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Ilkay Özkisaoglu

Since 04/2021 229 Episoden

#217 Engineering the DA62: Inside Diamond Aircraft’s Composite Production

20.05.2026 38 min Staffel 5 Episode 175

Zusammenfassung & Show Notes

🔧 Inside Diamond Aircraft: Composite Manufacturing Deep Dive | DA62 | AERO 2026

This 33 minute full length engineering interview takes you inside the composite manufacturing heart of Diamond Aircraft at Wiener Neustadt, Austria — one of the most advanced composite aircraft production sites in General Aviation.

Recorded as part of the AERO Friedrichshafen 2026 preparation, this episode features a deep technical walkthrough with Gerhard Hüttinger, Quality Manager at Diamond Aircraft, guided by Norbert Werle (Founder, JET Circle) and Ilkay Özkisaoglu (DER Social CEO & Co Founder, Composites Lounge).
The focus of this video is not marketing — it is process, structure, safety, certification and engineering logic behind Diamond’s composite aircraft, with special attention to the DA62 as a benchmark for composite driven business and multi mission aviation.

🧩 What You Will Learn in This Interview
✅ How Diamond manufactures 95% of its aircraft structure in house using advanced composite processes
✅ The difference between wet lay up, vacuum assisted infusion, and “just in time prepreg” workflows
✅ Why Diamond deliberately avoids classical autoclave curing — and how post curing up to 125°C achieves final strength
✅ How carbon fiber, glass fiber, Kevlar and foam sandwich structures are combined for optimal stiffness to weight ratios
✅ Why the DA62 airframe is ~98% carbon fiber
✅ Lightning protection strategies: conductive carbon layers, aluminum skeletons, copper foils, conductive paint systems
✅ Structural bonding philosophy — including epoxy bonding pastes capable of filling gaps up to 10 mm
✅ Why Diamond designs for failsafe structures and unlimited lifetime concepts
✅ How landing gear loads, crash energy (26g), and impact absorption are managed through composite optimized seat structures
✅ Precision CNC cutting and manual finishing — where automation ends and craftsmanship begins
✅ Full serial traceability from raw material to delivered aircraft
✅ Why Diamond prefers aluminum fuel tanks over wet wings in composite aircraft
✅ Composite center wing box philosophy and fuel safety between twin spars
✅ Installation logic for radar, avionics, oxygen systems, de icing, and special mission configurations

✈️ Why This Matters
Composite aircraft manufacturing is no longer an experimental discipline — it is a mature, safety critical engineering system shaping the future of General and Business Aviation.
Diamond Aircraft demonstrates how composites: • Reduce weight without compromising crash safety
• Enable modular manufacturing and scalable production
• Support business travel, charter, training, and special mission use cases
• Deliver long lifecycle durability with predictable maintenance
For engineers, OEMs, suppliers, regulators, flight operators, and composite professionals, this interview offers real production insight — not slides, not theory.

🎥 About This Series
This video is part of the Composites Lounge × JET Circle field research series ahead of AERO Friedrichshafen 2026, documenting how materials, engineering and business aviation intersect in real manufacturing environments.
📌 Recorded on site at Diamond Aircraft, Wiener Neustadt
📌 Full factory walk through
📌 Zero scripting, engineering level explanations

🔍 SEO Keywords & Topics
Diamond Aircraft composies, DA62 manufacturing, composite aircraft production, carbon fiber aviation, vacuum infusion composites, General Aviation composites, business aviation engineering, AERO 2026, Diamond DA62 structure, lightning protection aircraft, composite fuselage, aviation quality management, composite bonding aviation, failsafe aircraft design

🌐🔗Visit Our Website:
▶Website 1: https://www.dersocialceo.com
▶Website 2: https://www.compositeslounge.com
▶Website 3: https://www.imbeo.de
▶Website 4: https://www.contentcreatorclub.de

