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If Continental Motors ever had any doubts about the aerodiesel market, it erased them in the stroke of a pen with the company’s acquisition of the bankrupt assets of Thielert aircraft Engines GmbH. Despite a rocky ending for Thielert culminating in the jailing of its founder, Thielert (and Diamond) put aircraft diesels on the map during the last decade. And with its own in-house Jet A TD300 and the addition of Thielert, Continental instantly becomes the market volume leader in aircraft diesel.

The Thielert buy gives Continental four diesel products—the 135-HP and 155-HP Centurions, the 230-HP TD300 and the certified but not-yet-produced 350-HP eight cylinder Thielert-developed Centurion. Continental and its Chinese parent, AVIC International, also inherit an installed base of some 1700 engines from a company that has manufactured about 3500 engines in total.

When we recently visited Continental’s factory in Mobile, Alabama, we were told that it intends to integrate the Thielert assets under a common Continental umbrella with unified sales and customer service. The Thielert name will be dropped and the engines will be marketed under the model name Centurion. The main manufacturing plant will remain where it is now, in Lichtenstein, Germany, with service centers to be added all over the world, including the U.S. and China. In Germany, the operating unit will be called Technify GmbH.

In parallel, by mid-summer 2013, Continental was rounding out development on the TD300 and tooling the factory to produce it, although there are no promises on delivery dates. The intro TD300 will get another development round to increase the engine’s critical altitude with an improved turbocharger.

Global View

Continental CEO Rhett Ross is characteristically blunt in describing why the Thielert acquisition made sense: “We have just got to get out from under the U.S. market as the driver for us,” Ross said, chiefly because with no unleaded 100-octane replacement in sight, U.S. market growth is flat and global growth is likely to be nonexistent in gasoline engines. When it announced its own diesel project in 2010, relying on base technology acquired from the France-based SMA, Continental said it wanted multiple solutions to accommodate both a global market and a U.S. market that steadfastly refuses to decide on fuel preferences in a world market that already has: Jet A and mogas.

Continental now has more engines to match more fuel choices than any other manufacturer and across more horsepower ranges, even if some of those choices aren’t yet developmentally mature.

 In Thielert, Continental is getting a proven engine line, albeit one with warts in need of treatment, a healthy installed base, but customer service that some owners have called mediocre at best. On the plus side, customers tell us it has improved in recent years.

Thielert’s relationship with its initial major civil customer, Diamond Aircraft, grew so strained that Diamond CEO Christian Dries started his own company—Austro—to make diesel engines for Diamond airplanes. In addition to Diamond’s initially hot-selling DA42 twin, Thielert made its mark just as the UAV market was emerging and its engines are still found on drones, including the General Atomics Warrior.

That business financed and sustained a modern, state-of-the-art factory in Lichtenstein, Saxony with a typically well-trained European workforce. Profitable though it may be, Continental will lose the General Atomics military business because of security issues related to its Chinese parent.

“That leaves us with a hole we’ll have to fill. We think the civil market is strong enough to do that,” Ross says.

Off to a good start in 2004, Thielert ran into trouble in 2008 after a spate of maintenance issues with its engines gutted its finances because of an over-promised and ill-planned warranty program. Bankruptcy followed, leading eventually to an indictment of company founder Frank Thielert for allegedly systematically deceiving investors about the true value of the company.

In June 2013, a German judge jailed Thielert as a flight risk during his trial and he remains incarcerated. Continental and the industry it serves is well aware of how the Thielert affair tarnished both the company and aerodiesels, thus the new company will be scrubbed of any identification with Thielert. Ross believes the Centurion nameplate wasn’t besmirched by the Thielert name, so it will be retained. The larger issue is that the company has been stewing in bankruptcy since 2008 with developmental energies that are unsurprisingly moribund.

