Version 8.50

Versions 8.50 is the next major functional release of X-Plane. The releases have been getting bigger and farther apart.

X-Plane 8.50 is the most carefully-tuned and powerful release we have ever had! New features are:

A-I PLANES HAVE FULL FLIGHT-MODELS:

This one is HUGE: ALL the aircraft in the X-Plane world now use the EXACT SAME FLIGHT-MODEL CODE, and your plane, and others, can have weapons systems with proper guidance and countermeasures!

This is more amazing than you might think: It USED to be that the OTHER craft in the X-Plane world tooled along simple, straight lines, obviously following a very simplified model... you could tell the other planes were really fake. When you would fly formation with them, they always went perfectly straight, never moving with the air, and never maneuvering realistically. This was pretty weak.

Now, all that is changed: The VERY SAME FLIGHT MODEL CODE that drives YOUR airplane now drives ALL the planes... and you can have up to TWENTY planes in the sky with you now. This means the other planes fly as realistically as yours, right down to rocking and rolling in turbulence, turning and climbing and descending realistically, and moving with the wind. Formation flight with them is now accurate, right down to getting in their wake turbulence. (As well, they can get in yours, and you can watch them roll and buffet as they fly through your turbulence).

To see this in action, go to the "Other Aircraft and Situations" windows in the "Settings" menu... crank in maybe 10 planes, and set them all as BLUE team, and set YOUR plane (the very top-left check boxes) as RED team. (If you want to live, do NOT let any of the other 10 planes be FIGHTERS! You can guess why. Select other planes with the little gray box beside the airplane name, same as always.) Now, select each of the OTHER 10 or so planes to be of similar performance to YOUR airplane. Are you in an airliner? Then select airliners or other hi-subsonic planes as the other planes. Are you flying a General Aviation plane? Then select slower other planes.

Once you have done that, close that window and get your plane in flight at some medium speed and altitude on autopilot. Let it fly for 15 minutes or so. Go get a drink maybe. Come back after maybe 15 minutes and switch to the external circling view ('|' key) and use the shift-arrows to circle around... see anything interesting? Since you have selected a team for those planes that is different than your team, they want to chase you down. If you had chosen any of them as being fighters... well... try that if you like. Now hit the '/' key to show flight model. Now turn on some turbulence in the Set Weather window. Now you will begin to understand the amount of math that is going on here.

Now, go back to the "Other Aircraft and Situations" window and UN-CHECK the TEAM check boxes for all the other planes. Since they are not on a team opposing you, they will no longer chase you down. Close the window and try to fly behind them... can you get in their wake turbulence? Get in the F-22 and find an airliner at 35,000 feet.. Can you intercept him? Fly in his wake? Can you get in a helicopter and intercept a slow-moving Cessna? Can you see how his wake interacts with your rotor? (Not as much as with the wings on a plane, thanks to the high blade loading and hi speed of a helo rotor, but the effect is still there!)

OK, now that you are in a fighter, and can see how to make OTHER planes fighters, and see how to put different planes on different teams, you can guess where this is going, yes? Grab the "Japanese Anime" in the "Science Fiction" folder for your plane and set about 5 or 6 other planes in the "Other Aircraft and Situations" window and set them all to be fighters (F-4, F-22, Japanese Anime... whatever). Set them all to be on a different team than you. (Remember, if you have NO team selected for a plane, then it will wander aimlessly. Select a team to make it aggressive, chasing down anyone NOT on it's team!) Now that you have the OTHER planes on the red team, and YOU on the blue team, close the window and go flying, and good luck. If you are a girly-man, then set half the other planes to be on YOUR team, so the artificially-intelligent planes will fight EACH OTHER... you can fly around and watch them fight!