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Transkript

Wonderful. Good afternoon, dear LinkedIn Community Composites Lounge members, as we have indicated to you guys, we are together with Norbert Werle, my business partner, preparing for Aero 2026, and we have an exclusive look inside Diamond Aircraft. And together with me is Gerhart Hüttinger(!) He is the quality manager of Diamond Aircraft and he gives us an insight look into Diamond's composite production. What will be expecting us, Gerhard. Just a very quick preview. So we will see the full scope starting from the first lamination process to the final aircraft. So it takes usually about three months to complete one complete airplane from the first part of the final aircraft. It's flown here, it's tested here. And if you pick the airplane, it's also handed over here. -And we will see a couple of composite parts, I guess. -All composite. All of them. That's wonderful. Community. I will hand over basically this tour to Gerhard Hüttinger (!) and Norbert Werle, my business partner, because I will be the cameraman for this tour just after this break. And welcome to the JET-Circle. Thanks for having us here at Diamond Aircraft, Gerhard. -You're very welcome here in our diamond manufacturing facility. We have separated the composite manufacturing process and the assembly benefit process assisted with a maintenance organization, flight training organization, and other supporting departments. Yeah. But here now we start in the manufacturing building for the composite process. -Okay. And here we see immediately the composite. -I want to point to this, this overview because we have two major processes. One is a wet layup process and the other one is a vacuum assisted infusion process. Okay. -So out of this process we produce let's say 95% of the structure. So it's manual layup. So it's one machine impregnating the dry fabric with the liquid resin and hardener. Then it's a manual layup process which ends up with curing under vacuum. -So it's no pre-preg. It's no pre-preg. We call it just in time pre-preg because we impregnate by machine. And so we have the wet laminate in our hands. Okay. So in this process has usually three stages. So we laminate both shells. Then on the second day, we start with bonding of all stiffeners, ribs and spars, cure it overnight, and on the third day we bond everything together. Completely different is this process where we do a dry layup with some kind of membrane and flow channels, and we keep the vacuum while we let the resin flow through the part. So, but this process it needs a lot of preparation, a lot of additional material. So it's quite a cost-intensely process, but you can produce a composite structure with almost zero porosity. So those we use for special parts, like for the radar nose cone, if you order weather radar on the DA 62, now you get a nose cone in this manufacturing process. And the wing spar caps you will see in the production then. Those are also produced in this process. Okay then the curing is at that time just performed at 50 degrees Celsius. So there is no hot curing in the autoclave. This allows us to demolish the parts, cut the parts. And in the later stage we assemble the parts to an aircraft and then it gets to the warm curing process. Yeah, the post curing process is the process which is leading up to 125 degrees. A process takes over 24 hours in total. And then you have the final strength also regarding heat resistance. So then you are also having no problem to paint the Diamond aircraft in a black paint scheme. -We have to demonstrate different color codes. So the darkest that we have demonstrated this is anthracite. -which is the demonstrator now. Exactly. We have not demonstrated black. -Okay. So you would have some let's say outset temperature restrictions if you insist on a black aircraft. Okay. And here we see out of this vacuum assisted process a sample what is possible to produce. So this big part, including the stiffness inside was produced in one shot. Was the fuselage for the DJet project. Later then the floor and the front is bonded. But this is the one shot out of a vacuum assisted process. -So no half like in that case. Exactly. So here we are now in the manufacturing room. So you will see the impregnation, the layup, the curing process. And in a separate room is then the cutting process. And do you manufacture all airplanes in here, or do we have different production lines for the different types? We have several composite suppliers in the neighbor countries regarding components. The major components for a few types are produced here, and some we get from our facility in China. But the major are here and but you don't have a dedicated DA62 production line or DA20 production line. It's all mixed. -We do all at the same time. But of course there is a 62, 42, a 40 and DA 20 production line. Ah, okay. It's not interchanged in the same place. No. It's mixed, you know, because each aircraft type is usually at the moment produced in a five day process and on Monday we start with DA62, on Tuesday with 42. So. -So in that process then okay. By the times. -So can you see our different types of impregnation