Diamond DA40 Diamond Star

Updated: October 2026 – A slim, white low-wing aircraft taxis to the runway, the horizontal stabilizer perches at the very top of the fin, a large acrylic canopy gleams over the front seats: you’re very likely looking at a Diamond DA40 Diamond Star. The four-seater from Austria is one of the standard aircraft at many European flight schools – and one of the few light aircraft you’ll meet in a diesel version with jet fuel in the tank. Here you’ll learn how to identify the DA40 with confidence, which versions exist and where you can best get it in front of your lens.

What is the Diamond DA40?

The DA40 is a four-seat, single-engine light aircraft of low-wing design. Its airframe is predominantly composite, meaning fiber-reinforced plastic rather than riveted aluminum. That makes it the counter-design to the classic American training aircraft built in metal since the 1950s and 1960s. The DA40 is used for training private and professional pilots, for touring flights, and by some air forces as a primary trainer.

Behind the type is Diamond Aircraft of Wiener Neustadt in Lower Austria. The DA40 is the four-seat development of the two-seat DA20 Katana, from which it takes the basic concept: low wing, T-tail, large canopy, plastic airframe. The first prototype, designated DA40-V1, flew on November 5, 1997, still with a Rotax 914 engine at the time. The second prototype received a Continental engine, and the third, from 1998, finally the Lycoming IO-360, which went into series production. In 2000, certification followed under the European design requirements JAR-23. At EASA, the type certificate is now listed under number A.022.

By December 2020, Diamond had delivered around 2,200 DA40s, including about 500 of the DA40 NG diesel version. The DA40 was built in Wiener Neustadt and in London, Ontario, Canada; in addition, a joint venture in China’s Shandong province built the DA40 TDI diesel version.

The three features that are enough to identify it

At an airfield with training operations, a dozen white light aircraft often stand side by side. You pick out the DA40 with three looks – two of them work even when the aircraft passes far out on the downwind leg.

If all three points fit and only one propeller spins in the nose, it’s pretty clear. The registration on the side of the fuselage provides the final certainty. Because the DA40 weighs well under two tonnes and has only one engine, a German registration begins with D-E. What the letters mean exactly is explained in the guide to German registrations and weight classes; for Austrian aircraft, the article on OE- registrations helps.

Gasoline or diesel: the versions at a glance

The DA40 comes in two fundamentally different engine worlds. One line flies with the classic Lycoming four-cylinder flat engine and takes leaded aviation gasoline Avgas 100LL. The other line flies with turbodiesel engines and takes jet fuel. For spotters, that’s interesting because diesel light aircraft are still more the exception.

Version	Engine	Special feature
DA40 / DA40-180	Lycoming IO-360-M1A, 180 hp	First production version with variable-pitch propeller
DA40 D (TDI)	Thielert Centurion 1.7 or 2.0, diesel	First diesel version, first flight on November 28, 2002; sold mainly in Europe
DA40 FP	Lycoming O-360-A4M, 180 hp	Simplified version with fixed-pitch propeller, no longer on offer
DA40 XL	Lycoming IO-360	From late 2006, about four knots faster thanks to an optimized exhaust system
DA40 XLS / CS	Lycoming IO-360	From the second half of 2007; the XLS as a well-equipped top version, the CS as a more simply equipped variant
DA40 NG	Austro Engine AE300, diesel	EASA certification in April 2010, running on Jet A-1
DA40 XLT	Lycoming IO-360	From April 2013 with a revised interior
DA40 Tundra Star	Austro Engine AE300, diesel	Reinforced landing gear and larger tires for unpaved runways

The diesel story

Diamond bet on diesel early: in 2002, the manufacturer moved Lycoming production to Canada, and the plant in Austria concentrated on the diesel versions. The DA40 D flew with turbodiesel engines from the German company Thielert, which burn diesel and jet fuel and are operated through an electronic engine control with a single lever. The DA40 D was never certified in the USA.

After Thielert’s insolvency, Diamond was left without an engine supplier. The answer was its own engine company: Austro Engine, founded in 2007 in Wiener Neustadt by Diamond and partners. Its four-cylinder diesel AE300 received EASA and FAA certification in 2009, and the DA40 NG followed in April 2010. A more powerful offshoot of the engine powers the twin-engine DA62. The DA40 D is no longer offered new; used examples keep flying, though.

Telling gasoline from diesel from the outside

From the outside, that’s hard to say with confidence without experience. One hint is the shape of the engine cowling and its air intakes, which differs between Lycoming and diesel versions – the best approach is to compare two parked aircraft directly side by side. Many DA40s turn a three-blade variable-pitch propeller, but some versions like the CS also flew with a two-blade propeller, and the simple FP version had a fixed-pitch propeller. If you’re unsure, the registration in the register tells you which version is in front of you – the engine is usually noted there as well.

Military and special versions

• T-52A: the US Air Force Academy used twenty DA40 CS aircraft as primary trainers from 2009 and replaced them in 2012 with a type based on the Cirrus SR20.
• Austrian Armed Forces (Bundesheer): Austria’s armed forces have used four DA40 NGs in pilot training since 2018.
• Other users: among others, the air forces of Ecuador and Bolivia and the army of Bangladesh use the DA40 in training; Jamaica has also ordered aircraft.
• eDA40: an all-electric training version, presented in October 2021 and in the air for the first time on July 20, 2023.

