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By Grover Mitchell(EAA 3686, Designee 57)55 3 E. Center StreetManches t e r , Connect icu t

AN ILL WIND BLOWS SOME GOOD

A D E C A D E A G O A smart- looking Stinson "Reliant" sa ton th e bank of th e Merr imac Rive r mo u nte d on a pairof Edo 4000 floats. A hurricane w as approach ing from th esouthwest, and before it w as over it had tumbled thisbeau t i f u l sh ip end ov er end d ow n the r iver and jus t a b o u tdemolished it . The engine an d some of the fuselage w asf o u n d , along w i t h one wing, a f t e r the hurr icane. Theremains of the floats were found below th e water levelsome t ime later by some f ishermen. N ot k no w i ng how toraise the remains, they drove 13 holes throu gh th e skin witha pickaxe to drain the water so tha t the floats could belifted aboard th e boat. The right float had the forward r ightside caved in almost to the cente r l ine ; muc h of the bot toman d side plat ing an d b u l k h e ad s were smashed beyondreclaiming, and the back w as broken just ahead of the step.Only th e last eight feet of the other f loat was ever fo u nd .W h e n I first encountered th e remains they were atJohn Marsten's Riverside Seaplane Base. John had rebu i l tmany a pair of floats, b ut since th e stretched bot tom skinsfo r these 1936 floats were no longer avai lable they sa t thereuntil I spotted them in December of 1964.

with a bride's ensemble there w as someth ing old, somethnew, someth ing bor rowed , an d something blue incorprated in it. I will sa y tha t to design an amphib ian to fly m i n i m um horsepower requires a very large gagglecompromises that have to be made to fly in fo rmat ion!FLIES!T he f irst test f l ights were made on A u g u s t 13, 19Ray Morin from the FAA office came out to the airport tpreceding day and gave it a very carefu l check-out . Rmade some valuable suggestions which were incorporaton the spot. I removed al l of the inspect ion plates , tturtle deck, and the engine cowling. I don't t h i n k there wa square inch of the ai rplane t h a t R ay d idn ' t l ook at f rotwo or three angles. (Ray is bu i ld ing a Midget Mustangneedless to say, th e w or km a n s h i p is perfect . ) R ay tooknu mbe r of pictures of it and completed the necessapaper wo r k . I spent th e rest of the day reassembl ing tsh ip and mak ing sure ev e ry th ing was ready t o go , wpart icular a t t ent ion to the special engine ins t rum entat iinstalled for the f irst f l ights to insure proper air pressure fengine cooling, oil and cylinder-head temp erature, etc.I had told th e many me mbe r s of our local Chapter w hha d he lped me to get i t to the airport and assembled, athose who had k ept t rack of i ts constru ct ion progress , thI w o u l d fl y early th e next morn ing as soon as a n y oshowed up to assist and to take pictures . R a o u l Messier wthere at 6:30 A.M. and we go t her f i red up and to the of the r u n w a y ab o u t 6:45A.M. I had planned to taxi it enough to check the way it hand led on the ground , and

The "Kitalina"Since m y high school days I had had the idea ofdesigning a small two-p lace amphib ian around just such af loat but I had never seen on e large enough to make th i s

