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An Airplane That's (Photo by Jack Cox) by Jack Cox >ACK IN THE heyday of the go-kart and micro midget mania, Wayne Ison (EAA 13187) was into the scene up to his ear lobes just as much so as he is involved with home- built airplanes today. Somehow, be- tween building, maintaining and racing his own karts at tracks all over the upper mid-west, he even found time to write the "how to" go-kart articles for Science and Mechanics magazine. It was tremendous fun for a time, Wayne says today, but as com- petition grew hotter sophistication and its hand-maiden, added costs, started entering the picture . . . and soon the fun was evaporating at about the same rate as the blue smoke from those screaming little two cycle mills that propelled thosejust barely guided missiles. 50 JANUARY 1975 Instead of folding his tent and fading away into the night, Wayne fought back. In order to bring back the fun, close competition and low cost, he succeeded in forming the "West Bend Class - Bushings Only" category. This gave the beginner a chance to get into kart racing at a level of mechanical sophistication that was easy on his wallet and sim- ple enough so as to serve as a good starting point on the learning curve involved in successfully operating, tuning and overhauling the two cycle engined karts. Once a racer had mastered the West Bend jobs and still wanted more, he could pro- gress to the faster, more expensive hardware . . . and his basic training would not have cost him his life's savings. This experience made an indelible impression on Wayne Ison and was carried over to aviation once he be- came involved with EAA and home- building. He restored a Rearwin Sky- ranger about ten years ago and start- ed a Fly Baby but sold the fuselage before it was completed. Wayne en- joyed flying the Rearwin and found the crafting of the Fly Baby satisfy- ing . . . but somehow all this just didn't fill the bill. While sorting out in his mind all the plusses and minuses of his aviation career up to that point, he took time off to do some REAL homebuilding — a new house for his family. Wayne is a mechanical engineer for Keltec in Elkhart, Indiana. His workaday activities involve designing industrial floor maintenance equip- ment floor polishers, cleaners, rug shampooers and the like. He is com- fortably settled in his job, his new home and the life of his community. Flying, for him, is strictly a recrea- tional activity. Despite having learn- ed to fly at Three Rivers, Michigan under the G.I. Bill quite a number of

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Airplane PDQ

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  • An Airplane That's

    (Photo by Jack Cox)

    byJack Cox

    >ACK IN THE heyday of thego-kart and micro midget mania,Wayne Ison (EAA 13187) was into thescene up to his ear lobes just asmuch so as he is involved with home-built airplanes today. Somehow, be-tween building, maintaining andracing his own karts at tracks all overthe upper mid-west, he even foundtime to write the "how to" go-kartarticles for Science and Mechanicsmagazine. It was tremendous fun fora time, Wayne says today, but as com-petition grew hotter sophisticationand its hand-maiden, added costs,started entering the picture . . . andsoon the fun was evaporating at aboutthe same rate as the blue smoke fromthose screaming little two cycle millsthat propelled those just barely guidedmissiles.50 JANUARY 1975

    Instead of folding his tent andfading away into the night, Waynefought back. In order to bring backthe fun, close competition and lowcost, he succeeded in forming the"West Bend Class - Bushings Only"category. This gave the beginner achance to get into kart racing at alevel of mechanical sophisticationthat was easy on his wallet and sim-ple enough so as to serve as a goodstarting point on the learning curveinvolved in successfully operating,tuning and overhauling the twocycle engined karts. Once a racerhad mastered the West Bend jobsand still wanted more, he could pro-gress to the faster, more expensivehardware . . . and his basic trainingwould not have cost him his life'ssavings.

    This experience made an indelibleimpression on Wayne Ison and wascarried over to aviation once he be-came involved with EAA and home-

    building. He restored a Rearwin Sky-ranger about ten years ago and start-ed a Fly Baby but sold the fuselagebefore it was completed. Wayne en-joyed flying the Rearwin and foundthe crafting of the Fly Baby satisfy-ing . . . but somehow all this justdidn't fill the bill. While sorting outin his mind all the plusses and minusesof his aviation career up to that point,he took time off to do some REALhomebuilding a new house for hisfamily.