Now, to add to the fun, we have a handful of new weapons-systems switches that you can put on the panel (all in the 'weapons' folder as accessed by the Panel-Editor in Plane-Maker). As well, you can add the 'console' instrument in the 'Weapons' folder to your instrument panel... all weapons on your plane will show up there, and you can click on weapons to select them. As well, the HUD will show a rectangle to indicate your target when air to air guns or missiles are armed, and a circular projected-path indicator will show up on your HUD when bombs are armed. Arm missiles or guns and use the { } keys to cycle through targets... selected targets will turn red on your moving map, and guide the target rectangle on your HUD.

Ok so that is how you shoot others.. but how do you defend against others shooting you? Chaff and flares! Grab the chaff and flare buttons in the panel-editor from the 'weapons' folder so you can mouse-click to deploy them, or just assign joystick buttons to deploy them. Select the amount of chaff and flares you have to deploy in the "Systems" window in Plane-Maker. Flares confuse heat-guided missiles, chaff confuses radar-guided. You can open weapons up in the 'Edit Weapons' window in Plane-Maker to see if missiles are heat or radar-guided, and open the 'Default Weapons' window in Plane-Maker to see what weapons various planes have. (The fighters and Japanese Anime are the armed airplanes).

Based on the type of weapon the that is being fired at you, you should decide whether to deploy chaff or flares. (Note: A rapid beeping indicates that someone has a radar-lock on you: a good time to deploy chaff... though someone (either AI plane or multiplayer opponent) could easily keep a radar lock on you for hours at a time if they are just following you around, and seeing as how chaff disperses and becomes useless in a few moments, being too quick to deploy chaff could negate any advantage it may have given you). The Japanese Anime fighter in the 'Science Fiction' folder has all this stuff... assign a joystick button to 'Flares' and switch to an external view while you pop them.. looks kind of cool. Turn on other planes and set them to other teams than you to fight against artificially-intelligent airplanes. Use multiplayer to play against friends, using all of these systems. Design your OWN fighters with these systems... no need to be content with what's out there now.

Another weapons type: LASER weapons.: Throw a laser on your plane and shoot down you friends in a multiplayer game... or any other plane in the sky! My "Japanese Anime" has a laser now... arm it by turning on the GUN switch.. and fire with the space bar or joystick button. This simulates mock aerial combat where you can chase each other around with lasers to simulate guns.

NOTE: X-PLANE DOES NOT SIMULATE DEATH OR DESTRUCTION, SO X-PLANE IS NOT REALLY A COMBAT SIMULATOR. TO AVOID THE VIOLENCE OF A COMBAT SIMULATOR, BOMBS HAVE NO EFFECT ON ANYTHING ON THE GROUND AT ALL... THEY DETONATE AND SMOKE SO YOU CAN SEE WHERE THEY HIT, BUT THEY DO NOT ACTUALLY DAMAGE ANYTHING ON THE GROUND. AS WELL, AIRPLANES ARE NOT DESTROYED BY BEING HIT. IF YOU ARE HIT WITH A MISSILE, GUN, OR LASER OF ANOTHER PLANE, YOU WILL PUFF-SMOKE AS IF YOU WERE IN A TRAINING EXERCISE, AND YOUR ENGINES WILL BE SHUT DOWN TO LET YOU KNOW YOU ARE HIT. THIS OCCURS BOTH WHEN PLAYING AGAINST THE ARTIFICIALLY-INTELLIGENT PLANES, AND YOUR FRIENDS IN MULTIPLAY MATCHES. YOU AND YOUR FRIENDS CAN NOW ENGAGE IN MULTIPLAYER COMBAT IN X-PLANE IN ANY AIRCRAFT YOU CAN DESIGN, WITH THE UNDERSTANDING THAT HITS AGAINST YOUR FRIEND WILL SHUT HIS ENGINE DOWN AND CAUSE HIM TO PUFF SMOKE, MUCH LIKE A 'RED-FLAG' STYLE TRAINING EXERCISE WHERE FRIENDS COMPETE IN AERIAL COMBAT, BUT ACTUAL DESTRUCTION OR DEATH DOES NOT OCCUR. WE WANT TO SIMULATE THE COMPETITIVE ASPECTS OF AERIAL COMBAT, MUCH LIKE IN A RED-FLAG EXERCISE, WITHOUT SIMULATING THE DESTRUCTIVE ELEMENTS.

