Creating the optimal aircraft for the market is one of the most daunting tasks engineers face.
Because it’s always surrounded by risks, what if the market wants a product that does not fit into
the traditional framework? What if the wishes of customers contradict the capabilities of
technology? It is necessary to strike a balance between opportunities and the price that you
will have to pay for them, and today's legend; the Cirrus SR-22, is a serious game of balance.
In 2022, Cirrus had already been the industry leader for two decades,
building most of the world’s GA products. Since the SR22 was introduced, about 7000
of the four-place singles has been built, and it's already the world’s most popular airplane.
But the title of No. 1 comes with serious obligations,
and serious continuous innovation is one. A lot of new features have been added to the SR22,
but how much has innovation changed the plane since its introduction? You might argue that
the newest SR22 is a lot better than the early model by quoting that after the original SR22,
the G2 featured a redesigned cowl, a new prop, a spiffed-up interior, an improved door
latch design, and a six-point engine mount that addressed vibration issues in the early models.
Then the SR22 Turbo featured a turbo-normalizing upgrade kit, built-in oxygen, and so on.
The G3 model featured a redesigned wing and carbon fiber spar, followed by the SR22T in 2010,
which featured a turbocharged engine. The G5 in 2013, brought optional tri-color paintwork,
better flap extension speed, beefed up the main spar, strengthened the landing gear, and
extra layers of composite to the airframe. Then the G6 came along with Bluetooth connectivity,
keyless entry, better lights, and faster avionics. No doubt, Cirrus has greatly improved the product,
but most aviation enthusiasts will never agree with this,
because the truth is, the term "visionary" is the most misused word in general aviation today,
and it’s like this because bureaucracies in aviation have grown so strong that
adding Bluetooth and keyless entry to a small plane is considered "revolutionary." Even the
smallest alteration has become newsworthy. But is it the aircraft manufacturer’s fault?
Some aviation enthusiasts may never understand why aircraft designers and manufacturers
hardly improve their basic designs by any significant margins.
So, what is my problem with the SR22? The Engine. Before you can fully understand
my problem with it, let’s understand it. The SR22 is powered by a 310-HP Continental IO-550
engine, which is one of Continental’s best power plants. The IO-550 engine is durable and
highly economical only when compared to its fellow dinosaurs, because when compared to newer engines,
especially ones in Diamond airplanes, your guess is as good as mine.
Engine management is simpler. It features a two-lever control;
the throttle and mixture lever. The prop is taken care of automatically. Most owners seem to like
this arrangement, but for those accustomed to three levers, it takes some getting used to.
To fly the maximum range at 75% power, you cannot fill up the seats. The SR22 will blister along at
170 to 180 knots at about 18 GPH rich of peak. However, given the reality of avgas prices,
not many owners will run the airplanes that way. Also, given the reality of airplane ownership,
anyone that can afford these machines is not qualified to complain about fuel prices.
Throttling back to 65% on the lean side gives about 15 GPH and 172 knots.
You can easily push that up to 80 percent power at 17 GPH and recover some of the lost speed. This
appears to be where most owners operate the SR22, as the IO-550 is smooth and perfectly happy in
this regime and will run even leaner for max-range cruises. The service ceiling is 17,500 feet, with
a rate of climb of 1,270 feet/min and a maximum range of 1,169 nautical miles at 55% power.
These numbers might sound impressive, but has anyone ever thought that the SR22
with the Continental IO550 is like a baby with the heart of an 85-year-old person?
Like many others, the Continental engine in the SR-22 is seriously behind in the
technology of fuel and ignition control. Most aviators want something better, something with
single lever control, burning diesel, and easier management. But is it as simple as that? No,
It’s pretty hard to move away from something everyone knows its strengths and weaknesses,
what they cost, how they perform, and how reliable they're likely to be. But is it totally all about
the customers or entirely for lack of trying by manufacturers? Well, I think it’s safe to say it’s
a lack of trying by manufacturers because before Cirrus introduced the glass panel,
they carried out a survey and customers reported that they highly trusted the analog instruments
and didn’t wish to switch, but when Cirrus introduced the glass cockpit anyway, buyers rushed
to it. This is to say that most customers don’t really know what they want until they see it.
But the concept of ditching these grandpa engines isn’t really a new idea.
Diamond aircraft have done it. It wasn’t easy at the beginning,
but today, their planes are the most sorted out and most refined in general aviation today.
To better understand how they did it, let’s go back a little.
The project started off with the Thielert Centurion 4.0, the same V8 Mercedes diesel
engine used in the S-Class. Cirrus wanted to try the engine on the SR22,
but when they realized the cost of re-engineering the plane for the higher gross weight,
they abandoned the project because there is no serious gain in performance to justify the costs.
