Diamond’s diesel-powered DA40 NG is proving a popular choice for flight schools. In this video, AVweb’s Paul Bertorelli explains the engine’s details and gives the airplane a wring out in snowy London, Ontario.

8 COMMENTS

  1. Very interesting presentation Paul.
    2 items I question.
    1 – 23,000 psi for the injector pump. Are you sure of that?
    2 – Your copilot mentioned that BOTH ECU are running ALL the time, but also says
    that if one fails, the other will switch over. Switch over? if running all the time?
    Like mags.

    I’ve not been current with my power plant rating after rebuilding engines since
    1959, but after numerous overhauls, I had not heard of the TBR you mentioned.
    Is there now an hour limitation for the TBR?
    Thanks – Bob

    • Bob, My understanding is that those very high pressures result in super fine atomizing of the fuel and super precise timing of that injection into each cylinder. The pumps and injectors are out of this world. When combined with turbo charging, current diesels are getting more power per swept volume than a good gas engine was 20 years ago. And more torque than a V8 Chevy. Impressive stuff compared to the Toyota 2h diesels I am more familiar with.

  2. Thanks for the reply Paul,
    All the diesels I had worked on had injector pump distribution tubes to each injector (as you probably know) – that’s why I was unaware of a “rail”.
    I copied this from a Yanmar manual.

    injector pump pressure on yanmar 2GM20FC
    The 2GM injector opening pressure is 170 kg/cm2 ….plus /minus 5. Thats between 2347 PSI to 2489 PSI.

  3. Bob,
    Your aviation background shines through in your comments. The ‘Distributor Pump’ technology you seem familiar with phased out of use in automotive applications about 15 or 20 years ago. In aviation terms that isn’t a long time, but in automotive terms that is generations of technological advance. In fact the 23,000 psi capable fuel pump on the Austro engine isn’t even the latest generation of ‘Common Rail’ technology. They wisely selected an older more proven and robust design, many automotive diesels are now capable of 32,000 psi injection pressure.

    As I sit here under my government mandated shelter at home order, your comment really has gotten me thinking about how the aviation and automotive sectors have struggled under the hand of government in their own separate ways. The regulations covering certification of aircraft and automotive engines are similar in their depth and complexity.

    Both are built on foundations of safety. In the aircraft world it has stifled innovation by making it too costly. In the automotive world it has demanded innovation at any cost. With an emphasis on improving air quality for the “safety” of it citizens, the California Air Resources Board has a long history of setting limits that are out of the reach of current technology and tasking industry to go make it happen. In fact there isn’t an automotive diesel engine sold in California today that can meet every one of the minutia of requirements written into the regulations. Every manufacturer pays a fine to CARB for every diesel engine sold.

    The end results of the efforts of these Dr. Jekyll and Mr. Hyde divisions of government are similar. The cost of airplanes are out of reach for most common people, and to an increasing extent so are the cost of a nice diesel pickup. But at least the pickups are a heck of a lot nicer than they were 20 years ago, accompanied with a 96% reduction in emissions.

  4. Paul: Love your stuff. You talked relatively little about the flying characteristics, other than you like them. What do you think about the increase in stall speed? Even though flight schools are using the NG, the higher stall speed seems a step backward for safety and flying characteristics. Would you expect the same best in class safety stats for the NG? If I can’t afford an SR22, should it be at the top of the typical owner pilot list?