Introducing the F/22 Raptor.
It appears when I previously said my last release would be my last release... I lied. Again, immense credit to GuyFolk for the foundation of this aircraft. However, almost everything has been tweaked.
- Low part count (works well on mobile and standalone VR)
- Best experienced on PCVR on high physics (flight model is more advanced)
- Weapons x2 AIM 9X and x6 AMRAAM (AMRAAMs have been given multi role capabilities for fun)
Notable achievements include:
1) Fly by wire
This version is MUCH smoother than previous versions
- Control surface deflection should multiply by the inverse of IAS squared for consistent forces
- Thrust vectoring should by multiplied by the inverse of the output thrust
- Horizontal stabilisers multiplied by cos(AngleOfSlip) for natural control in all slip conditions
- Heavily reworked and smoothed Yaw Logic using vertical stabilisers
- Separate PID controllers for Pitch and Roll axes
- Removal of AoA from Pitch PID controller makes landing and maneouvering MUCH smoother and more controllable
- Pitch PID controller now purely using Pitch input and desired PitchRate (modifiers for AoA Limit and G Limit)
- AoA Limiter override (Activation Switch 1)
- G limiter override (Activation Switch 2)
- Differential thrust available for stability and for extreme yaw maneouvers (Activation Switch 4)
- Pitch FBW Stability (Trim). Default is 0 (Range -10 -> 10). Reset button in cockpit available
- Pitch Up assistance when throttle>40% for smooth take off
- Gravity correction factors for RollRate and YawRate (Activate6). Much improved with smoothing function. Helps keep zero slip for coordinated turns or for low level high alpha turns.
2) Landing Auto Throttle
This is enabled by default. Just keep throttle at zero on approach and use the stick to adjust your glideslope. a PID controller will keep the Engines active to maintain a ~150knot approach. Flare before touch down to a Pitch Angle of ~9-10 degrees and plane will slowly kiss the runway. If flare is too aggressive, apply airbrake to slow to 140 knots to stop gaining altitude.
3) Ground stability and manoeuvrability
Use Roll and/or Yaw controls whilst on the ground. Tire slip angles are calculated to feedback to steering system for smooth steering. at higher speed whilst on the ground, control surfaces automated to provide roll stability to resist wing strikes.
4) AirBrake Function
Airbrake can be used to bleed speed but also in conjunction with full aft stick, allows temporary disabling Pitch Stability Function allowing a cobra maneouver.
6) Throttle Thumbstick Disable
Throttle control from keyboard or thumbstick is disabled by default to allow for smooth independent rudder control in VR without inadvertent engine shutoff or afterburner activation. It also allows simultaneous Throttle and air brake application for tight min radius turns.
7) Radar/Nav System
This has been incorporated into the compass for locating targets and destinations. Destinations with runways also denote the orientation of the runway. you can cycle between desination waypoints by clicking on the compass in the cockpit.
8) HUD/Display
This is purposely kept simple to be relevant in VR. A velocity vector and virtual horizons would need to be projected at a distance of infinity which is not possible (if anyone knows please chime in). So for readability and not obscuring targets, I've left the in game Gunsight/Target Lead and added only absolutely necessary items:
-IAS (knots)
-Mach
-Alt AGL (ft) numerical + graphical elements to aid landing
-Vertical Velocity (ft/s)
-AoA (visual bars that turn amber and red when AoA>35 and AoA>90)
-AoS (turn indicator at bottom of HUD)
-controls input indicator
Since last version, Slip indicator tweaked, Mach number to HUD and new turn rate indicator added (Omega symbol: degrees/sec)
The main theme in this release is the change in FBW logic. Simply have a PID controller on the stick axes (Pitch and Roll) equating the stick deflection to desired rotation speed. Tweak the logic to adjust on centre stability, then add limiters to the input mechanism rather than having multiple variables in the PID controller which can give undesired effects. For example:
1) Stick controls Pitch variable
2) New PitchX variable created to take Pitch and add modifiers (AoA Limiter, G limiter, Exponential gain etc)
3) PitchX is then passed on to the control surface, via PID controller to translate to desired PitchRate
Occam's Razor, put simply, states: “the simplest solution is almost always the best.” This definitely applies here. Please again comment for feedback or improvements. Enjoy guys!