Engine Fixes

Many customers caught in the 2007 and 2008 Thielert meltdown felt stranded by both Thielert and Diamond. Thielert eventually solved some of the Centurion’s shortcomings and, to its credit, it never stopped shipping parts, although it raised prices to what some customers considered usurious levels. The bankruptcy halted development toward higher TBRs and ridding the engine of disruptive gearbox inspections every 300 hours proved an unattainable goal.

When we interviewed Frank Thielert in 2005, a 2400-hour TBR—time between replacement--was promised by 2006, yet seven years later, it remains at 1500 hours for the 135-HP 2.0 engines and 1200 hours for the 155-HP 2.0s engines.

Continental told us getting the TBR to at least 2000 hours and eventually 2400 is a critical first step in its post-acquisition plans. And that push will also include increasing gearbox inspection intervals. Continental told us Thielert has on the shelf an improved gearbox that will immediately allow 600-hour intervals, which was expected to happen shortly after the acquisition. Although it was fielded, Thielert never completed the approvals allowing 600-hour intervals, probably due to the company’s bankruptcy stasis.

Increasing TBRs may be a taller hill to scale, but will be critical to the competitive position of these engines. Our past surveys of owners suggest that thanks to diesel fuel efficiency, even at the lower TBRs and allowing for repetitive gearbox inspections and high replacement costs, the Centurion 2.0 has eked out operating costs equal to or a little less than near-equivalent gasoline engines. Continental thinks the Centurion line is positioned to improve this, if it can reach higher TBRs and improve the gearbox.

Homegrown TD300

As Continental was tending to details on the Centurion purchase, it was also busy completing work on what will be the mid-power option in its diesel line—the 230-HP TD300. In 2009, Continental purchased from SMA the rights to use the SMA SR305 as a technology base for its own diesel. Last December, Continental certified the TD300, which addresses the original engine’s shortcomings, specifically its unnerving tendency to quit when reduced to flight idle—especially in cold weather—and turbocharger limitations that hobble its altitude performance. Actually, as of July, the turbocharger improvements were still in the works, but these are expected to appear when the engine reaches the final production version. Continental declined to mark a calendar date for that, however.

As aerodiesels go, the SMA engine qualifies as a genuine graybeard, having first appeared in the U.S. in 1998.  It’s a four-cycle, four-cylinder engine cooled by air and oil with Bosch-type inline pump injection and minimal electronic intervention. (A limited authority controller provides throttle-by-wire control of the fuel rack.)

Although SMA flogged the SR305 at shows for years, it never did much to promote its engine other than limited STCs for Cessna 182 conversions. Only last summer did SMA finally land an OEM for the engine, Cessna, which is using an improved version of the engine called the SR305-230E in its new JT-A 182.

Given the inherent operational simplicity of diesels, it’s no surprise that Continental came up with similar improvements to its version of the SMA base. Specifically, the engine couldn’t maintain enough combustion heat to remain alight at low power settings and thus had a limitation requiring high throttle settings on approach. That translated into higher approach speeds than are ideal for a Cessna 182.

Continental addressed this with a series of tweaks, according to James Ray, the company’s lead engineer on the project. New pistons increase the compression ratio to 17 to 1 from 15 to 1 and a new intake manifold improves the engine’s breathing. Mechanically, Continental retained the SMA base, but added improved through-case bolts, critical structural components in both versions of the engine. Ray said Continental’s tests indicated the original bolts were suffering from plastic deformation, so it increased the material yield strength and diameter.

One shortcoming remains on Continental’s plate to fix: an improved turbocharger. Although it’s a good, economical performer at low altitude, SMA originally spec’d a turbo that lacked sufficient pressure ratio, so the engine’s critical altitude was essentially sea level and its service ceiling was limited to 12,500 feet—anemic for a turbocharged engine.

In the SR305-230E for Cessna, SMA addressed this with a new turbocharger and Continental plans to do the same, although they’re not there yet. For certification expediency, the version of the TD300 we examined in a Cessna 182 at Mobile in July is designated the B model. But the market introduction version will be the TD300C. It will have an improved turbocharger, a critical altitude of 10,000 feet and a service ceiling of 20,000 feet. In our view, that makes it a considerably more competitive engine.