possible. This one was 21 ft. 10 in. long an d 32 in. wide atth e step, an d weighed a b ou t 184 lbs. It seemed to holdsome promise of success. Since J o h n and I were pret ty goodswap artists, it wasn't long be fore th e r emains of the twofloats were on their w ay h o me on top of my four-doorsedan. I t w as a real eye-catcher on the way d o w n toManchester , Connect icut ; the f loat w as longe r t han th e car!I started work ing Saturdays repair ing the float inJanuary of 1965. N ew b u l k h e ad s were made an d ins tal led,and new deck parts were made and installed to s t ra igh tenout the deck l ine. New side skin w as instal led. I sa t an dlooked at th e large hole in the bot tom for a long t imebefore I f igured out how to p o u nd out compound-curvedsheets to make up for the unava i lab le fac tory-drawnbot tom plat ing i t originally had. Afte r I did a little moret rading, and came up wi th a sheet metal forming ai rh a m m e r , it really was not tha t diff icul t . T he a t t e m p tproved successful after a trial and error per iod . I t tookabout six m o n t h s to overhaul th e f loat. Dick Baj helped m ewi th i t abou t every Saturday , and be tween th e tw o of us wemanaged to come up w i t h solut ions to th e prob lems w eencounte red .Whi l e I w as repa i r i ng the f loa t , I w e n t t h r ough Janes'A ll T he W or ld ' s A i rc ra f t f rom 1909to 1964,and s tudiedevery f l y i n g boat ever b u i l t , and sent to the S m i t h s o n i a nIns t i t u t e for added i n format ion . I also obtained some bookswr i t ten i n E n g l a n d , the Uni t ed States, and G e r m a n y onf lying-boat design. I sketched up about 30 d i f f e r e n tdrawings of var ious configurat ions I could ad ap t to thef loat , and f inal ly fixed the design in S e p t e m b e r of 1965. A s12 APRIL 1971

everything seemed okay I figured I migh t as well fly it taxi it around al l day. Afte r I had taxied it abo u t 150 feve ry th ing seemed okay , so I opened the throt t le and Ra osaid it was airborne in about 800 ft. She was turn ing 230rp m static as the propeller pitch was a li t t le high for it, bthe hp curve on the C-85showed she was pu t t i n g out 75 hw h i c h w as enough for an in i t ia l f l ight . T he Sensenitwo-position propeller is a good one for an experimentship, as both th e high and low-pi t ch stops can be changed a few minutes . For the second f l ight I dropped the pi tcone degree and saw 2450 rpm on the tachometer . Befoth e third f l ight , a pi tch adjustment of one more degree pit r ight a t 2550 rpm, th e proper cruise rpm for thCont inen ta l C-85-FHJ engine . O ne m or e a d ju s t m e n t to tlow-pi tch stop brought this in to 2650 rpm dur ing t ak e -o fAfte r I added a precision fuel-pressure gauge to the primainjector p u m p , I w as ab le to adjus t th e m i x t u r e to gop t i m um m i x t u r e ratio dur ing f l ight b y using the m i x t ucontrol an d match i ng th e fuel pressure and rpm requirmen t s of the engin e . ( I chose th e fuel-injected e n g ibecause it m ad e possible a smaller frontal area for thengine nacelle.)O n the first f l ight , i t t r immed out hands-off a t 65 mpindica t ed , w hich was ab o u t it s best c l imb speed. I raised tleading edge of the stabilizer one-quar te r inch and thenflew at 85 mph indicated w i t h no t r im , w h i c h is its cruispeed at 24- inch mani fo ld pressure. Power-on stall wabout 50 mph ind ica ted ; touchdown was a t 45 mpi nd ica t ed .O ne o t h e r design tha t received a neg at ive react ion from a n y of my vis i tors during cons t ruc t ion concerned the "Ttail t h a t I incorpora ted . Most of them had read th e "T"-ts ta l l problems associated w ith the je t a i r l iners . I h

