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[Ibis]

   It's looking great Stainless, I wish had the knowledge to help.
Unfortunately I do not so I can only watch in amazement the work
of true artists.
     I can't express my gratitude to all the modders whose hard work
has given me so much pleasure over many years.
  I thank you all,
      Ibis.

[Stainless]

Proper face palm last night

On the way into work I dropped the engines into my F4. They spun up perfectly, but the instant they lit. Bang. Dead engine. Spent the rest of the journey trying to work out why.

After a long day writing network code and dealing with a proper space cadet at Sony, I sat down on the train and debugged my code.

2 minutes later. Face palm.

I use an Earth centric coordinate system. Your aircraft's position is defined by three variables. Latitude. Longitude. Radius. RADIUS..... I had put the plane at 0,0,0. The centre of the Earth.

This caused the atmosphere model to blow up and that caused the engine to blow up.

Fixed it and now I have flight controls and engines. Time to wire in all the aerodynamics and actually fly. 

By the way I have modeled all the flight control systems as separate entities. This means they can be individually damaged. Going to be interesting to make a carrier landing, at night, with no elevators.  ???

[Herra Tohtori]

If you're using a spherical model of Earth, perhaps it would be best to offset the radius value so that zero means sea level (translates to about 6400 km from center)?

Would essentially make the third coordinate human-identifiable as altitude from the idealized sea level. Just to make it more intuitive to feed in coordinates in the future. Instruments should of course show altitude MSL (barometric) and AGL (radar).


On the other hand if you plan on using more complex general shape for Earth - like an ellipsoid or even a geoid - then there may not be a good "universal" sea level to decide on.

[Fresco23]

There are no words for how wonderful this will be if you pull it off. Many thanks from a silent but watchful supporter.

[sniperton]

There are no words for how wonderful this will be if you pull it off. Many thanks from a silent but watchful supporter.

+1

[Stainless]

I managed to get the engines working yesterday. I now have thrust 

First flight is getting closer.

I need to ask you guys for advice on something though. The F4 flight model I have data for indicates it has zero induced yaw. (Yaw generated by rolling the aircraft).

This doesn't feel right to me.

It implies you can do a barrel roll and the nose will not deviate from the flight path. I could see that being correct for modern aircraft, but the F4 is an old bird. I would expect the nose to yaw a little.

Anybody got any experience flying F4's (real or simmed) and have any data?

(thanks for the nice comments, it's going to be a long crawl to get this done. However it's not the first time I have written a game all on my own)
 

[slipper]

Stainless

This sounds an amazing project mate, your obviously a very switched on person. Just wanted to wish you all the best for this, and to say we all appreciate your efforts.

 I think probably the main reason your not getting more support is that most of us don't have a clue what your on about, rather than not wanting to help mate ????

Anyway

Regards and good luck

Slipper

[Maty12]

Stainless, any thoughts on torque effect? Cause I've flown in a B-24 and a 17 and seen videos of it: They do NOT pull to either side during take offand no rudder is used during that procedure.

[rockdoon]

Stainless, any thoughts on torque effect? Cause I've flown in a B-24 and a 17 and seen videos of it: They do NOT pull to either side during take offand no rudder is used during that procedure.

Maty I have flown in one and rudder is used but not to the extent that you need in il2... anyways continueing on with this the p51 seems to lack torque... heres why I say that... I've talked to pilots of the p51 and if your on approach and need to go around you can loose controll of the aircraft due to the torque if you put the engine imediately to 100 percent

[Herra Tohtori]

Stainless, any thoughts on torque effect? Cause I've flown in a B-24 and a 17 and seen videos of it: They do NOT pull to either side during take offand no rudder is used during that procedure.

Bombers usually did three-point take-offs and landings. Keeping the tail wheel on the ground helps with keeping the aircraft lined up with the runway. Also, multi-engined aircraft are less influenced by p-factor than single-engine aircraft because the thrust asymmetry is comparatively smaller.


That said, this is a good question - how will propeller effects like helical prop wash, asymmetric blade effect, and torque be modeled...?

[Stainless]

All my engines are specified with a position.

So if an engine goes out on a multi-engine aircraft, you will notice a turning moment.

At the moment, the torque is calculated in the "thruster"

A thruster is anything that bolts onto an engine and produces thrust. So propellers and vectored thrust are the two main ones.

At the moment I am calculating the torque quite simply, it's just a function of the power required for the thruster to work and any rotational velocity. So for a propellor it's

Code: [Select]

       vTorque.X = -Sense*PowerRequired / (RPS*2.0*M_PI);

I think this may be too simple, but without data I'm working from logical reasoning and gut feeling rather than anything scientific.

Maybe once I have a couple of aircraft flying we can do some tests and see if we need to fine tune it.

[Stainless]

Is the afterburner too subtle?