Spratt Controlwing

Очень интересный гидросамолёт, управление - подвижным крылом.



Я никак не связан с нынешним владельцем чертежей (Bill Wolfe) коммерческими интересами, но о покупке чертежей с ним переписывался. Он отправляет документацию со страховкой, принимает в оплату вестерн и манигрэм  :D, поэтому цена материалов будет несколько больше, но в пределах разумного.

Билл позволил разместить здесь историю этого самолёта в его изложении.

/me



I first met George G. Spratt in 1969 when fellow engineers at Boeing Philadelphia invited me to join them on the Chesapeake Bay to see the Spratt Controlwing. At that time I had never heard of it.

     My first view of the aircraft was from a small dinghy George brought to shore to take visitors out to his home-built 55 foot, arc welded steel personal aircraft carrier, anchored over a  large shallow spot in the middle of the Bay to demonstrate his prototype Controlwing flying boat N910Z.

    This aircraft was flown by over 100 pilots in the 60s and 70s, including me, for several hundred accident free hours. It was the most often seen model shown in many magazines. Most new pilots loved it but old timers did not care for it much since no stunts were possible with such a stable aircraft.

    I built my first 85 HP Mercury powered, all wood Spratt model 107 flying boat in the late 90s. In 2000 my flight medical expired just as I started flight testing. I only made a few short hops before selling it as no other test pilot was available.

   The Tampa buyer claimed he was going to build kits but only used the hull as a claimed 75 mph runabout. It was re-sold it  to a Norfolk man who never actually flew it. If I could swing it, I would buy it back and donate it to the smithsonian.

   Last year I started another Spratt flying boat incorporating some hull mods and planned to use a 120 HP, liquid cooled VW but at age 83 I ran out of steam and money before I was almost ready to install the engine. A friend in Orlando is completing it and hopes to have it ready for the very first public demonstrations ever made for a Controlwing by winter.

   He and Florida friends are seriously considering a Controlwing kit development next.


The Spratt and Controlwing Flying Boat History

The Spratt Controlwing flying boat is a favorite subject of mine ever since I first saw and flew the 60 HP Mercury powered prototype N910Z in 1969. I built my first 85 HP Mercury powered Controlwing flying boat N107GW in the 90s. I have been a strong advocate to keep this kinder, gentler and safer aircraft design.

    I was building a second Controlwing flying boat using a 120 HP liquid cooled VW engine which is now being completed by friends in Florida. This particular aircraft is intended to be shown at major air shows for the aviation community and the general public to see one for the very first time. After public demonstrations the development of a Controlwing flying boat kit is expected to get underway.
     
    Surprisingly the name Spratt and the Controlwing is still not very widely known to people both inside and outside of the aviation community. Spratt’s 200#, Evinrude powered ultralight roadable Controlwing was shown in the August 1936 Popular Science magazine and the Spratt/Stout flying Automobile in the June 1945 Popular Mechanics, “The Brain Behind the Wrights” in the January 1962 Climax Magazine, the Spratt Controlwing flying boat was the cover article for both the June 1962 Popular Mechanics magazine and the April 1970 Science and Mechanics magazine and also in the September 1969 AOPA Pilot magazine. The Experimental Aircraft Association’s 'Sport Aviation' magazine had Controlwing articles in the July 1972, December 1973, June and July 1974, May 1976 and May 1980 and in the April 2000 Experimenter magazine. The Smithsonian’s December ‘94/ January ’95 Air and Space magazine had a Controlwing article and my aircraft was shown several times in later EAA publications.
A film was recently prepared for the Smithsonian Network covering early aviation and experimental aircraft including Spratt Controlwing aircraft.

    I knew and often visited George G. Spratt as a personal friend for 29 years. He was a visionary aeronautical engineer, inventor and a true gentleman.

    There were two Spratt Controlwing flying boats flying in the Chesapeake Bay area during the mid 60's to mid 70's accumulating hundreds of accident free hours, and soloed by over 100 pilots who only had to ask. The sole Spratt Controlwing Subaru powered land plane prototype is now in the Mid Atlantic Air Museum at Reading, PA. A Rotax powered ultralight  with a single rubber float was built but never fully developed.