    Wayne is a mechanical engineerfor Keltec in Elkhart, Indiana. Hisworkaday activities involve designingindustrial floor maintenance equip-ment floor polishers, cleaners, rugshampooers and the like. He is com-fortably settled in his job, his newhome and the life of his community.Flying, for him, is strictly a recrea-tional activity. Despite having learn-ed to fly at Three Rivers, Michiganunder the G.I. Bill quite a number of

  • years ago, he is still a low time pilotand it's rare he flies anything largerthan a Cessna 150.

    In a word, Wayne Ison is a living,breathing stereotype of the typicalEAA member . . . up to a point. Hediffers from many of us in that he hasthe self discipline to coolly analyzehis dreams and his real needs andcome up with a plan of action thatcontains a nice balance of both thathe can live with. Some of his con-clusions about himself were that hedid not need a fast, expensive to main-tain, cross country airplane. This ruledout most of the store bought fleet.What he really wanted was some-thing that was fun, easy to fly andsomething that would satisfy his needto create, build and tinker with thispretty well spelled "homebuilt."

    After a long look at the do-it-your-self world Wayne came to the furtherconclusion that what he had seenhappen in go-karting was also hap-pening in aircraft homebuilding alot of new designs were becomingmore complicated, more expensive,thus making it harder for the averageperson, particularly a rank beginner,to break into the game. He had noquarrel with any design or designer he thought the variety of designsavailable to builders was tremendous.It's just that he did not believe any ofthem started on a simple enoughlevel.

    Characteristically, he set out to dosomething about the situation . . . hewould design his own airplane.

    PDQ-1Wayne's first effort might be de-

    scribed as an attempt at the absoluteminimum powered airplane, a VWpowered machine with nothing morethan a couple of lengths of aluminumchannel bolted together like a bedframe to serve as a fuselage; to thiswere attached his left over Fly Babywings and a rudimentary tail section,all strung together by a cobweb ofaircraft cable. The pilot's seat wassuspended from the bed frame fuse-lage and the VW engine was quiteliterally sitting in his lap. Named thePDQ because it was this sort ofun-Sanforized Bleriot was flown upand down a runway in ground effecta number of times, but its greatestcontribution was as a trial horse forWayne's ideas. He learned a lot frombuilding the PDQ and came to rea-lize the direction in which he wouldproceed from it. The engine from thePDQ was later used to power anexperimental Parafoil, but was re-turned and bolted back on the ori-ginal airframe in time for it to bebrought to Oshkosh '74. The planewas displayed as the PDQ-1 be-cause now there was a PDQ-2.

    (Continued on Next Page)

    The PDQ-1 at Oshkosh 74.(Photo by Dick Stouffer)

    Designer Wayne Ison holds up the tail of his PDQ-2 soEAA photographer Lee Fray can shoot a close-up of thetwo cycle Rockwell JLO engine.

    SPORT AVIATION 51

  • PDQ . . .(Continued from Preceding Page)

    PDQ-2Started during the Christmas holi-

    days before the 1973 Oshkosh Fly-In,the PDQ-2 was completed in just fourmonths of steady evening and week-end work. About the only thing aroundwith a simpler fuselage than thePDQ-1 was the Bensen Gyrocopter so, the fuselage of the PDQ-2 wasmodeled after it to a great extent;in fact, the 2 inch square, 1/8 inchwall thickness 6061-T6 main fuse-lage members were purchased from aBensen dealer. One 41" length waslaid out as a keel and a second piece40" long was cut to serve as a verti-cal mast rising at a 3 rearward anglefrom the keel. 13 inches up the keela 74 inch tail boom was made to ex-tend straight aft, braced with twolengths of 1 inch O.D. x .065 6061-T6 aluminum tubing, one from thetop of the mast down to the boomand the other from the aft end of thekeel up to the lower side of the tailboom. And that, by golly, was it everything else, like wings, engine,seat, wheels, tail, fuel tank, etc.,attaches to this super simple frame.A professional welder was paid $20to heliarc the 5 pieces of aluminumtogether after Wayne ran a littlecost/weight analysis which revealedthat the aircraft bolts, 4130 gussetplates and the time necessary to mea-sure for and drill bolt holes wouldcause the frame to be heavier, morecostly and time consuming to buildas a bolt together unit. The weightincrease would have been especiallycritical.