machines. So most of them are in-house built in-house designed and in-house built. Those we use at each of our facilities. And they give really a reliable impregnation of the dry fabric. -Okay. The fabrics that we use are mainly glass fiber and carbon fiber, where they let's say the larger the aircraft, the more is the carbon content. -Okay. How much is in it to DA62? The percentage of. -98% of Carbon fiber. So only things like nose cone and so on. Then those kinds of things? okay. Here we use different types of fabrics. So glass fabric with a strength like aluminium, carbon fabric in a strength like steel. And those are specially designed for manual lamination. So this carbon fiber has a strength like a steel. And it's a special design feature we use a carbon fiber with a small wire woven with the fibre to make it lightning protected. So when the lightning occurs, this layer will distribute the energy to reduce the local damage. And so all our carbon aircraft are covered. The last layer with this special fabric already said before, this is the end of the second stage. So all ribs and stiffeners were already glued to one side. The glue with the same epoxy resin which we used for lamination, make it to a paste with a mix of cotton flux and silicium bubbles. Okay. -And with this bonding paste, we can fill gaps from 1 to 10mm without any issues with the same bonding paste. You see some overlapping area between the left and the right shell. And each of these ribs is bonded on both sides. So this gives the strength to the structure. And at the end, a fuselage of a 62 will have in total around 150kg -150kg only? Okay. And then you have those few spars and, few ribs on the floor in there. Right. -Exactly. Okay. -So. And you see, already the place within the huge center wing is connected to the fuselage. Yes. Of course. Okay. Further feature for lightning protection is that we have a complete aluminium tube skillet through the whole structure. And in this skeleton we lead the necessary wiring. So if the lightning really succeeds to get through the structure, it runs down the aluminum skeleton and does not influence the necessary wiring. -Okay. Because we have an ECU controlled engine with a Garmin system flight management system. So we like to have electricity. Yes. And like all the cables are protected by the tube essentially done because the tube takes over the lightning protection energy here. So carbon lamination is a certain challenge in regards to glass fiber elimination. Because in glass fiber you see if there is air between the layers and you can focus on getting the air out. On carbon elimination you really have to do the work. Good workmanship. And you have to see and feel if there is air between the layers. -And to push it really out. That's why most of our composite employees are here ten years, 20 years already. And they feel where is the bubble? -Yeah, exactly. Big surface parts like wings, fuselage. We integrate a foam into the structure to get the sandwich part. Yes. So we get some distance between the outer and inner layers, which are more stiff at the same weight? Yes. Yes. Typical structure for hardening the structure. Exactly. And those are the center wing spars. So with these four bolts, they connect both wings. They take the loads from the landing gear. Yeah. So the landing gear is connected here? -Exactly. And on top will be the fuselage at the end. And those parts are not produced only on the vacuum but in additional in the pressure tube. So we call them autoclave even it's not heated. Yeah. But we have another three bar outside pressure on the vacuum bag. And so we get a high condensed carbon fiber. -Okay. Through the pressure of the vacuum then. -Vacuum plus 3 bar pressure additional pressure on the vacuum bag. Okay. Yeah. And as you can see here, specially designed we have the landing gear mount glued to the spar. So if a customer does an ugly landing, damaging the structure is either cracking those ribs. Or the bonding. This can be replaced and the center wing stays alive. And how can you make sure that there are no cracks than in the central wing? because it's difficult to check the carbon fiber later. -The carbon fiber has a higher strength than the other bonding. -So this will for sure crack the bonding before. -And as we like to do a lot of composite gluing, we have to take considerations how to get the force, for metal parts into the composite structure. And our solution is that we integrate three pre-pressed glass fiber plates into the structure. So the dark green areas here is a pre-pressed glass fiber. -Okay. Those are integrated into the structure. And so we get the load transfer from the composite to the metal part. -Okay. And you would need then only to exchange this part but this one stays intact. Yeah. -Okay. But the wings can be always dismounted through those. Yeah. -You remove the stainless steel bolts. Yeah. And then take the wing off. So here you see the integration of the centerwing spars into the centerwing structure. You see the gluing process live. So we always bond with over amount of bonding paste. Put them into into place with a certain fixture. And then we clean the over