An Easy-Flying Ultralight
Let’s see. A single-seat plane that can be purchased as an ultralight,
assuming your engine selection doesn’t push it over Part
103’s weight limit, or built from a kit and registered as an
Experimental-class aircraft, or purchased as a light sport aircraft
once the manufacturer meets the ASTM certification. What’s a pilot to do?
That’s the conundrum facing T-Bird I shoppers. This single-seater can be
a Part 103-compliant ultralight when using a Rotax 277, still available on
the used-engine market, though no longer supplied from Rotax’s Austrian
factory. Few prospective owners would select this engine, yet a more powerful
engine would push the T-Bird I over the Part 103 weight limit. Does that
leave only the Experimental amateur-built kit
The answer is no, and yes. To explain this apparent
contradiction, a kit-built T-Bird I with a larger
Rotax engine or the 60-hp HKS 700E engine could
still qualify under the 51% rule. But the most
recent news is that current T-Bird producer, Indy
Aircraft, is pursuing Light-Sport Aircraft certification.
They’re currently working on the T-Bird II and
plan to get the T-Bird I certified afterwards. When
completed – and given the long history of this
design, it seems reasonable to assume they can
meet the requirements – Indy Aircraft could supply
a fully built Special LSA (SLSA) and/or an
Experimental LSA (ELSA). Following such ASTM
certification, Indy would have the opportunity to
sell T-Birds in four configurations: Experimental
amateur-built, SLSA, ELSA, or even Part 103, if
you could find the right engine and restrict empty
weight to a minimum.
In addition to the regulation-driven choices, Indy
Aircraft can also supply these aircraft in a variety
of formats. For example, you can choose taildragger
or tri-gear form; wheels, skis, or floats; joystick or
control yoke, plus you have cockpit configuration
options. Finally, you have a number of engine choices.
The tri-gear T-Birds manage to look different
from the taildragger models, more so than some
other ultralight designs that have gone through
similar development. T-Birds started life solely as
taildraggers with nose enclosures and often used
the 65-hp Rotax 582 engine. Under Indy Aircraft’s
new plan you can mix and match any features
offered by the Iowa-based factory.
For example, a single-place T-Bird I could be fully
enclosed and powered by the 60-horse 4-stroke
HKS 700E, which would make it a lively performer
with great reliability, low fuel consumption, and
modestly priced. Such equipment would not detract
from the appealing simplicity of the T-Bird I and,
thanks to the basic design qualities, the machine
could be reconfigured, depending on the kind of flying
you wish to do.
When you remove the doors – typical of summer
flying in Indy Aircraft’s easygoing, slow-flying
machines – entry is no more than grasping the
overhead forward support tube with both hands,
sticking one leg in and swinging your body onto the
seat. Then you bring in the other leg. You will want
to be sure you don’t put weight on the throttle lever
when entering the aircraft; it looks like a handle.
Entry requires stepping around the control wheel
(I much prefer joysticks, for handling, and for easier
All T-Bird models shine with an ability to handle
larger-sized pilots. Perhaps because former company
owners Bob Ellefson and Dale Kjellson are tall
men, T-Birds accommodate tall or wide pilots with
more comfort than many aircraft. A former
enlarged cabin option has now been made standard.
All T-Birds, especially the single-seater, offer
superb visibility because you sit at the wing’s leading
edge surrounded by clear plastic. Without the
optional doors, I found the T-Bird I a little chilly,
even on a relatively warm day. The cooling effect
derives less from wind striking you than from air
being drawn swiftly out of the cabin.
The seating position is quite comfortable in both
the T-Bird I and II models, though upper back support
was a bit limited. However, I enjoyed a bit of
room to wiggle my feet and stretch my legs, thanks
to the T-Bird’s spacious cabin.
My assessment of the seat support and comfort
rings a bell with Indy Aircraft owner Bret Kivell.
“We’re working on an alternative,” says Kivell. “The
T-Bird I that we had at AirVenture Oshkosh ’07
was rigged with a low-cost executive office chair,
and had incredible back and head support. It completely
changed the whole flying experience and
almost made turbulent flying fun!”
