How Diamond Builds Composite Airplanes


Diamond Aircraft builds composite airplanes in two factories, one in Austria and one in London, Ontario. In this long-form video, AVweb’s Paul Bertorelli reports on how the Ontario plant turns out the DA40 single—both the Lycoming and Austro diesel versions—and the impressive DA62 twin.

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  1. I had the opportunity to visit the London, Ontario factory on several occasions about twelve years ago when they were going gang busters building 20’s and 40’s. You can’t imagine how well built these aircraft are until you actually see it. The whole operation top down is very impressive, or, at least it was way back when. The people couldn’t be more friendly and accommodating. I don’t know how it its now, but, ten twelve years ago I had no problem getting a factory tour just about any time I wanted. If anyone is able, I strongly suggest calling up Diamond or e mailing them to try to get a tour of the facility. Even if you do not fly a Diamond, it is definitely worth your while. My bet is, if you have ever been on the fence regarding a Diamond aircraft, you won’t be after the tour.

  2. Good video, Paul. If anyone wonders why composit aircraft have not totally replaced all-metal designs, the tremendous amount of hand labor involved is obvious here. Plus the huge amount of waste material generated in the vacuum bagging process is obvious. The electronic quality checking of the avionics wiring layup is very impressive so that the finished wiring loom should be trouble free.

    While composit construction is labor intensive, the video demonstrates how it enables both the sleek, aerodynamic design, as well as the high strength of the wings and how they safely incorporate the sealed and welded aluminum fuel tanks. Overall, an excellent factory tour. Hope to do one in person some day.

  3. Outstanding job!

    Interestingly, the principles of composite construction seem to have changed little from the ’70s and ’80s when we laid up whitewater kayaks by hand. What is truly breathtaking is the level of automation Diamond has brought to the process.

    As other commenters have stated, a first class operation from start to finish.

    • You want to see something impressive, you should see Diamond’s CNC machine. It is huge and very impressive. I forgot what it all cut out. I think it was the instrument panels, other misc. parts, pieces and that was 12 years ago. I remember it cutting some really thick stuff like 3/8” and 1/2.”

    • Kim, unfortunately you are correct; little has changed in the actual layup of parts. The initial cutting and pre-preg process is more automated, but the final bagging process is pretty much unchanged. One thing that stands out with composit construction is the requirement for strict cleanliness standards. Any airborne dust can quickly contaminate the molds, leading to ruined parts. No amount of preparation for painting will cover over a grainy surface. The impeccable paint we see in their finished aircraft demonstrate their attention to cleanliness in the manufacturing process.

  4. I enjoyed the video showcasing the build of a Diamond aircraft. An average for Diamond is 2500-3500 man-hours to build and deliver an airplane depending on single or twin. Cirrus build times are similar at 2800 man hours averages for their piston single aircraft. It has taken Diamond and Cirrus decades to get to this level of efficiency ( depending on one’s definition of what efficient really is) of hand-built aircraft. Diamond stated 23 man-hours to complete a Garmin panel, less wiring, and air-frame installation. There were lots of work stations dedicated just to build the wiring harnesses from start to tested finish. They did not say how many man-hours that entire process took. I suspect 150-200 man-hours total would be reasonably normal. But they did track percentages of efficiency as it related to each work station throughout the hand-crafted build.

    Looking at what Diamond has to do in body work on a completed air-frame is still, good old-fashion grunt body work that accounts for 100’s of man-hours to putty, block-sand, primer fill , static prime, and then hand-shoot the paint. None of the video showed the layout work required for a three color paint scheme, and the paint shooting sequence to complete the paint job. This is why custom car builds are six figures. An airplane has two to three times the surface area of an average car. That is why an average used single engine airplane costs $15K-35K at a refurbishment shop. Having experience in painting both Cirrus and Diamond Aircraft, $26-40K is the norm because of certified paint process required which in the case of both Diamond and Cirrus are proprietary blends plus the chemical/type data required sequence to strip and re-paint just as is done at the factory when new. If not adhered to in all phases of refurbishment, the airplane does not meet type data specs and therefor is not legally airworthy. Having the local PMI/FSDO/OEM lawyer get involved debating the airworthiness of the refurbed airplane makes for some interesting dialogue.

