Diamond DA62: The Most Economical Twin You Can Buy

Twin-engine piston aircraft have a reputation for burning money — two engines, two propellers, double the maintenance, and a fuel bill that scares off most private buyers. The Diamond DA62 was built to break that pattern, and it largely succeeds. For operators who want the redundancy of a twin without the running cost that usually comes with it, few aircraft make a more rational case.

The diesel advantage

The DA62's defining feature is its pair of Austro AE330 turbo-diesel engines, which run on Jet-A1 rather than avgas. That single design choice cascades into real savings. Jet-A1 is typically cheaper than 100LL avgas and — crucially for operators outside North America and Western Europe — far more widely available, since every turbine aircraft uses it. The engines are also remarkably frugal: combined fuel burn is closer to that of a thirsty single than a traditional twin. The result is an all-in operating cost in the region of US$220 per hour for a four-to-seven seat twin, which genuinely undercuts many high-performance piston singles.

Single-lever simplicity

Older piston twins demanded constant attention to mixture, propeller and power settings on two engines at once — a real workload, especially single-pilot. The DA62's FADEC-controlled engines reduce that to single-lever power management, and the Garmin G1000 NXi flight deck ties it together with modern automation and situational awareness. The effect is a twin that is far less demanding to operate than its predecessors, lowering both training burden and the chance of a mishandling error.

Redundancy where it counts

The core reason to choose a twin is what happens when an engine quits. The DA62 is designed for benign engine-out handling, so the loss of one engine is a manageable event rather than an emergency that bites unprepared pilots. For operations over water, mountains or sparsely populated terrain — or simply for operators whose insurer or risk policy requires two engines — that second engine is the whole point, and the DA62 delivers it at a cost that does not punish you for the privilege.

Who it is for

Where a diesel twin fits

The case for a modern compression-ignition piston twin rests on a specific combination: the redundancy of two engines, the fuel flexibility of running on jet fuel rather than avgas, and operating costs closer to a high-performance single than to a turbine. For operators in regions where avgas is expensive, intermittently available or being phased down — much of Asia, Africa and parts of Europe — that fuel argument alone can be decisive, because jet fuel is available essentially anywhere that turbine aircraft operate.

The economics rest on fuel burn and fuel price

Two effects compound. Compression-ignition engines are generally more fuel-efficient than comparable spark-ignition engines at cruise, and the fuel itself is usually cheaper and more widely available than avgas. On a long sector the difference in fuel cost is significant, and it is the main reason these aircraft appear in flight-training fleets and utility roles where hours accumulate quickly. The savings scale with utilisation, so the case strengthens the more you fly.

What offsets the savings

Against that, these engines carry their own maintenance profile, including scheduled replacement or overhaul of certain components at defined intervals, and gearbox and accessory items that spark-ignition engines do not have. Acquisition cost is higher than a comparable single. Any honest comparison must model the engine and component reserves hourly rather than looking at fuel alone — a common error that makes the economics look better than they are.

Redundancy has a cost and a value

The second engine is the point, but it is not free: two engines mean roughly twice the engine maintenance exposure, and multi-engine flying carries its own training, currency and insurance requirements. The value side is equally real — for night operations, flight over water or inhospitable terrain, and for clients or insurers who require two engines, redundancy is not a preference but an entry condition. As with turboprops, resolve whether twin capability is required before comparing costs.

Training and utility roles

Flight schools are natural operators of this category because their economics are dominated by fuel and utilisation, they need multi-engine capability for training, and jet fuel simplifies their supply. Similar logic applies to survey, patrol and light utility work where endurance matters and the mission does not justify a turbine.

The honest comparison set

The realistic alternatives are a high-performance single, which is cheaper to buy and run but has one engine; an older conventional piston twin, cheaper to acquire but usually thirstier, avgas-dependent and older in systems; or a single-engine turboprop, far more capable and faster but a substantial step up in acquisition and operating cost. The diesel twin occupies a genuine niche between them, and it is the right answer when redundancy is required, jet fuel is the practical choice, and turbine economics are out of reach.

Run it against your own numbers

Because so much depends on local fuel pricing, annual hours and how you account for component reserves, the comparison is worth building for your own operation rather than borrowing. Model fuel, engine and component reserves, insurance and fixed costs across a realistic annual utilisation — our operating cost calculator is a reasonable starting point.

The DA62 suits the owner or small operator who needs twin-engine redundancy, modern avionics and low running costs, flying in a region where Jet-A1 availability and price beat avgas. It is an excellent platform for private travel, light utility and even some training and survey roles. Buyers who need a pressurised cabin, longer range or higher speed will look elsewhere — but for economical, redundant, modern piston-twin transport, the DA62 is close to a category of one.