Taildragger or Tri-Gear
In my experience, the T-Bird’s nosewheel is
tougher than many. Experienced pilots often take
care in lowering an airplane to its nosewheel upon
touchdown. The T-Bird I’s robustness is worthy,
given the way the plane tends to settle rather firmly
on its nosewheel.
Ground handling in the T-Bird I is very good. The
nosewheel is highly steerable and offers a tight
turn radius. Nosewheel suspension is also quite
good; it absorbed the bumps of a turf runway quite
well. I also found the T-Bird very stable on its steel
gear. It tolerated turns at speed. Though awkwardly
placed, the overhead brake is reasonably convenient
once you get used to the unorthodox location.
The T-Bird proved to be a most enjoyable companion
aloft. Well-behaved and adequately responsive
for most needs, the T-Bird I has sufficient performance
and feels solid. Some details can amplify
this basically good report.
As I performed my familiar Dutch roll coordination
exercises, I found the control wheel linked to
pushrods brought a full usable range in control
applications. This may be one advantage of control
wheels. Joysticks sometimes can’t reach their
range limit because the pilot’s
legs get in the way.
Throughout these roll reversals,
and those I would do later
in the steep bank series, I
found the all-pushrod linkages
were very smooth, making the
control pressures entirely reasonable.
Roll control was not fast,
averaging 3.5 to 4.0 seconds in
the 45° to 45° roll reversal. The
controls harmonized well, that
is, rudder and ailerons had reasonably
(one didn’t dominate the other).
The combination of roll rate,
harmony, and ease of control
pressure made my Dutch rolls
work quite well. I could not sustain them to high
bank angles, but that’s expected with only moderate
control response rates.
Whipping around abruptly in the T-Bird was a
joy; the plane responded well to control input and
retained a solid feeling throughout.
Some pilots have been critical of the robust
frame, which transmits this solid feel. Many years
ago, Dale Kjellsen, who founded the Teratorn
Aircraft Company, had an elaborate airshow display
where a bare-framed Tierra – precursor of the
T-Bird series – rotated on a moving platform. This
revealed the construction of the then-new design.
That same display also prompted critics to use the
phrase, “built like a truck,” when describing the
Stalls and Stability
A series of stalls in the T-Bird proved uneventful.
Power-off stalls brought a break, but so moderate
as to be difficult to identify. For most pilots –
certain beginning aviators – this behavior is a
Power-on stalls brought only a mushing flight;
however, the rate of sink rose dramatically. In
cases like this, I believe a break or shudder is
desirable to identify the onset of stall. Otherwise,
a pilot taking off at stall might not clearly see the
error of his slow-flying ways.
I could not induce an accelerated stall, partly
because I ran out of backstick. Once again the
mush-mode flight occurred.
Stall speeds seemed to agree with the figures
printed in the company’s brochures. Of course, this
depends on airspeed indicator
accuracy and I had no
way to ascertain that quality.
Stalls came about 26 to
28 mph indicated. This is a
comfortably low number
that assured me landings
would be easy.
My stability checks evaluate
pitch oscillation recovery.
I set the power and trim
to find a good cruise attitude.
Then, without other
changes, I pull back on the
stick to about 25° to 30°
nose-up, then release the
stick and watch. The same
maneuver is repeated nosedown.
The T-Bird I was
quite well behaved, moving
back and forth through
about 2 to 2.5 oscillations
before returning to approximately
I also like to investigate
engine-off sink rate performance.
Glide angle and
sink rate are the two performance
parameters in a
soaring machine, but it’s
important to know an airplane’s
capabilities in all
aircraft. The potential for a
stopped engine brings particular
focus on these two
The T-Bird I earned a
respectable 400- to 425-fpm
sink rate measured over 2
minutes of descent at what
felt like optimum speed. A
pilot more familiar with the
subtleties of the T-Bird I
might be expected to do better.
Not one to stay with current
reports Indy Aircraft is also
working on streamlining materials. “Another
design factor we are working on is reducing the
drag by incorporating more streamlined tubing,”
he says. “Streamlined struts are some of our more
popular options ($800). The difference is very significant,
especially with sink rate.We are
looking at streamlining other areas as
well. Of course, we should pick up some
cruising speed, but the sink rate should
The T-Bird I offered some highly enjoyable
flying, but long cross-country flights
are not one of the design’s strengths.
