# Flight simulation

This topic is 4630 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

## Recommended Posts

I'm sure there have been plenty of topics on flight simulation in the past, but I'd like to start a new one so I can talk directly to fellow game devers. I am obviously interested in writing a flight simulator. As far as C++, game development, and OpenGL 3D graphics go, I am confident I have the skills to handle this... What I would like to do is learn the physics of flight. I've done rigid body dynamics in the past (no constraints or contact forces -- a little over my head), but I had Newtonian physics with gravity and collisions working. In order to stick with the rigid body physics design, I need to some how compute forces for lift, drag, thrust, and gravity based on the state of the airplane. Calculating these forces is the tricky part. I need to learn about flight simulation. I could not find much on the internet. I do have the book Physics for Game Developers, though, and Chapter 7 is a gem devoted entirely to flight simulation. However, the flight model in their demo was far from semi-realistic. The controls were bad and my computer ran the DirectX 3 simulation way too fast. I suppose if I retooled the controls and the 3D, I could have something baseline going, and then it's a matter of perfecting the flight model and writing avionics code. Is there any other literature on this that would be applicable for my project? I know _basic_ self-taught Calculus because I'm only in Trigonometry right now, so the mathematics needs to be somewhat managable. I'm not at the point where I can follow complex differential equations, or even the Linear Complementarity Problems (LCPs) used for computing 3D rigid body contact forces. Also, classical flight mechanics books would not really apply to a 3D simulation... A whole book devoted entirely to flight simulation written in a similar manner as Physics For Game Developers would be perfect. I read about the need to gather necessary data for the lift and drag coefficients from wind tunnel test results in order to model a specific aircraft. Once I have that data, it's just a matter of adding forces based on the position of the ailerons, flaps, elevators, rudder etc. As far as realism goes, I don't know if I'm on the right track with this model. In basic terms, how do professional simulations such as FS2004, Flight Gear, and X-Plane handle their flight models? Are there any suggestions for undertaking this project? Has anyone tried something similar, and if so, what kind of results did they get? Any suggested books, web sites, tutorials, or articles to begin research from?

##### Share on other sites
There is a great book on physics called 'Physics modeling for game programmers'.
A quick search on amazon should find this book.

It starts off with simple physics (point masses), collisions (detection and response), projectiles, spring systems, cloth, buoyancy, friction.
It then shows you how to apply this to cars, hovercraft, boats, airplanes and spacecraft.

I find it is an excellent way to start learning about physics.

##### Share on other sites
X-Plane uses something called blade element theory. The flight forces are computed in realtime based upon the aircraft's geometry.

MSFS uses large tables of data on how the plane responds under various conditions. This is great when you already know how the plane responds.

Flight Gear has at least 3 swappable flight engines that use varying systems.

Might help if you brushed up on fluid dynamic simulations.

1. 1
2. 2
3. 3
Rutin
20
4. 4
5. 5
khawk
14

• 9
• 11
• 11
• 23
• 12
• ### Forum Statistics

• Total Topics
633656
• Total Posts
3013186
×