But won't the Thielert Centurion have improved the SR22 anyway? There are some trade-offs for
sure. For example, the Thielert Centurion is 300 pounds heavier than the Continental IO-550,
which takes a toll on the power-to-weight ratio, but it by far makes up for that
in fuel efficiency. For example, at 70% power, the centurion burns 11 gallons per hour,
compared to the 14 gallons lean of peak in the continental. And the best part is that,
for the equivalent weight of fuel, the diesel gives you more range. Going a little deeper,
we’ll realize that diesel is a little cheaper than avgas, and you can get diesel everywhere, unlike
avgas, which is not always readily available in a good number of airports outside the U.S.
The Centurion is much easier to operate. You want to start it up? Just hit the startup
button. You want to accelerate? Just push the throttle forward. The single lever control is
the sweet spot of the operation, no knobs or levers for mixture and prop. If it's a cold day;
simply turn on the glow plugs for some seconds and your engine is running. If one engine
stalls mid-air, just flip the switch, and it feeders itself. Everything is easy and simple.
Cirrus made the SR22 a little easier too by introducing an automatic prop control.
You never have to worry about it, but everything else is as 1950 as possible.
Starting up the IO-550 is a different story. You have to prime it, get the mixture set,
push the throttle a little and crank it, it might fire up right away, but if it doesn’t,
you’ll be doing that again. If the engine is warm, you have to keep the throttle
wide open. When it's really cold, you need a furnace to heat it up for 15 minutes.
Mind you, this is not a diesel vs avgas argument. It's all about ease of operation,
reducing the pilot’s workload, improving safety, and better engine management. There are some
seriously modernized avgasburning engines out there, like the FADEC-controlled Lycoming iE2.
Previously used in the Lancair Evolution, before they closed down and left the U.S.,
Tecnam is currently using this engine in the P2012 traveller. The iE2 brings the traditional
aircraft piston engine into the 21st century with computer-controlled electronic fuel injection,
electronic ignition, and electronic engine self-protection. Power management
is simple with one lever controlling the percentage of power desired, prop pitch,
and fuel flow. The engine will always determine the most efficient combination of fuel mixture,
ignition timing, turbo boost, and propeller RPM for the flight condition you request.
It will do that while determining optimum settings without hazardous fuel mixtures or ignition timing
and will avoid overheating or detonation without pilot intervention
or the need to monitor the factors that cause these conditions. I wish it burned diesel.
If you feel that the SR22's sales won't decline because of the engine, remember
that great planes have failed for not-so-necessary reasons; the Cessna TTX, the Mooney Acclaim Ultra.
Most likely, Cessna thought that real pilots wouldn’t need parachutes, so they didn’t bother
adding one to the TTX after taking over from Columbia, and they paid dearly for it. Similarly,
some people will think that real pilots don’t need FADEC, lol. But time will tell. I understand that
Cirrus is trying to strike a balance between modern engineering, aesthetics, and safety,
but a million-dollar plane with 50-year old engine technology? Please cut me a break.
The reason buyers are still flocking to Cirrus is that there is no alternative in the market. The
Lancair Evolution piston with a FADEC-controlled Lycoming engine beats the SR22 hands down,
but not a lot of pilots want to go experimental. Textron just bought Pipistrel, which means that
the Panthera will most likely be on the market soon. Let's see what Textron does with the design.
In summary, the SR22 is the most beautiful four-seater on the market right now.
It might be easy to argue that the Pipistrel Panthera is more appealing, and the designs
from Diamond Aircraft are great too. But then, the SR22’s appeal has beaten the test of time.
The Lamborghini-style doors are one of my favorite things about this airplane.
They are not trouble-free, and closing them is not particularly the easiest thing to do,
especially in the early models, but they are certainly the coolest. The SR20 and SR22,
in their various iterations, are hot sellers and good performers. They perform well and generally
deliver on the claim of being easy to fly for low-time pilots. The best thing is that they offer
the right combination of cutting-edge equipment and construction methods without becoming quirky.
If you are in the market for the SR22, the good news for buyers who can’t
afford the eye-popping price of a brand-new Cirrus is that for as little as $250,000,
you can get one of the early models. The best buys are the 2002 to 2004 models with Avidyne avionics,
particularly an early G2 model for well under $300,000. The 2001 to 2003 SR22s are even
cheaper. These likely won’t be all-glass models, as many have steam gauges with an Avidyne MFD.
The interiors of these first-generation SR22s were never a high point, and many of
these older models have tired seats and carpets. In conclusion, Cirrus has changed the nature of
light general aviation over the past decade with a host of innovative features and other approaches.
Over time, it became the best-selling single-engine airplane in the world,
largely because of its innovative blend of excellent features, including a remarkably
roomy cockpit, advanced avionics for its time, and its impressive performance.