amount. So like it looks here will be the final. So this is the fixture that keeps everything exactly at the right place. And then it will be glued. And then after it's hardened you take away the fixture. Yeah exactly. -Okay. And this is then the center wing which is connecting the wings to the fuselage. Exactly. So there will be similar bolts like this connecting the fuselage. This is here the place for the engine mount. And on top here will be the fuselage. And here you see prepared already ready to be glued components of the center wing. So, you see, they are already prepared on and on the fixture. The bonding area is rough, which we achieve with a peelplyfabric and additional hand grinding. So this has to be perfect rough and clean for the bonding process. For the bonding. Okay. So don't touch it now. So this is our big CNC cutting machine. Because you have to produce composite parts with oversize and then cut to the final edge. You cannot produce a perfect edge on composite. So all big parts are cut on this machine. So the wings and the wing fuselage. So it's 5 axis machine. Taking the optimum tool for the cutting process and all other smaller parts are cut by hand. -Okay. But this is pretty much automized. This is a CNC automized machine. -Okay. So he is only controlling what is happening there. -Yep. Wow. That's a lot of production know how that is in there. But as I know, aviation is extremely much also paperwork and certifying everything that every part is tracked and everything is to the maximum safety. How is that handled within Diamond? Yeah. So we have a full traceability back to the raw material. Back to the operators, back to the inspections. We still work with paper because it's for us still the most comfortable solution. One day maybe it's electronical. But in this documentation we have the full traceability of each component installed on a composite part. Which raw material was used for the working steps and the inspection steps are confirmed. This is the way how we track the production and inspection process. -And that's always for one part of the serial number of the appropriate airplane. Correct. And the end you get the big aircraft log with all documentation. So that will be handed over to the owner. -A selection of those. Okay. But you have it on file for everything. Exactly. -All times. Because we have to keep it for the lifetime of the airplane. In the pre assembly process, we take care that all parts fit together. So we do a pre assembly of the complete aircraft. Okay. -Yeah. Because each bonding everything that you do on the aircraft needs to be heat treated. Yes. -So. And then when everything sits on its place we go to the heat treatment process. What I said before 125 degrees heating up. And then we get the final structural strength and heat resistance. If you want to know where you put the luggage. Then you see it here. There is the luggage compartment in the nose cone of the Diamond DA62 is quite small area, but in the back is also some larger area later. So for the three layers of painting we start with an electric conductive paint. -Aha! Then comes the color code and at the end the top coat. The clear coat. -Why? Electric? Electric. Conductive paint? -When you fly through electric loaded air, you collect in this layer the electricity and you put it to the discharges. Okay. To do the static discharges, those little things that are at the back of the wingay. Yeah, exactly. Okay. So here I can show you, um, one of our safety features. Okay. -Yeah. Those are these so-called crash elements. So our seats are not movable. Our seats always sit on the front edge on a strong spar. And on the rear seat they are quite flexibly mounted. Because if you certify nowadays an aircraft, you have to demonstrate that you could survive a standard aviation crash which is 60 degrees against Earth. Initial impact 26g. Oh, okay. Just to demonstrate that your structure can absorb 26g. And this we achieve with an almost indestructible seat which is made of carbon and Kevlar fabric and some shock absorbers. So those elements will absorb the load in case of a crash. So these are for the rear seats. That will be for the front seats. The same shock absorbers. But that means that such a shock absorber needs to absorb something like 2.3 tonnes, 2,300kgs or something. Because if I'm no, not almost 100kg. No, not that much. But no, you absorb with the whole structure (the seats and the surrounding structure). -With the whole structure. But but here essentially impact with 26g gives you also 2.3 tons here on to those holding devices in that moment. Right. -The 26g is for the whole structure. Okay. -Yeah. So demonstrate that with the whole let's say element. That's the whole fuselage. The Dummy is sitting on the seat get a survivable load. So it's acceptable that the rest of the structure absorb already a part of this 26g. So you don't have 26g on the seat. On the person. -So this is the center wing to the blue fuselage to Saudia (?) okay. It's already prepared with those crash elements. It's always prepared with the copper foil. Copper? Is that copper? -The copper foil is a protection against high radio frequency. Because there