Kivell agreed. “The cross-country limitations
of the T-Bird are indeed its biggest
cons,” he reports. “We intend to improve
the comfort and ergonomics of the plane
so that cross-country flight is more enjoyable.
Also, doing some clean-up work on
the plane to reduce some drag should
help us pick up a little more cruise
speed.” The objective is to have a simple,
low-cost plane that is very capable of
making “breakfast runs” within a 100- to
150-mile radius. “We want to get the cost
of that $100 hamburger down to $25,”
Kivell adds with a smile.
Lower stall speeds generally suggest easier
landings. Slow approaches also assist in making
Landings were a “cakewalk.” Approaching at 40
mph, I was well above the 1.3-times-stall rule, yet
I was not streaking toward the field. When I felt
certain I would make the field, I relaxed my forward
stick and slowed to about 35 mph.
Touchdown occurred just below 30, making rollout
Every one of my landings was good. I did not
experience any tendency to bounce back and forth
from tailwheel to main gear partly because the TBird
I that I flew didn’t have bouncy tundra tires.
The Tierra was purposely designed to sit rather
heavily on the tailwheel. On the single-place TBird
I, this design concept works better than on
the 2-place T-Bird II, which is heavy to ground
handle by lifting the tail.
Yet T-Bird tail-heaviness can make the taildragger
version more pilot-friendly to those without
taildragger experience. Taildraggers are off-putting
to many pilots without such familiarity. While
this fear may be less appropriate in most ultralight
designs – they are far easier than faster landing,
high-deck-angle general aviation taildraggers
– it is even less of a concern in the T-Bird I. A
weighty tail tends to keep the tail down, the exact
technique taught by instructors helping train new taildragger pilots. Combined with a broad stance and more
forward main gear, ground looping is improbable in the TBird
Takeoff was equally simple. You needn’t worry much over
stick position as the T-Bird responded well to either stick
aft or stick forward at throttle-up. Of course, you should do
the customary routine of throttle forward, stick forward to
lift the tail, and then ease back to clear the ground. I don’t
believe you could stand the T-Bird on its nose because of the
tail-heaviness, but even if you did, the pilot would probably
be at little risk because of the T-Bird’s strong airframe.
If I had a gripe, it was the way the T-Bird I fell to its nosewheel
briefly after the mains touched. I could not hold it off
except when using a higher power setting. Fortunately,
Indy Aircraft has additional plans.
Kivell comments, “Regarding the tri-gear, we are considering
a new design. The current system, though easy to
retrofit onto existing planes – besides making the plane
easily-convertible between configurations – adds a lot of
redundant structural weight and creates a lot of additional
drag. Our new design will be incorporated into the fuselage
framework, and the main gear system will use streamlined
“The new design is intended to give a cleaner look, reduce
weight, and reduce drag at what should be lower cost. Also,
a lot of the tail structure is built to accommodate the heavy
weight of the tail design. Some of this can be reduced if we
go to a tri-gear.” Although this refit is progressing, Kivell
could not say when Indy Aircraft would have this revision
ready to go.
Further to the tri-gear design, Kivell reports, “[Former
Golden Circle owner] Bob [Ellefson] designed the tri-gear
with the mains abnormally aft, so that the nosewheel would
stay on the ground even when empty, which eases entry
into the cockpit – a real plus. But with the mains that far
back, it does indeed make for unorthodox takeoff and landing
characteristics. It’s an interesting tradeoff.”
The single-place T-Bird I stalled at about 32 mph. In comparison,
the 2-seater stalled at about 35 mph with power
off. The T-Bird I power-on stall occurred at about 20 mph
and went into mush mode. It was almost impossible to
detect a precise moment of stall.
Accelerated stalls acted like they might fall to the outside
wing but never did. These qualities are among the mildest
accelerated stalls I’ve experienced even though I was
banked to 45° and used cruise power (5,500 rpm).
The T-Bird I is a well-built, docile-handling, and predictable
aircraft with a number of good characteristics.