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reasoned that if I was to overcome th e nose-down charac-teristics on power application I had to have the stabilizer inth e propel le r blast. You can probab ly s ee tha t al t houghs t ru c tu ra l ly i t is a "T" tail , aerod yn amical ly it is nod i f fe re n t f rom th e usual a irp lane t h a t m o un t s the s tabi l izerclose to the propel ler t h r us t l ine , as a matter of fact , if Ihad moun te d it on the hull , I probably would have had thefl ight control diff icul t ies some t h o u g h t I would have wi thth e "T" tail .Th e landing gear and side f loat des ign, I bel ieve, isu n i q u e . For a wat er l and ing the side floats are electr ical lypositioned hor izontal ly f rom th e center hu l l . When landingth e center h u l l carr ies th e full l oad , th e side floats onlys tabil ize th e hu l l wh en i t i s at rest or m o v i n g slowly t h r o u g hth e water. They can be positioned electrically in anyposi t ion to give the desired stabi l i ty d epen d in g on the loadin th e center hu l l . For a take-of f f rom wate r they are upout of the way, they do not touch the water after thecenter hu l l is on the step.The side floats are also "wheel pants" for the wheels ,five inches of the 8.00x 4 tire projects from the bottom ofth e f loat . W h e n i t has been lowered to land on the g r o un d , Ihave exper i enced no dif f icu l ty on reasonably smootha i rpor t s wi th the c learance provid ed . T h e gear s t ru t s tha tex tend and retract to pos i t ion the f loats also have threeinches o f spring travel and hydrau l ic shock absorbers bui l tinto them bes ides th e re t rac t ion screw a nd n u t , w h i c h Isalvaged f rom a Cessna "Bamboo Bomber." This design usesth e f ron ta l area of the wheeled gear for the side f loats andth e w in g s can be folded or removed eas i ly, since no sidefloats are attached to them. A f te r t rying a number of geardrives , I f inally settled on the ones I insta l led . Thejackscrew is driven t h rough a two- to- three cha in r ed uct i onfrom a pair of 20:1 gear boxes. The gear boxes are drivenby a 5000 rp m d ouble shaf t electr ic motor t h rough flexibleshaf ts . The gear boxes and motor came from a 1951Plymouth convertible and were used to operate theconver t ible top. The act ion is p owerf u l en ough to jack th em ain h u l l off of the g r o u n d , if you place one of the wheelson a mechanic's creeper or other wheeled platform that willle t th e wheels come toge the r w i t h o u t to o m u c h f r i c t ion .Th e c o m b i n a t i o n t a i lwhee l and the water rudder is alsoelect r ical ly re t rac tab l e , actuated by a Culver V m ain-gea rre t rac t ion motor and gear box. Some other f ly ing boatdesign "secrets" I discovered in my s tudy of most of thesh ip s of th i s t y p e w e r e :1. Center-of-grav i ty locations in reference to the plan-in g step. A m e r i c a n pract ice was to place i t a t abouto n e - t h i r d of the w i d t h of the step, ahead of thestep. British pract ice places th e center of gravi ty atth e step. I managed to find pi lots who had f lownboth t y pe s in World War II , and apparent ly therewere a few unstable moments on the British shipsw h i l e th e sh ip w as ge t t ing on the step, especial ly ina c rosswin d .2. The m ain-whee l tread in a tail-dragger should toucht he g roun d , w h e n th e sh ip i s in the three-poin t

posi t ion , at a po i n t in tersect ing a l ine t h a t goest h r o u g h th e center of gravity and is inclined 17degrees f o rward f rom a vert ical dropped t h r o u g hth e cen te r of g ra v i ty . This is t rue of any s h i p ,a m p h i b i o u s o r not .3 . Tail -dragger a m p h i b i a n s can beach t hemselves byt a x i in g out of the water better t han t r icycle-geara m p h i b i a n s or the tw in - f l oa t wheel gear wi th th esma l l nose wheels.4. Most smal l a m p h i b i a n s b u i l t to date have had tooshort a boat h u l l ahead of the cen te r of grav i ty . Thisl imi ts them to low wave and swell conditions forw a t e r t a k e - o f f s .5. Cente r of la teral-area loca t i on s i s impor t an t i na m ph i b i a n s because of the hull projection ahead of

(Photo by Hooks Johnson)The "Kitalina" d o e s f ly, r e g a r d l e s sof what skeptics might have thought.