    The fuselage frame was designedin such a way that two members goto every stress point, so that one canfail without a resulting catastrophe.It was built during one weekend andthe only power tools used were a drillpress and a Sears belt sander . . . plusthe welder's outfit, of course.

    For a landing gear Wayne stretchedSteve Wittman's 40 year old leafspring idea to it's ultimate limits not only does the tri-cycle set up usea leaf for the mains, but even the nosegear is mounted on a leaf that sticksstraight out to the front like spearat the ready. It's nothing more thana piece of 2024-T4 aluminum 30inches long, two inches wide and 1/2inch thick. This leaf is attached to thetop side of the front of the keel withone lousy bolt and a couple of springclamps. In keeping with Wayne's de-sire to make each component serve asmany purposes as is practical, therudder bar is even attached 11 1/2"out on the leaf, with a steering push-pull tube extending from the rudderbar out to the nose gear which isnothing more than a 6 inch aircraft

    52 JANUARY 1975

    tailwheel or a suitable, similarly sizedindustrial unit. You stand there andlook at that whole ridiculous rig andit's enough to make you sick to yourstomach . . . that you didn't think ofsomething so beautifully simple your-self!

    Wayne's prototype PDQ-2 isequipped with 5 inch go-kart wheelswith 3.40/3.00-5 two-ply tires. Ori-ginally, the plane was not equippedwith brakes, but they were addedfor its 1974 appearance at Oshkosh.If plans-built versions are to be flownoff pavement, the lightest kart or minibike brakes one can find are recom-mended. I'm sure more than one smartalec has already suggested to Waynethat he apply a layer of brake liningmaterial to the soles of his shoes sohe can simply drag his feet on roll out and that by dragging just one at atime, he can have the advantage ofdifferential braking. Deliver us,Lord, from our tormentors!

    One thing Wayne wanted to to dowith the PDQ-2 was incorporate somenew materials and building tech-niques in its construction, becausefrom the beginning he had not onlythe EAAer but also high school stu-dents in mind as builders. He wantedthe aircraft to be a teaching tool forschools and a first stepping stone forthose who would later go on to moresophisticated designs. After seeingKen Rand's foam and Dynel KR-1,the old PDQ-1 Fly Baby wings wereforgotten and the foam began to fly(ouch!).

    The PDQ-2 wing panels are fourspar affairs with plywood former ribsat the inboard and outboard ends,interspersed with 7 foam ribs (on theoriginal 16' 6" wing). The spars aresolid spruce boards consisting of a1/4" thick leading edge spar, a 1/2"main spar, a 1/2" rear spar and a 1/4"aileron spar. 3/4" thick 4' x 8' sheetsof ordinary 2 pound density Styro-foam or Urethane foam are bondedover the ribs. Numerous spanwisesaw-cuts are made about halfwaythrough the foam sheet on the bottomside to facilitate bending the sheet tothe contour of the rib without break-ing it. Solid strips of foam are bond-ed to the leading edge spar and arecut down to conform to the shape ofthe NASA 63 2A 615 airfoil.

    Wayne has a little different methodof applying his Dynel and epoxy thandoes Ken Rand, War Replica Aircraft,etc. Rather than just laying up theDynel over the foam and squeegeeingepoxy through the weave, Wayne firstbonds the edges, then shrinks thecloth taut with an iron. Thin resin issqueegeed into the cloth and lightlysanded after it has cured. A secondcoat containing micro spheres is thesqueegeed in, allowed to cure and

    then sanded. Any low spots are filledwith automotive spot putty, a finalsanding and priming is done and thecolor coat is applied. Throughout thePDQ-2 plans Wayne cautions buildersagain and again to watch the weightbuild up, and finishing the wing is oneof the really troublesome areas. Anamazing amount of weight is added tohomebuilts by many builders who tooenthusiastically strive for supersmooth finishes and on an ultra-ultra-light like the PDQ-2, you justcan't do this if you expect it to climbbeyond ground effect. Wayne's finishon the prototype looks great, provingyou don't have to overdo it.

