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friction

Posted: Fri Dec 23, 2011 3:56 pm
by Boom
I need friction. I dont have friction. My plane acts like the x-15. any idea why and how to fix it?

Re: friction

Posted: Fri Dec 23, 2011 3:58 pm
by Raven
Copy paste the stock F-16 .dat and replace it with your planes .dat.

Re: friction

Posted: Fri Dec 23, 2011 5:12 pm
by Shiny Rice
Friction?

Re: friction

Posted: Fri Dec 23, 2011 5:14 pm
by Raven
What he means is dynamic friction, skippers X-15 acts as if it was just slideing through the air without any friction, and when you try to hit brakes, cut throttle, and lower gear.. the aircraft remains a constant speed..

Re: friction

Posted: Fri Dec 23, 2011 5:21 pm
by Shiny Rice
Ah.

Re: friction

Posted: Fri Dec 23, 2011 5:52 pm
by Shutter
Go look at the .dat info page in tutorials. You've got a drag coefficient, so use it. ;)

Re: friction

Posted: Fri Dec 23, 2011 10:49 pm
by Boom
Already tried that. I made the gear have extreme drag, but it only cuts the speed instantly down to 400kts when engine is off and stops having an effect.

Re: friction

Posted: Fri Dec 23, 2011 11:07 pm
by Shutter
That's silly. Why would you use the value for when the gear is down to try and dictate your entire drag coefficient?

Use the flaps and pitch effects on drag as well as critical speed and cruising speed to get it right. Look at a dat that works and start tweaking values.

And I have said this many times before and I'll say it again: if you want your shit answered then give us a lot of information. You could post your dat and explain what sort of flight performance you're looking to get out of it. Help us help you because no one should have to waste their time guessing what your problem is from a vague explanation and then somehow deducing a solution for you. :|

Re: friction

Posted: Sat Dec 24, 2011 2:36 am
by Dragon029
Also look at changing your wing area; that'll have an affect on drag at any AoA other than 0.

Re: friction

Posted: Sat Dec 24, 2011 3:07 pm
by Boom
wing area 50m^2, no drag still.
This was based on a stock rafale's dat.
Most of the dat:
CATEGORY UTILITY
AFTBURNR TRUE #HAVE AFTERBURNER?
THRAFTBN 30000t #THRUST WITH AFTERBURNER
THRMILIT 0t #THRUST AT MILITARY POWER
WEIGHCLN 100t #WEIGHT CLEAN
WEIGFUEL 100t #WEIGHT OF FUEL
WEIGLOAD 0t #WEIGHT OF PAYLOAD
FUELABRN 5t #FUEL CONSUMPTION WHEN USING AFTERBURNER
FUELMILI 0kg #FUEL CONSUMPTION AT MILITARY POWER

COCKPITP 0.0m 0.3m -0.2m #COCKPIT POSITION
LEFTGEAR -1.2m -1m -3m #LEFT LANDING GEAR POSITION
RIGHGEAR 1.2m -1m -3m #RIGHT LANDING GEAR POSITION
WHELGEAR 0.0m -3m -1.15m #WHEEL POSITION
ARRESTER 0.0m -1.70m -5.57m
MACHNGUN -0.8m 0.70m 2.10m #MACHINE GUN POSITION
GUNINTVL 0.04
SMOKEGEN 0m 0m -3m #SMOKE GENERATOR POSITION
VAPORPO0 0m 0m 0m #VAPOR POSITION (Wings Swept Back or no-VGW)
VAPORPO1 0m 0m 0m #VAPOR POSITION (Wings Spread)
HTRADIUS 3.5m #OUTSIDE SPHERE RADIUS


STRENGTH 3000

CRITAOAP 32deg #CRITICAL AOA POSITIVE
CRITAOAM -25deg #CRITICAL AOA NEGATIVE

CRITSPED 0.9MACH #CRITICAL SPEED
MAXSPEED 3.0MACH #MAXIMUM SPEED

HASSPOIL TRUE #HAS SPOILER?
RETRGEAR TRUE #HAS RETRACTABLE LANDING GEAR?
VARGEOMW TRUE #HAS VARIABLE GEOMETRY WING?