TIRE-MODELS ARE NOW RACING-ACCURATE

I have now improved the tire dynamics according to the theory of tire dynamics presented in (automotive) racing literature. You may not NEED tire dynamics good enough to handle automotive racing physics, but X-Plane has them now anyway.

For sideforce, the model provides a sideforce that builds up to peak as the slip angle of the tire approaches 10 degrees, as in reality. Then, as in reality, the tire shifts from static to kinetic coefficient of friction as the total required force exceed the available friction and you enter a skid. Remember, in reality, a tire can NOT put out as much SIDE force if it is also being asked to put out a LONGITUDINAL force!

...So this math does consider the braking, driving, and side forces on the tire, so if you are in a tight turn and hit the brakes, the total required force to turn and brake at the same time will exceed the total available tire friction and you will transfer to kinetic coefficient of friction and enter a spin. For longitudinal force, you have rolling friction, but transfer to static friction as the brakes engage, and kinetic coefficient of friction if they lock.

All of this is very simple and common, but X-Plane now takes it to the next level: X-Plane can now handle locked brakes and spinning tires, with the longitudinal and side force vectors able to handle any skid angle and any tire rotation speed (in any direction), always opposing the molecular bond between the rubber and the road, no matter what direction the bond is dragging across... Now here is where it gets complicated... the direction of this bond is NOT simply equal to the sliding direction of the tire!

Why? Because the SPINNING of the tire changes the direction of this bond as well! This is why tires lose their ability to steer when they are locked (skidding, not turning) but why front-wheel drive cars can still turn under full power even though the front tires are skidding, but DRIVING the car! (but not locked, STOPPING the car).

Now, you may have to think about that one a moment, but:

1. If a front wheel drive car has the steering wheel hard over to the side with the front wheels SKIDDING AND LOCKED, then the wheels will provide ZERO turning ability! You might THINK that turning the steering wheel will make some difference if the front wheels are locked, but you would be wrong. When the rubber is just dragging down the road with no tire rotation, it makes absolutely no difference at all what direction the tire is facing: it's just a dragging piece of rubber.
   
   
2. But if those front wheels are SPINNING MADLY UNDER POWER, then they still DO provide turning ability since they are dragging their bond ahead and in the direction of the steering wheel input! To imagine this, just imagine a front wheel drive car STOPPED, but with the front wheels turned off to the side a healthy dose and the wheels spinning madly under full power. Clearly, the car WILL accelerate OFF TO THE SIDE, thus providing turning ability of sorts: Turn the wheel left, and the tires drag the front of the car to the left. Turn the wheel right, and the spinning tires will drag the front of the car off to the right. So you have two cases of a front-wheel drive car with skidding front wheels, but totally DIFFERENT steering dynamics!
   
   Why? Because the friction between the rubber and the road always opposes the direction the rubber is being dragged across the pavement... and you need to look at the tire sideslip angle AND the tire rotation speed and direction to resolve in which way this force acts. The tricky part is that no matter the sideslip angle, skidding speed, and tire spin speed, the total force the tire puts out (sum of ALL directions!) can never exceed the available friction. This is why cars can not ACCELERATE very strongly when in a tight turn: the tires are already near their maximum friction pulling the car around the turn, so very little friction is left to accelerate or brake. This is why it is easy to spin out a Corvette... put the car in a tight turn so the tires are near their maximum friction: then add judicious power and the torque on the wheels requires more friction to resist tire-spin... friction that is not available because the tires were putting out maximum force just holding the car in a turn. Since the friction is not available, the rear tires spin. This transitions them from static (lots) to kinetic (little) friction, initiating the (very violent and fun) spin.

