Tessier Biplane

Designed by Rene Tessier and built in 1963, the Tessier Biplane is a single place homebuilt biplane.

The Tessier biplane is a single place tube and fabric construction aircraft with conventional landing gear. The wing spar is wood and ribs are plywood. The original engine was a Volkswagen air-cooled engine which was replaced with a Lawrance L-5 radial engine.

The original Tessier Biplane belongs to the EAA AirVenture Museum, but is neither airworthy nor on display.

Powerplant: 1 × Lawrance L-5 Five cylinder radial
Propeller: 2-bladed
Crew: 1

Terrafugia Transition

Terrafugia, a New England-based company has introduced the Transition. It’s a street-legal airplane that the company calls “the first step on the road to the practical flying car.”

At first glance, the Transition basically looks like a plane with collapsible wings that make it drive-able on city streets.

The carbon-fiber Terrafugia Transition is in development since 2006, and first flew in 2009.

On the road, it can drive 70 mph (110 kmh) and 93 kn (107 mph / 172 kmh) in the air and have a flight range of 425 nmi (489 miles / 787 km).

Nearing production in 2012, the price was holding at US$279,000 and more than 100 customers were waiting for delivery, possibly in 2014.

The Terrafugia Transition has received exemptions from the NHTSA that make it legal to drive on the road. With polycarbonate windows instead of automotive safety glass and tires not normally considered street legal, it has nevertheless passed muster for both the sky and the highway in terms of weight and safety.

The Terrafugia company had been doing lots of fine tuning since then to attain the proper licensing and exemptions needed to ensure these roadable aircraft are ready for delivery by the end of 2012.

Geely, the company that also owns Volvo, agreed to acquire Terrafugia in 2017. The Terrafugia flying car, created by a handful of MIT grads, received FAA approval in 2016 allowing the transforming car to be certified as a light sport aircraft. The exemption means Terrafugia can create a road- and air-legal vehicle that weighs up to 1,800 pounds.

Terrafugia’s Transition model, the company test vehicle, claims a range of 400 nm at a top speed of about 90 knots. The Transition air/car’s wings fold back to allow the craft to fit in a standard single-car home garage.

The Zhejiang Geely Holding Group confirmed that it is hiring engineers, who must be English-speaking, to help introduce and test-produce prototypes to produce flying cars in China. The company was also seeking contractors to renovate workshops in a passenger car production facility in Hangzhou, Zhejiang province, for the same purpose. Geely said it expects to finish the development of Terrafugia’s first model, TF-1, and launch it in the United States by July 2019.

Gallery

Transition N302TF
Engine: Rotax 912S, 100hp
Wingspan: 27’6″
Length: 19’2″
Useful load: 430 lb
Cruise Speed: 100 mph (160 km/h)
Stall: 51 mph
Range: 410 mi (660 km) plus 30 min. reserve
Mileage on Road: 35 mpg
Seats: 2

Teratorn Tierra

Single or side by side two seat single engined high wing monoplane with conventional three axis control. Wing has unswept leading and trailing edges, and constant chord; cruciform tail. Pitch control by elevator on tail; yaw control by fin mounted rudder; roll control by full span ailerons; control inputs through stick for pitch/roll and pedals for yaw. Wing braced from below by struts; wing profile NC; double surface. Undercarriage has three wheels in tail dragger formation; nylon rope suspension on tailwheel and steel spring sus¬pension on main wheels. Ground steering by differential braking. Brakes on main wheels. Aluminium tube framework, partially enclosed (totally enclosed optional). Engine mounted above wing driving pusher propeller.

One of the revelations of Sun ‘n’ Fun in March 1983 at Lakeland was the prototype Tierra with which Teratorn Aircraft made a spectacular entrance into that section of the ultralight market which is in direct competition with traditional light air¬craft. This machine offers the facility to be used either as a single seat ultralight or to be transformed into a US category experimental aircraft by the addition of a second scat, the problem of centre of gravity shift being resolved by positioning the single seat in the centre of a wide cockpit, so that it only has to be moved sideways to make room for two. The single stick is central and, as the Tierra has two rudder bars, it becomes a dual control machine when fitted with both seats.

The fuel tank is mounted behind the seating low down at the rear of the cockpit which closes with the clever use of zips for the side panels, the windows coming down to the lower longeron of the cabin. This enclosure is available as an option, as are isolation panels for the cabin. These are made of soundproof material and fit behind the cabin and above the wing and are easily removable. The structure of the Tierra is formed from triangular frames. All the joints in the airframe are reinforced with a strong high density elastic foam pressed into the tubes which absorbs vibration and eliminates metal to metal con¬tact.

Engine location is above the cabin, the motor using dyna focal mounts as in modern conventional aviation. It is a Rotax 377 cc unit fitted with a reduction drive and Teratorn’s own Flexidyne type clutch system. Finally comes an accessory which is still rare in ultralight aviation: the horizontal tail surface of the Tierra is fitted with a trimmer permit¬ting maximum stability in flight regardless of the load carried or its position.