(Photo by Hooks Johnson)The Mitchell "Kitalina/' N-5577, offers a strange appear-ance on the ground, particularly with it s wheels mountedinside the floats. The exhaust is carried up over the wingand engine by f lexible tubes. The wing itself appears tohave originated in a Luscombe.

SPORT AVIATION 13

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THE "KITALINA" . . .(Continued from Preceding Page)th e cen t e r o f g r a v i t y . B y s w e e p i n g the f in andr u d d e r b a c k , I ga ined a l o n g e r m o m e n t a rm, th eh i g h t u r t l e d e c k i s also necessary to m o v e th e ce n t e ro f l a t e r a l area b a c k . T h e cent e r o f l a t e r a l area isl o c a t e d a t a b o u t 3 8 p e r ce n t o f t he f in and r u d d e rm o m e n t , back o f t he ce n t e r o f g r a v i t y .6 . F l y i n g b o a t s a nd a m p h i b i a n s a r e t h r u s t cr i t ica lw h i l e g e t t i n g on th e s t e p . I f you h a v e t h r u s t e no u g hto ge t i t on the s t ep f o r a w a t e r t a k e - o f f , y o u wi l lh a v e p l e n t y o f t h r u s t to f ly i t .A l t h o u g h t h e s t r u t s t h a t h o l d t h e e n g i n e a nd w i n g u pa r e des igned t o t ake up t o 125-hp engines , I bel ieve I geta l m o s t a s m u c h t h r u s t f r om th e t w o - p o s i t i o n p rope l l e r ande n g i n e c o m b i n a t i o n ( C - 8 5 - F H J ) a s I w o u l d out o f a 125-hpeng ine w i t h a f i x e d - p i t c h prope l l e r . (No va r i ab le prope l lersa re a v a i l a b l e fo r the 125-hp e n g i n e s to my k n o w l e d g ee x c e p t th e A e r o m a t i c s . )DESIGN CONSIDERATIONS

I f l ew a p o p u l a r p u s h e r a m p h i b i a n i n 1964, and thet e nd e nc y t o d r o p i t s nose o n s u d d e n a p p l i c a t i o n o f p o w e rwas d i sconce r t ing t o s ay t he l e a s t , e spec i a l l y on a missedapproach on a w a t e r l a nd i ng . I had a s a goa l t he e l i m i na t i o no f t h i s t r a i t , w h i c h i s very c o m m o n f o r h i g h - t h r u s t - l i n esh ip s . Because o f th i s I b u i l t in s om e u p - t h r u s t t o t h eprope l l e r sha f t in r e l a t i on to the wing a ng l e of inc idenceand s t ab i l i z e r s e t t i ng . I hit a w o r k a b l e com p r om i s e a s th e" K i t a l i n a " a cce le r a te s f o rward w i t h th e s u dde n a p p l i c a t i o no f power a nd t h e n starts to c l imb a t a norma l rate for thepower se t t ing . I w i l l d i scuss t h i s aspec t o f a m p h i b i a n des ignw i t h a n y m e m b e r s w h o a r e in t e re s t ed i n t h i s s o lu t i on . Ichose th e tractor prope l l e r main ly because w i t h a n eng inem o u n t e d h i g h and in back o f th e ce n t e r o f g r av i t y , a s i nmost p u s h e r i n s t a l l a t i o n s , th e e n g i n e w e i g h t t e n d s t o l o w e rth e ta i l in a spin , w h i c h can lead to a f l a t spin that may behard to ge t ou t o f . W i t h th e t r a c t o r e n g i n e and prope l l e rm o u n t e d h i g h and ahead o f t he ce n t e r o f g r a v i t y , i t causesthe sh ip to ra ise the t a i l in a spin a n d t h u s assist spinr e c o v e r y . I f y o u w o u l d l i k e to p r o v e t h i s t o y o u r s e l f , m a k ea sma l l m o d e l a i r p l a n e w i t h w e i g h t s t h a t s i m u l a t e e n g i n eweigh t in t he two p os i t i on s , h a n g i t f r om i ts center o fg r a v i t y , a nd g i ve it a s p i n .AFTERTHOUGHTS

