Taking a kit aircraft company to full ASTM approval is a very big decision for small companies. Simply assuring you have documents to support a declaration is, by itself, a major task. Then comes a decision about fully building or going the Experimental LSA kit route. A company must first fully build and certify at least one Special LSA, but once done, they can elect to provide a kit only…or to factory build and supply kits. Small shops could fully build 20-30 SLSA and supply additional ELSA kits and parts to make a healthy business. *** We may finally see such entries. Recently I wrote an updated pilot report on the T-Bird I from Indy Aircraft. Boss Bret Kivell said Indy is working on approval. As an ELSA, the single seater could be HKS (four-stroke) powered, which would make it one sweet sport aircraft. Likewise development is underway at Paul Mather’s M-Squared Aircraft where his Sport 1000 could gain SLSA approval later this year.
Indy Aircraft Ltd. T-Bird II
Phone: (319) 334-2473Independence, IA 50644 - USA
|Empty weight||481 pounds1|
|Gross weight||1,000 pounds|
|Wing area||190 square feet|
|Wing loading||5.23 pounds per square foot|
|Build time||40-60 hours|
|Notes:||1Tri-gear setup reviewed in this article adds 30 pounds; costs $920.|
|Standard engine||Rotax 582|
|Power||66 hp at 6,500 rpm|
|Power loading||15.15 pounds per horsepower|
|Cruise speed||68 mph|
|Never exceed speed||95 mph|
|Rate of climb at gross||600 fpm|
|Takeoff distance at gross||300 feet|
|Landing distance at gross||250 feet|
|Standard Features||Side-by-side seating in taildragger configuration, strut-braced wings, nosewheel steering, airspeed indicator, tachometer, water temperature, cockpit enclosure (full except doors which are optional), 12-gallon fuel tank, Dacron® wing covers with no painting required, engine mount for Rotax.|
|Options||75-hp Rotax 618 or 80-hp 912 or Wankel rotary engine, tricycle gear, electric starting, streamlined struts, swing-up doors, cabin heat, hydraulic brakes, tundra tires, wheel pants, amphibious floats, additional instruments, intercom, strobe light, shoulder belts, ballistic parachute, 2- or 3-blade composite prop, agriculture spraying apparatus, quick-build kit (30-42 hours, according to factory).|
|Construction||Aluminum tubing, welded steel, Dacron® sailcloth with Mylar® finish.|
Cosmetic appearance, structural integrity, achievement of design goals, effectiveness of aerodynamics, ergonomics.
Pros - Tried-and-true shape that lends itself to ultralight flying. In my opinion the tri-gear T-Bird II is superior to the taildragger. New wing rib shaping yielded better flight characteristics. Golden Circle has long used brightly-colored airframes and Mylar-coated wing coverings to earn good first impressions.
Cons - Being well-rounded means the T-Bird does not stand out in a particular category. Design tends to run heavy for the load it carries. Taildragger model is quite tail heavy on the ground.
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 - Our test T-Bird II was equipped with brakes, in-flight-adjustable trim, electric starting. Primer and kill switches conveniently located overhead, and are not easily bumped. Plenty of interior room for tube-mounted radios or GPS units. Engine access is wide open.
Cons - Tri-gear T-Bird II requires N-numbers and FAA registration (though this means you can add systems without weight concerns). Panel space on the test T-Bird was limited. No flaps are available on any T-Bird. Brakes were nondirectional (though nosewheel is responsive enough to cancel need).
Instrumentation; Ergonomics of controls; Creature comforts; (items covered may be optional).
Pros - Overhead brake handle gives excellent leverage; system was hydraulic on test ultralight and worked well. Multiple detents on trim let you adjust by feel. Roomy cabin, one of the largest in its class. Full enclosure possible with optional gull-wing doors which attach quickly. Easily ground-adjustable rudder pedals permit a wide range of pilot sizes.
Cons - Test plane seat restraint limited to lap belts, which I consider insufficient. Fuel into the cabin-mounted gas tank adds gas odors to the interior. Angled back seat won't appeal to everyone. No easy seat adjustments. Your feet can get warm on hot days.
Taxi visibility; Steering; Turn radius; Shock absorption; Stance/Stability; Braking.