     My Spratt Controlwing flying boat N107GW was only the third plans-built flying boat to be completed and flown up to now as far as the late George G. Spratt and I knew. All three were built primarily of wood rather than the all composite construction like the prototype N910Z. Of the other two, both using VW engines, one was lost in a water collision and the other one may be deteriorating in Florida. N107GW is the only Spratt Controlwing aircraft in the current FAA registry. I have been told that Controlwings have been seen in Canada.

     Dr. George A. Spratt, a 1885 medical school graduate, developed a serious heart condition preventing him from practicing medicine so he took an interest in aerodynamics and became a close friend of Octave Chanute. They both realized that since liftoff was easily attained, they concentrated their developments and experiments in the very important and more difficult area of stability and control. Spratt made extensive observations of the wings of birds and bees and insects to develope his early elementary understanding of nature's subtle solutions to the stability and control of flying creatures which is now commonly known to the public due to high speed photography.

    Chanute and Spratt were intrigued by the efforts of Wilbur and Orville Wright and offered their free assistance. Dr. Spratt visited them at Kitty Hawk frequently and eventually became their primary aeronautical consultant. After introducing them to his own elaborate wind tunnel that measured both lift and drag, they were later able to copy his wind tunnel and use it for some of their experiments including a very effective propeller development.

    The Wrights have been given much undue credit as single-handedly developing the first successful powered aircraft, but Spratt's volunteer technical assistance and design changes played a significant part in their ultimate success. He is rarely mentioned in history books and then only as a casual visiting fisherman. A Wright employee built their engines from scratch, they were fortunate to have a supportive family, an established business from which they could take time off, had the use of that facility to develop their aircraft and neither one ever married. These two totally dedicated brothers had little social life to speak of.

    Chanute and Spratt did not agree with the Wright's complicated three control approach and suggested simpler Controlwing design features which they rejected but Spratt helped them do it their way anyway.  Spratt and Chanute later delivered a large Controlwing glider of their own design to Kitty Hawk. It was successfully flown and offered it to the Wright's for continued testing but they abandoned it to the weather.

   Had they continued testing it, aviation history may have been quite different and tens of thousands of lives would have been saved. They believed elaborate pilot training was better than having the built-in stability and safety features found in the Controlwing designs.

    Wilbur and Orville were more than willing to accept Spratt's volunteer technical assistance but were not willing to share their celebrity or any potential financial gains. They rarely acknowledged him or his important design changes which helped lead to their ultimate success, however they never hesitated to call upon him as an expert witness for many patent suites years later. It took fourteen years for Dr. Spratt to get his own Controlwing related patents because the patent office officials consistently could not understand such a different concept from other existing aircraft. See the web site www.georgespratt.org  for more of the interesting Spratt/Wright connection and other information.

    Dr. Spratt, and with his son the late George G. Spratt, built twenty different gliders, seaplanes and land planes. Each one incorporated a Controlwing in some fashion, including a successful flying automobile developed in conjunction with Bill Stout which was seriously considered for production by Convair and a smaller land plane developed for Bendix but not pursued as management elected not to compete with their customers.

    In 1936 George G. Spratt was flying his 200 # Evinrude powered, roadable ultralight Controlwing!  I suspect many people believe ultralights are a new and modern idea. To view this aircraft in operation, see “Aeronautical Oddities”, an Experimental Aircraft Association video of older and unusual flying machines.

 
 
    My Controlwing flying boat N107GW was built using George G. Spratt's 1973 plans with many personal changes incorporated and marked on the plans. I used an 85 HP Mercury marine outboard powerhead, modified per Spratt's instructions. Wooden construction was used throughout, not the all composite construction of the early prototype N910Z which weighed about 500 lbs. Mine and one of two other known all wood plans-built aircraft flown weighed about 250 pounds more. My aircraft may be seen in the September and October 1998 Sport Aviation magazines, the April 2000 Experimenter, EAA’s Aerocrafter plans book and the web site www.georgespratt.org

                I offer a Controlwing flying boat plans package including 33 of Spratt's drawings, 80 pages of construction and general miscellaneous information plus a 35 minute video showing Controlwing prototype flying boat operations, the Controlwing prototype land plane operation and much taxi testing of my aircraft and the takeoff of my last short flight before my medical expired. The plans package is $115.00 US, post paid. For foreign air mail delivery add $25.00.

