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News of May 06, 2007

Diesel engines at Sun n Fun 2007: The time is for when, no more for if.

At Sun n Fun this year, one could visit Diamond Air and see the DA 42; Superior engines and see the Centurion V8; SMA and discuss progress of various STCs other than the 182; Epic Aviation and hear their latest proposals for the 172 Thielert conversion; DeltaHawk and hear that they are doing well indeed thanks to the DoD Drone market using their 2-stroke 4-cyl. Diesel. Answering one accusation from a subscriber, i. e. that DieselAir seems to favor European diesel firms against good old US engineering, will be the occasion for a general discussion of competition on the US market today.
Competition in aero diesels is dominated for the time being by Thielert (over 400 engines flying now) with their Centurion family entrusted to their recent acquisition Superior Engines. No, once again, the Thielert engines are not automobile engines converted to aircraft use. Their 4 cylinder 135 HP uses an engine block from the Mercedes-Benz production, that’s all. Their V8 310-350 HP has lost any commonality with automobile. Thielert chose the liquid cooled, in-line, geared engine against the direct drive, air cooled, opposite cylinders engine. In 1918, same wise, a Liberty engine and a Gnome rotary engine; or, in 1940 a Rolls Royce Merlin engine and a Wright Cyclone engine; illustrated the same difference in choices. The pros and the cons are as old as aviation. The Thielert is OEM on the Diamond DA42 and, in Europe, on the Diamond DA 40 and the Robin DR400 (France). Epic Aviation offers conversions on 172s now. Cirrus just announced that the SR22 is available now with the Thielert V8 as OEM.
SMA is second and far behind in terms of numbers of engine actually flying in the world (around 40-45). The SMA is a 230 HP, 4 cylinder O engine looking like a smaller O-320 surrounded by huge heat exchangers. It is oil and air cooled. The propeller is on the crankshaft, following the second alternative. It has much less moving parts than a Thielert. It is STCd on the 182, and will be at the end of the year OEM equipment on the Maule MX9. Maule has a backlog of 9 orders and has 5 diesel planes in the shop. Tule River Aero on the West Coast (www.tuleriveraero.com) and FlyJetA (www.flyjeta.com) on the East Coast are offering conversions. DACI in Atlanta (http://www.dieselairplanes.com) is taking orders for fully converted and refurbished 182 SMAs.
DeltaHawk is third, but the one to watch because, if I am well informed, thanks to the DoD market they are cash flow positive. SMA is certainly not. Thielert is too, but with a huge investment to amortize. The DeltaHawk is a 160 HP 2-stroke V4, and has the least moving parts of the three competing designs. It is not yet certified and even less STCd.
Who is going to win? In my opinion, all of them; and if anyone fails it will be bad news for the others because it will reflect on the diesel concept which is still shaky in US pilots minds. Here is why.
Any US pilot dislikes the Thielert design because it is geared. Old argument: If the prop hits something hard, the one tooth in the gear transmission takes the shock hard enough to risk damaging the engine. Thielert answers: Our engine combines a vibration dampener plus a friction clutch limiting maximal torque, so this cannot happen. Correct. However, gear plus dampener plus clutch adds weight. To what extent? My impression is that it handicaps a smaller 4 cylinder, but the handicap becomes negligible on a larger V8 which is smoother and smaller per HP in the first place. I expect the 172 Thielert to be accepted by flight academies, and the V8 to penetrate first the market of twin conversions: Cessna 400 series to begin with. Thielert Centurion should remain the leader.
The SMA design looks more familiar and your basic US pilot likes it. It is the only 230HP fully certified and STCd on one airplane model which is widespread in the US: The 182. It will take some time before Thielert has something to offer in that power, during which SMA can carve a niche, to be followed with the future 270HP and 300HP of their basic design. There will be competition with Thielert, but not head-on.
DeltaHawk is a wild card. I think that 2-stroke diesel is at least the future for smaller single engines and for experimentals in the 120-200 HP range because of its weight advantage. It remains to be seen that its TBO will be comparable to 4-stroke. Then, it may well end up demonstrating an advantage in operating cost and in weight per HP.
And now, why is the arena dominated by foreign firms and what are Continental and Lycoming doing, considering that as market leaders they had the advantage and the vocation to introduce aerodiesel first?
American engineering is excellent, especially in General Aviation where the US has the advantage of the biggest and most diversified industry in the world. Continental and Lycoming could have hired the right resources to put on time the best diesel on the market. They didn’t because of one factor: Through their publicly traded parent corporations, conglomerates Teledyne and Textron, they are governed by stock-optionism, the most dangerous disease threatening free enterprise today. To maintain stock price as high as possible right now, the only strategy is treating these two old, mature, market dominant firms as cash cows. Keep fixed costs low (research is fixed costs.) Farm out manufacturing (manufacturing is fixed costs). Defend existing designs against any new design (defending old products doesn’t cost much and is low risk.) Until DeltaHawk or even SMA or Thielert have made visible inroads that begins threatening the cash cow. Then, acquire one of them and amortize goodwill. Meanwhile, think about this: With stock-optionism, Curtiss-Wright (now gone), Lockheed, Boeing, Douglas (now Boeing), McDonnell (now Boeing), Northrop (now Grumman), Sikorsky and other great names would never have been born… For the same reason, it had to be Cirrus, a new venture, and Diamond, a foreign firm that introduced the new generation of composite fixed-gear airplanes. Cessna could not do it, and yet they have the resources.
Andre Teissier-duCros

posted at 12:28 PM

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Mission Statement

Every month: news, facts, and comments on the coming revolution for piston-engines aircrafts between 130 and 400 HP: Retrofitting a diesel engine to run on Jetfuel or Kerosene, reduce Gallons/Hour by some 30%, eliminate ignition systems (magnetos, spark plugs) and their problems, eliminate mixture control, increase TBO to 2,400-3,000 hours, increase performance between 6,000 and 12,500 ft., and drastically reduce Operating Costs.

The letter is intended for piston engines aircraft owners, manufacturers, fleet operators and FBOs, re-manufacturers of engines for these aircrafts, manufacturers of engine components and ancillaries, and all professionals acting in decisions of engine exchange or refitting at TBO, in North and South America, Pacific Rim, African continent, and all parts of the world were Avgas, Mogas, Kerosene and Jetfuel are available.

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