Talk:CTA Convertiplano

Correct history for the CTA Heliconair HC-I, Ib and II Convertiplano
Brazil’s first foray into jet aircraft started in about 1950 with the arrival of Dr. Heinrich Focke, formerly of Focke-Wulf Flugzeugbau AG in Germany, and his founding of the Centro Técnico Aeroespacial (CTA) in Brazil.

With Professor Focke's background well established in lifting bodies, such as auto-gyros like the German-built, licensed version of the La Cierva C-19 and C-30, Dr. Focke also had several Short Take Off and Landing (STOL) and Vertical Take Off and Landing (STOL) projects in Germany during the Second World War. These included helicopters such as the Fw-61 then the huge Focke-Achgelis series Fa-223 Drache "Dragon" and VTOL aircraft such as the Fa-224, Fa-266, Fa-269, Fa-283, Fa-284 and Fa-336. He also designed a flying kite, the Fa-330 and converted an Fw-190 piston-engined fighter into a jet aircraft using his own designed Fw-T1 centrifugal turbojet. His German designs culminated with the Fw-Rochen "Sting Ray" which was a VTOL aircraft powered by the same Fw-T1 driving two counter-rotating propeller blades in the center of the aircraft. The war ended before this design advanced beyond the wind-tunnel models and a 2/3 scale test aircraft.

Naturally, by the time he reached Brazil, Dr. Focke’s focus continued to be on VTOL aircraft. He found a more-than-willing government in Brazil under the leadership of General Eurico Gaspar Dutra, the former commander of the Brazilian Expeditionary Force, which fought in Europe during the Second World War on the Allied side. Coincidentally, this was the same period that Dr. Kurt Tank, also from Focke-Wulf, was helping Argentina build and fly the Instituto Aeronautica I.Ae.33 Pulqui II "Arrow," under General Peron and Willie Messerschmitt was working in Spain on the Hispano Aviacion Ha-200 Saeta "Thunderbolt," for General Franco.

As resources for such a project were meager at best, Dr. Focke decided to utilize a Supermarine Spitfire Mk. XIV airframe sent to Brazil as a sales demonstration aircraft by Great Britain. Using the wings and airframe, he modified it to accept the Armstrong Siddeley Double Mamba gas-turbine engine. For VTOL he attached four small wings driving counter-rotating propellers on each side. One set was forward of the cockpit with the second set just behind the wings. The tail-planes were also raised to the top of the tail fin to insure stability and steer clear of the exhaust.

At that time the United Kingdom decided to stop supplying the Double Mamba to Brazil. With a Labor government in power, it may have been due to Brazil’s right-of-center leadership by the Social Democratic Party-PSD. (Yet during this same period the United Kingdom did supply Argentina, a fascist state, and the Soviet Union, a socialist state, with the Rolls-Royce Nene II.) With this development Dr. Tank hurriedly redesigned the airframe to accept a Wright R-3350-DA3 Turbo Compound 18-cylinder supercharged radial engine taken from a Lockheed Super Constellation, just behind the cockpit. Of course with this revision the passenger/payload compartment was removed and the airframe proved too heavy. This was mainly because the original jet engine was about 700 lbs. or 320 kgs. and the piston engine over 2,670 lbs. or 1,212 kgs.

Finally arrangements were made with the U.S.A. to obtain the General Electric G.E. T-58 gas-turbine jet engine. Since this engine weighed only 250 lbs. or 110 kgs., the original layout, with the passenger compartment, was restored with a new designation of HC-II. Four engines were attached, one for each turboprop. Combined engine weight was 1,000 lbs. or about 450 kgs., less than 50% of the piston engine and only 30% more than the original jet engine.

Upon completion the Heliconair HC-II Convertiplano was capable of speeds up to 500 km/h as well as almost direct vertical takeoffs and landings. After testing was completed Dr. Focke returned to Germany and the aircraft was put into storage and virtually forgotten.

Dimensions:

Wingspan: 37’6" (11.42m)

Length: 35’3" (10.74m)

Height: 15’0" (4.57m)

Weight: Unknown

Performance Data:

Top Speed: 310 mph (500 km/h)

Range: Unknown

Thrust: 3,000 lbs. (1,360 kgp.) (4x General Electric G.E. T-58 gas-turbines)

Crew: 2, accommodation for 6 passengers

Armament: None.

References for this article:

Hopefully this will add to this topic. By the way, the Convertiplano was never cancelled and never made anywhere near 300 flights, if any.

This text is taken directly from the article that I wrote and published so no plagiarism. ZandoviseZandovise (talk) 18:22, 6 February 2013 (UTC)