should be no impact on the aircraft if you fly over radio station. Yes. Okay. And that's often at the airport, of course, that you have such radio stations. -But could be really radio. So music radio stations as well. -Oh, okay. Good. Yeah. And as long as we don't have a metal structure, we have to add on certain places some metal. Okay. Also additional protection for the passengers inside. And pilots. Mainly for instruments. -Ah. It's not I mean, the humans would survive. But you have to protect the electronic devices. Okay. As I said before, these are our non-destructive seats and -Seat bottom. Now, here. Exactly. We look from the bottom. So here you see our carbon Kevlar reinforced seat. -The yellow is the Kevlar in there. Kevlar is exactly. This is the edge where it's sitting on the spar. And here will be the flexible mount in the rear. And all of this structure we covered then with nice leather. That looks good already. And here is the control stick then. Exactly. -Good. Now here. That looks strange. That looks not that more like a wing. Okay, let's focus first on the on the wing. Fuel wing, fuel tanks. So it goes into the wing. -These are aluminium tanks which are flexibly connected that they can follow the movement of the wings. -Yes. Okay. If because of bending of the wing. -And we prefer the solution of aluminium tanks for several reasons. One, it's easy to install and maintain. So if there is any issue, you defuel it. You take it out, you fix the issue, install it again. -Okay. So for us it's very much easier than a wet wing. You know, for instance. And aluminium is still a lightweight material. -And wet wing would mean that there is not a separate tank inside, that the structure is. Covered by a sealant. -Sealant, and the structure is already giving the tank. But in the big airliners, it's always wet wings. Right? -Yeah, but the it's easier that you get somebody with a mask walking in and fix the issue. Yeah. You don't walk in there. -On our airplanes. It would mean cutting a hole to fix an issue. Okay. Yes. -Our auxiliary fuel tanks. From the 62. So they are sitting behind the engine mounts. Okay. -Give you another 50 litres of fuel? Yes. -And those are produced in rotation. Melting process. So you have two half mode. You fill in a defined amount of powder. You start rotating and heating. So that everywhere in. -It starts melting and everything is covered with the same thickness. Because of the movement. -Then it is rotating in a certain movement to get the constant thickness. And by this you can integrate fuel lines and other elements into the tank. -Nice. So that means you have a mold which is done. Exactly. Having all those forms in there. Yeah. Interesting. -And it's the same process like sports kayak are produced. -Okay. So now we have here the part of the wing and tanks already installed. Right. Correct. Yeah. So it's quite easy. There are a few elements holding the tank inside. There are a lot of fuel rips keeping it in place, but just two screws, and you take the tank out and put it in. -You can take it out from here. Exactly. -Okay. Here. You see already the copper bushings. But then the main bolts you call the main bolts. Connect the center wing with the wing. Okay. And the same then for the small connectors here for all the control surfaces. -Exactly. We operate our controls with pushrods there. So only the rudder is operated with cable needs. -Now you can push it and then you can see. Can I see the push? -You can see the push. And out there the aileron is this. -Is the aileron moving. This is the, the here for the landing flap. We just block it here for transport purposes. So this is the connection to the landing flap. Perfect. -As all of our airplanes can also be used for training purposes. You can all of our airplanes steer from the right or the left? -Yes. Both sides. Two wing spars. As you have seen already on the center wing spar. We have two of them for several reasons. One is an unlimited lifetime. Unlimited lifetime? -unimited lifetimes. Usually you have every few thousand flight hours a structural inspection, and you extend by the next 3,000 hours. Second is, we have demonstrated, failsafe design. So if one spa would fail, the other one can still guarantee a safe landing. Okay. -And the third best reason is that we have a very protected place for the fuel. So it's really protected by two spars. So in case of a crash, it's very unlikely that our aircraft burns. So essentially that also means that in this case, the lifetime of the airplane or the age of the airplane doesn't matter, because it's for sure, from the structural point of view, always a safe airplane. -We have to demonstrate this, this fatigue demonstration for the major components. That's why we came to this inspection steps and the unlimited lifetime. -So you demonstrated that it's so durable that it's unlimited lifetime. You can be guaranteed there on it. If I remember right, I think there were more than 10,000 load cases. And here is already the engine now connected and installed. So there were some preparing assembly steps before. So the major marriage that we call is when we connect the fuselage with the center wing. Yes. Because