Try this in a front-wheel drive car and it is different story: When you add power the tires spin madly and transfer from static down to kinetic coefficient of friction, but since the rubber on those front tires is being dragged across the road in the desired direction of travel, very little happens in the way of spin-entry... those tires are just dragging you along in the direction you are pointing the wheel.

Anyway, all of this is now simulated in X-Plane, and even though you do not have the ability to actually DRIVE the wheels with engine-torque, the physics are there, and still apply even when the wheels are just rolling or locked, as can happen in the sim. Turn your airplane and hit the brakes while turning, and the braking wheels may go over their max available friction and the spin-entry begins... it can happen in an airplane just like it does in a car. (The difference is that the airplane has the big vertical stabilizer which provides a huge aerodynamic stability, making spins much less likely, especially at high speeds, where aero forces dominate. Of course, the vertical stab does not help you out so much at low speed, where the gear forces dominate).

OK, while I was at it with the tire-modelling, I decided: "Why stop there?" and made a REALLY nice new anti-lock-braking-system model. This model actually applies and releases the brakes to keep you right on the ragged edge of your available friction, and you can really feel the brakes clamping and unclamping right at their limit, complete with the resulting steering instability and little skid near the end as the wheels lock for the last little bit of the stop... the whole 9 yards!

Now, to give the best surface for exercising this model, if airport the flattening is turned off then the airports follow the terrain contours perfectly... unlike previous versions where the pavement might not quite follow the terrain. Now, the "pavement" is now perfectly "draped onto" the ground, just paving a real runway.

ALL-NEW ENGINE-TRANSMISSION SETUP!

Go the 'Engines' screen in Plane-Maker and then go the 'Transmissions' tab. In this screen, you pick the number of transmissions your plane has.

Enter

If you want, design a plane with 3 engines 7 props. Or 1 prop. Or 9 engines. Or 1. It doesn't matter. Just specify all the engines and props you want, and link them together however you want in the 'Transmissions' window.

Also specify if each prop is free-wheeling (can continue to coast even if the engine is seized or failed or otherwise spinning slower than the prop) or whether it has a direct connection to the engine, so the engine is dragged along by the prop when power is reduced.

BIRD-FLOCKS:

X-Plane had helicopters, Seaplanes, and artificially-intelligent Air Traffic Control well BEFORE Microsoft Flight Sim, and they came along after us with their imitation every time. Now, we are beating them AGAIN. We now have: FLOCK OF BIRDS!

Is simulating flocks of birds silly? Well, I used to think so, until I was running my Cirrus (in reality) up to take-off speed to go flying and a huge flock of birds suddenly shot up out of the grass right beside the runway and dashed over the runway right in front of me. They were in front of and above me, and I figured I just MIGHT be able to fly through a hole in the flock and get through in one piece, but I yanked the power and slammed on the brakes to abort the take-off and avoid the collision. It was EXACTLY like a drag race: FULL POWER to 100 and then yank the power and slam on the brakes.. REALLY fun.. and, if you have seen what happens when a bird comes at a windshield before, you realize it was a very good idea to lay on the brakes and stop rather than have an in-flight collision with a bird.

Now, how does this correlate to X-Plane? Well, go to the "Rendering Options" screen and turn ON the "Flocks of birds" option. Then, go flying. You might get lucky for one take-off. Or maybe 10. Or maybe 20. But keep flying.. soon enough, you will see a bunch of little white dots in your path during low-altitude flight around the airport. My advice: Fly right into that flock of little white dots. What's the WORST that can happen? ;-)

RE-ENTRY COMPUTER:

New autopilot mode selector: RE-ENTRY! Do this:

• Get in my MegaHyperSonic ("Austin's Designs" folder).
• Use the planet map place it over Australia.
• Use the "Low Enroute" map to place at 400,000 ft, 14,000 knots, heading 45 degrees.
• Dial KEDW into the FMS.
• Turn OFF all the engines.
• Hit the ENT (re-entry) autopilot button on the autopilot.
• Dial in 450 knots into the autopilot speed selection window.
• Sit back while the plane flies a re-entry and takes you to edwards.