     After I first saw and had the opportunity to fly the 60 HP Mercury powered Spratt Controlwing flying boat prototype N910Z, I immediately fell in love with it and decided this was the only aircraft I would ever care to own. After dreaming about it a long time I finally built my first one in the late 90s.

     Spratt often demonstrated his Controlwing flying boats while operating from his personal aircraft carrier; a home-built, 55 foot, arc welded steel, diesel powered utility vessel conveniently anchored over shallow sandbars in the middle of Chesapeake Bay.

    The FAA Experimental Aircraft license is primarily for the builder's education and recreation. I got a lot of the educational part but very little of the recreational part as my medical expired just as flight testing started. With no other experienced Controlwing pilot available to continue the flight test program, I sold the aircraft to a man in Tampa who claimed he would build kits but only used the hull as a 75 mph runabout. He re-sold it to a fellow in Norfolk who trailered the Controlwing to Kitty Hawk during the 100th Anniversary of Flight but parking or display space in the vicinity or even at the local airport was denied by local, state and Federal authorities.

    Should an entrepreneur wish to develop a Controlwing kit, I would be more than happy to assist technically. Many knowledgeable people in the aviation community believe that such a kit would be well received and especially attractive for new and student pilots, senior citizens and  homebuilders due to their lower cost,  simplicity, extreme operational safety and comfort. .

    Even though the original breakthrough for such a safe aircraft was evident in the early 60's, apparently investors and other parties were afraid of liability for something so vastly different from existing aircraft design concepts or they may not have fully understood the unusual aerodynamics of the Spratt Controlwing. Many aviation people still do not understand or believe this concept. When advanced military aircraft proposals were solicited during WW II,  Dr. Spratt submitted Controlwing aircraft designs which were looked upon very favorably but would be seriously considered only after they were put into actual production.

    Of more than 100 pilots who flew a Spratt Controlwing flying boat prototype simply by asking,  the low time and student pilots loved it but the more experienced pilots did not care much for it because there was so little for them to do and no stunts were possible with such a docile aircraft.

    I taxied my Controlwing flying boat a lot but flew it only on very brief test hops as the FAA flight test plan got underway. Testing dragged out a very long time as numerous bugs such as engine installation, carburetors, vee belt tension adjustment, exhaust system, cooling system, control linkage revisions and wing panel balance were ironed out including my lack of experience and with no other knowledgable technical assistance available. There were no defining instructions from Spratt regarding control rigging, wing panel balance and the desired pilot pitch control inputs.  This important information was gained only from experience.

    All the pictures and video I have were taken by casual bystanders. Unfortunately no professional photography was done at all and no in-flight photographs were ever taken.

    My last brief test flight on October 4, 2000 is seen in a video showing the takeoff at 50 mph to about 50 or 75 feet before outdistancing the chase boat. There were not enough brief liftoffs to record any meaningful data during our frequent trips to Beaver Lake, most to tinker with the engine, carbutators or vee belt tensioner.

    Nearly five years of labor and test time went into this project, my first attempt at building an aircraft. I was a Senior Aerospace Design Engineer for thirty six years but that helped very little with this project requiring woodworking, metalwork, fiberglass, machining, welding, engine and instrument installation skills plus flight testing..

    A Controlwing kit would vastly simplify and shorten construction time for the home builder. Freinds now completing my second Controlwing flying boat are seriously considering such a project.


                   ---   Spratt Controlwing Flying Boat Operations   ---


    In flight, both hinged parasol wing panels collectively and aerodynamically maintain a relatively constant angle of attack with a variable angle of incidence in reference to the hull. The NACA 23112 reflex airfoil was selected due to its favorable aerodynamic pitch response and small excursion of the lift vector. The wing panels are moved differentially to provide a very gentle bank and turn. The wide fixed vee shaped tail has no movable surfaces. It only guides the aircraft like feathers on an arrow and acts as a venturi to providestail lift at cruise and higher power settings.