Continental considers the TD300 mature enough to commit to production and when we visited Mobile, it was doing just that. Assembly cells were being designed and tested in anticipation of a type production certificate.

Continental’s Market Play

In just three years between 2005 and early 2008, Diamond, using Thielert engines that hadn’t yet revealed their foibles, proved a viable diesel market, eventually selling 600 DA42 diesel twins plus 400 diesel DA40 Star models.

Although the market was stronger then than now, even Diamond was surprised by the uptake. The toxic combination of a world recession and Thielert’s bankruptcy tanked diesel sales, but a trickle persisted. Diamond remained confident enough in diesel to launch its own subsidiary, Austro, to build diesel engines for its aircraft.

Continental seems equally bullish on diesel and somewhat wary of the gasoline engine market, at least in the U.S., where a future replacement for 100LL remains unclear. Continental still has a strong market in avgas manufacture and parts and Rhett Ross says it remains committed to sustaining that. The service tail on these engines is too big a business to abandon.

But it also considers itself a global player and for Europe, Asia and Africa, that means diesel. When we asked Continental’s VP for sales, Johnny Doo, for his estimate of diesel market penetration, he said it could be 25 percent by 2018. At current world production rates, that would be about 500 aircraft a year or, if the market expands by a third, as many as 650. We’re not sure if this is realistic or not, but Diamond, on its own, managed to gain about 4 percent marketshare in a mere four years before the economy skidded. It was on track to increase that margin substantially.

With Cessna now in the diesel market, it’s hard to see how Cirrus, Piper and others won’t soon follow and Continental says it will maintain a dual focus on OEM and conversion markets.

The U.S. market for diesel—OEM or conversion—remains uncertain and will be driven by fuel costs and worries about availability. In Europe, Asia and Africa, availability is increasingly the only driver: avgas just isn’t to be found and regardless of what happens in the U.S., 100-octane’s future in the emerging markets seems bleak.

“Emerging market,” by the way, has evolved into a euphemism for one place: China. “The way I see it,” says Continental’s Doo, “the one place that doesn’t have many airplanes today is China. That market may not be tomorrow, but it may not be far away.” It looks like Continental is counting on that and it thinks it now has four engines to fill any conceivable market demand.

A version of this article appears in the September 2013 issue of Aviation Consumer.

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EAA will host a job fair at AirVenture next week, a new opportunity that has drawn a lot of interest both from companies seeking to hire and workers looking for jobs.  AVweb's Mary Grady spoke with staffers at EAA who are organizing the event and with Cirrus Aviation, one of the participants.

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AVweb landed on the World Wide Web in 1995. Since then, we've amassed a huge archive of advice, analysis,and inspiration. Travel back with us for a look at a classic article from AVweb's past.

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It was a weekday evening and I'd just finished flying with a relatively new instrument student who was proving to be competent, determined to learn, and overall a genuine pleasure from an instructor's point of view. I'd stopped into the Pilot's Lounge at the virtual airport out of habit and ran into Old Hack, Sandy and a few other regulars. It was immediately obvious the topic of the day was frustration with the very public, stupid-pilot tricks experienced every year at the EAA's blowout at Oshkosh. In a matter of minutes, I listened to recitations from my friends about everything from trying to follow someone on the Ripon arrival who couldn't hold airspeed or altitude and made things miserable for everyone trying to follow him, through a half-wit on Unicom frequency who had not read the NOTAM for the arrival procedures and wanted someone to read it to him over the air, to watching pilots land the wrong way on the active runway, opposite to the flow of arriving traffic. The annual parade of knuckleheaded behavior by pilots at Oshkosh is a matter of great concern to me, personally, because I fly in and want to do so safely and because some years ago a friend of mine was killed on the Ripon arrival, not too far short of the approach end of Runway 9. I wrote a column about thatand expressed my deep, abiding anger at those who were hurting all of us in GA by their simple lack of basic, common sense in and around airplanes.

