow and solid trailing edge.

Indeed, with the fuselage (minus tail and firewall forward) measuring just 11 feet, the Flitzer can be built in a one-car garage.

Flitzer D692
Fuselage and wings nestle together in the 12 foot by 20 foot Connecticut Flitzer Werke.

Construction time can be reduced by ordering wood and metal “kits,” but forget quick-build! A wood kit comprises lumber cut to size and length, in other words a box of “sticks,” but the metal kit available from Ian Wasey in the United Kingdom is comprehensive and water-jet cut. It is astonishing how many metal fittings there are in an all-wood airplane!

Like most first-time scratchbuilders I started with the fin and rudder, eschewing the “kit” for ordering material as needed from Wicks Aircraft Supply. The learning curve is steep, especially if you haven’t constructed a wood airplane before, with the realization that one must build one’s own jigs and tooling from which to make the airframe parts.
 
Steaming, bending, and laminating become acquired skills, and one has to start somewhere so it might as well be the vertical tail as this encapsulates most of the woodworking knowledge one needs for the rest of the structure. This is the challenge of the Flitzer: while it is a simple, straightforward design, one must learn to approximate all the skills of all the craftsmen in a World War I airplane factory in order to finish it. Luckily one doesn’t need all those skills on the first day, and they are developed progressively.

So is the collection of tools. I built my Flitzer basically with a band saw, a 6-inch sanding disk, a bench-mount press drill, and a hand plane. A router came in handy later on, then a 20-ton press for bending metal, a grinding wheel, and electric sanders. EAA Bleriot builder Ken Terrio introduced me to his Bridgeport mill, and welding I left to the experts. The project will culminate with my workshop equipped as I wish it had been when I started!

Fin and rudder finished, I embarked upon the wings. I used T-88 glue throughout with adhesive and catalyst mixed by weight on my digital scales.

The wings can take a long time because there are four of them. One learns to wrap and glue plywood skins on the job. I found it worked well to soak the skins in the bath, keep them under damp towels while applying glue to the ribs, then install them while still wet—if one can call frenzied coaxing, nudging, and wiggling, followed by judicious stapling with stapling strips, “installation.” The T-88 works fine with wet surfaces, and the plywood dries out nice and tight as a drum. This method worked well on the fuselage, too, avoiding wrinkles that can develop so easily if the plywood is put on dry.

Eventually the project would use 9,000 staples throughout the whole airframe to hold wood in place while the glue set. Every staple was subsequently removed, using a sharpened screwdriver to drive a wedge under them and lever them out.

Tensioning the Wings
The wings involved one of the engineering problems that the plans occasionally mask. The drag and anti-drag wires are specified as “piano wire,” which, it turns out, is a peculiarly English aeronautical term for a particular spec of music wire. Here in the United States the term piano wire is loosely bandied about as a substitute for music wire, but they are not the same! Some are brittle, some will fatigue with vibration—and it becomes next to impossible to sort out which will be suitable. My solution was to buy “music wire” from an aircraft supplier in the United Kingdom who uses it where piano wire is called for.

So to sum up, here’s what I came away with during my “piano wire” purchasing experience: All piano wire is music wire, but only a very limited spec range of music wire qualifies as the old “piano wire.” Today, in the United States, the term piano wire is used generically for the sort of wire you put in pianos, but it doesn’t meet the old “piano wire” specs. The result is that you look up piano wire in the catalogs and think you’re getting the right stuff, but you’re probably not. So to hedge against confusion, I ordered my “music wire” from a particular United Kingdom supplier since he had already ascertained that the spec he carried was an acceptable substitute for “piano wire.” In other words, I have more confidence in a professional aviation merchant’s ability to sort out all of this than I do in myself, so I subordinated to the expert.

The next trick was to learn how to secure the ends of these wires on a lug or turnbuckle. If it was stranded wire, you would loop it back and Nicopress it. A visit to old technology—older Wacos and the Fokker D.VII—shows the wire is merely looped back on itself around a thimble, secured with a ferrule of twisted wire, and the end bent up (easier said than done!). That doesn’t look strong enough, and anyway, you need a machine shop with special tooling to make wound ferrules, as they are in fact oval in shape.

Flitzer D692
Wing drag and anti-drag wires are made from music wire, secured with twin Nicopress sleeves, and attached to these shop-made turnbuckles.

A common Flitzer answer is to apply two Nicopresses to the smooth cable in lieu of the ferrule, even though the Nicopress sleeves were made to work on stranded, not solid cable. To validate this solution I made a test gantry in the grounds of the Connecticut Flitzer Werke, with a Nicopressed cable supporting a dangling rain barrel that was progressively filled with water until breaking point was reached. At 8.35 pounds per U.S. gallon one knew just how much weight the cable could support—and it was in excess of the maximum load the cables would bear according to the stress analysis of the Flitzer.

Flitzer D692
Rain barrels and the gradual addition of water proved the strength of the wing drag and anti-drag wires.

Flitzer D692
The front room of the Baronial hall was commandeered for the trial fit of the lower wings to the fuselage.