How does this work?
It is a lot more complicated than you think... you can NOT just "glide home"... here is why:
When you are high up in space, you are going 17,000 mph with nothing at all to slow you down... there is no air so slow you. When you are down low in the atmosphere you are going maybe 1,000 mph and decelerating hard... the air is thick down there.

When you are up high in space, you MUST go fast, because if you were slow, you would simply plummet (no air to lift with) and not be able to pull up in time once you finally got into the atmosphere When you are down low, you MUST go slow, because hi speed (anything like orbital speed) would rip the plane apart. So you have to gradually slow down as you go down, going fast up high, and slow down low.

Here is why this is hard, though: When you are in the first 85% of the re-entry, you are way up in space covering maybe 250 miles per minute... An error in descent of even ONE MINUTE will put you 250 miles off course... which will take maybe half an hour to correct when flying down low. Since even the tiniest slip-up in your navigation when moving FAST will take a long time to correct later on when moving SLOW, you need to avoid any error at all in the early part of your approach, where you are covering ground really fast. (tiny mistake now = huge correction later).

The problem is, in space, with the engine shut down, you have almost no ability to maneuver, so it is very difficult to nail the re-entry corridor! Now, in theory, you can say "all right, I will just ease it down slow into the atmosphere, slowing down as I descend, so I never overspeed the plane". But in the early part of the re-entry, even the TINIEST amount of lift WILL push you back into space, because thanks to the centrifugal force of orbit, the plane will stay in the air with ZERO lift (centrifugal force is holding you up at that point, no lift is needed!) Because orbital centrifugal force will hold you UP, so even the tiniest amount of lift will fling you right back into space, you need to find a way to add DRAG (to slow the plane) WITHOUT adding any LIFT at all (which would pop you right back into space).

How do you do this? By BANKING. Put the plane in a 90-degree bank and pull on the stick and you can get plenty of drag to slow the plane, but the lift of the wings is NOT pulling
you up into space because the lift is only pulling you sideways, thanks to the fact that you are in a 90-degree bank.

Remember, though, that any navigation error you make here by going off-course will be 50 times harder to correct later on when you are down in thick air, hardly moving. Basically, the way the atmosphere is laid out, almost ALL of it is below about 50,000 feet, even though SOME of it goes up to 500,000 feet. This means that almost all of the air will be encountered in the last 10% of the descent. This means that almost all of your deceleration will occur in the last 10% of the descent. This means you will come screaming in and in and in and in and the suddenly STOP right at the end.

The problem with this is that since you are stopped at the end (very low speed below 50,000 feet), any error you made getting to that last 50,000 feet of atmosphere cannot be easily corrected... the tiniest error at the beginning of the approach will have you come down in Cleveland rather than Edwards, and that will take forever to make up by flying down low, and is of course impossible to make up without starting up the engines, which may not have any fuel.

So, how do you fly the approach? By easing down into thicker air little by little as you slow down, banking to bleed off energy without climbing, switching your bank angle from left to right a lot to keep from getting off course, and choosing an altitude to give you a deceleration that will bring you to a stop just as you reach Edwards.

• The HIGHER an altitude you choose, the LESS air drag there is, and the less deceleration you will have, and the more likely you are to overshoot.
• The LOWER an altitude you choose, the MORE air drag there is, the more likely you are to come up SHORT of your target!

So how do you choose your altitude?
Well, look at the re-entry instrument I have thoughtfully added to my MegaHyperSonic EFIS right under the artificial horizon: It gives the deceleration (in G) needed to come to a stop just as you hit whatever destination is dialed into your GPS!

Is the DESIRED deceleration at 0.5 G, and your CURRENT deceleration at 0.2 G? OOPS! You are not slowing down enough! You will overshoot Edwards and wind up in the Atlantic (not Pacific) Ocean! You need to descend into thicker air to slow down more!