CLVARGEO 0.0 #EFFECT OF VARIABLE GEOMETRY WING FOR Cl
CDVARGEO 4.0 #EFFECT OF VARIABLE GEOMETRY WING FOR Cd
CLBYFLAP 0.1 #EFFECT OF FLAP FOR Cl
CDBYFLAP 0.2 #EFFECT OF FLAP FOR Cd
CDBYGEAR 3.5 #EFFECT OF GEAR FOR Cd
CDSPOILR 2.0 #EFFECT OF SPOILER FOR Cd

WINGAREA 54m^2 #WING AREA

MXIPTAOA 23.0deg #MAX INPUT AOA
MXIPTSSA 5.0deg #MAX INPUT SSA
MXIPTROL 360.0deg #MAX INPUT ROLL

REM CPITMANE corresponds to Spring Constant K
REM CPITSTAB corresponds to Damper Constant B
REM To be critically damped, B=2*sqrt(K)
REM 2% Settling Time=??

MANESPD1 40kt #MINIMUM MANEUVABLE SPEED
MANESPD2 80kt #FULLY MANEUVABLE SPEED
CPITMANE 10.0 #PITCH MANEUVERBILITY CONSTANT
CPITSTAB 1.0 #PITCH STABILITY CONSTANT
CYAWMANE 5.0 #YAW MANEUVABILITY CONSTANT
CYAWSTAB 3.0 #YAW STABILITY CONSTANT
CROLLMAN 3.0 #ROLL MANEUVABILITY CONSTANT

CTLLDGEA TRUE #CONTROL LANDINGGEAR
CTLBRAKE FALSE #CONTROL BRAKE
CTLSPOIL 0.0 #CONTROL SPOILER
CTLABRNR FALSE #CONTROL AFTERBURNER
CTLTHROT 0.0 #CONTROL THRUST
CTLIFLAP 0.0 #CONTROL FLAP
CTLINVGW 0.0 #CONTROL VARIABLE GEOMETRY WING
CTLATVGW FALSE #CONTROL AUTO VARIABLE GEOMETRY WING

POSITION 0m 3ft 0m #POSITION
ATTITUDE 45deg 0deg 0deg #ATTITUDE
INITFUEL 75% #INITIAL FUEL
INITLOAD 0.0t #INITIAL PAYLOAD
INITSPED 0.0MACH #INITIAL SPEED

REM the slots and all would go here
INITIGUN 0

NMTURRET 25
A WHOLE BUNCH OF TURRETS THAT ONLY SHOOT FORWARD

REM ClZero,CdZero is fixed by Cruising condition
REFVCRUS 0.9MACH #CRUISING SPEED
REFACRUS 40000ft #CRUISING ALTITUDE
REFTCRUS 0.8 #CRUISING THROTTLE SETTING

REM ClSlope,CdConst is fixed by Landing condition
REFVLAND 90kt #LANDING SPEED
REFAOALD 10deg #LANDING AOA
REFLNRWY 2000m #RUNWAY REQUIRED TO STOP
REFTHRLD 0.30 #LANDING THROTTLE SETTING

AUTOCALC

Re: friction

Posted: Sat Dec 24, 2011 9:13 pm
by Midnight Rambler
Try having a fiddle with these settings
.dat topic wrote:CLVARGEO 0.0 - The increase in lift when the variable sweep wing is out

CDVARGEO 0.0 - The increase in drag when the variable sweep wing is out.

CLBYFLAP 0.0 - The increase in lift when the flaps are fully deployed

CDBYFLAP 0.0 - The increase in drag when the flaps are fully deployed

CDBYGEAR 0.0 - The increase in drag when the landing gears are deployed.

CDSPOILR 0.0 - The increase in drag when the spoiler is deployed.

Re: friction

Posted: Sat Dec 24, 2011 10:21 pm
by Boom
seems to be connected to mach 5 speeds. It was a missile, just lowered it to a more realistic mach 3 and made acceleration time more than 1 second.