Aircraft takeoff issues

[KaRRiLLioN 0]

I've gotten permission from USMarine to make some modifications to the F15E. I'm trying to make it takeoff a little easier and make it a bit more maneuverable as well. I've been changing some stuff in the config and also the model trying to get this thing to even take off now.

I tried copying some of the values in H&P's F18 but that hasn't helped either. It'll hit about 250ish but never take off no matter what I do unless I hit a hill or something and it launches me like a ramp, but even so it's extremely sluggish until it hits about 300kmh. Here's some of the values:

wheelSteeringSensitivity = 1.2;

aileronSensitivity = 3.25;

elevatorSensitivity = 3.1;

flapsFrictionCoef = 1.0;

turnCoef=2.8;

noseDownCoef = 0.1;

maneuvrability=60;

maxspeed=2000;

I've also tried playing around with the mass and putting a bit more mass on the rear end. I also increased max speed to 5000 and while it accellerates faster, it still won't lift off at all. Any ideas?

[[aps]gnat 28]

Im guessing, but you may want to play with these;

landingSpeed =180;

brakeDistance = 300;

noseDownCoef = 1.0;

.

[KaRRiLLioN 0]

Thanks! It's the landing speed apparently. I saw that in another thread when I was searching and I thought that I'd put it in, but must've put it into another config that I had open for an example.

[philcommando 0]

1. try inheriting from the A10 - class myaddon: A10

2. Give it  a lower mass - 100

3. Check that all the flaps selections are properly named.

4. Try lowering the speed to that of A10. There seems to be a co-relation ratio between the max speed of aircraft and the takeoff speed...eg...if maxspeed is 500, takeoff speed is to be 200, or max speed 1000, takeoff speed is to be 400.

*landing speed:- this is the speed that once the aircraft reaches, it will automatically lose thrust and react to gravity.

eg:- if the aircraft landspeed is set to 100, when turns or manovering drops to 100, it will lose height to prepare for landing, more so the AI. If landspeed set to 0, advantage is that u will never lose height but Ai will have difficulty to land

[suma 8]

I think what you see is mostly because you have the max speed set too high - the stall speed in OFP is determined as a fraction of max. speed. (You need to move faster than the stall speed is to be able to lift).

The config value landingSpeed has no influence on the actual stall speed, it only tells the AI what speed it should use when landing.

[Footmunch 0]

Guess what? Suma's right

As for the other values:

wheelSteeringSensitivity = 1.2;

- This determines the rudder effect and the turning circle. A value of around 2 is good

aileronSensitivity = 3.25;

- This determines the roll sensitivity. Value usually around 0.7

elevatorSensitivity = 3.1;

- This determines the pitch sensitivity. Value usually around 0.5

flapsFrictionCoef = 1.0;

- This determines the strength of the flaps' speed reduction/lift increase. Usually leave it at 1

turnCoef=2.8;

- Don't think this has any effect

noseDownCoef = 0.1;

- The amount the nose drops during turns. Can be used to make the plane 'heavy' in turns. Value of around .3 is good

maneuvrability=60;

- Don't think this has any effect

maxspeed=2000;

- This is the 'standard' speed. If you want higher speeds, it's better to use afterburning scripts, rather than set this too high.

One reason for the high maxspeed of the RAD F-18 is that

gearretracting=0. This means that more speed is needed to

overcome the drag of the gear being permanently down.

On PC's stuff:

Be careful setting the plane _very_ light (mass=100) - the plane

will 'recoil' from missile and AAA hits too much if the mass is this

low. Also, flaps are _always_ present on aircraft, whether you

define ls/ps klapka in the model or not.

[suma 8]

Quote[/b] ]turnCoef=2.8;

- Don't think this has any effect

maneuvrability=60;

- Don't think this has any effect

Absolutely correct. Those two entries are specific for cars/motocycles or missiles respectively, and have no effect when used in plane config.

[Trenchfeet 0]

this may not work for you as your plane is more "modern" then mine    , but try placing an extra landcontact point in that lod

You'll notice on mine i have it near the engine.It does have the desired effect of making the plane tip forward.

Perhaps placing a point near the rear somewhere may make it tilt back sooner  

It also worked very well on CSJs C-7 Caribou

[havocsquad 0]

What exactly are you doing to the F-15E?  Are you going to just add new features and trim up some crude areas?

Maybe increasing the resistance of the flaps might help the flaps provide more stability to the aircraft. A brake script/action wouldn't hurt either.

Don't forget near the engines there is an area that needs fixed, it has all the engines connected together at the end to the frame.  Unfortunately its a badly recognizable flaw.

If you need any help working on it, I would suggest you ask TomiD and Footmunch.

When you get out a beta, let me know and I'll help you tweak the plane and the .cpp.  I've have prior experience, mainly with footmunch's F-16C addon but also some other projects I can't discuss now.

Let me know what I can do.

Later,

Havoc.

[Trenchfeet 0]

something else you can try is making sure you have the landingSpeed=170; not set to low.

For some reason this also effects the takeoff?

[Shinkansen 0]

Hi,

it would be nice to know what the definition range of values like

aileronSensitivity = 3.25;

elevatorSensitivity = 3.1;

flapsFrictionCoef = 1.0;

and so on...

really is. I mean are they factors used in some formulars to determine the fly ability or do they have a range from 0 to 10 or something.

[Trenchfeet 0]

ah yeah the range is 0-10

0 meaning leass sensitivity

10 greater

(I've never tried minusing these values )

flapsFrictionCoef = 1.0;

is 0-1 (i think, you'll need to play with this value to get the best for the plane)

some extras

noseDownCoef = 0.03;

0 - >

0 = no nose down in turns

wheelSteeringSensitivity = 1.3;

1 to 1.3 for smaller planes

formationX=25;

formationZ=15;

formation grid 0 to >

unless you've made a p-47 you'll need this nameSound="plane";

brakeDistance=40;

braking ability on land 0 best higher number means the plane takes longer to stop (i assume)

[KaRRiLLioN 0]

I never realized how many more responses this thread got after I solved my issue, but I just happened across it today while searching for a way to make the "Lower Flaps" option go away on aircraft that don't have them.

Lowering the LandingSpeed value definitely made the aircraft take off much easier.  I don't know why, but it did.  I finished editing the F15E a while back and that really made a difference.

havocsquad,  I'm not doing too much to the model, but I did raise the mass quite a bit, fix up the weapons proxies, and I also put in an afterburner plus some flame effects from the engines.  I also gave the textures a "shine" and fixed up all the weapons configs to balance them out against the Mig29 that I customized a while back.

Here are some pics:  http://ofp.gamezone.cz/_hosted/karr/f15e.html

It and the mig29 can be downloaded from my website http://ofp.info/karrillion

They're in the Bootcamp modern pack.