I com p l e t e d th e " K i t a l i n a " a f t e r s p e nd i ng 5500 hou r sn i g h t s a n d w e e k e n d s i n m y s h o p . O f t h i s t i m e , a b o u t 4 0pe rcent o f i t was spen t d o i n g c o ns t r u c t i o n w o r k , t e np e r ce n t f o r j u s t s i t t i ng a nd l o o k i n g a t a p rob lem andt u r n i n g o v e r v a r i o u s w a y s o f so lving i t , and a g ood 50pe rcent w a s s p e n t t a l k i n g t o v i s i t o rs who were in t e r es t ed inth e pro j ec t . T h e mo s t v i s i t o r s in any one n i g h t w a s 3 5p e o p l e ! O ne w e e k o v e r 10 0 i n d i v i d u a l s s t o ppe d in, ing r ou p s o f f r om two t o six.In t im e , e v e r y o n e w i t h i n 200mil es who was in t e re s t ed had se en i t , and the v o l u m ed r o p p e d d o w n c o ns i d e r a b l y , b u t t h e y s t i l l came b a c k f r omt im e to t i m e to check up on t he progress. In the pas t y e a r awho le new gene ra t i on o f interested people ha v e stopped in .Out o f e ach g r ou p t h e r e w a s gener a l l y o ne w h o h a dsome spec i f ic q u e s t i o n a b o u t t h e E A A o r a i r p l a n e cons t r uc-tion. Some w o u l d j u s t w a n t to t a l k . Some w a n t e d to h e l pm a k e some pa r t s o r b u c k some r ive t s w h i l e t h e y t a l k eda b o u t t h e i r a v i a t i o n in t e r es t s . M a n y b r o u g h t t h e i r w i v e s o rgirl f r iends t o conv ince t h e m that i f I could do i t perhapst h e y c o u l d b u i l d one. M a n y o f t he v i s i t o r s w e r e q u i t eskep t i ca l a b o u t t h e w h o l e idea b u t l a t e r t h e y w o u l d b r ingsomeone a r o u nd just to prove to t h e m that w h a t th e y toldt h e m a b o u t "that guy" in M a nc h e s t e r w h o i s des i gn ing a ndb u i l d i n g h i s o w n a m p h i b i a n w a s rea l ly t r u e . A t v a r i o u stimes I have been act ive in b o a t i ng , target shooting,14 APRIL 1971

