| by |
Dave Higdon |
| Photographs by Dave Higdon and Eagle Aircraft
|
So
many pilots forget, or never knew, that the earliest heavier-than-air birds
pretty much all flew beak-first. But check out any photo of the Wrights'
earliest machines and some built by their followers ... the canard. Strange that
the canard never really became an industry standard, long ago overshadowed by
"backward-built" airplanes, those with the tail surface in back, in
one of many variations: cruciform, conventional, T-tail and V-tail.
And the forewing-first idea still suffers, in my view, from the unflattering
translation of the French word applied to that surface: canard. After all, a
duck, by any other name ... or so it's always seemed. Not even modern
applications of the canard could retrieve it from the depths of degradation
heaped on the humblest wing of all.
But in the years since the experimental airplane movement has grown into
numerical significance, this odd duck of aeronautical design has enjoyed some
revivals, usually at the hands of designers impressed by the peculiar attributes
of flying tail-first. Burt Rutan has probably done more to reintroduce the
canard configuration airplane, with designs like the VariEZ and LongEZ, the
Boomerang, the Defiant and Grizzly, and even the Beech Starship 1. And speaking
of corporate airplanes, let's not forget the recently-resurrected Piaggio Avanti
P-180. Nor should we neglect a number of ultralight designs popular in the
1980s, including the Goldwing, the Eagle, and the Pterodactyl.
And
now, here it is again, revived by yet another team of believers at Eagle
Aircraft Pty., based in the farthest western reaches of down-under
Australia, out in Freemantle, near the port city of Perth. The canard's latest
revival is the Eagle 150B — no relation to any other airplanes, experimental,
factory-made or ultralight — in reality an unconventional three-wing machine
finished off in wholly conventional fashion with a tractor powerplant up front,
tricycle landing gear beneath, and a familiar vertical stabilizer with rudder in
back.
Attached to all these conforming touches are creative ideas designed to ease
the assembly and service of the machine, and the interface with humans flying
the airplane as a trainer and a personal transport. Interestingly, the
human-interface touches completely complement both of the differing roles of
trainer and transport and detract not at all from each other.
Lifting the entire amalgam of airplane are those three surfaces, a forewing
with flaps, a main wing with both flaps and ailerons, and a horizontal stab with
elevators.
Up front is the wholly conventional power of a 125-horsepower IO-240
four-cylinder engine from Teledyne Continental Motors, and a two-blade
fixed-pitch aluminum prop from McCauley Propeller. In the avionics stack are
radios familiar to the world; and the arrangement and selection of instruments
and gauges conform to flying-machine convention, with some innovations for
enhanced awareness.
As the second incarnation of Eagle Aircraft's original 1988 design — then
dubbed the Eagle X-TS 100 — the Eagle 150B possesses great potential as a
modern, enjoyable trainer, as a cost-efficient rental airplane, and as a
personal transport for someone more interested in comfort and capability than in
the lowest possible cost.
And if Eagle Aircraft continues to evolve the Eagle 150B, from both a utility
and a production perspective, this unusual-but-cute bird could well become a
major player in the small field of two-place airplanes.
The Eagle: What's In A Name?
If you're at all versed in some of the giant names of general aviation
design, you certainly recognized Burt Rutan's name when dropped earlier; you
might even recognize the name of the primary designer of the Eagle X-TS 100, and
thus the Eagle 150B: John Roncz.
Roncz has
had a hand in some of aviation's most innovative and enduring designs, either as
a member of the team, the main man, or as an airfoil expert and creator, the
role which makes him much-sought-after by other designers. But in the case of
the Eagle, Roncz was the go-to guy tapped by the fledgling company.
And with the project in hand, boy, did Roncz go.
Basically, the Eagle is a tri-wing airplane, as we described above, built
almost entirely of various composite materials, used alone and in combination to
address specific structural needs. For example, the main gear is a single-leaf
affair constructed of fiberglass, to give it the shape and spring desired.
The canard, wing and tail section, which begins at the fuselage immediately
aft of the main wing, are mostly carbon fiber and Nomex honeycomb sandwich; the
cabin structure, however, incorporates a substantial amount of Kevlar to enhance
crash-worthiness and occupant protection.