Gonna Be a Bad Year

One of the things I've learned in flying into EAA Oshkosh for something on the order of 35 years is that there are good years and bad years for accidents and close calls. One way to predict a bad year for the arrivals (and departures) is if there has been a fuel-price spike. The events are so connected that it's scary: Until prices stabilize and pilots get used to a new high, they tend to cut down on their flying in the months before AirVenture so they can be sure to have enough money in the budget for the trip to Oshkosh. The outcome is as one would expect: Pilot skill levels are down, but because pilots are not good at self-evaluation, the accident rate jumps for the overall process of getting to and from Oshkosh. The Ripon arrival becomes a bad dream of airplanes snaking all over the sky, passing each other and generally demonstrating that their pilots have no business flying in circumstances where there is a heck of a lot of traffic. There almost always seems to be an upsurge in scud-running accidents as pilots fly low in the annual few days of foul weather and hit towers or power lines, or simply fly into the ground when they bury their head in the cockpit to stare at the map or GPS. Sadly, this is a big fuel-price-spike year, the number of cell-phone towers continues to grow, and the new, 400-foot-tall wind generators are multiplying across the landscape so there are more and more things to hit. I'm very, very concerned about the accident rate this year. Even in the good years, we can count on at least one experienced pilot stalling an airplane within a few miles of the airport while trying to follow someone on the Ripon arrival. We can rely on a few of the utterly clueless who have no business flying at all, but insist on doing so, killing themselves and, criminally, taking others with them. I watched one of those folks set up to land on Runway 27, with no other airplane anywhere near him, then stall the airplane while turning from base to final and crash. Well, he did hit the runway -- an angling, glancing blow, sort of in passing -- before he cartwheeled to a stop off to the side.

How Busy?

Bluntly, it is time that we take a cold, hard look at ourselves before we decide to fly into Oshkosh at the end of July. First, let's admit precisely what it is that we propose to do: Fly into the very busiest airport in the world. We are going to fly into the busiest airport in the world. The airport with more traffic than any other airport in the world. In the world. Let that statement lie there in the sun for a moment or two and start to ripen while the significant sinks in. For about a week, Wittman Field at Oshkosh, Wis., is busier than Atlanta Hartsfield or Chicago O'Hare or London Heathrow or LAX. There are a lot of pilots for whom the idea of flying into a controlled airport gives them the willies and they avoid doing so like the plague; they also avoid contact with air traffic controllers. And, guess what? Those same pilots are going to fly into Oshkosh. Operating in and out of the busiest airport in the world is truly big-time aviation and needs to be taken as seriously as the most serious flying we do in our lives. Yet we in GA apparently don't take it seriously enough because each year a bunch of us die flying into or out of that airport. Think for a minute: How many accidents are there involving airplanes going in to or out of O'Hare or Hartsfield in a given week? By and large, none, right? How come we in GA can't match that result in any given year? What's wrong with us?