     Flight controls consisted of a throttle, steering wheel and an auxiliary pitch stick. Since the inherently stable Controlwing flying boat has no conventional ailerons, rudder or elevator, pilot control coordination is not required like in other aircraft. Conventional aircraft which can stall, spin and dive use those movable surfaces to direct an aircraft in pitch, roll, yaw and maneuvers about the CG.

   The steering wheel of the Controlwing only controls the differential angle between wing panels to provide a gentle bank and turn in the air and move the very effective kick-up, retractable water rudder. There is no feedback or cross talk between the pilot's pitch and roll inputs or outputs with this very simplistic control system and the auxiliary pitch stick is only used when the pilot desires to shorten a takeoff, move above or below an existing stable flight path or glide path, or to flare for a smoother landing.

    The throttle, conveniently attached to the auxiliary pitch stick which is mounted low like in a helicopter, is the primary vertical flight control. Hands-off takeoffs and landings may be made solely by increasing or decreasing power. With higher power settings the flying boat hull will assume a relatively level attitude for takeoff and cruise flight. When power is reduced to idle, tail lift is reduced and the hull will assume a nose high attitude essential for a safe water landing and the angle of incidence of the wing panels will automatically be reduced to accommodate the stable glide path.

    No air rudder is needed for the flying boat since the small angular difference between the wing panels does not create adverse yaw. Fast, sharp turns can be made on the water due to the low center of gravity, wide hull and the lack of wing tip floats to trip over. A Controlwing flying boat banks into the turns like any motorboat and can pivot about a wingtip touching the water and it is relatively crosswind tolerant.

    With a very minimum of flight training, a novice could easily and safely fly a Controlwing flying boat. Any pilot could receive adequate flight instructions by telephone. These kinder, gentler and safer aircraft have no inherent spin or dive capability and when the stick remains unrestrained during flight through turbulence, the occupants will sense only about one quarter of the normal gust loads.

  The Controlwing flying boat is the safest, simplest, easiest to fly and most comfortable aircraft ever developed!  Fly it yourself and you will believe it.

    George Spratt often asked, "Did you ever see a fixed wing bird"? To that I add, "Did you ever see a bird with a rudder...or a low wing?"

 Separate photos show my first all wood Controlwing flying boat N107GW.


 Bill Wolfe  1520 W. Ash St., Rogers, AR 72758-5014   1(479) 621-5822

 EAA # 5716   SAA # 1431    1(479) 621-5822   billwolfe1@sbcglobal.net
 Northwest Arkansas EAA Chapter 732

 You may copy and re-distribute this information to any interested parties.
 

samodelkin_33rus

Я люблю этот Форум!
А он хоть летает? И как если летает ?  А то я что то нигде фоток в полете не увидил, ни здесь ни на его сайте.
 
Пришли чертежи доставкой "в руки" через EMS гарантпост почта России. Тубус дошёл через две недели, пакет с описанием и видео- через три. Чертежи очень хорошего качества и подробные. Аппарат со складными крыльями (это моя слабость). Двигатель- конверсия подвесного Mercury 850 (85 л.с.).

/me
 
Несмотря на то, что изображение на видеокассете оставляет желать лучшего, некоторые скриншоты удалось сделать. Похоже, что это переписанные на кассету 8-миллиметровые киноплёнки, которые не одно десятилетие показывали на семейных пати.

Изображение малого формата, чтобы не видно было зерна, но сюжет должен быть ясен.

Spratt Controlwing на корме небольшой двухмачтовой яхты. Чесапикский залив, 1969-1973 г.г.

/me
 

Вложения

Швартовка.

Интересного на кассете ещё много, но надо смотреть последовательность кадров как сюжет, чтобы сгладить разумом дефекты плёнки.  ;)

/me
 

Вложения

Живя тут 29лет и немного знаком с нашей западной самопальной авицыей........если их не летают несколько сотен штук..значить есть причина..что между прочим и касается и Беркута он очень сложен в построение, минимум 2500 часов на постройку....

Насчёт этого тарантаса....вы должны сами раследовать почему он непопулярен....как видно он лёгок в постройке...тогда что остаеться? ;) Учитесь на ошибках других...а не насвоих!
 
Вверх