The tail section, with the two stabilizers, the elevators and rudder, attach
to the main fuselage with a series of stainless steel screws into a ring
structure built around the aft cabin bulkhead. Before my flight in the Eagle,
the folks at U.S. distributor HGL Aviation in Augusta, Kan., showed me an Eagle
as it comes out of the shipping crate from Australia. Seeing the structure
erased any questions I had about the strength of the union.
And
then there are those wings. First, there's the quality of the work. Roncz
designed some interesting surfaces that might be duplicable in metal, but it's
hard to imagine achieving the same smooth, seamless finish achieved in
composites— especially in the most-compound curves.
First, thanks to the geometry and power of those lifting surfaces, the entire
package spans only 23 feet, six inches— barely over two feet more than the
Eagle's overall length of 21 feet, two inches. Each main wing is split into two
distinct sections by a large fence. Inboard of that fence, the trailing edge of
the wing is flap; outboard, the trailing edge becomes aileron. Further, up front
on the aileron section of the wing, the leading edge camber is a larger radius
and more pronounced; just beyond the leading edge, the upper wing surface
outboard of the fence also wears a row of vortex generators.
The canard itself reaches only 16 feet from tip to tip, and about 90 percent
of the trailing-edge area is flap. The canard is constant-chord and constant
camber and sports no fence or other list-enhancing devices.
As you'll see when we fly the 150B, these design characteristics all exist
for a reason and, from my exposure, they all work.
Making Adjustments To The Eagle, And Vice Versa
One reason people keep reinventing the airplane is because they have their
own ideas for improving on what's come before. Think if it as, more or less, the
"build a better mousetrap" phenomenon. That's pretty much why early
20th-century designers started tinkering with what the Wrights begot nearly 100
years back.
So it's natural to find some things that require adaptation to use and,
perhaps, learn to enjoy the designer's particular perspectives.
And
just as the Eagle's external airframe configuration demands some allowances from
people with fixed ideas of how planes should be, the inside also is cause for
adaptation. Not uncomfortably unconventional or wacky, by what people generally
consider standard, but different in ways that work for pilots.
First, for example, the bathtub structure that makes up the cockpit has high
side walls. To enter with ease pretty much demands some practice using the
approved step area of the wheel fairing and a gear-mounted step. Conversely,
handling the latch for the big bubble canopy posed little challenge to master.
In another example, the design uses semi-reclining seats molded as part of
the fuselage structure. Adjustable rudder pedals let the 150B adapt to different
leg lengths, while the pilot's height goes unchallenged by the tall bubble
canopy. And somehow, the center-mounted stick, side-mounted throttles, and panel
controls fall easily to hand for people of most heights, although the shortest
fliers might want to consider thicker seat cushioning to move them closer to the
panel.
And before we leave the rudder pedals, you should know that on the ground you
steer the Eagle with differential braking, since the nosewheel casters
independent of the rudder linkage. Anyone with some Grumman time will have no
problem, once they adapt to the brakes. The Eagle does not use toe breaks, but
instead sports a clever linkage that comes into play after you've moved a rudder
pedal forward a couple of inches. After an explanation of how the brakes work —
it somehow didn't come up until past the midpoint of my demo flight — and a bit
of practice with that knowledge, the Eagle let me brake in a straight line or in
the arch of a turn. And the brakes proved plenty powerful at the little country
strip used for most of our landings and takeoffs.
Also,
about that center stick. For a South Paw like me, it works great, even better,
perhaps, than for the dominant majority. A right-handed pilot in the left seat
might find it uncomfortable to release the stick to copy clearances, work the
radio knobs and such. But, if you're ambidextrous, there shouldn't be a problem.
As for the throttles, there's nothing here to challenge you considering their
convenient side-wall placement.
Left- or right-handed, though, the Eagle 150B delivers some nice touches
through that center stick, including electric trim control, a push-to-talk
switch, and a button that activates the comm's frequency flip-flop. Of course,
you still have to take your right hand off the stick to handle the radio dials
and the mixture controls.
In fact, the center-placement of practically all the cockpit controls puts
them comfortably, conveniently in reach — of your right hand.