A Few Symptoms

I certainly don't have all the answers, but I've seen a lot of symptoms of the problem. I've heard the student pilot bragging about how he flew in to EAA Oshkosh as a solo cross-country even though the NOTAM clearly forbids student operations. I've heard some instructors say that such a thing is fine. It's not. It's basic, unmitigated arrogance and stupidity. I've heard the pilots calling Oshkosh Tower 10 miles west for landing instructions. I've watched the guy on downwind insist on flying at 800 feet agl and a mile away from the runway while he complained to the Tower that all those other airplanes were flying too low and too close to the runway. I've watched the Cherokee whose pilot could not seem to slow the airplane down to approach speed and then, when told to land on one of the colored dots on the runway, simply shoved the nose down when he was somewhere in the vicinity of the dot and landed on the nosewheel, lost directional control and wheelbarrowed off the runway. I've listened to the white-faced, recently landed pilot tell about the airplane in front of him who flew the arrival varying his airspeed through about 30 knots and his altitude by a couple of hundred feet each side of desired and then, while still a couple of miles from the runway, suddenly dropped all the flaps and slowed down to 55 knots and powered the airplane all the way to the runway while there was a melee of airplanes behind him trying to avoid over-running him and each other. So, here's the deal: As someone who has had a friend die on the approach to AirVenture, and who wants to fly in safely this year, I propose we make an agreement. Let's agree to print out, study and mark up the NOTAM [Ed. Note:  If you're reading this in the AVweb archive, the previous link is to the 2008 NOTAM, not the current year's!] well before we go so that we will be ready for the arrival procedure no matter which runway is in use. Let's agree to be certain we can hold indicated airspeed within 5 knots of the desired number and altitude within 50 feet either side of the desired height. (For most of us, it's going to be 90 KIAS and 1800 feet msl). If I don't have the NOTAM annotated and sitting where I can grab it as I near Oshkosh or if I can't hold speed and altitude within those limits, I promise I won't fly in. I'm asking the same promise from you. I'm asking ... no, I'm demanding ... that if you have a flight review coming up in the next month or three, take it before you fly into Oshkosh so that your skills are at their best. I've got some recurrent training scheduled, I want to make sure I'm not a hazard to someone else and that I'm as ready as I can be should something go wrong.


The only trouble with the agreement you and I just made is that, from what I've seen over the years, the problem children in aviation don't read. They are not subscribers to aviation publications, they do not read NOTAMs or FAA safety publications or make much effort to keep up with what is going on in aviation. They just get in their airplanes and go, either oblivious to the world or not deigning to recognize other pilots and airplanes. Therefore, this year, let's extend our agreement: Let's agree to be intolerant of the bozos who won't or don't read or keep their skills up and are accidents waiting to happen. Let's see if we can find a way to reach the out-of-touch, the problem children, on our airports. Let's try a two-phase approach to the situation: While it would be nice to give each of the yahoos a Stooge-slap to get their attention, we probably have to be a little more subtle. Let's start by creating a rumor that will get their undivided attention: A $100 landing fee has been imposed at AirVenture, and that the fee is waived if the pilot can produce a copy of the NOTAM in either paper or electronic form after landing. It's not true, although I fervently wish it were, as hitting pilots in their wallets is the fastest way to get their attention. However, the problem children don't do their aviation homework, so they will have no way of knowing the rumor is untrue. Therefore, if we let it start, it is going to cause some pilots who otherwise wouldn't get the NOTAM to do so. What the heck ... this rumor might just save a life or six. The next step is to print out this column, or the earlier one I wrote, write appropriate, helpful, friendly recommendations on it, and tape it (use the kind that won't mess up the paint) to the airplanes of the folks at your airport who are the problem children. You know who they are. Maybe, just maybe, they'll take going to Oshkosh seriously and do a little preparation. Also, post this on the bulletin board at your FBO where some folks might read it.

Here's the Deal

So, to recount the deal we're making with anyone who wants to attend AirVenture this year, fly in and not get dead in the process or create more newspaper headlines and TV news stories about the nuts in the little airplanes that kill themselves at the biggest aviation event in the world:

  • First, we'll get the NOTAM, read it, mark it up and have it with us in the airplane on the way;
  • Second, we'll make sure we can fly at the required indicated airspeeds and altitudes;
  • Third, we'll be considerate of others; because we know there are a heck of a lot of airplanes out there and a little consideration goes a long way ... we don't need road rage in the sky. I'd like to think that pilots are a cut above the ground-bound;
  • Fourth, we will be willing to postpone or cancel the trip if the weather isn't good VFR (and we are not on an instrument clearance), the airplane isn't working quite right or we are physically under the weather;
  • Fifth, we know that the airplane will not fly over-gross just because it's going to aviation Mecca. I'm convinced a few of the stall-spin accidents on the approach to Oshkosh over the years were because the airplane was loaded aft of the aft cg-limit and when things got ugly, the pilot was dealing with a neutrally or negatively stable airplane and couldn't get things collected before stalling it while trying to maneuver in traffic;
  • Sixth, we'll agree to fly a tight, low pattern, at appropriate speed and fly final at 1.3 Vso and then land within about 50 feet of a target on the runway without wild gyrations. Oh, and when we land, we'll turn off the runway into the grass right away, because we know we're supposed to do so and the grass is smooth. Then we'll hold the yoke or stick all the way aft when taxiing on grass because we want all the prop clearance we can get. And we know that failing to do so brands us as rubes in the eyes of all those pilots sitting and watching airplanes; and
  • We'll also agree to carefully read and follow the departure procedure, especially noting and complying with altitudes and headings to fly and when to turn on the transponder, and we'll keep our heads swiveling, looking for and avoiding other airplanes.

This year, let's agree to stay alive so we can truly enjoy AirVenture and all that it has to offer, so that we can return to our homes with stories of very cool things we saw and did, but without having seen things that will become stupid-pilot tales. Let's agree that, if there is going to be something about us and aviation and AirVenture in the newspaper or on the TV news, it is going to be because we are a positive influence on aviation and helped make it a little bit better for everyone concerned. See you next month.

Want to read more from Rick Durden? Check out the rest of his columns.
You'll notice that Rick's classic column, written back in 2008, references that year's arrival NOTAM. For your reference, here's a link to this year's (PDF). Read More
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Continental’s purchase this week of the assets of Thielert Aircraft Engine GmbH didn’t exactly come out of left field. Continental already declared its interest in diesel in 2010, when it announced the TD300 diesel. And that was before China-based AVIC International came into the picture with a necessarily global view, but not one that Continental hadn’t already adopted.

The question is, does the purchase make sense? Is it a natural fit? It’s hard to argue otherwise if you believe diesel propulsion is the coming thing in light general aviation. It’s delusional to look out toward the marketing horizon and conclude that 100-octane avgas is going to spontaneously come roaring back into the market as a forceful player or that mogas will suddenly bloom as a major factor. So that leaves Jet A, the world fuel of choice, some form of which is available everywhere.

Both Lycoming and Continental became vocal about this three years ago and in return, the FAA and industry gave us a plodding, cumbersome regulatory framework to certify a new aviation gasoline to a timeline that’s uncertain enough to barely sustain itself, much less ignite growth. Faced with this, Continental voted with its dollars and started the investment in diesel. I suspect we’ll see something from Lycoming before long; the trend is just unavoidable.

In my view, Continental’s Thielert purchase is about as vivid an example of a company making its own reality as I’ve seen in awhile. Overnight, Continental has a market-dominating product line in the traditional three power ranges—about 150-hp, 230-hp and 350-hp. Despite Thielert’s stumbles, the lower horsepower variants are largely proven, with some 1800 or so flying. There are some issues with them, which Continental knows it has to fix. Specifically, the TBRs are too short and owners are still stuck with the nuisance of replacing a gearbox every 300 hours.

The 230-hp TD300, which Continental developed from the SMA SR305 base, hasn’t been fielded in large numbers. From what I’ve seen of its performance and durability, it looks promising. The 350-hp Centurion 4.0 that Thielert developed and certified is an unknown and it may take some millions to find out what it has. STCs exist for the Cirrus SR22 and Cessna 206, so there may be a nascent retrofit market. But Continental has no small risk in proving that engine realistically marketable.

With avgas at $6 to $7 in the U.S., you’d think that diesel would have flowered more than it has. But Diamond never pushed its diesel aircraft in the U.S. because it felt the service network wasn’t in place—they were right—and Thielert’s flawed business plan caused the diesel revolution Diamond started to fizzle even before the world economic downturn damaged it more. Further, in the U.S., we don’t resonate with diesel the way buyers do in Europe.

