Richard wrote:However I'm still not convinced about the benefits of your approach to modelling - so what I'm now wondering is if it's time for me to build a model to compare against one of yours - and see what comes out of this. I don't know if you're interested in doing this as - but if you are then pick what you think is your best model, give me the geometry and airfoils, propeller RPM and CT/CP and I'll put it through my aero builder and we can see what comes out.
I've handed over the data I used for this plane to Richard, and he's going to work on a flight model using his aero builder..
As this is the first time anyone has actually challenged me with regards the authenticity of my FDM building approach I'm really excited by this. The results are important but for me more important is the reviewing of one flight model against another. This is a step forward, and hopefully we'll see more like this.
Richard isn't convinced of the benefits of my approach to modelling. Yet it might be that this experiment doesn't yield an answer other than 'which is the better feeling flight model'... not that this isn't a good answer within a flight sim, however other benefits might and should also exist such as.
1) I'm interested in WWII bomber combat sims and simulating the flight characteristics of a damaged plane has driven the whole approach.
2) in reality very few planes have comprehensive wind tunnel testing data, so we find an every greater number of planes relying on guesswork figures for the co-efficient tables. And this guess work has no relationship to any of the values used on other plane of it's era, which in reality isn't so, as this relationship is very important. Improvements in flight were all based on what the last best planes performance was and how we could beat it with our new plane. So we see plane designers building on the development of previous planes, using lighter stronger materials, new airfoil designs, greater engine ratings etc..So in my mind flight modelling should reflect this.
3) Lastly I believe that the characteristics of a plane should be left to physics and should not use tables that fudge an effect such as spin etc. Easily understood forces should be applied here for lift, there for side and at this point for drag, all with an understandable level of error that is acceptable and the effects should fall out, either it flys or it doesn't. No plane 'hits every number'... because when you see a top speed for a prop plane, this is with it's speed prop on, it's best climb rate is with it's climb prop on, and it's cruise rate is with it's cruise prop on, it's horses for courses when it comes to a prop plane.. the Schneider trophy wasn't won by designers using a cruise prop believe me.
The question I want to ask those that do other disciplines on a plane is do you guys want to work on these parts of the plane at the same time... a collaborative effort ?
Simon
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