Something For Everyone? Maybe
The Eagle boasts attributes that are already attracting FBOs, flight schools
and rental-fleet operators. Among them are traits unrelated to its aerial
abilities.
For one, the Eagle's composite construction is designed to resist damage and
wear well; corrosion, of course, should never be a problem. Eagle Aircraft also
thought about upkeep in designing the 150B, resulting in a machine that requires
nothing more than common tools to maintain. Even engine work has been
considered, resulting in a split cowling fastened with quick-turns and only a
couple of screws; either half comes off for engine work.
And
with the cowl removed, it takes only about 15 minutes to remove the bolts, tubes
and cables needed to swing the engine away from the firewall — in its own
hinged engine mount. The engine mount pivots around the nose gear on two hefty
hinges on the port firewall, opening access to all the accessories mounted on
the back of the Continental and on the firewall.
A sealed oil-air separator is part of the firewall-forward package, reducing
demands for engine oil and belly clean-ups. And with all the right instruments
and gyros and radios, there's nothing missing for the recreational flier or the
full-service flight school.
The Eagle's designers attended to the CFI's needs by giving the 150B dual
flap switches, with the right-seat switch able to override the left-seat's
switch; a second control stick branches out of the main stick, with its own
push-to-talk (PTT) switch on top. And a separate PTT resides in the right panel,
where a CFI or second pilot can key the mic without touching the stick.
For the cross-country pilot, the Eagle has that powerful electric pitch trim,
plus a manual roll-trim control unheard of on this class of airplane.
Fortunately, the Eagle delivers a commandingly solid ride and formidable
stability in flight.
A Limo-like Ride In A Roadster-style Package
At least this aspect of the Eagle's characteristic came as no surprise.
Canards, when designed and weighted correctly, often deliver rough-air rides
smoother than a tail-last design in the same conditions. My first real exposure
to this trait came years ago in the right seat of a Piaggio P-180. Warm spring
day, lots of convective activity and a fair share of popcorn cumulus at about
4,500. The pilot of a Malibu Mirage gave me a ride around the display pattern of
a community-event fly-by and, when we returned, the Piaggio folks offered me a
turn around the same route in the Avanti.
Same
air, same time of day, same altitude and airspeed. Yet the difference in ride
felt, well, dramatic. Sure, both airplanes felt the bumps, but each reacted
differently. In the Piper, the bumps felt like bumps, with the airplane feeling
more like we were hitting speed bumps at 120 knots; in the canard-equipped
airplane, the airplane's reaction seemed more like we'd run over a broader,
more-gradual change in pavement height and lasted longer, to boot.
Sorry this isn't more scientific — something about the difference in
pitching moments and wing loadings and the like — and somewhat less tactile.
But tactile is what makes the canard different. In fact, the same difference in
ride manifested itself during a later, longer demo flight in a Beech Starship
2000A, and in a few hours flying the old Eagle XP ultralight back in the late
1980s.
Another factor for the Eagle, engineers tell me, is the close proximity of
the canard and wing and the wing and horizontal stab. Not close enough to make
it a biplane, but far closer than with most other canard designs, the engineers
explained that gust pulses — updrafts, downdrafts — come close to affecting
all three surfaces almost simultaneously, dampening pitching action from rapid
changes in air direction and contributing to the Eagle's stability.
Wing loading also influences the Eagle's ride and its reaction to turbulence.
We're not talking a lot of lifting area here, 111 square feet for a nominal wing
loading of 12.71 pounds per square foot at the Eagle's gross weight of 1,411
pounds.
But what little wing area there is gets split among three different surfaces:
39 square feet in the canard, 16 in the tailplane, and about half of the total,
56 square feet, in the main wing. Between the short maximum span — the main
wing's 23 feet, 6 inches — and the relatively high wing loading for its weight,
the Eagle pulls off a ride quality more akin to a large, 3,500-pound single than
the sporty, diminutive machine it is.
Of course, no one cares about a quality ride if it comes in an airplane with
crummy flight characteristics. And it's aloft where the Eagle's atypical
configuration and accoutrements come together.
Stable And Forgiving, Yet Nimble And Quick...
This little bird, whether you call it a canard, a severely staggered biplane,
or perhaps even a tri-plane, delivers training capabilities equal to or better
than any of its peers, at a price competitive with one, Diamond's Katana
DA20-C1, and well above another, the night- and IFR-approved Zenith CH2000.
