no news on other WW2 addons?

I wonder if the lack of WWII planes being offered by 3rd party is due to the fact that ED basically told them to keep dreaming, we're developing them.

Incorrect. Third parties are being encouraged to develop 2ndWW aircraft.

Incorrect. Third parties are being encouraged to develop 2ndWW aircraft.

The big issue is collecting the proper data to build a plane comparable to the P-51. Data that was collected 50-60 years ago, some of which, depending on what country, was scattered about or archived is some deep dark place. Someone stated somewhere that most Russian planes of that era have limited to no data available for them... so its a challenge. Most of the stuff available online is ok, but the wind tunnel data, etc is the tough stuff to find.

If you want to make IL2 quality planes its not so much a problem... P-51D level... it takes a little more research :)

Yo-Yo isn't satisfied with guessing :)

Yep, data surces are complicated, even were they are good because you don't know how that info were taken 70 years ago, so, why not simply (not so simple, I know) copy available airworthy aircraft? Everyday more and more wardbirds are in flight condition and that would eliminate any doubts about data. I don't know but, wasn't P-51 made that way?

 

S!

I dont know how the P-51D was developed, but I imagine that it used testing data from way back when, I think most of the US planes you can find complete wind tunnel test data for. I think you can use currently flying planes for some info, but for some things, nothing short of a wind tunnel will help you out... least that is my understanding... most WWII birds probably havent been loaded into a wind tunnel recently :)

Edit: And when I say most US planes have wind tunnel test data available I dont mean on the net necessarily... but with research and searching the proper archives...

Just out of curiousity I did some searching and found some aerodynamic wind tunnel data for the P-47D and the P-38F, just a thought.

 

I'm certain there would be major holes such as dynamic derivatives but those can be determined through analysis...not the best but better than nothing.

 

I love the idea of modeling older aircraft since you don't have to worry about modeling the flight controls system for those aircraft since it was all controlled directly by the pilot.

Yes, as I said the US planes are some of the easiest to find data for. Will the work you are doing with the F-16 translate over to prop planes?

Sounds like you need to hang out with Yo-Yo and geek out over all this stuff lol... most of the time he just makes my head spin lol.

I am collecting data for some German aircraft among others.

I may be completely off base here, I'm no mathematician or aircraft engineer..

 

but if wind data is what devs need, would a scale model od the airplane help?

I guess airplane drawings of these rare planes are more available than wind tunnel data, if it even exists.

So one could build a CAD model of the airplane and have it 3d printed (resolution measured in microns) and use it to obtain wind tunnel data?

I would have to think that the model would have to be very good, very detailed and then the person would have to be able to have the funds to rent a wind tunnel :) But I dont know....

I would think so yes...nominal aerodynamic equations are the same generally.

 

What changes is the driving data, which can be obtained fairly easily through analysis or wind tunnel data. By analysis is fairly easy since these aircraft used, for the most part, typical NACA airfoils.

 

What I see being fun to model is the control effectiveness delta due to the propulsion system. Typically that isn't a concern in modern day jets since the propulsion flow is aft of the surfaces, but for older aircraft the prop flow would have a huge bearing on the behavior of the aircraft.

 

Boy would I love to have a peek at the P-51D code :)

We managed to model the propwash stream including its interaction with the wing (wing downwash) and incoming airstream. If you recall how Ka-50 rotor was done you would not consider it extremely difficult for us. :)

Building the external model wouldn't be a problem, provided that the drawings are available.

Renting a wind tunnel, that I don't know:D

 

But one might be able to get more than one group interested in the project.

Just recently I've watched a National Geographic documentary, where Northrop built a full size Horton 229 replica, just to see how stealth it really was.

 

Anyway, my head is already spinning so I'm gonna leave it at that...

Saw that show as well, very cool...

Interestingly enough I was able to find small scale Bf-109 tests fairly easy, but full scale test data is apparently better in the long run.

P-51D set a very high bar, I think releasing something less than that would be tough for them to swallow.

Pardon the lazy question, but is there a publicly available SDK, anyone?

SDK for maps is supposed to come after EDGE is done and released with Nevada. As for planes and such, most 3rd Party people are finding their own way with help from ED devs as far as I can tell.

If you look in the API directory of DCS World you will see a skeleton example, essentially no documentation. I'm still clumsily making my way by a ton of trial and error. I don't really have a contact at ED that could help me and I don't want to bother them if they don't want to be nagged about it. For now I'm doing my best to figure it out as much as I can and hoping to report my results. Would love to get direct help from an ED person if you guys know of someone who is willing to be bugged :)

Maybe start with a PM to Wags, maybe he can help you find someone to bug :)

 

 

 

Did you use nominal prop effect equations or used an analysis tool to perform this?

We performed the same method that gave good results in Ka-50 - full prop blade element method. This method gives propwash stream parametres as well. Now the trick is to calculate how this stream interacts with the airframe, wing and empennage.

The method gives P-factor moment and transversal force as well.

And finally the method even allows to have live behaviour at seized engine when the prop stopped.

Generally the history of ED research works went on a spiral. Many years ago the first prop was modelled and a piston engine. Then Ka-50 went in production and got enhanced rotor grown from the prop and turboshaft growing from the piston engine at high price of day-and-night work :).

A-10 got its turbofan derived from Ka-50 engines (the same math but more complicated).

Ka-50 downwash model finally gave P-51 model and a little downshifting of gas-turbine engine gave V1650-7.

I'd appreciate it if Google invents a Yo-Yo translator. :D

 

Just curious if you ever gave your math teacher a heart attack? He sees you come in class and his migraine instantly kicked in. Were they afraid of you? :D

No, frankly - we all were afraid of him :) he had very loud hoarse voice and all pupils starting from elementary school knew it very well... he was a vice-schoolmaster and provided Ordnung.

But he was a great man and a good teacher.

That is awesome, for the blade element method did you sectionalize the prop or model each prop as a single blade? Do you run this blade element model in real-time or did you pull parameters out after performing high fidelity analysis?

 

For our helo, I'm debating on whether to model it via disc map model or blade element model and whether to use uniform inflow behavior or variable and my concern with the trade-off is whether the sim will be able to handle blade element with variable inflow without dropping the FPS to a slideshow

 

Also, do you know what update rate the sim runs at, is it static, or is it variable, and what happens to the simulation when it over-runs it's allowed run rate? Thanks Yo-Yo!

Yes, the blade is divided to several parts as it was done in Ka-50 because each part has its own linear velocities, its own induced velocity, etc.

In helicopter rotor model the first step is to get a field of induced velocities around the disc area then to calculate individual blade movement (flapping, hunting) in detalized model. The forces/moments then are collected from each blade element.

This model is a good compromise between accuracy and processor-friendly computation.

If you mean time discretisation - it's even.I would not comment the timing organisation in the project but you can see what happens if modelling over-runs its rate if you use time acceleration. Stutters... video frames is dropped out of the queue.