Specifications
Spotlights
- This craft is curated
General Characteristics
- Predecessor F-22 'Raptor' update 1.11
- Successors 1 airplane(s) +7 bonus
- Created On Windows
- Wingspan 45.1ft (13.7m)
- Length 139.6ft (42.6m)
- Height 34.8ft (10.6m)
- Empty Weight 42,321lbs (19,196kg)
- Loaded Weight 57,082lbs (25,892kg)
Performance
- Power/Weight Ratio 3.282
- Wing Loading 68.7lbs/ft2 (335.3kg/m2)
- Wing Area 831.2ft2 (77.2m2)
- Drag Points 2285
Parts
- Number of Parts 466
- Control Surfaces 4
- Performance Cost 1,894
@cosman thank you. Also I'm sorry for not getting back about the G-Limiter the internet was down for awhile. But it works well! I played around with and figured out what works. Thank you so much for your assistance it is appreciated
@Wolfgang8261YT in reality, higher speed creates ram effect and thrust increases. higher altitude means less dense air which means less thrust but also less drag and the net effect is more altitude means higher ground speed up to a point when other factors are limiting (reduced lift -> need more AoA -> more drag & air too thin that engine is out of its operating window). Set the engine thrust output to a variable and do experiments with it to see the effect of IAS,GS,Altitude on thrust and also number and size of intakes. I haven't found a formula linking them yet but there was a post i remember which went into the maths of this quite well.
@cosman so the Tomcat (A) had TF-30 engines (the B variant got GE-110) but the TF-30 was absolutely horrendous at accelerating at low speed but exceeding around 600kts they started having a almost ramjet effect and could reach a speed of mach 2+ what I have a problem with is simpleplanes physics where engines very unrealistically underperform at high altitude so I found a code that basically makes the engines start at 50% capability and increase with altitude. So what happened basically I was trying to get the bad acceleration until 600kts thereabout then start really spoiling up. I modified the same code for the wing sweep and modified it and stuck it in another engine. It's still not really working tbh. It still accelerates like a rocket. I dont really know what I was asking when I started typing this. But do you have any suggestions?
@cosman thank you! I'll play around and see. Yes there were a whole bunch of wings around the place I couldn't find all of them plus I'm not the smartest when it comes to stability so I sorta left them. But yes there were alot. As for the CG would maybe sticking a fuselage block (with amplified weight) on a piston that moves it backwards according to wing sweep help? I'll have to test that it just came to me. So yeah I'll play around with it and see what works thank you! And yeah I have a potato phone so I gotta make it as performance light as I can lol
@Wolfgang8261YT https://www.simpleplanes.com/a/91aRHE/Grumman-F-14A-Tomcat-ie. Use this as a starting point, I did a few things: first adjusted the CG rearward which makes it much smoother to control at low speed. you might want to simulate something to move CG backward when the wings sweep if you want smooth high speed control but thats more complicated. there were wayyyy too many wings confusing the picture and so I disabled Pitch control on so many wings that had control surfaces and made only the rear horizontal stabilisers the only parts to control Pitch. Another problem is that Symmetric airfoils peak lift at ~15 deg then stall, so to prevent unnatural behaviour you need to clamp their rotation limit to both individual airfoil angle + aircraft's angle of attack. I only did something very brief and you can play around with this some more if you want. Finally the wing loading was way too low so I adjusted "liftScale" on most wings to 0.2. Also beacon light for AB seems like a good idea for low performance cost!
@cosman https://www.simpleplanes.com/a/lGn9ye/Grumman-F-14A-Tomcat-WIP that's it. And I rlly hope you like the afterburner :/ everything took me so damn long to do
@cosman lots of big brain stuff lol. Anyway I'll post it unlisted and link you. Thank you so much! And yes, flying while bobbing up and down is extraordinarily annoying
@Wolfgang8261YT link me a jet and I'll try and modify my version to smooth it out. essentially, you want to forget about measuring G to then adjust the planes pitchrate. by the time the gforce builds from the angle of attack you pull, its too late and you get oscillations. You need to calculate expected G's from a function of PitchRate and TAS (I did the math and labelled it VertG in this plane). Also getting an oscillation free plane is sooooo involved and best way is to have a CG close to centre of lift so that the slightest Pitch input keeps the plane rotating even when you release the stick. Then you can rely on the flight computer inertial measurements (PitchRate etc to provide stability and you tune the strength you need).
@cosman hello I dont know if you remember me I've been of for a long while but anyway I have a question. So basically I'm working on remodeling a Tomcat (the A variant) and I have been dealing with so much problems in my attempt to make it fairly realistic, but one of my biggest problems is a G-Limiter. I've tried a few I found on the site but once I start really accelerating it starts shaking like crazy and and pretty much becomes uncontrollable. I dont know if you can help? Thank you
@GhostMach Appreciate it!
you literally cooked this to perfection, can you make thebnext one have stronger engines?