    The PDQ-2 has full span aileronsand they are nothing more than a 1/4"thick spruce spar with an inboardplywood rib and ply gusset the rest,including the outboard tip rib, con-sists of shaped foam and Dynel.

    The rakishly swept fin and rudderand "T" mounted horizontal stabili-zer and elevator are built up just likethose on the KR-1, W.A.R. Fw. 190 and how every other foam and Dy-nel tail surface will undoubtedly bemade. The single-spar-and-foam sys-tem can't be improved upon.

    Once you get to the pilot's . . . well,I was going to say "cockpit", butsomehow that hoary old aviation termseems competely inappropriate whenit comes to identifying the area inwhich the pilot does his work in some-thing like a Breezy or, in this case, thePDQ-2. It's certainly anything but apit. Perhaps "pilot's precipice" wouldmore accurately describe the view onehas between his knees from a thou-sand feet in a PDQ-2.

    So, as I was saying, once you getto the pilot's precipice, things areboth spartan and clever. A small in-strument panel inclines forward be-tween the pilot's legs containing anairspeed indicator, altimeter, a littleWestach electric tach and the masterswitch. The rumor is unconfirmed thatthe PDQ crew gets around the com-pass requirement by wearing ahunter's wrist watch-type compasswhile flying. The edge of the precipiceover which the pilot dangles his legsout to the rudder bar is a wide traywhich doubles as a seat and the mountfor the fuel tank. Originally, fueltanks were built-up foam and Dynelcavities in each wing root, but theyproved to be leaky so an off-the-shelf6 gallon outboard motor tank hasbeen incorporated. A tiny motorcyclebattery is mounted just under thepilot's right knee.

    Anytime you passed the PDQ-2 atOshkosh there was a little semicircleof suppliants on their knees aroundthe seat of the aircraft apparentlyseeking wisdom of some sort. Theunique sidewinder stick/throttle was

  • the object of their supplication.Attached to the keel just behind thevertical mast, by a clever sort of gim-bal arrangement, the stick curves outand around the seat, falling right tohand as they say in sports car circles.The arcs inscribed by the stick as onemoves it up and down and from sideto side result in a rather odd feeling,but Lowell Farrand, the pilot who hasthe most time in the prototype, saysthis monkey motion is easy to adjustto. The stick's handgrip is a motor-cycle twist-type throttle, spring loadedto return the engine to idle if the gripis released . . . still another compon-ent serving a double function.

    And now, up the mast to the engine.Initial calculations indicated 90pounds was the absolute limit thatcould be tolerated on top of the mastand less would be highly desirable.A McCulloch could have been used,but Wayne was looking for some-thing smaller. The eventual choicewas a two cylinder, two cycle JLOof GOOcc capacity imported fromEurope by Rockwell. This particularengine had a singular advantage overothers considered in that having beendeveloped specifically for a groundeffects machine, it came equippedwith a propeller hub and the properthrust bearings no major modifi-cations were necessary for aircraftuse. The complete engine installation,including the propeller, weighs 70pounds. The JLO develops 45 hp at5500 rpm's (it is direct drive) with twocarburetors and 35 hp at 5000 rpm's.The only problem with the engine isthat as of Fly-In week at Oshkosh,Rockwell was no longer producing it which means that when stocks aresold, PDQ-2 builders will have tocome up with a suitable substitute.Wayne carved his own propeller, a44" x 17" unit that produces 175 to180 pounds of static thrust.

    Lowell Farrand (EAA 35370) ofGoshen, Indiana, a good friend ofWayne's and an experienced pilot,did the initial test flying. The firstflights were runs in ground effect upand down a local grass runway. Therequired test time (75 hours) was notflown off in time to allow flying atthe 1973 Oshkosh Fly-In, so the planewas a static display there. Upon re-turning home, more testing was done,with the first flights around the pat-tern being made during early fall.Lowell and Wayne were having somuch fun that, despite the lack of evena windshield up front, flying con-tinued on into the winter . . . and thisproved to be a fortunate thing.