from that moment on, they stay together for the rest of their life. And when this is done, we can start with the engine installation. In this case, it's our Austro Engine, diesel, alias jet engine. And you can see already. Also some options that are available to the customer, like an oxygen bottle. -Yes that's important. So you connect your cannula and you take the oxygen that you need. Because the engines are certified up to 5500m. Okay. -But the human will need some oxygen in between. That's how it will be this case. Then what we see in the later assembly for the weather radar. And you can also choose the option for the de-icing. What you see better than on the installed wings. Yeah. All important safety feature that the eye is seeing the oxygen, especially in commercial aviation and in passenger flights that we do. Just out of curiosity, why is the blue here? So we have a different color for cooling hoses, different color for fuel hoses, so that it's clear to everybody which medium is flowing through there. -Perfect. So here is already almost finished or -Correct. So we had some assembly steps. We have a detailed inspection before we assemble the airplane and then assemble the airplane. Then we start with all system tests of hydraulic, landing gear system, avionics system, de-icing system, all features. In this case it will be a multi-purpose platform. -Yes. So that's why there is the option of on top exhaust available. Why do I have no infrared signature for those on the ground who don't like that you survey them. -Are to be in disguise. Exactly. And here you see our de-icing panels. These are titanium panels. Which are very fine laser drilled. So there are holes in. -The holes inside? Exactly. You need good eyes to see the structure of the holes. So we have a fluid, the de-icing fluid tank on board, Which we switch on the pumps and they start to cover the wing. The cover, also the aileron, the landing flap. So it's an ice avoiding system. And this allows you to fly a certain time depending on the mode that you switch on in icy conditions. So you can safely fly over the Alps in icy conditions, and it's. Certified for flight into non icing. -But the strange thing is here in the front. -So this is the very popular Garmin weather radar. -Aha. So it it delivers you the real weather in front of you. You can tilt it left right up down. -Yeah. Like a radar dish here. Exactly. -So this is the radar dish. This is the radar. -Exactly. And it gives you on the Garmin G-1000 the real weather information in regard to your flight route. So you can really then divert five degrees, ten degrees to the left, for instance, to avoid ugly weather in front of you. -Okay. And is it only this small item, or is there a big instrument also connected with it? This is for the radar. It's this component. And the rest of the garmin system will be installed here. So this flight data, computers, air data, computers and everything will be installed in the big garmin box. -Okay. So you have one more box in here if you have the radar additionally. No. This is the standard box. And the option weather radar just adds the device in front. -Ah, okay. Yeah. Because you get all the avionics equipment already here and have just let's say the screens installed inside. Here is already the cockpit line. -Exactly. Looks like. -And as we said already, all the avionic units are already in the Garmin box there. That's why on the cockpit we can focus on the screens, on the buttons and switches and on the fuselage fuselage. So here is only the human interface to the pilot. Exactly. -But still lots of cabling and lots of different connectors. How much cable is in such an airplane in the end? -It's hard to estimate. I would say several hundred meters. -There are kilometers, I thought as well. Yeah. So we have here the DA 40 already almost finished. Right? Correct. We have the last inspection and the last tests on the assembled airplane. Before we go out for the first ground run. So we monitor with the laptops if the ECUs are happy in this case, ECU for the single engine. And then we do all tests on the running engine. And if everything is satisfying, we release the airplane for the production test flights, which takes us usually about three hours, including a landing in Graz (Austria), where we have to demonstrate that the autopilot can fly. The approach, it cannot land, but it has to be able to fly the approach. And then after those three hours, we have the last finishing department where we prepare for the handover to the customer. So it gets the registration and the design finally, and then any kind of handover to the customer either here. Some of them get also their differences training here on their new airplane. Or we bring the airplane to the dealer and the dealer hands over the airplane to the customer. -Can you do the ferry flight? And then it's taking over locally. -For long ferry flights we can install a ferry tank instead of the rear seats, so we can fly legs up to 12 hours. -Okay. With the ferry tank. -And then you install the rear seats locally on the final. -On the final destination, we replace the ferry tank with the original seats. Okay. Interesting.