In its performance, the VFR-only Eagle 150B fares quite well, with a cruise
speed of 120 knots and a full-fuel range that can span 520 nautical miles more
slowly to match a lower power setting.
But
in handling and maneuverability, the Eagle owns the class, thanks to its
peculiar airframe configuration. Making an airplane this fast, this efficient,
and more fighter-like nimble than you'd ever expect a trainer with only 125
horses requires a designer to find synergy among many competing traits.
For example, a basic battle designers often fight pits aircraft stability
needs against demands for maneuverability and sometimes the outcome isn't
pretty: airplanes inherently stable only within a narrow margin of speed, weight
and trim; some easily upset from trim only to become challenges to a pilot's
judgment and reaction time; others so insistent on stable flight as to be
truck-like in maneuvering flight.
And when the design is destined for the training market, another battle often
breaks out: forgiveness versus reality. In other words, make a plane too easy or
forgiving and students won't face challenges certain to arise in more-demanding
aircraft.
...Simple, Yet Simply Slick...
No one should accuse the Eagle 150B of flying like a slug. Set takeoff flaps
— marks on the canard's flaps make it easy — firewall the throttle on the
little Continental, and the bird accelerates quickly past 50 knots, where slight
aft stick pressure starts a smooth rotation and transition to positive climb.
Rudder control against a steady, 30-degree left crosswind proved smooth and
proportional. Thankfully, the rudder came in quickly, at about 25, because I had
not yet quite figured out the no-toes brake system. Once my brain engaged with
the system — push the rudder pedals beyond a couple of inches and the brakes
engage — my initial control lapses stopped.
Another trait that requires some exposure to master is in the trim changes
that accompany flap movement. Trimming the nose back as the flaps stow helps
cancel a slight pitch-down excursion; likewise, the same attention to trim, in
the opposite direction, helps keep the nose down as the flaps extend in flight.
At full throttle, the Eagle climbed easily at around 800 feet per minute
while indicating 105 knots and with a great view ahead. The cowling's scavenging
cooling-air outlets seemed to keep temperatures well in the green, even down at
the lowest airspeeds and highest angles of attack.
And angle is something the Eagle attacks with confidence.
Power to the max, pulling a steep left climb, the airspeed needle dropping
below actual stall speed, and all the Eagle wanted to do is drop the nose
slightly and resume its ascent. In straight-ahead, power-on, power-off stalls as
well, the canard stalled first, dragging the nose down well before the main wing
could get a hint about pre-stall buffet.
Thank the vortex generators, high-lift leading-edge cuffs and the substantial
stall fence that marks the outboard third of each wing. Between the canard's
slightly higher angle of attack, which causes the stall before the main wing,
and the special treatment of the aileron portion of the main wing, the Eagle
never feels even slightly mushy or soft in roll.
...And In Control
Throughout
the control envelope, the main wing's ailerons remained in full control of roll,
as if the Eagle was cruising wide open at its maximum true airspeed, 120 knots.
And up there at cruise speed, those ailerons load up only to the point that they
enhance stability.
But decide to crank it and bank it to 60 degrees, or beyond, and the Eagle
goes over with you as if it heard your thoughts; enhanced airflow over
substantial ailerons on a short wing — only 10 feet from root to tip on each
side — translates to roll authority aplenty.
Want to corkscrew around a silo? The Eagle will spin your cork in tight
turns, at angles that may tax your abilities to keep power and pitch in synch to
hold to textbook-standard altitude standards for the maneuver; but she'll do it,
nonetheless.
If anything may tax the up-and-coming Eagle pilot, it may be learning to
transition smoothly from cruise to approach attitude, and from there to a
landing flare. But those pitch changes that accompany flap use will encourage
students and veterans alike to make best use of the Eagle's powerful pitch trim
system.
As for getting used to the view over a bubble-topped, canard-winged bird like
the Eagle, that's an easy one.
Anyone
who enjoys a truly fun airplane to fly will take to the Eagle and quickly warm
to all its views.