Tierra
Engine: Rotax 377, 36hp at 6600rpm
Propeller diameter and pitch 60 x 36 inch, 1,52 x 0.91 m
Toothed belt reduction, ratio 2.6/1
Max static thrust 245 lb, 111 kg
Power per unit area 0.24 hp/sq.ft, 2.7 hp/sq.m
Fuel capacity 5.0 US gal, 4.2 Imp gal, 18.9 litre
Length overall 18.5 ft, 5.64 m
Height overall 6.0ft, 1.83m
Wing span 31.5ft, 9.60m
Constant chord 4.5 ft, 1.37 m
Sweepback 0 deg
Total wing area 142 sq.ft, 13.2 sq.m
Wing aspect ratio 7.0/1
Empty weight 253 lb, 115kg
Max take off weight 550 lb, 249 kg
Payload 297 lb, 135 kg
Max wing loading 3.87 lb/sq.ft, 18.9 kg/sq.m
Max power loading 15.3 lb/hp, 6.9 kg/hp
Load factors; +6.0, 3.0 ultimate
Max level speed 63 mph, 101 kph
Never exceed speed 63 mph, 101kph
Cruising speed 50mph, 80kph
Stalling speed 25 mph, 40 kph
Max climb rate at sea level 800 ft/min, 4.1 m/s
Min sink rate 300ft/min, 1.5m/s
Best glide ratio with power off 10/1
Take off distance 50 ft, 15 m

Tierra 1
Engine: Rotax 277
Empty wt: 253 lb
Max wt: 650 lb
Wing span: 31ft
Wing area: 154 sq.ft.
Wing loading: 4.22 lbs/sq.ft
Power loading: 23.21 lbs/hp
Max speed: 62 mph
Cruise: 55 mph
Stall: 26 mph
Vne: 75 mph
Seats: 1

Tierra 11
Engine: Rotax 532
Empty: 385 wt. lbs
Max wt.: 850 lbs
Wing span: 36ft
Wing area: 190 sq.ft.
Wing loading: 4.38 lbs/sq.ft
Power loading: 13.08 lbs/hp
Max speed mph: 75
Cruise mph: 60
Stall mph: 30
Vne mph: 80
Seats: 2

Tierra UL
Engine: Rotax 277 (268 cc) 28 hp
Static thrust: 180 lbs
Empty wt: 249 lbs
Wing span: 30’6”
Wing area: 155 sq.ft
Height: 5’8”
Length: 18’6”
Fuel cap; 5 USG
Construction: Aluminium, Dacron, Steel
Max wt: 500 lb
Stall: 24 mph
Max speed: 60 mph
Vne: 70 mph
Climb rate: 500-600 fpm
Design limit: +6, -3g
Glide ratio: 10-1
Wing loading: 3.23 lbs/sq.ft
Power loading: 17.86 lbs/hp

Tervamaki JT-6

Finnish company Eiri Avion started to build the PIK-20 B sailplane, an all-fiberglass/epoxy high-performance glider designed by a group of engineers (Tammi, Hiedanpää, Korhonen).

In 1975 an agreement was signed between Tervamaki and Eiri Avion to develop a retractable engine installation for the PIK-20B glider. The designation for the prototype was JT-6. It is a one-of-a-kind experimental machine used as a test bed for the production model which later emerged as PIK-20E (E for the engine).

The modifications necessary to convert a PIK-20B glider into a JT-6 motorglider were as follows:
Engine installation including a retraction mechanism with automatically opening and closing doors, fuel tank, a 16-Ah battery plus engine gauges and controls.
The engine and propeller necessitated enlargement of the fuselage aft of wing and, therefore, a new fuselage center-section mold was made. The fuselage was bonded together from three sections.
The engine compartment opening required a strong beam around it to carry the loads.
All of the above modifications added some 70 kg of mass and moved the CG 100 mm (4 in) backwards. To compensate for this CG shift, the wings were swept 2 degrees backwards, necessitating new wing spars and new wing root fittings.
The wing spars were strengthened due to the increased fuselage mass.
The main landing gear was moved 100 mm (4 in) backwards and a steerable tail wheel was added, as was retractable outrigger wheels into the wings.

Tervamaki first flew the JT-6 in August 1976, registered OH-520X. There were numerous difficulties in the beginning, and the first flight was a near disaster. The first engine, a Canadian Kohler, was of too low power (33 hp). In addition, the Kohler factory ceased working in 1977 but, a good, new choice was found in the Rotax 502. It was the first Rotax 502 installation in an aircraft. With the Rotax 502 the plane had a climb rate of 3.5 m/s.

Since the machine was an experimental prototype, a lot of things changed during the test flights and thereafter during the 20+ years of flying. The most serious ones are a couple of engine seizing due to too lean mixture.

An article about JT-6 appeared in Homebuilt Aircraft, August 1980. Self-Launch!, a book by Peter A. Williams from 1998 thoroughly describes motorglider history including the JT-6 in detail.

The JT-6 logged 1621 hrs in 23 years of flying of which less than 5 percent was by power, the rest was soaring.

The JT-6 was handed over in an airworthy condition to the Finnish Aviation Museum in May 2007.

OH-520X / T6