My own flight sim

[TMac3000]

A couple of weeks ago, I started working on the first flight simulation to come from my own two hands This is a project I started on before, but I either lost interest in it or got distracted by other projects, along with various other excuses.

The idea is, I hope, a unique one: a sim of a generic antisubmarine helicopter. My inspiration came mostly from three sources: a very old naval warfare computer game called Strike Fleet, a little-known British helicopter training sim called Merlin, and the scenes in Tom Clancy's novel Red Storm Rising, which featured a helicopter crew hunting Soviet submarines that were threatening a convoy to Europe.

For now, my focus is on realism tempered by simplicity. So far I have implemented rotor-torque and semi-realistic hover behavior. I plan to add ground effect, but I don't really understand the more complex stuff like vortex ring, retreating blade stall, etc, so I will probably leave those things out.

Today I got the hover model in the lateral plane to a point where I was happy with it, so I am considering that part to be finished. Either tonight or tomorrow, I will start work on the longitudinal plane. When I finish the flight model altogether, I want to start working on jazzing up the cockpit, (like adding numbers to the instruments:embarrassed, so let's just say I'm a loooong way from being finished. I may ask you guys for mathematical or programing advice from time to time.

The language is Q-Basic. Yes, I know it's ancient, but I cut my teeth on BASIC, and trying to learn C++ just frustrates the hell out of me. Look for Subhunter by the end of next summer!

 

[Urwumpe]

I remember doing a football game in QBasic...but that was soooo 80s.

 

[Blacklight]

Once you get it finished, you should post it in the forum over at www.subsim.com. They would LOVE to see your work over there. There are a lot of us sub-hunting "Dangerous Waters" players over there. :thumbup:

 

[Xyon]

And here too, I'm a sub-simmer myself from time to time. I do keep a collection of sub sims lying around, but from the other perspective, like Silent Hunter. I like this concept and wish you luck with the project.

 

[N_Molson]

I confirm, Dangerous Waters is one of my favorites :thumbup:

 

[Blacklight]

Dangerous Waters is one of those programs that never, EVER, leaves my hard drive. :thumbup:

 

[Urwumpe]

Yeah, I can't say I am done with Dangerous Waters. A worthy successor to 688i Hunter/Killer.

 

[TMac3000]

Once you get it finished, you should post it in the forum over at www.subsim.com. They would LOVE to see your work over there. There are a lot of us sub-hunting "Dangerous Waters" players over there. :thumbup:

I'll keep that in mind, thanks:tiphat:

 

[Tommy]

Retreating blade isn't that complicated in concept, althouh accurately modeling it may not be simple. A simplified workaround might be to have the copter roll (towards the side where the rotor blades are moving toward the rear), and the amount of roll force would be related to the airspeed. THis would mean some "stick" would be required to keep level, and at some velocity "full right" stick (assuming the rotor turns counter clockwise if seen from above) would be required to maintain level flight - and at airspeeds higher than that the copter would roll to the left no matter what you do. The relation between speed and roll should be somewhat exponential, not linear. It should be possible to tweak a fairly simple equation to provide the desired effect - just use the copters "Max speed" as the point where "full right stick" is required for balance.

 

[jedidia]

The language is Q-Basic.

waitaminit... that thing still exists? I remember giving up on it because it seemed to have a code limit (don't know how much anymore, but I reached it...). Then again, that was... errr... over 15 years ago? maybe someone improved it in the meantime...

 

[4throck]

QBasic? Can it handle cockpit graphics? 3D world?
I once programed a Pacman game with it and importing graphics was really complicated...

I'd say go for Javascript instead. It's easy to understand and there's good support for it. Also, it has better performance and it runs directly from your browser. Also, it can be used to drive 3D real world graphics via GoogleEarth plug-in, just by outputting the heli coordinates to a specified variable. Not to undermine your efforts so far, but please consider it.

Here's a nice example: http://www.aiguilles-chamonix.com/3d/

 

[TMac3000]

QBasic? Can it handle cockpit graphics? 3D world?
I once programed a Pacman game with it and importing graphics was really complicated...

I'd say go for Javascript instead. It's easy to understand and there's good support for it. Also, it has better performance and it runs directly from your browser. Also, it can be used to drive 3D real world graphics via GoogleEarth plug-in, just by outputting the heli coordinates to a specified variable. Not to undermine your efforts so far, but please consider it.

Here's a nice example: http://www.aiguilles-chamonix.com/3d/

Probably my first incarnation will have some kind of wire-frame graphics. It would be ugly, but enough to understand what you are looking at. And the aircraft will be over the water most of the time anyway

I haven't gotten that far yet. I'm finished with the (fairly simplistic) flight model, and now I'm working on the cockpit. Getting the numbers on the heading gyro to rotate around the dial has proven to be ((pare(nthetical he)ll)), and some of the hairiest coding I have ever done:compbash2:

 

[ddom2006]

Yeah, I can't say I am done with Dangerous Waters. A worthy successor to 688i Hunter/Killer.

Sub-Sim? How detailed is it, does it have a plot or is it free-roam? Etc. Couldn't find these details glancing briefly at the website, sorry if I missed it...

 

[TMac3000]

Finished with the six main instruments in the cockpit! And I must say, it came out looking pretty sharp I wanted to post a screenshot, but Q-Basic wont let me take one

The altimeter, airspeed, and vertical rate indicator were pretty easy. The attitude indicator and compass were the most challenging.

Next step will be adding waypoints and navigation.

 

[Urwumpe]

Sub-Sim? How detailed is it, does it have a plot or is it free-roam? Etc. Couldn't find these details glancing briefly at the website, sorry if I missed it...

The level of detail is similar to 688i, but doesn't stop at a single submarine class. For the 688i in Dangerous Waters, compared to 688i H/K, there are only subtle differences.

Also, you can pilot:
- Russian Akula class submarines
- Russian Kilo class submarines
- US Seawolf class submarines
- P3 Orion maritime patrol aircraft
- SH-60B ASW helicopters
- Oliver H. Perry Frigates. (Yes, the Helen Keller class. The weakest combatant to pilot)

The graphics are vastly improved, you can do missions below ice (very much fun). The campaigns are structured like 688i, but you can select different vehicles for each missions to play them from different perspectives. What is missing is the role-playing game character of having a single boat and letting crew gain experience and the boat upgrades. But I think it is well compensated.

 

[TMac3000]

Can anyone suggest a simple way to code ground effect? I had a method that sort of worked, but it was buggy on descent: the helicopter would keep "bouncing" up and down when I got to ground effect altitude.

 

[Urwumpe]

Can anyone suggest a simple way to code ground effect? I had a method that sort of worked, but it was buggy on descent: the helicopter would keep "bouncing" up and down when I got to ground effect altitude.

Isn't it caused by interaction between wing airflow and ground? You could include it into the lift function by querying vessel altitude and pitch angle.

 

[TMac3000]

Okay, got ground effect working, but the VVI needle still wobbles like crazy if you hit ground effect with a certain descent rate. No longer worried about that Moving on, probably to retreating blade stall. Yes, I know I said I wasn't going to simulate that, but Tommy's post and some of my research convinced me that it's within my reach.

 

[TMac3000]

Okay, suppose I'm flying a helicopter well within ground effect at high speed (i.e. 100 knots or so). Aside from the obvious stupidity and danger of such a move, would there be any unusual flight effects other than ground effect?