The Golden Circle Air T-Bird is a family of
high-wing
A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes.
A monoplane has inherently the highest efficiency and lowest drag of any wing co ...
,
strut-braced,
pusher configuration ultralight aircraft that was produced by
Teratorn Aircraft
Teratorn Aircraft, Inc. (named for the extinct ice age soaring bird) was an American aircraft manufacturer based in Clear Lake, Iowa. The company specialized in the design and manufacture of ultralight aircraft in the form of kits for amate ...
of
Clear Lake, Iowa
Clear Lake is a city in Cerro Gordo County, Iowa, United States. The population was 7,687 at the 2020 census. The city is named for the large lake on which it is located. It is the home of a number of marinas, state parks and tourism-related ...
from 1983 to 1989 and then
Golden Circle Air
Golden Circle Air, Inc. was an American aircraft manufacturer based in De Soto, Iowa. The company specialized in the manufacture of ultralight aircraft in the form of kits for amateur construction and ready-to-fly aircraft under the US FAR 1 ...
of
De Soto, Iowa
De Soto is a city in Dallas County, Iowa, United States. The population was 915 at the time of the 2020 United States Census, 2020 census. It is part of the Des Moines, Iowa, Des Moines–West Des Moines, Iowa, West Des Moines Des Moines metropolit ...
from 1989 until the mid-2000s. In 2011 the aircraft were back in production by
Indy Aircraft
Indy Aircraft Limited was an American aircraft manufacturer based in Independence, Iowa. The company specialized in the manufacture of ultralight aircraft in the form of kits for amateur construction.Vandermeullen, Richard: ''2011 Kit Aircraf ...
. The aircraft is produced as a kit for
amateur construction.
[Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, page B-60 & B-106. Cybair Limited Publishing, 2001. ][Teratorn Aircraft: ''1984 Teratorn Tierra II The Legend Continues...'', Teratorn Aircraft pamphlet, 1984.][Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook'', page 168-169. BAI Communications. ][Bertrand, Noel; Rene Coulon; et al: ''World Directory of Leisure Aviation 2003-04'', page 142. Pagefast Ltd, Lancaster OK, 2003. ISSN 1368-485X][Downey, Julia: ''1999 Kit Aircraft Directory'', Kitplanes, Volume 15, Number 12, December 1998, page 50. Primedia Publications. ISSN 0891-1851][Downey, Julia: ''2001 Kit Aircraft Directory'', Kitplanes, Volume 17, Number 12, December 2000, page 54. Kitplanes Acquisition Company. ISSN 0891-1851][Downey, Julia: ''2002 Kit Aircraft Directory'', Kitplanes, Volume 18, Number 12, December 2001, page 43. Kitplanes Acquisition Company. ISSN 0891-1851][Newby-Gonzalez, Tori: ''2004 Kit Aircraft Directory'', Kitplanes, Volume 20, Number 12, December 2003, page 59. Belvoir Publications. ISSN 0891-1851][Downey, Julia: ''2005 Kit Aircraft Directory'', Kitplanes, Volume 21, Number 12, December 2004, page 61. Belvoir Publications. ISSN 0891-1851][Vandermeullen, Richard: ''2011 Kit Aircraft Buyer's Guide'', Kitplanes, Volume 28, Number 12, December 2011, page 56. Belvoir Publications. ISSN 0891-1851][Bayerl, Robby; Martin Berkemeier; et al: ''World Directory of Leisure Aviation 2011-12'', page 61. WDLA UK, Lancaster UK, 2011. ISSN 1368-485X]
Design and development
The original version of the T-Bird family was the Teratorn Tierra which was introduced in 1983. The aircraft achieved early success in the ultralight market, particularly in its
side-by-side seating
Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction.
The original use of the term in English was in ''tandem harness'', which is used for two ...
version, the Tierra II. The design passed from Teratorn to Golden Circle Air in 1989 and the aircraft was renamed the ''T-Bird''. Golden Circle Air went out of business in the mid-2000s and the design was out of production until 2011, when Indy Aircraft resumed building them. Over 4000 of all models have been built.
The T-Bird is constructed from
6061-T6
6061 ( Unified Numbering System (UNS) designation A96061) is a precipitation-hardened aluminium alloy, containing magnesium and silicon as its major alloying elements. Originally called "Alloy 61S", it was developed in 1935. It has good mechani ...
aluminium tubing, bolted together, with the wing and tail surfaces covered in pre-sewn
Mylar
BoPET (biaxially-oriented polyethylene terephthalate) is a polyester film made from stretched polyethylene terephthalate (PET) and is used for its high tensile strength, chemical and dimensional stability, transparency, reflectivity, gas and a ...
-coated
Dacron
Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foo ...
envelopes. The cockpit area has a
Lexan
Polycarbonates (PC) are a group of thermoplastic polymers containing carbonate groups in their chemical structures. Polycarbonates used in engineering are strong, tough materials, and some grades are optically transparent. They are easily worke ...
windshield and optional zippered cloth doors. The basic versions have
conventional landing gear
Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Term ...