A few turns around the pattern at airports in Benton and Augusta, Kan., did
it for me. Benton, a tiny country strip, often serves as my testing grounds for
small planes and ones claiming small runway needs. Only 2,600 in length, about
25 feet wide, Benton enjoys something of a cult status among its tenants and
fans.
After a half-dozen approaches and landings, using different flap and approach
configurations from slips to curves to the standard box pattern, nothing turned
up to refute the Eagle's claim. There was considerable reinforcement that the
Eagle 150B is a pilot's airplane. Landings did seem to work best by holding a
bit of power into the flare, which helped me keep the nose up throughout the
transition to touchdown.
That said, accommodating different approaches proved no problem. For example,
slips begun too close to the threshold and too high to hope for a normal landing
helped me bring the Eagle down to a point where landing was comfortable, leaving
plenty of runway to stop and taxi back for takeoff — and without seeing more
than half the runway. Normal approaches brought my runway use down to just over
one-third of Benton's asphalt.
Ditto for departures. With the brakes locked and power maxed, the Eagle made
its liftoffs consistently before the midpoint of the runway, even when the winds
diminished to single digits. But even with the winds cross and gusty, Benton's
runway seemed nearly excessive and Augusta's 4,200 feet seemed space enough for
multiple touch-and-goes — in a single pass.
By the end of my flight, when time came to look up performance numbers, the
numbers found felt on-the-money, rather than blue-sky optimistic: 1,143 feet for
the standard, 50-foot obstacle-clearance takeoff requirement; 1,198 feet for the
same-standard landing distance.
Going The Distance: A Question Of Balance...
So, to sum up, the Eagle 150B flown for this report proved: fast (120 knots
cruise); economical (6 gph at cruise power); nimble (120 degrees per second for
the roll rate seems about right); and almost-STOL capabilities. If the Eagle
lacks anything, it's in true two-person utility.
Now
before someone reminds me that a day/VFR-only airplane already has its limits, a
word: night approval is due soon; IFR approval remains an unanswered question.
So, looking at the Eagle as a day/night VFR airplane, with speed, range and
avionics comparable to a Skyhawk, the Eagle needs a bump in maximum gross
weight.
At its gross weight of 1,430 pounds, the Eagle possesses only 484 pounds of
useful load. Luggage capacity in three spaces — the hat shelf and a compartment
behind each seat — totals 100 pounds. Using the full 26 gallons of fuel
capacity eats up 156 pounds. It's not the worst in the world, and actually
comparable to the capacities and constraints of its competitors.
But it's hard to believe that the structure isn't up to, say, another 50 or
60 pounds, as long as the bird meets its climb-gradient marks; and at 1,500
pounds gross weight, the Eagle could take on 98 pounds of luggage, full fuel and
300 pounds of occupants. And other combinations of occupants, luggage and fuel
would still be realistic enough for some fun cross-country travel.
Of course, these changes could well come to pass, as HGL Aero in Augusta,
Kan., and Eagle Aircraft in Orlando, advance their work in marketing and sales
of the Eagle 150B.
And both the distributor and manufacturer are optimistic that some avenues
ahead could help actually lower the price from its current fully-equipped mark
of $121,000. That hope rests in putting some of the assembly work in Kansas.
...And Cooperation
Currently, Eagle Aircraft in Australia imports virtually all the materials
and components from the good-ol' USA, and manufacturers the 150B in a modern,
new factory southwest of Perth. But among those components are items such as
tires, tubes, wheels, and brakes, avionics, electronics, lights, even the
engine, its accessories and prop.
If
Eagle and HGL and the FAA can work it out many, if not most of those components
could avoid two Pacific crossings and, instead, come to Kansas for installation
by HGL. Virtually anything that isn't built integrally into the main airframe
sections could be installed in the States.
And the savings — from lower shipping and insurance costs, brokerage and
customs fees avoided — could be substantial, not including the reduced wear and
tear on the components themselves. Between an increase in gross weight and a
decrease in price, the Eagle could find itself alone in a niche within what's
already a niche market.
As we said before, the Eagle's only noticeable shortcoming is its payload,
and that figure could change.
The Eagle 150B still packs quite a lot of performance and capability into an
attractive, albeit unusual, package. Don't be surprised to see one ducking in to
your home field as the word spreads, beak first.