My gut feel is that the world pendulum is swinging back and Continental’s timing may be perfect, if not a little early. Uncertainty over avgas may push things along toward diesel faster than some of us think. We have no idea what Continental paid for the Thielert assets so a value assessment on the purchase is difficult to make. But it’s fair to say that in Thielert, Continental will have a sound technical foundation upon which to build potential diesel market dominance.

Thielert tanked because it got the engine economics wrong. It assumed the engines would need longer to prove than they did and its cradle-to-grave warranty coverage was unsustainable. It probably underestimated production costs, too. You can readily see how some tweaking turns the whole thing around.

For six years, I’ve been following Stan Fetter’s diesel conversions in a pair of Cessna 172s, which he uses in a traffic reporting business in the Washington, D.C. area. He’s been through all the typical Thielert travails and then some. His conversions cost about $50,000 for the engines and $60,000, all in. Initial TBRs on those engines was 1200 hours or so for the engine alone. That’s $42 an hour. Fuel, at 4 GPH, was another $23 or so. But the engine required a $3250 gearbox every 300 hours, so that brought the total hourly on paper closer to $75. (This doesn’t include the one-time conversion cost.) Although he couldn’t dodge the gearbox requirement, Fetter did extend past the stated TBR, knocking that $42 back some.

Compare that to the Lycoming the Thielert replaced. With new cylinders, overhauls on the O-320 cost about $20,000 or $10 per hour for the engine and another $48 for fuel. But Fetter found that magneto maintenance and cylinder replacements nudged the Lycoming’s hourly a bit higher and the diesels had better dispatch reliability. But at the stated TBR, the diesels still had higher operating cost or, at best, parity with the Lycomings. (There are other replaceables on the way to TBR, but I'm brushing past them here.)

But look what happens when the gearbox inspection is eliminated and the engine’s TBR is increased to 2400 hours, which Fetter thinks is doable because he ran one to 2600 hours. Continental hasn’t given us engine prices yet, so I’m using about $50,000; what Fetter paid. Then the hourly for the base engine drops to $21 and with fuel, the total engine operating costs are something like $45, exclusive of airframe maintenance. It looks better yet if the engine can reach a 3000-hour TBR and/or Continental can reduce the cost of the TBR, say by developing a less expensive overhaul program. 

But to be blunt about it, U.S. economics don’t matter much here: global ones do. If you plug European fuel prices into the cost model, the numbers show a larger Delta. Even using mogas in Europe, fuel costs for a 172 are $68 to $75 an hour, versus $41 for the diesel. That’s real money and over the life of an engine, it will pay for the diesel with a nice surplus to defray other costs.

By the way, Continental’s estimate for a Cessna 172 conversion is about $56,000 for the engine and hardware and another 160 to 180 hours of labor. Call that around $70,000 all in, 16 percent more than Stan Fetter paid six years ago. Those initial numbers might shift some.

While these developments won’t usher in the age of dirt cheap flying, if Continental sweetens up TBR and eliminates the gearbox replacements, it at least takes operational costs in a positive direction—downward--which can only encourage market expansion, or whatever passes for that these days. Moreover, Continental is injecting a pulse of energy into the moribund state of Thielert—capital, engineering focus, developmental determination, customer service and market sense. The more of that these engines get and the more they fly, the better they are likely to get.

My numbers are based on historical data, but if the company stays in range of those numbers, the economics work but, more important, the directionality is encouraging. And that’s why Continental’s big initial push will be longer TBRs and life-of-engine gearboxes. Even so, it’s important to understand that diesels are not going to suddenly show us half-price flying. What they will do is reduce costs measurably and reduce worries about fuel availability; more on the global field, less in the U.S. 

While I’m convinced that we’re on the cusp of wider diesel acceptance, I think Continental is gearing up for what will be a long game on a global pitch. My guess is we’ll see a steady, robust ramp up in diesel and if that’s true, Continental will be well positioned to profit from it.

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