(Photo by Ray MorThe front c o c k p i t is uncovered here, and details of tlanding-gear/float arrangement are quite visible. Tfloats c ome up to a horizontal position for water operatiom o t o r c y c l i ng , c h u r c h w o r k , etc.,bu t I neve r t a lked wi t h m a n y people be fo re a b o u t a c o m m o n in t e r es t a s w h i l e t" K i t a l i n a " w a s u nd e r c o ns t r u c t i o n . O f cour s e , th e i db e h i nd b u i l d i n g i t in the f i rs t place was to get a l i texe rc i se and change o f pace f r om a n o f f i ce jo b w o r k i n gmy f u l l - t i m e o c c u p a t i o n in i ndus t r i a l t r a i n in g a c t i v i t i e se n j o y e d i t all, a l t h o u g h for a w h i l e w e s e t F r i d a y n ias ide eve ry w e e k fo r "open h o u s e . " M a n y F r i d a y n i g hwere t o t a l l y t a k e n u p w i t h v i s i t o r s and gue s t s .O ne i n d i v i d u a l came in and l o o k e d i t o v e r vecarefu l ly and co n f i d e d in me t h a t i t was a n ice p iecew o r k m a n s h i p b u t t h a t i t w o u l d n e v e r f l y . W h e n I a s k e d hw h y , h e said i t was too heavy to f l y , so I a sked h im w h a tt h o u g h t th e bare h u l l weighed and he s a id a t leas t 800 Ibsa s k e d h i s t e n - y e a r o l d b o y w h o w a s w i t h h im w h a tt h o u g h t t h e h u l l w e i g h e d and he gue ssed a b o u t 16 0 Ibs .w as closer t h a n h is f a t he r i t we ighs 184 Ibs.S h o u l d y o u a t t e m p t to b u i l d a n a i r p l a n e ? I t a l l d e p e no n w h a t y o u rea l ly w a n t . I f you rea l ly w a n t to f l y , y o u hbetter b u y a n a i rp l ane you can a f fo rd and f ly i t . I f lew mT e mc o " S w i f t " fo r fou r y e a r s (m y 12th a i r p l a n e ) . H a l f wt h r o u g h th e " K i t a l i n a " p r o j e c t I so ld i t a s I had on ly f l o w29 h o u r s t h a t y e a r in i t and 84 h o u r s in o t h e r p e o p la i rp l anes . In J u l y , 1969I p icked up in p a r t n e r s h i p w i t h EG r e a n e y ( p r e s i d e n t o f C h a p t e r 166) a 1951 "Pacer"cou ld b r u s h up on my f l y i n g ski l l s be fo re I t e s t - f l ew t" K i t a l i n a . " B y J a n u a r y we had 7 5 hou rs on i t and we ht o pu t new f a b r i c on th e f us e l a ge , but i t i s f l y i n g n ow.If y o u l i k e to b u i l d t h i n g s , y o u wil l p r o b a b l y c o m p la n a i rp l ane pro jec t . I don't k n o w of any "easy" w a y b u i l d i n g a good a i r p l a n e y o u w o u l d b e p r o u d t o f l y . I t t a ka l o t o f t h o u g h t , y o u l e a rn a lo t of ski l l s , a nd y o u d o a lo f w o r k . B u t , i t seems more l i k e f u n w h e n y o u l o ok backi t and no t l i ke w o r k a t all.M y n e x t p ro jec t i s a l r eady on th e d r a w i n g b o a r d ! Aboy I m a de m ode l a i rp l anes , g i g s , b i cyc l es , etc., ou t o f spaparts. Af te r I go t m a r r i e d I b u i l t m y s e l f a t w o - c a r ga r ageh o u s e , a nu m b e r o f boats, n e x t 13,000 sq. f t . o f i n d u s t rb u i l d i n g s ( so I c o u l d r en t t h e m ou t and t h u s a f f o r d to f lA ll were p a r t - t i m e projects . S o me t o o k y e a r s t o com p l eI f y o u have s i m i l a r in t e r es t s a n d e n j o y b u i l d i n g t h i n g s ,you r ea l l y wan t t o b u i l d and f l y y o u r o w n a i r p l a n e , y o u cdo i t . H i g h m o t i v a t i o n c a n ov e r com e a ny l ack o f s k i l l s aknowledge . I h ave run two w e l d i n g g r o u p s f o r C h a p t e r 16w e h a v e t r a i n e d 3 0 m e m b e r s in the sk i l l s a nd k n o w l e d g eweld ing a i rc ra f t s t ruc ture s .T h e " K i t a l i n a " na m e came f r om m y a d m i r a t i o n f o r tPB Y "Catalina" p a t r o l , se a rch and rescue a m p h i b i a n sW o rl d W a r I I f ame . I couldn't b u i l d o ne that big, but I db u i l d a d i m i n u t i v e one so the n a m e " K i t a l i n a . "W i l l p l a n s be m a d e a v a i l a b l e ? I don't k n o w yetenough people a re interested, m a y b e s om e t h in g can w o r k e d out.I w o u l d no t h a v e th e t i m e to t e n d t o i t , bs o me o ne m a y wis h to t ake i t over . T h e m a n u f a c t u r ir igh t s a re ava i l ab l e if anyone is interested.