Has Diamond Built a Better Mousetrap?
Multi-engine piston aircraft have become a relic of the past. Simply put, the need for two engines to enhance safety margins and increase performance is generally outweighed by the (significant) increase in fuel-burn and maintenance costs. Modern piston engines are just more reliable than they were in the 70’s through the 90’s when multi-engines became popular.
However, for the crack-team over at Diamond Aircraft, these facts didn’t get in the way of launching the DA-62 in 2015. Diamond believes that with the right combination of efficiency, price, and load capacity the light-piston-twin will live again.
Their Secret Smells Like Kerosene
For those familiar with aircraft specifications (read: avgeek, like me!), you may find yourself second-guessing the fuel burn Diamond has published for their high-speed cruise setting: 17.1 gallons per hour COMBINED. As a reference point, both the Piper Seneca and Beechcraft Baron consume more than double that with weaker overall performance. How does Diamond do it? Diesel. The DA-62 is powered by two Austro AE330 diesel engines that were modified designs from Mercedes-Benz automotive engines. The end result is an engine design that is more modern, efficient, and simpler to operate than any of its piston competition.
A unique byproduct of the diesel engine is the much quieter operation compared to a traditional piston. This may not sound like much, but the constant abuse from a piston engine is actually a major factor in pilot and passenger fatigue. To mitigate the vibration even further the engines are mounted on an oil-based suspension system. The result is an engine so smooth and quiet I genuinely had to look out the window to see if the motor had actually started; for all the pilot readers - you will have a strong appreciation for the FADEC controlled startup procedure which entails a couple switches and a button. I could talk engines all day, but let’s talk about the important part - interior.
Function Meets Fashion - DA-62 Interior
General aviation is all about trade-offs. You can’t have long range with heavy payload, or speed with fuel efficiency. So with all this function is it too much to ask to also have some fashion and comfort? Apparently not, the DA-62 is built to be a comfortable hauler. Generally, I would equate the interior to that of a luxury SUV, let’s call it a European luxury SUV - since this is an Austrian airplane, after all. The cabin is divided into 3 rows. The most forward row houses the pilot and co-pilot seats that are accessed via a dedicated door. The flight deck is appointed in a minimalist fashion with the venerable G1000NXi taking up most of the real estate. The middle row is the main attraction. It is arranged as a three abreast bench that is about the same width as a Suburban, so while three average adults would sit comfortably it may feel crowded on an all day journey. Legroom and headroom feel adequate for all occupants. The third row has about the same functionality as a midsize SUV, it is really for built for a couple kids or small adults, certainly not ideal for the average guy, but it would work in a pinch (or perfect for easy-going friends). So all-in we’re counting 7 seats on the DA-62.
I earlier referenced the range vs. payload conundrum. The DA-62 is one of the most competitive payload carriers in its class. Full fuel tanks will keep a healthy 1,000 lbs of capacity for stuff and people. That lets you carry 5 NBAA’s standard adults at 200 lbs each over (a highly respectable) 1,000 miles. Sacrifice some of that range and you can fill up the DA-62 to the brim.
A Twin Finally Worth Considering
The Diamond DA-62 is an enigma in a world of fuel-hungry poor performing light-twins. Frankly, it is difficult to find many faults in the design or construction. The Austro engines are a huge win, with fuel economy rivaling high performance singles, the interior was well crafted and presents an option for a true 7 passenger hauler. And the bow on top? This marvel of engineering is built by Diamond - a leader in safety and innovation.
Now, there is one shock that many of you know is coming, PRICE. As of this posting, an average build for the DA-62 lands you just north of $1.2 million (USD). That is definitely seems like a big ask, BUT let’s compare it against comparable equipment. A fully loaded SR22 Turbo is just south of $1 million, Piper Seneca is just about $1 million and the Beechcraft Baron is around $1.4. A major factor to consider in pricing is direct (per hour) operating cost. The Diamond sits around $200 per hour - this price includes fuel burn, average maintenance, and engine overhaul reserves. At $200 it is more expensive than the single engine Cirrus but substantially less than the Seneca or Baron. I’ve heard the argument that at $1.2 million the DA-62 competes closer to turboprops like the Meridian or TBM. I could not disagree more strongly. While in the same initial capital territory the operating costs of a Meridian would be more than double and annual costs will be higher.
All in, I’m very impressed by the DA-62. The combination of speed, load capacity, and comfort are compelling. However, I think the argument for the DA-62 is greater than just a handful of features, I believe it raises an age old debate - single vs. multi engine? I could (and probably will) write convincing arguments for either side, but it is a huge step forward for multi-engine market to finally have an airplane worth talking about. Looking for a 7 passenger hauler? The DA-62 should be at the top of your list.