It boasts an excellent rough-field capability (with or without
the tundra tires), and should wear well. The designs
have a long track record with at least 1,500 of them
flying (in both single- and 2-place configurations). The number
could be closer to 3,000 airframes, but with various ownership
changes, some records were misplaced.
For years, the T-Bird I has been known as a
very easy-flying aircraft. Literally, if you feel challenged
flying a T-Bird I, you need more flight
training. I put the T-Bird I very high on my alltime
list for sheer ease of operation.
The T-Bird I’s roll rate is more docile than most
light aircraft, though it’s comparable to other aircraft
that can operate in this speed range. And
aircraft that fly as slowly as a T-Bird I can offer a
great platform for a kind of flying I consider
Low flying is simply the ability to enjoy the
American landscape really close up. While you’ll
want to conduct low-flying operations over open
fields that offer easy emergency out-landings, it
brings a pleasure you can’t find in faster, more
expensive aircraft. And even among ultralights
that can safely conduct such flying, few of them
will be more fun than a T-Bird I. It offers low
speed, good handling, and an easy-flying nature
that never goes out of style.
If you’re looking for a speedster, you have many
other choices. But the T-Bird I is a dependable
and enjoyable bird with a good reputation. It is
priced right at $12,850 for the T-Bird
I kit in taildragger configuration
with a 42-hp Rotax 447. The basic kit
comes with simple, but adequate
instruments: tachometer, ASI, CHT
gauge, and altimeter. Without
options you get a nose fairing, but not
a full enclosure.
However, the most popular option
is a full enclosure, which costs
around $500 when ordered with a
new kit. Brakes cost $450 and the trigear
option, at $1,200, is very popular,
says Kivell, president of Indy
Aircraft. Any T-Bird can be converted
back and forth between tri-gear and
taildragger in a few hours, he adds.
Two other popular options are wing
tanks with 20 gallons total capacity
for $600, and streamlined struts for $800.
You also may select more powerful engines: the
50-hp Rotax 503 costs $1,000 more and the 65-hp
Rotax 582 is $2,700 additional. All prices are subject
to change, especially imported items such as
engines; check with Indy Aircraft for the latest
The joystick remains available on special
request, but the yoke configuration has been virtually
the only offering for several years, says
I believe the T-Bird I, which is genuinely affordable,
has a solid future for those who enjoy boring
holes in the sky on a beautiful day. Give business
owner Bret Kivell and his team a call and see
what they can do to put a high-flying smile on
|Empty weight||290 pounds|
|Gross weight||590 pounds|
|Wing area||154 square feet|
|Wing loading||3.8 pounds per square foot|
|Useful Load||300 pounds|
|Payload (with full fuel)||270 pounds|
|Cabin Interior||28 inches|
|Height||6 feet 6 inches|
|Baggage area||Aft of seat|
|Airworthiness||EAB, SLSA, ELSA, Part 103.|
|Standard engine||Rotax 447|
|Power loading||8.9 pounds per hp|
|Cruise speed||55-60 mph|
|Never exceed speed||95 mph|
|Rate of climb at gross||700 fpm|
|Takeoff distance at gross||100 feet|
|Landing distance at gross||150 feet|
|Range (powered)||approx. 1.5 hrs; 105 miles|
|Fuel Consumption||about 4.0 gph|
|Standard Features||Rotax 447 with B Gear Box, taildragger
configuration; 15×6 tires; aluminum wheels; lap seat
belt; 5-gallon fuel tank; sewn Dacron wing, tail and nose
cover; tachometer; single CHT gauge; airspeed indicator;
Warp Drive 2-blade prop.
|Options||Various engines; IvoProp or Warp Drive 3-blade
prop; full cabin enclosure; speed struts; tri-gear assembly;
tail strobe; 12-gallon fuel tank or 20-gallon wing tanks;
deluxe instrument panel and a selection of instruments;
shoulder harness; color choices; powder-coated airframe;
hydraulic brakes; tundra tires; vortex generators; cabin
heat; dual wing tip strobes; float system; BRS parachute
|Construction||Aluminum airframe, welded steel components,
sewn Dacron wing and tail coverings, stainless steel
cable bracing. Made in USA; distributed by American company.
Cosmetic appearance, structural integrity, achievement of design goals, effectiveness of aerodynamics, ergonomics.