    This is why the majority of the Cirrus and Diamond certified service centers refuse to strip/repaint, do warranty touch ups, or insurance work. This is why many customers of composite airplanes are stuck in 6-9 months waiting periods for warranty and/or insurance repairs let alone a complete strip and paint. Very few places want to do this. This is another reason why both manufacturers are in the refurbishment business because of the technical/chemical, and man-hour requirements learned in the original manufacturing process that must be adhered to and applied when the air-frames get older requiring refreshing.

    Looking at the activity of employees in the background, at all levels shown in the video demonstrates a hand-built airplane at each work station, hand loaded on the rotisseries and jigs with a block and tackle, carefully hand lowered, picked up or turned. Many were looking at tablets and consulting manuals ( a good thing), with carpets and plastic taped all over the place as one climbs in and out of the airplane to complete the task. No sense of assembly line frenzy, speed, robotic automation because that automation is very limited for airplanes, especially composite airplanes, of which selling 100-400 per type per year is a banner year. Nine layers of composites including the protective peels to build the wing, tail components, and fuselage skins just to get to the vacuum bagging process. All of it hand laid up. Diamond and Cirrus look like a well organized customer assist build center with employees supplying the labor in lieu of the customers actually being there.

    I am very impressed with Diamond’s sense of quality, reliability, and craftsmanship. It is clear they have invested heavily in a trained work-force. They have to because composite airplanes are still hand-built, custom aircraft. I too, am surprised that Diamond can deliver such levels of engineering and quality at $500,000 dollars.

    The world market for $400,000 – 1 million dollar airplanes is about 800-1000 per year total. Those figures have not changed much since the resurrection of piston singles in the early to mid-90’s. When airplanes sold for modern dollar equivalents of $100K or less, sales were 15-17,000 per year in the late 70’s. Van’s alone has demonstrated those price points with 12,000+ sales and climbing. It takes 12-2000 man-hours to complete an average Van’s kit with total expenses less personal labor at $100K or less, many averaging $60-80K complete including paint by folks who never built anything let alone an airplane. Maybe not Oshkosh Lindy quality but solid, airworthy, well equipped, and appealing airplanes. That suggests that to reach any levels of remotely meaningful economy of scale manufacturing 15-20,000 airplanes per year, a completed airplane must have the performance, style, handling, performance capabilities, automation, and price similar to a Van’s product. Anything costing more and delivering less reduces aircraft sales to our current levels.

    It is pure fantasy, as far as I am concerned, that “urban mobility” vehicles, which presently depend heavily on composite construction can gain any economy of scale in manufacturing. Plus, FAA regulations to come will include the present acceptable composite construction the FAA currently has knowledge with. While carbon fiber technology exists that can gain some benefit of automation as demonstrated by Elixir, it is still foreign to the FAA and its understanding of acceptable composite construction throughout the majority of the air-frame. That means more regulation regarding certification testing which is required for any commercial flying machine that can carry more than 50 lbs, human or otherwise. That is not including certification tests of the multiple electric engines, ESC’s, and batteries. It’s one thing to certify a new composite air-frame with an accepted and certified power source such as a Diamond, Cirrus, Windekker, or Epic aircraft has done. And all of those completed certifications were extraordinarily expensive and time consuming. Now add at to that recipe, new power-plant technology.

    Uber, Amazon, FedEx,etc., have a relatively naive conception of the expense, time, stamina, and sheer willpower it takes to get through the FAA regulatory certification process. Maybe they think their money and business power will supersede that of a bloated, tax-fed bureaucratic juggernaut like the FAA. If I were a betting man, my money is with the FAA as the stronger. They have an unblemished record so far. Especially for regulations that are getting written, debated, and reviewed as development of new technologies mature or die.

    The 3D world of aviation has safety challenges unlike any other mode of transportation. For some reason in our homogenized, uni-sex thinking society, flying machines, particularly those who carry humans, can be developed like a car. Airplanes are definitely not a one size fits all machine. But folks continue to seem to think the problems of flight can be solved by some sort of algorithm.