Why Light Twins are Underrated Those in the market for a plane that can carry
4 passengers always want a Cessna or a Cirrus. When they realise, they can’t afford one, they
consider other options. Single engine market has some pretty great offerings, but why don’t anyone
ever look in the direction of twins? if you define the GA twin engine plane market is as
dead, you wouldn’t be wrong. Diamond Aircraft control more than half of all GA twin sales,
because their planes are the best or the segment is
completely overlooked? how great are planes in this segment?
Twin trainers are the perfect solution to single engine personal planes. They can carry more, fly
just as fast, and farther. Kicking off with the Piper Seminole, anyone familiar with this segment
will know that this light-light twin has been a popular entry level twin almost from the start.
Offering lower operating costs than its larger-engine competition,
the Seminole is one of the easiest twins to fly because
of its counter-rotating props and it outsold the competing Duchess
handily. The Handling characteristics is respectfully nice,
not particularly responsive-especially in roll-but always honest and predictable
except for the quirkiness in pitch on takeoff and landing
due to the T-tail. If you take the
inconveniences of the T-tail aside, the Seminole is hands-down a great entry level
twin, minimum manoeuvring speed is 56 knots, the same as the flaps-up stall speed. That means
that you will almost never experience a violent roll off if the airplane is slowed below Vmc.
The best thing about this plane is the useful load,
1400 lbs is a lot to carry every bits and pieces of what you need for a cross country light. With
108 gallons of usable fuel, endurance exceeds five hours.
Prices for new Seminoles start at $700,000, but you can get a used model for $100,000, it will be
most likely beaten hard by student pilots and almost
invariably have a damage history. You can’t get a single with 1400lbs useful load, 1000
miles range, and 190-mph cruise speed. This plane being cheaper at the point of purchase does not
translate to cheaper operating cost. Twins are more expensive to operate, at the point
of overhaul, you have two engines to worry about, but if
you can afford a plane, you can handle that right? Moving
forward to the Diamond DA-42 Twin star. The DA42 is a plane that needs no
introduction, so good that many flight schools never considered it because it was perceived as a
lousy multi-engine trainer because it was too easy to operate. In the event of engine failure, the
pilot pushes the two power levers forward (FADEC and single-power lever operation mean there
are no prop or mixture controls), identifies the dead engine and
flips its off/on switch to off. The prop feathers automatically. That’s it.
We agree that the Twin Star is a poor trainer for someone who is going to have to make a living
and build time flying a piston or turbo-prop twin where engine shutdown is more complicated,
significant additional training will be required. However, the Twin Star is the perfect for
someone who wants a twin for personal commutes. Power management is jet-like, even to indicators
reading out in percent power and the need to carry significant power on final when the gear and
flaps are down is similar to jet operations. In addition, the long wings make control response in
yaw and roll ponderous when slow, much like larger airplanes.
The cockpit visibility is excellent, as well as the astonishingly low noise
level and smoothness of the engines and props.
On only 135 HP a side and with a 3935-pound gross weight, all-engine rate of climb exceeds
1100 FPM, however, the published single-engine rate of climb is atrocious-150 FPM at sea level.
The single-engine service ceiling is 4000 feet. Realistic cruise speed is 145 knots on 12 to 14
GPH. With the main tanks full, endurance is about five hours and 690 pounds can be carried in
the cabin. Despite miserly fuel consumption, the life limit
on the gearboxes of the diesels and the engines themselves, as well as the need for specialized
training for technicians to work on the Twin Star, the DA-42 has proven painfully expensive for many
owners. The average annual inspection ran $12,000, before any squawks were addressed.
Operational costs plus amortization of the purchase price of a new twin means that rental
rates for the Twin Star that we saw hovered around the $340-per-hour mark.
Moving on to the Tecnam P2006T. With over 3000 airplanes produced, Tecnam is no rookie in
the aviation world. It used its experience making LSAs to come up with a twin that has a gross
weight of only 2712 pounds using a pair of the proven 98-HP Rotax 912 S3 engines.
Performance is surprising and impressive: despite being underpowered, the all-engine rate of
climb is over 1100 FPM, with cruise of 145 knots on a total of 10 GPH.
Fifty gallons of usable fuel gives an endurance of about 4:30. With the tanks full, it will carry
648 pounds in the cabin. The Rotax engines prefer mogas, plus
more and more shops have experience with Rotax engines, so Tecnams lightweight approach could
be the way to go for reasonably priced multi-engine training.
Priced at just over $600,000 equipped, the P2006T is at least $100,000 cheaper than the Twin
Star and Seminole. Even allowing for amortization of the purchase price,
and rental rates are under $250 per hour.
Because the engines only develop 98 HP, they can’t drive big alternators, each one only puts out
40 amps. That means load shedding if an engine fails in flight,
something that will help pilots in training to fly other piston twins.
The handling of the P2006T is great, it is precise in all axes and responded more as one would
expect in a heavier twin. The engines are not counter rotating, meaning you have a critical
engine. Visibility is
the best of the bunch; the pilots sit ahead of the engines. For what appears to be a
small airplane, the cabin is roomy and comfortable with plenty of leg- and headroom. Because of
the proximity of the props, the ability to open a window is limited. Although there is a good
ventilation system, the cabin can be uncomfortable on warm days.
On the other hand, cabin heat, as with the Twin Star,
comes from the engines instead of a heater in the nose-burning avgas as is
the case in most piston twins. The gear takes 18 seconds for
its cycle, which will work against you if you are trying to quickly
clean up the airplane following an engine failure shortly after take-off.
Finally, the Beechcraft Duchess Despite being out of production for over 30 years,
the Beech Duchess is still of value till today. Most pilots will never stop emphasizing its great
handling characteristics, and lack of quirks during takeoff and landing, Beech did its
T-tail right. The only problem with this plane is when it
comes to maintenance; parts are seriously hard to find.
Performance, on 180 HP a side, is on a par with the other twins, figure on a 140-knot cruise,
1000-FPM all-engine rate of climb, 250-FPM single-engine rate of climb and able to carry 631
pounds in the cabin with a full load of fuel of 100 gallons.
Handling is standard Beechcraft, stable and predictable, with pleasantly fast ailerons.
Steep turns and slow flight are without vice.
The counter-rotating engines mean stall speed is reached well
before Minimum Controllable Airspeed, all of which make this an almost too-easy trainer, much
in the Seminole model. The best thing is that it has two cabin doors;
which contributes to convenience and safety. The cabin is almost too big, an invitation
to overloading, a potentially fatal error when dealing with
the anemic single-engine rate of climb endemic to piston twins.
The Duchess will be on flight lines for some years to come because one can be purchased for
well under $100,000 and the hourly operating costs aren’t bad. However, considering that
demand will drop as students want glass panel, price will
drop even further. Conclusion
We don’t see a boom in the demand for entry level twins, just a slow, steady need for new,
glass-cockpit versions as pilots who came up with glass demand them. the Tecnam P2006T is
great for its more demanding handling than the Seminole, it’s a better training tool for turning
out pilots who are prepared for other twins that are vicious if the pilot is careless with speed
control. If it holds up in a training environment and Tecnam establishes a satisfactory service
network, then its significantly lower initial and operating costs will make it a no-brainer for
schools. Otherwise, the Seminole should soldier on as the number one choice for
training programs.