Pros – Now a well-proven design with many in
the field, a T-Bird I could satisfy your flying bug at
affordable prices. Robust frame, up to rough-field
operations. Solid in-air feel. Enclosure offers good
protection from elements. Many configurations
available to personalize a T-Bird to your desires.
Cons – The T-Bird is not a cross-county
machine. To some eyes the airframe looks bulky and
brute. To others, the T-Bird I appears to be a
Quicksilver knockoff. It would be hard to keep the
T-Bird I light enough to meet Part 103 weight limits,
though Indy Aircraft offers other choices.
Subsystems available to pilot such as: Flaps; Fuel sources; Electric start; In-air restart; Brakes; Engine controls; Navigations; Radio; (items covered may be optional).
Pros – Very simple plane, not a lot of systems
to manage. Given pending LSA approval or building
a kit under amateur-built rules, you could choose
from a long list of options, including 4-stroke
engines, skis, or amphibious floats. Good repair
Cons – Extremely limited in systems if you
wish to make a Part 103-compliant version. The
control panel area is quite limited in both the TBird
I and II. No flaps are available. No brakes
were installed on the test T-Bird I.
Instrumentation; Ergonomics of controls; Creature comforts; (items covered may be optional).
Pros – Enclosure does a good job of protecting
you from windblast without limiting visibility.
Seating is very comfortable (at least after you get
used to the rather reclined posture). A more spacious
cabin lets you move around a bit to flex your
legs and feet. Entry and exit are easy. Bigger pilots
will appreciate the T-Bird I’s roominess.
Cons – Seat posture seems overly reclined;
when angled back some support structure blocks
lateral view. The plastic enclosure can get hot in
summertime flying. Entry around a control wheel
seemed more awkward than getting in around a
joystick. Noise level was rather high (though a 4-
stroke engine would be quieter).
Taxi visibility; Steering; Turn radius; Shock absorption; Stance/Stability; Braking.
Pros – Very stable ground handling. Fairly
tight turning ability even in nosewheel configuration.
The T-Bird’s broad stance is helpful in crosswind
conditions. Visibility is excellent for traffic
checks. No forward visibility restraints when in
Cons – For manual ground handling, the TBirds
are rather tail-heavy (though the airframe is
strong enough that you could push on them almost
anywhere). The tailwheel was quite small when
operated on soft surfaces. No brakes installed on TBird
I (though it hardly needs them, if you plan
Qualities; Efficiency; Ease; Comparative values.
Pros – Superbly easy takeoffs and landings at
very low speeds; arguably the very easiest I’ve ever
flown. Very short takeoff run or ground roll even
without flaps. Strong gear permits off-field landings
within reason. Good control authority for crosswind
Cons – Some tendency to drop on the nosewheel
on landing in spite of pilot input to hold it off (when
no power is used). Exercise care if equipped with
tundra tires; the balloon tires can cause an unwanted
bounce if technique is wrong. Some pilots fear
taildraggers in general (they should choose the
Quality and quantity for: Coordination; Authority; Pressures; Response; and Coupling.
Pros – Controls are smooth through exclusive
use of pushrod linkages. Very good pitch response;
won’t get away from newer pilots. Though not fast,
roll/yaw controls are more than adequate. Response
is predictable in all axes. Coordination between controls
Cons – Roll rate is hardly fast if that’s what
you’re seeking. Control wheels tire the arms and
make entry harder; when they hit the stops, you’re
out of control motion. Stick range on very steep
turns is limited, especially in pitch.
Climb; Glide; Sink; Cruise/stall/max speeds; Endurance; Range; Maneuverability.
Pros – The T-Bird I speed range includes very
low-speed stall and moderate cruise at 55 to 60
mph. Marvelously easy landings. Sink rate is above
average. Performance will meet the needs of pilots
seeking a fun flying machine (though not for longer
cross country flights). Good climb if not trying to
stay within Part 103 parameters.
Cons – Entry level-capable ultralight offering
only moderate performance in all categories. Pilots
wishing to make cross-country flights should look
elsewhere. Two-stroke engines bring added noise,
vibration, and fuel consumption, but LSA approval
would open the door to 4-stroke powerplants.