Pros - Nosewheel is very cooperative, actually superior to taildragger T-Bird II I'd once flown. Visibility is good in all directions for checking other traffic. Brakes on the test T-Bird were potent and the cabin lever offered excellent leverage. Main gear felt up to rougher runways; taxied stably throughout flight test. Good ground clearance for off-field landings.
Cons - T-Bird II is on the heavy side and taxiing it reveals this (although this can actually be helpful on windy days). Unidirectional brakes don't aid steering. Turn radius can be tighter with the right tailwheel than possible with nosewheel steering (common to many either-gear designs).
Qualities; Efficiency; Ease; Comparative values.
Pros - Thanks to rib-shaping changes, approaches can be made more slowly and still leave adequate authority for roundout control. Visibility is excellent on both departures and approaches; lateral visibility is also good to assure no traffic conflicts. Control is authoritative enough to permit landings with some crosswind component. Good clearance for rougher runways.
Cons - No flaps made slipping the only tool for controlling approaches (other than good planning and speed control). Tundra or extra-wide tires that Golden Circle likes have bounce-back-into-the-air potential. Approach speed, though better, is still higher than some similar ultralights.
Quality and quantity for: Coordination; Authority; Pressures; Response; and Coupling.
Pros - Yoke control will please many conventionally trained pilots (yokes are standard in general aviation trainers); joystick is optional for those who dislike yokes. Controls exhibit adequate authority for most conditions. Pitch is very stable (assuming you kept weight and balance within specs). No surprises in control actions.
Cons - Full-span ailerons have considerable adverse yaw like many similarly-constructed ultralights. Roll is not very fast on the T-Bird II. Balance between controls isn't perfect; rudder appears to take somewhat heavier use to coordinate with ailerons.
Climb; Glide; Sink; Cruise/stall/max speeds; Endurance; Range; Maneuverability.
Pros - With its new wing shape, the tri-gear T-Bird II held energy longer. New wing profile provided higher cruise speeds than earlier models, and lower stall speeds, reports the factory. Sink rate and approach glide angle were similarly improved in my attempts.
Cons - Cruise speeds aren't high on the T-Bird; that isn't their strength (which is fine with me but maybe not with you). Fuel burn seemed higher than average, possibly explained by the T-Bird's heavier weight. Climb seemed softer than expected given the new wing efficiency.
Stall recovery and characteristics; Dampening; Spiral stability; Adverse yaw qualities.
Pros - I found no evil characteristics, helping confirm the T-Bird line is good for newer pilots. Stalls were mild breaking and full-power stalls didn't break at all. Steep turns with liberal power carved smooth turns without a tendency to fall off to one side.
Cons - Full-power stalls wallowed around with high nose angles that felt like they could fall off to one side (though I never experienced this result). I'd much prefer shoulder belts or four-point seat restraint. No spins attempted; no parachute installed. Adverse yaw was significant. Throttle response was negative as it is on most high thrust line pusher ultralights.
Addresses the questions: "Will a buyer get what he/she expects to buy, and did the designer/builder achieve the chosen goal?"
Pros - Golden Circle is a mainstay of the ultralight industry, selling steadily over many years. Comfortable, easy-going style from company, leadership puts buyers at ease during purchase. Attractively-finished ultralights with bright powder-coated colors. Full enclosure available along with an impressive list of optional choices. New wing profile aids overall handling and performance compared to earlier models.
Cons - Design looks dated to some buyers. Weight-and-balance calculations need improvement, say some owners. Brute strong airframe carries some weight penalty. N-numbers and FAA pilot certificate mandatory with 12-gallon fuel tank and weight beyond 500 pounds empty.
As with many ultralight aircraft brands, when single-seaters become dual machines the machine gets heavier and more complicated. And when ultralights get heavier, they often don’t work quite the same. Since flight school operators and pilots wanting to carry a friend request 2-seat capability, ultralight manufacturers respond, trying to get as close as possible to single-seater feel. But this isn’t simple. Two-seat ultralights often give up some of the qualities that make a single-seater pure joy to fly. However, designers make constant refinements in ultralights. Look around at airshows. Most of the ultralights on display these days are well-built machines with lots of custom hardware. Nearly every one got that good employing the CANI approach – Constant And Never-ending Improvement. Golden Circle’s T-Bird II is one model that has seen subtle but noticeable improvements that make the breed better. Even to those intimate with the Iowa ultralight producer, these changes may evade your inspection.