How do you do that?
Well, enter a HIGHER number into your autopilot airspeed entry when in RE-ENTRY autopilot mode and watch the plane descend to try to get a higher airspeed. It does NOT descend because it thinks it will speed up by descending... nothing could be further form the truth! You are already going so fast that you will not gain any noticeable speed at all by descending a mere 200,000 feet... the reason that descending will give you a higher INDICATED airspeed as that you will have exactly the same REAL speed, but it will be in thicker air, so it will INDICATE a higher speed on the airspeed indicator (remember, the airspeed indicator measures pressure on the airplane.. it is basically an indicator of the square root of dynamic pressure, or pressure of wind blowing against the airplane). This, of course, will result in more aerodynamic drag, which will slow you down faster, which will cause you to come down somewhere in the USA rather than overshooting to the Atlantic ocean.

So you have to remember it like this: your REAL speed does NOT change except over the course of maybe 30 minutes or an hour. You cannot change your real speed. You have to accept that. The inertia is just too great. Your only hope at managing the flight is to control the drag on the plane by controlling your INDICATED airspeed. And you control the INDICATED airspeed NOT by speeding up or slowing down (you can't) but by going higher or lower, into thinner or thicker air. The more you want to slow down, the more you push the nose down.

That bears repeating: IF YOU WANT TO SLOW DOWN, THE LOWER THE NOSE AND DESCEND, TO GET A HIGHER INDICATED SPEED.

This is opposite from everything you have learned, but you must understand it to say "Gee, I am too fast, and I will overshoot the entire North American Continent. I must slow down. So I must lower the nose into thicker air which will slow the plane. So I must a higher number into the re-entry autopilot speed, so the autopilot will dive me down into thicker air to get a higher indicated speed, to give me more drag, to slow me down."

Everything is backwards, but if you understand it, you will be able to do a re-entry every time, and bring it from Australia to Edwards Air force base, right down to the runway, without ever starting the engines.

I can do it. Can you?

VISUAL IMPROVEMENTS:

• New better-looking lights for the airplanes, objects, airport runways, EVERYTHING. These new lites are better looking and the light disc that we had before is now FASTER as well! Taxi right up to the runway lights... not too bad!

• New sky-colors to give better sunsets and day and evening lighting, as well as refined lighting from the sun. The water also reflects the sun colors, to give really realistic water appearance, especially around sunset. Place aircraft by airport to KAVX. Switch to '|' view. Zoom out with shift-minus key and shift arrows to move around. Set the time of day to around sunset and circle around to see the cool water effects.

• As well, the moon is now actually 3-D as well. This moon should always have lighting acting on it that is perfect for the current sun and moon locations. And we have new refinements in our orbital rendering... stars, clouds, and planet visibility are all more accurate.

• We also have up to 3 cloud layers now. This applies to manual selection, rendering, real-weather... everything! Try setting 3 different broken layers and flying around between them... pretty fun. While working cloud-like stuff, we improved smoke and contrails from the aircraft as well.

• Now we have moving cars on the roads.

• Sun glare considers obstructions from buildings and terrain... whatever might be in the way.. fly low under the buildings at sunset and look out the side window to see the sun flickering behind the buildings, like sun flickering through the trees when you drive.

• YOU CAN NOW MOVE AROUND INSIDE THE AIRPLANE! It's the coolest thing... open the Bombardier in the Seaplanes folder and hit control-o. Now look around the cockpit with the mouse. Got it? Ok, look straight ahead with the mouse now and then hit the a/s/d/w/r/f keys... COOL! Hit control-o again to get out of that mode.

As well:

• Better orbital view rendering.
• Better looking water.
• Faster scenery load time... and 3-d objects won't disappear briefly during load.
• Totally redone airport pavement and runway and taxi signs and lights.
• A bunch of new OBJ commands for scenery authors to let them do better animation and airports.
• New airport layout spec. http://www.x-plane.org/home/robinp/Apt850.htm
• New frigate and carrier and oil rig and sailboats sailing around by Christiano Maggi, with F-18's on the carrier by Barry Leger.