Stall recovery and characteristics; Dampening; Spiral stability; Adverse yaw qualities.
Pros – Excellent, forgiving stall characteristics.
Turning stalls don’t tighten up on the low wing.
Good pitch dampening. Power-on stalls mush only,
never break. Opportunity for safe, slow-speed
approaches would help newer pilots. Adverse yaw
Cons – Stalls, though very modest in action,
don’t occur with much warning from aircraft; that
is, no burble or shaking identifies them. No parachute
on test aircraft (though offered as an option
from the factory). Lap belts only are insufficient to
many pilots; select optional shoulder harness.
Addresses the questions: “Will a buyer get what he/she expects to buy, and did the designer/builder achieve the chosen goal?”
Pros – The T-Bird I is a proven, low-cost choice.
Configuration versatility is excellent, most pilot
interests can be satisfied. Great visibility. Colorful
airframes appeal to many, offer personalization.
Available as a Part 103-compliabnt ultralight or
51% kit; later as SLSA or ELSA. Indy Aircraft is a
stable business associated with other enterprises.
Cons – For those who have accepted the new
world of light sport aircraft, the T-Bird may seem a
dated design with low performance (though this
depends on what you truly want from your sport
plane). Clear cockpit enclosure can be hot in bright
sunshine. Long option list can bid price up considerably.
Mark Lee Diedrich says
Dear Dan, my name is Mark Diedrich we bought a used terra with a 447 tail section is like new but the wings are another matter although ok to fly I would like to re cover having trouble finding them can you help.
Dan Johnson says
I presume you mean a Teratorn but I’m not sure as you are responding to an article about T-birds. That’s a rather old design and you may be quite challenged to find new wing sales. Some sailmaker might custom build such a thing but you might not like the price.
Great article. Please refer me to a T-bird II instructor.
Dan Johnson says
Hi Brian: Thanks for the kind words. T-Bird instructors will be hard to find, but the design is quite similar to a Quicksilver and you can find instructors for that. Check with Air-Tech in Louisiana; they may have suggestions. Or, visit the Quicksilver pilot’s Facebook page.
Russell Jaremicki says
Hi, by aluminum wing I did not mean totally aluminum including the wing cover. I meant the inner structure (spars and ribs), I have seen ribs made of plywood with aluminum spars. I don;t know if these plywood ribs are a t bird original or some individual’s idea. I have also been told of some real heavy duty wing covers, much thicker than regular dacron, that is being used. Is this specific for certain years? I don’t know if these heavy sails are something after market or original, thanks Russell
Dan Johnson says
As these aircraft were homebuilts, they can use any materials. No factory T-Bird had plywood in any part of the construction.
Russell Jaremicki says
Hi, have read many ultralight aircraft assessments and watched many of your video reviews. I am interested in purchasing an early ’80s T-Bird Tierra from Golden Circle. I am not sure really what year or what the correct model actually is. It has an all aluminum ribbed wing, and a Rotax 277 engine that is mounted on the root tube underneath the wing. The seller says he can not find a single piece of information on the airframe to help identify its true age or model. Maybe he does not know where to look? I tried to make contact with Indy Aircraft for some help on this, but got no answer. People have said that you have to give them a security deposit of about $1000.00 before they will communicate. HELP! Keep up the good work! Thanks Russell
Dan Johnson says
Hi Russell: I know the Tierra, which actually came out before Golden Circle got involved and promoted their T-Bird line. I think the original company was called Iowa Light Aircraft (or something similar) and the proprietor/designer was Dale Kjellsen. Indy Aircraft took over after Golden Circle and we had contact with both for a while, but not for some time now. Something is in error with your description, though. The Tierra never had an “all-aluminum” wing. Like most such aircraft, it used Dacron wing coverings with aluminum ribs in sewn pockets to create the airfoil. I recall it was a good flying aircraft with the little Rotax, which itself has long left the market. Good luck and thanks for the kind words about our video reviews.
Gerald King says
I am having the same problem, Indy Aircraft won’t communicate at all. I have e-mailed them, and left voicemails; I got no results!!! I would like to buy a copy of the building instructions, and, or flying instructions. Since Indy is non-responsive, there should be no legal problems.