DA40, DA20, Cirrus or Piper?

With small propeller aircraft, mix-ups are far more common than with airliners – the aircraft are small, often far away and wear similar white-and-colorful liveries. The finder helps you narrow it down systematically.

The most obvious mix-up is with its own family. The DA20 Katana looks like a shrunken DA40 but has only two seats. The DA42 Twin Star shares its design language with the DA40 but carries two engines on the wings. Outside the Diamond family, the Cirrus SR20 is the most important candidate: also plastic, also a low-wing aircraft, but with a tail in the classic arrangement. The Piper PA-28 is made of metal, and the Cessna 172 is a high-wing aircraft – you quickly separate both from the DA40. If you want to practice identifying types more reliably in general, the guides Recognizing aircraft types for beginners and Recognizing light aircraft help.

Why flight schools like the DA40

The DA40 has caught on above all in training. One reason is its safety record: an analysis by the trade magazine Aviation Consumer from 2011 put the DA40 at a rate of 0.35 fatal accidents per 100,000 flight hours – at the time the lowest value in US general aviation. For comparison, the analysis cited 0.45 for the Cessna 172 and 1.6 for the Cirrus models SR20 and SR22 combined. The elongated wings, the low wing loading and the good-natured flying characteristics, especially in stalls, are considered the reasons.

Add to that the modern cockpit. Many DA40s fly with the Garmin G1000, and depending on equipment they are approved for VFR, night flying and instrument flying. Anyone learning in a DA40 therefore sits in front of screens instead of round gauges, as is also common later in the airliner. What lies behind visual and instrument flight is explained in the article VFR vs. IFR.

A few details are unfamiliar to students: the nose wheel swivels freely, and on the ground the aircraft is steered through the brakes of the main wheels. And you don’t board through a side door as on many metal low-wing aircraft, but over the wing leading edge under the raised canopy. If you’re toying with the idea of moving into the cockpit yourself, you’ll find the right information in Private pilot license PPL(A) and Becoming a pilot: the paths to the cockpit.

Where to find the DA40

The DA40 is an aircraft of flight schools and small fields. At regional airfields with training operations, several aircraft in a uniform livery often stand side by side, and in good flying weather the traffic pattern is flown there every few minutes. In Austria the density around Wiener Neustadt is naturally high, but in Germany and Switzerland, too, the DA40 is part of everyday life at many training fields. If you’re traveling to Wiener Neustadt anyway, you can combine the visit with the Aviaticum aviation museum in Wiener Neustadt.

At large hubs, light aircraft traffic hardly plays a role. At Vienna Airport, for example, airliners dominate, and you’ll see a DA40 there only by exception. Whether a DA40 shows up regularly at a smaller commercial airport with its own general aviation area depends on the field in question.

Location	Hit chance	Why
Airfields with a flight school	high	The DA40 is a widespread training aircraft, including for professional pilots
Wiener Neustadt area	high	The manufacturer’s home with plant and test operations
Club airfields	medium	Individual clubs and owners fly the DA40 as a touring aircraft
Trade shows and flying days	medium	Diamond regularly shows its aircraft at trade shows
Large hubs	low	Hardly any light aircraft traffic, capacity belongs to the airliners

A good opportunity to see the DA40 and its siblings together is AERO Friedrichshafen, Europe’s most important general aviation trade show. At airfield festivals in Germany, too, training aircraft often stand within touching distance on the apron. You’ll find more ideas for light aircraft tours in the article Spotting general aviation.

Photo tips specifically for the DA40

Light aircraft are a photographic discipline of their own, and the DA40 has a few quirks you can use.

White plastic airframes are quickly overexposed in harsh midday light. Flat light in the morning or afternoon brings structure to the smooth surfaces; when that works at your airfield, you can calculate in advance with the guide Planning the sun position for your photo spot. Before you stand at the fence, a look at Is plane spotting allowed? is worthwhile – even at small fields, the apron and runway are off limits.

The DA40 compared with other training aircraft

Compared with the classics, the DA40 stands for the modern generation. The Cessna 172 and the Piper PA-28 date from the 1950s and 1960s, are built of metal and are represented at almost every airfield. The French Robin DR400 relies on wooden construction and is recognizable by its cranked wingtips. The two-seat Grob G 115 is, like the DA40, a plastic aircraft from Europe, but a pure two-seater. And anyone who steps up a level after the DA40 often meets the twin-engine DA42 in training – an obvious step because cockpit and handling are related.

Common mix-ups and how to rule them out

Conclusion

The Diamond DA40 is the training aircraft that doesn’t look like a classic training aircraft. T-tail, slim wings, large canopy and smooth plastic fuselage give you the type, the registration the confirmation and the hint about gasoline or diesel. For collectors, it gets interesting when you start telling versions apart: early DA40-180s, the Thielert diesels, the DA40 NG or a rare Tundra Star.