Fuselage
Moving on to the firewall, I decided in consultation with Williams that since the 80-hp (2180-cc) AeroVee conversion (with its full complement of bells and whistles) is heavier than the otherwise stock 1600-cc hand-prop VW engine used in the prototype, I should place the firewall 2-1/2 inches farther aft of the location the plans specified for VW variants with rear accessory cases. As with any modification, this caused a chain reaction—the front landing gear legs were repositioned, their angle and lengths both changed; the fuel tank would have to be smaller to fit the smaller space—but the 2180 drinks more gas than a 1600 at full power, so I really needed a bigger tank.

Flitzer D692
The AeroVee engine is seen here inverted on its work stand with exhausts fitted. The entire firewall forward is built on this accurate firewall mock-up, which can be rotated for easy access.

An expanded fuel tank has been designed, and the longeron-firewall gussets altered to accommodate it—all with Williams’ approval. Luckily all the changes were occurring just about on the center of gravity (CG), so there should be no other ramifications. Indeed, Williams designed the Flitzer with the weight masses concentrated close to the CG to ensure fighter-like maneuverability.

Interestingly, the Flitzer does not allow adjustment of the upper wing for CG correction. Williams is adamant that if the airplane is built right, the welded, non-adjustable cabane structure will position the upper wing where it is needed. That leaves just two methods of adjusting CG when the airplane is finished: adding weight in the tail (or the nose) or lengthening/shortening the engine mount. Of the six aircraft flying today none have had their engine mounts altered, and there has been little call for adding ballast.

The standard fuselage is just 22 inches wide (outside dimensions), and a “wide body” Z-21A allows for 24 inches. The Morrisov machine is the standard 22 inches, and sitting in it (yes, we’ve all done that and flown it round the shop!), it fits my 220-pound frame like a glove, but it doesn’t feel cramped at all. I have also lowered my seat by 2 inches so as to sit even deeper behind the already deceptively deep top decking.

Undercarriage
Brakes proved to be another issue. The Flitzer prototype doesn’t have them; it flies off grass with a non-steering tailskid. Operating off tarmac would require a tail wheel and brakes for steering. To the rescue came Ian and Rupert Wasey, whose own Z-21 Flitzer sports a near-invisible fixed Rollerblade (inline skate) on the tailskid and a pair of delightful Wasey-designed and -manufactured drum brakes that keep the period look (they didn’t have discs in the 1920s) while solving the problem of how to anchor a live, bungee-sprung axle so it doesn’t rotate when the brakes are applied. Wasey will build brakes and wheel hubs to order; Rupert reports that ground handling is excellent.

Conclusion
Construction of the Morrisov machine has now entered its fifth year, and as far as is known, it is the most advanced in the United States. The current challenge is painting four-color, German night bomber lozenge camouflage on the eight wing surfaces, and the skills acquired in doing so will be called upon to spray the fuselage in its Bavarian blue and white diamond color scheme.

Flitzer D692
The current project is painting the wings in German dark night bomber lozenge camouflage, representing the fact that German sport plane manufacturers used up surplus stocks of WWI printed fabric on their postwar creations.

The environmentally friendly Stewart Systems waterborne paint products is being used for covering and painting; the high volume low pressure (HVLP) spray equipment leaves little overspray, and of course, the waterborne polyurethane paints can be cleaned up with water.

Flitzer D692
Here the fuselage and one lower wing are covered and painted with Stewart System’s UV blocker, while the second lower wing awaits its turn.

First flight? I tell everyone now, on any day, “within a year!” After all, even Boeing can’t say when the 787 will fly for the first time, and that project is two years late! Secretly I hope to fly next year (2010) and debut the Flitzer at Oshkosh in 2011.

One of the biggest surprises in building the Flitzer has been the support and camaraderie of the worldwide Flitzer builders forum on the web, which must be one of the most energetic and knowledgeable around. The prime energy comes from Lynn himself: he seems to monitor it 24 hours a day and responds to queries within hours. He’s quite protective of his designs (even offering to design period color schemes for builders), and while he welcomes improvements, he strongly discourages builders from straying too far from the basic philosophy. This approach has resulted in “approved” changes and design developments by Williams himself such as a deeper fuselage for taller pilots and a slightly bigger, longer range Continental-powered Flitzer for “U.S.-sized” pilots who need to fly farther than from one side of the United Kingdom to the other.

Several Flitzers are now approaching completion in the United Kingdom, France, Australasia, and Slovenia, and Williams is confident the fleet will double in the next couple of years. The Morrisov machine will add the United States to the growing list of countries as more builders embrace this 80-year-old modern design.

Flitzer D692
The Baron and Baroness celebrate Christmas at the Connecticut Flitzer Werke.

Flitzer D692
Baron Ivan Morrisov poses with the Flitzer fuselage at its inaugural rollout. Its stature and steep ground angle are both apparent.

John Morris is editor in chief of Aviation Week Show News magazine (www.AviationWeek.com/shownews). His restored 1952 Auster 6A won an award for Outstanding Limited Production aircraft at Oshkosh 1986. You can contact him at morrisoff@aol.com.

Learn more about Flitzers at www.FlitzerBiplane.com.

View the Morrisov machine (and download Connecticut Flitzer Werke newsletters) at www.FlitzerBiplane.com/JohnMorris.shtml.

See the Flitzer-Builders Yahoo group at http://Groups.Yahoo.com/group/Flitzer-Builders.

 

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