    Initially, some aspects of the PDQ'sperformance were not up to expecta-tions, mainly rate of climb. This latterdeficiency was first laid to the engine despite Wayne's expertise with

    two cycle engines. However, tests re-vealed the JLO was turning up torated power, measured thrust seemedadequate and initial acceleration andlift-off were sprightly enough butit just didn't want to climb. Then onewintery day they found out why.

    Flying in a snow shower, Lowellhappened to look out across the wingand noticed that he could actually seethe pattern of the air flow over theairfoil just like in a smoke tunnelexcept here snowflakes were takingthe place of the smoke. The dark bluewing was a perfect background forviewing this phenomonon. Lowellvery quickly saw that his head andthe engine mast were forming a V-shaped wake that spread back andoutward over both wing panels veryeffectively spoiling the lift over agreat percentage of the wing. Fur-ther, increasing the angle of at-tack as when climbing cre-ated a larger and larger wake, ineffect reducing the effective aspectratio to almost nothing. No wonderit wouldn't climb. A little more ex-perimenting in the world's largest andleast expensive wind tunnel, as Waynelikes to say, resulted in some modi-fication to the airplane. First, the wingwas lengthened from 16 feet 6 inchesto 18 feet 6 inches, Cessna typewing tips were added and a couple offairly large plywood flow fences wereinstalled near the wing roots to con-

    tain the turbulent wake caused bythe pilot's head and the mast. Itworked like a charm now the littlebird would accelerate, rotate andclimb right out. Unfortunately, thesemodifications were significant enoughthat a new test time was assigned sothat, combined also with some downtime for re-license, once again thePDQ-2 was grounded (except for theirIndiana test area) when Oshkosh '74rolled around.

    The little bird was at Oshkosh,nevertheless, and Wayne had plansfor sale for $20.00 a set and was doinga brisk business particularly amongthe large Australian group that cameto Oshkosh. They consist of nine24" x 36" sheets and are quite com-plete. Especially helpful to thebuilder are the addresses of all thesources Wayne is aware of for ma-terials to build the airplaneJLO en-gines from Venture Aero-Marine,P.O. Box 5273, Akron, Ohio 44313and PDQ-2 materials kits from Air-craft Spruce and Specialty Co., Box424, Fullerton, California 92632 andRotor-Hawk, Inc., 9007 HendersonRd., Goodrich, Michigan 48438. Itwas good to see that the plans con-tained such items as control systemdetails, a complete bill of materialand even a layout showing how to cutribs, fin, rudder and aileron materialfrom 4' x 8' sheets of foam with theleast amount of wastage. A lot of

    (Continued on Next Page)

    (Photo by Jack Cox)A Bensen gyrocopter pilot would feel right at home here.

  • PDQ . . .(Continued from Preceding Page)building tips are also written righton the plans sheets.

    Although Oshkosh Conventiongoers have yet to see the PDQ-2 fly,it is a familiar sight to EAAers in theElkhart area, buzzing around like abig blue bumblebee. MinneapolisEAAers get to see the first plansbuilt PDQ-2 in action. This one be-longs to Gene Louismet (EAA 1490),8718 West River Rd., Minneapolis,Minnesota 55444, who at the time ofthe 1974 Oshkosh Fly-In was startinga second one. Hopefully, all of us willbe treated to perhaps a couple ofPDQ-2s flying at Oshkosh '75.