, with some models offering
tricycle gear
Tricycle gear is a type of aircraft undercarriage, or ''landing gear'', arranged in a tricycle fashion. The tricycle arrangement has a single nose wheel in the front, and two or more main wheels slightly aft of the center of gravity. Tricycle ...
as an option. The cockpit controls consist of conventional rudder pedals and
yoke
A yoke is a wooden beam sometimes used between a pair of oxen or other animals to enable them to pull together on a load when working in pairs, as oxen usually do; some yokes are fitted to individual animals. There are several types of yoke, u ...
control wheels. Construction time for the T-Bird I was reported as 60 hours.
The Tierra II introduced a 13-position trim system and also 13-position
flaps.
The T-Bird I can qualify for the US
FAR 103 Ultralight Vehicles
Ultralight aircraft in the United States are much smaller and lighter than ultralight aircraft as defined by all other countries.
In the United States, ultralights are described as "ultralight vehicles" and not as aircraft. They are not req ...
category if equipped with a light enough engine, such as the
Rotax 277
The Rotax 277 is a , single-cylinder, two-stroke aircraft engine, that was built by BRP-Rotax GmbH & Co. KG of Austria
Austria, , bar, Ă–stareich officially the Republic of Austria, is a country in the southern part of Central Euro ...
, although reviewers have indicated that due to the high-drag design the aircraft is under-powered.
PilotMix describes the T-Bird I as "the most respected kit in the industry, and for good reason. It is absolutely the strongest and the easiest ultralight to build." Reviewer Andre Cliche calls it "robust...heavy and solid".
Variants
;Teratorn Tierra I
:Original single seat model that first flew in 1983.
;Teratorn Tierra II
:Two seats in
side-by-side configuration
Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction.
The original use of the term in English was in ''tandem harness'', which is used for two ...
ultralight trainer with a choice of a
Rotax 503
The Rotax 503 is a , inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catlog'', pages 6-105. Leading Edge Airfoils, 1995.
As of 2011 the Rot ...
or
Rotax 532
The Rotax 532 is a two-stroke, two-cylinder, rotary valve engine, liquid-cooled, gear reduction-drive engine that was formerly manufactured by BRP-Rotax GmbH & Co. KG. It was designed for use on ultralight aircraft.Raisner, William: ''LEAF cat ...
engine. First flew in 1983.
;Golden Circle Air T-Bird I
:Single seat development of the Tierra I with an acceptable power range of , the standard engine is the
Rotax 503
The Rotax 503 is a , inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catlog'', pages 6-105. Leading Edge Airfoils, 1995.
As of 2011 the Rot ...
. Other engine options include the
Rotax 447
The Rotax 447 is a , inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catlog'', pages 6-105. Leading Edge Airfoils, 1995.
Design and development
...
and
Rotax 582
The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...
.
;Golden Circle Air T-Bird II
:Two seats in side-by-side configuration ultralight trainer, developed from the Tierra II. An acceptable power range of , the standard engine is the
Rotax 582
The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...
with the
Rotax 912 optional. Also marketed as the ''T-Bird Side-By-Side''.
;Golden Circle Air T-Bird III
:Three seats, with two front seats in side-by-side configuration and one rear seat or optional extended cargo space. The standard engine is the
Rotax 582
The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...
. Optional equipment includes agricultural spray gear, strut fairings and
tundra tires. First flown in 1990, 78 were reported flying in 2004. Also marketed as the ''T-Bird Cargo''.
;Golden Circle Air T-Bird Tandem TBT06
:Two seats in
tandem
Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction.
The original use of the term in English was in ''tandem harness'', which is used for two ...
configuration. The standard engine is the
Rotax 582
The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...
. Optional equipment includes agricultural spray gear, strut fairings and
tundra tires. First flew in 1992 and there were 21 reported flying in 1998. Discontinued around 2000.
;Indy Aircraft T-Bird I
:Current production single seat model. The standard engine is the
Rotax 447
The Rotax 447 is a , inline 2-cylinder, two-stroke aircraft engine, built by BRP-Rotax GmbH & Co. KG of Austria for use in ultralight aircraft.Raisner, William: ''LEAF catlog'', pages 6-105. Leading Edge Airfoils, 1995.
Design and development
...
. Construction time 100 hours.
;Indy Aircraft T-Bird II
:Current production two seat model. The standard engine is the
Rotax 582
The Rotax 582 is a two-stroke, two-cylinder, rotary intake valve, oil-in-fuel or oil injection pump, liquid-cooled, gear reduction-drive aircraft engine manufactured by BRP-Rotax GmbH & Co. KG. It is for use in non-certified aircraft operating ...
. Construction time 140 hours.
[Tacke, Willi; Marino Boric; et al: ''World Directory of Light Aviation 2015-16'', page 63. Flying Pages Europe SARL, 2015. ]
Specifications (Tierra II)
References
External links
Official websitePhoto of Golden Circle T-Bird{{Teratorn Aircraft
1980s United States ultralight aircraft
Homebuilt aircraft
Single-engined pusher aircraft
Teratorn Aircraft aircraft
Golden Circle Air aircraft
Indy Aircraft aircraft