Zoche Diesel Aircraft Engine Design

Zoche diesel enginesThe two-cylinder Z0-01A will provide light aircraft with 70 horsepower, light weight and good fuel economy.

Aircraft Diesel Piston Engine Options

zoche aero diesels.jpg

The Zoche Diesel: Like the little red train in the children’s story that makes it to the mountain top first despite ridicule by the bigger, supposedly more powerful trains, the Zoche radial diesel aircraft engine may soon be huffing and puffing its way past its traditional aviation engine competitors.

Zoche has recently announced that its line of lightweight, fuel-efficient, two-stroke, radial diesel powerplants have made it to the production phase.

Design Persistence Pays

But it has been an uphill climb. Designed and developed by Michael Zoche and company in Munchen Germany, the Zoche Aero Diesel has been much belittled by advocates of traditional gasoline-fueled aircraft piston engines.

The engine was theoretically so far ahead of its competition that cynics wrote the effort off as just another fantasy engine. But who could blame them?

8 cylinder aero diesel

The eight-cylinder, two-stroke Zoche Z0-02A diesel is the largest of the Zoche engine line and will be the first to fly in a Westinghouse airship.

This was an era when other wonder engines were bursting on the aviation scene with much fanfare but just as quickly disappearing — never making the transition from design drawings to working hardware.

Just a few years ago there was even a persistent rumor that the Zoche Diesel engine had encountered insurmountable technical problems forcing the Zoche family to begin again with a variant design. The common thought was that the Zoche bubble had finally burst.

The four-cylinder Zoche Aero Diesel Z0-03A will weigh 185 pounds and put out 150 hp, according to the company.

But the Zoches pressed on with dogged determination and no small amount of technical expertise and creativity. In recent years, the number of Zoche engine models increased from two to three, and within the sport aviation community the interest in the project did not wane.

Now, at long last, the incredible Zoche Diesel engine is in production (1995). The most complex engine of the three, the eight-cylinder Model Z0-02A, using quantity production components, was first run during the week of January 16 – 1995.

The Zoche Diesel Specifics

In addition to the models already developed— the 300-hp Z0-02A and the 150-hp, four-cylinder Z0-03A—the Zoches have recently added a 70-hp, two-cylinder ZO-01A. These power ratings are constant to 9000 feet, according to the company.

All three models are direct-drive, boosted, air-cooled, two-stroke, radial diesels, and the specifications for the group of powerplants reveal them to be extremely powerful for their weight and size.

Turbo charging diesel engine

The Zoche Diesel engines are apparently also very efficient. Their rated specific fuel consumption — 0.356 lb./hp/hour — is 25% lower than current aircraft engines.

Thus operating costs will be relatively low. Being able to burn cheap fuel will also help keep fuel costs down. This exceptionally high efficiency also contributes to the reduction of the amount of rejected heat and the parallel requirement for cooling air.

These numbers project the Zoche Diesel engines as being far superior to their contemporaries in every category. According to Zoche, engine prices will be competitive with current certificated aircraft engines.

Zoche Diesel – A Bright Future

In spite of the apparent leap frogging of powerplant state-of-the-art, the Zoche’s have placed great emphasis on reducing the parts count to simplify manufacturing and improve reliability. The initial TBO is projected at 2000 hours. If the Zoche engines perform as planned, they will be well received by pilots.

The engines use just a single power lever—there is no mixture control, no alternate air, no mag switch, no mandatory temperature, no boost or power restrictions and no threat of carburetor ice or vapor lock. A fully automatic pre-lubrication system makes cold-weather starts a breeze.

Zoche diesel engine range

Also contributing to a pleasant flying environment is the relative quietness of the engine. In addition to accurate balancing, torque vibration is minimized because there is only one power pulse per revolution.

Also, the boost system incorporates a turbocharger that reduces exhaust noise. The Zoche Diesel eight-cylinder Z0-02A is slated to have its first flight in a Westinghouse airship later this year.

Zoche diesel radial engine

The same engine will make its first fixed-wing flight in a Extra 300 late in 1995. Availability of Zoche engines, as well as European certification to JAR-E and U.S. certification to FAR 33, is expected later this year.

Like the little train in the story, the Zoche Diesel engines are proof positive that significant obstacles can be over-come with a lot of hard work and more than a little confidence.

Zoche diesel aircraft engine

Figure 1
Power-to-Weight Comparison
Engine Model Power (hp) Weight (lb.)
Z0-02A 300 271
Cont. TS10-520 310 490
Z0-01A 150 185
Lyc. 0-320 150 280
Z0-03A 70 121
Cont. 0-200 100 245
Notes: All Zoche power numbers are constant to 9000 feet; All weights are for similarly equipped engines.

Figure 2
Engine-Size Comparison
Engine Model Length (inches) Width (inches) Height (inches)
Z0-02A 36.8 25.4 25.4
Cont. TS10-520 42.6 42.5 33.5
Z0-01A 32.4 21.8 21.8
Lyc. 0-320 29.6 32.2 23.0
Z0-03A 29.5 21.8 15.9
Cont. 0-200 28.5 31.5 23.2
Notes: All Zoche power numbers are constant to 9000 feet; All weights are for similarly equipped engines.
Zoche Diesel Aircraft Engine Design
Article Name
Zoche Diesel Aircraft Engine Design
It's easy enough to say, lets put a diesel in an aircraft - the truth behind two stroke aero diesels is different. Zoche Diesel engines tackle the challenge

2 Comments on "Zoche Diesel Aircraft Engine Design"

  1. Hi,


    Israel H. Ha

    • Unfortunately the engine is not currently available to the public. The status of the company is also unknown.

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