    Now, let's step back from the nutsand bolts examination of the PDQ-2and consider its position in the over-all sport aviation scheme of things.Ever since that day in March of1909 when Alberto Santos-Dumontsputtered aloft in his floppy-wingedlittle Demoiselle, tiny, low poweredairplanes have been an enduring fix-ture of the worldwide aviation scene.Super lightweights such as the Ital-ian Pegna-Bonmartini Rondine of1923 and the English Electric Wren,a star of the famous 1923 Lympnelightplane trials, actually flew on7 and 8 hp engines. During thebread line and apple stand daysof our Great Depression here inthe U. S., pilot's had to forego theirbeloved but gas-guzzling TravelAirs and Wacos for little put-putslike the 36 hp Aeronca C-3s and37 hp E-2 Cubs. Today, the EAAmovement is focusing worldwide at-tention on tiny, personal airplanes.

    It is possible, however, that we areseeing the beginnings of somethingnew with the PDQ-2. Most of the lowpowered aircraft of the past have beenborn of economic necessity exceptfor those homebuilders who are simp-ly fascinated with tiny airplanes.Most were actually substitutes for thebig, powerful aircraft owners reallywanted but couldn't afford. Today weare seeing a situation that is about180 out a guy who owns a Baronfor business, a Pitts for serious fool-ing around and when he sees a PDQ-2, thinks, "What a blast! I gottahave me one of those toys!". By wayof analogy, these people are justlike their neighbors who own a Con-tinental, a Porsche and a trail bikefor roaring into the woods to terrorizethe local wildlife.

    The PDQ-2, then, may be the har-binger of a "third level" type aircraft,a true recreational vehicle of the air.Most aircraft, and particularly mosthomebuilts, have always been usedalmost entirely for recreation butthey have been in what we might termthe "second level" or in the "sports

    54 JANUARY 1975

    car" category to use our analogyagain. The PDQ-2 is to aviation whatthe trail bike, snowmobile and all-terrain vehicles are to land transpor-tation.

    Of course, you can't so convenientlypigeon-hole airplanes anymore thanyou can land vehicles or people . . .especially people. There are thosewhose only vehicle is a sports car justas there are pilots whose only planeis a Pitts and by the same tokenthere will be many who by choice ornecessity will own only a PDQ-2. Atany rate, there is definitely a place inaviation for the properly designedsuper lightweight recreational vehicleof the air. There always has been.The only reason we have not alwayshad large numbers of this type of air-craft is the lack of a reliable, inex-pensive and, very significantly, light-weight engine (for weight and bal-ance considerations). With what weknow today about structures and newmaterials, think what our designerscould come up with given a 40 hp en-gine weighing about 50-55 poundsor so and small enough to fit in theproverbial bread box. Jim Bede hasproven there is a very large marketfor relatively low cost, high perfor-

    mance sport planes. Think of thepossibilities of an even less expen-sive trail bike or snowmobile of theair. Such aircraft could have a re-deeming social virtue, also, in the fuelsavings realized by pilots who coulddo their late evening fun flying intheir PDQ-2, or such, instead of intheir Bonanza.

    You can get in on the ground floorof this new phase of fun flying withWayne Ison's PDQ-2.

    PDQ-2 SPECIFICATIONSSpan . . . . . . . . . . . . . . . . . . . . . . . 18' 6"Chord . . . . . . . . . . . . . . . . . . . . . . . . 42'Airfoil . . . . . . . . . . . NASA 63 2A 615Wing Area . . . . . . . . . . . . 64.75 sq. ft.Wing Loading . . . . 6.5 lbs. per sq. ft.Span Loading . . . . . . . . . . . . 22.7 lbs.Empty Weight . . . . . . . . . . . . 218 lbs.Gross Weight . . . . . . . . . . . . . 421 lbs.Top Speed . . . . . . . . . . . . . . . . . 80 mphCruise . . . . . . . . . . . . . . . . . . . . 70 mphRate of Climb . . . . . . . . . . . 400 fpm +Stall Speed . . . . . . . . . . . . . . . . 46 mphEngine - Rockwell - JLO - LB-600-2

    Source: Wayne IsonNo. 7 Alpine LaneElkhart, Indiana 46514

    (Photo by Jack Cox)Lowell Farrand and the PDQ-2.

    Why is the PDQ-2 quick? The stark simplicity of thebasic fuselage is perhaps the most succinct answer just five pieces of aluminum, plus a few brackets andfittings.