High school teacher spends six years developing the Lama
Philip Diehl from Germany had no interest in programming – until he happened to get involved in machine development for flight simulators, that is. He spent the last six years programming and perfecting the Lama, despite never having sat in one before.
Philip Diehl is 39 years old. He was born in Germany’s East Frisian region on the North Sea and now lives in Stuttgart, and is a high school teacher whose subjects are math and music. All of which actually has very little to do with Air Zermatt.
Despite all this, Philip knows all there is to know about the Lama SA-315 B, a helicopter that used to fly for Air Zermatt. Indeed, he built one himself – down to the last detail, for the flight simulator X-Plane. But how does a teacher end up devoting thousands of hours of programming to recreate an old helicopter? Philip told us all about it.
Philip designed the llama for the flight simulator X-Plane.
Philip, how did you get into this unusual hobby – and why an Air Zermatt helicopter?
I was fascinated by the Lama as a child. I spent four weeks every summer on a hiking holiday with my family in the small Binntal valley and saw lots of transport flights. I also witnessed an Air Zermatt rescue operation at the Mässersee lake, at the time with an Alouette III. A man had fallen and broken his back, and was rescued by helicopter from a complicated rock field at the lake.
During the time I spent in Binntal over the years I was able to admire the Air Zermatt helicopters with their impressive flights in confined spaces. Air Zermatt has also rightly become a renowned helicopter company worldwide thanks to its outstanding performance in rescue operations. All of this really made me want to recreate at least one Air Zermatt Lama machine.
The hobby itself came about by chance – initially I was only involved in helping to prepare the helicopter’s soundtrack, but at some point I started with the programming. I had no experience whatsoever, and got my first programming tips from my brother and the Internet.
How long did it take to build the virtual Lama?
It took about six years before the initial release of the simulator X-Plane 11 (i.e. from 2015 to summer 2021) and then another year (until summer 2022) to add more features and make it compatible with the successor simulator X-Plane 12. I spent the first five years working alone, and it wasn’t until 2020 that I got support from the professional 3D design company Khamsin Studio.
Khamsin Studio was responsible for producing the 3D model and most of the texturizing. I designed the helicopter systems, the sound simulation and the flight physics. I also used physical calculations via plug-ins to integrate missing details in the simulator, including the rev limiter and safety circuits.
And I added some paintwork to represent the helicopter in its familiar red and white Air Zermatt color scheme.
Can you briefly explain how the design works, and how it is programmed?
The design of a helicopter or plane for the X-Plane simulation series is based on the following four key stages:
You start by developing a flight model within the simulator, which means entering the basic appearance of the helicopter and all dimensions and performance data according to reality. This includes the rotor blade profile, the torsion of the blades, the weight of the blades, rotation speeds, engine power, fuel consumption, blade control, air resistance, etc.
The flight model is then refined during countless flight hours with the help of real pilots with real flight experience with the Lama. This is done until it not only flies exactly according to the published manual data, but also feels the same way as the pilot felt in the real Lama. This process worked out well thanks to the help of the Air Zermatt pilots.
The next step is the complex process of designing the sound, with huge numbers of small recordings being linked to the physical values of the simulator or the plug-ins via a sound interface. This works like an unlimited supply of a huge range of mixing consoles and effects units that can be used to blend and adjust the recordings, but also to align them extremely closely to the physical calculations. The result is that our Lama in X-Plane really does sound different from all sides. And when you open the doors, you even hear the turbine noise from outside in the cabin. We managed to reproduce the sound of the Lama in such detail that even the characteristic “rattle and hum” can be heard. The sounds in the simulator are actually based on 75 individual audio recordings, all of which come together to create a highly authentic sound image.
The final step is to develop a 3D model that is as realistic as it can be, generally using “Blender” software for design and texturizing. Movements and animations in this 3D model then also have to be linked to the physical calculations, in a similar approach to the sound development process. This means that the visible 3D model of the Lama also moves as realistically as possible for the user. So we also have rotor blades vibrating in the wind, doors opening and all the displays and controls in the cockpit behaving as they should. Even the air turbulence that makes the airspeed indicator jump and tremble in a hovering helicopter was reproduced in this way.
How much did you invest in this project?
The Lama was released for X-Plane 11 in August 2021 and for X-Plane 12 in September 2022. I didn’t keep any records in the first few years, and unfortunately I don’t know how many hours I actually invested. But what I can say is that I often spent several evenings a week working on the project.
The development is distributed via an online platform and sold directly to end customers in this way. More than 2,000 Lamas have already been sold to aviation enthusiasts and flown by amateur and professional pilots.
Philip is currently working on a small historic training aircraft, a North American T-6. As long as he continues to enjoy the work and it can be balanced with his family life and his actual job, he’s happy to keep on programming these machines. Given the amount of work involved and the limited size of the market niche, however, his passion of digital realization will more likely remain a part-time undertaking than become a full-time occupation.
