Special Situations in X-Plane 10

Using an Instructor Operator Station (IOS) for Flight Training
An Instructor Operator Station is a sort of console used by a flight instructor or someone standing in for an instructor. This console can be used to fail multitudes of aircraft systems, alter the weather and time of day, or relocate the aircraft. The IOS can be run either on the same computer as the simulator (using a second monitor), or it can be a separate computer which connects to the computer used as the simulator either via a local network or over the Internet.

Using one computer it is possible to draw whatever view of the aircraft or panel you wish in addition to an Instructor Operator Station (IOS), assuming your graphics card has two video outputs. To enable output of an IOS on your second monitor, open the Rendering Options from the Settings menu. There, check the &ldquo;draw IOS on second monitor on same card&rdquo; box (located in the Special Viewing Options portion of the window). A second window will appear displaying your view of your aircraft, and when you close the Rendering Options window, you will have a standard Local Map dialog box open in the other. Then, simply ensure the IOS box is checked in the upper right of the window and you will be ready to go. Use the button on the left to load different aircraft, relocate the aircraft, fail systems, and alter the weather for the &ldquo;student&rdquo; pilot.

Note that the mouse cannot be used to fly the aircraft when running an IOS on a second monitor.

Alternatively, to use a second computer as an IOS. To do so, launch X-Plane on both computers and open the Net Connections dialog box (found in the Settings menu). There, select the IOS tab. You need only tell the &ldquo;master&rdquo; machine (the one running the simulator, used by the student pilot) and the IOS how to &ldquo;talk&rdquo; to one another. On the master machine, check the box labeled IP of single student instructor console (this is master machine). Then, enter the IP address of the computer used as the IOS. Correspondingly, on the computer used as an IOS, check the box labeled IP of master machine (this is instructor console) and enter the IP address of the student&rsquo;s computer.

In both cases, it should not be necessary to change the port number from 49000.

Flying Gliders
To fly a glider, such as the ASK 21 included with X-Plane 10, you will want to first be towed aloft by another aircraft. To do so, first load your glider as usual (using the Open Aircraft dialog box), then open the Aircraft & Situations dialog box. Here, you have two options. The Glider Tow button will load another aircraft (by default, the Stinson L-5) to which your glider will be attached. This aircraft will pull yours along behind it, and you will be able to release the line connecting you to the towplane at your desired altitude. On the other hand, the Glider Winch button will set up a stationary winch on the ground which will quickly pull in a wire attached to your glider, which you will release once you are 1500 feet or so above the ground. In either case, you can release the tow line by pressing the space bar.

When using the towplane, you will start behind the plane with its engine running and ready to go. Releasing the glider&rsquo;s brakes (using the &lsquo;b&rsquo; key by default) commands the towplane to take off, dragging your glider with it.

The towplane, once in flight, will take the glider as high as you likes. While being carried up to altitude, though, you must keep your glider in formation behind the towplane. Pressing the space bar will release the line between the aircraft, allowing you to soar freely.

Notice, of course, that until you have unhooked yourself, the tow rope connecting your glider to the towplane is attached to your nose and the towplane&rsquo;s tail. X-Plane models the real physics of this situation, so if your glider pulls left, right, up, or down, it will drag the towplane&rsquo;s tail in that direction. This could result in simply pulling the plane off course, or ultimately in dragging the plane into a stall or spin. If that happens, things will get very complicated very quickly&mdash;the towplane (which will likely be crashing) will be dragging the glider with it! The dynamics of the resulting crash are interesting if nothing else.

According to the FAA Glider Handbook, a glider pilot should keep the glider in one of two positions when being towed to altitude. It should either be in a &ldquo;low tow&rdquo; position, wherein the glider is just below the wake from the towplane, or it should be in a &ldquo;high tow&rdquo; position, just above the wake from the towplane. Hold this position carefully to keep from dragging the towplane around!

A glider pilot must watch the wind and the slope of the terrain carefully to hold inside the upward-moving currents of air, using the lift of the air flowing up the mountain slope to hold the craft aloft. With a good 25-knot wind set in the simulator, you can get a nice, free elevator ride to 10,000 feet when flying along the windward side of a nice, steep mountain. This is called ridge lift.

X-Plane will also model the columns of rising hot air, called thermals, that are useful for prolonging a glider flight. To turn on the thermals, open the Weather dialog box from the Environment menu. Select the set weather uniformly for the whole world radio button, then drag the thermal coverage slider up&mdash;15 percent coverage or more makes for a nice flight. A 500 ft/min thermal climb rate is fine, but you can raise that value, too, if you like. Additionally, as you&rsquo;re starting out in gliders, you may want to keep the various wind speed, shear speed, and turbulence sliders set to minimum.

Now, to take full advantage of both ridge lift and thermals, gliders have a unique instrument known as the total energy variometer. This indicates your glider&rsquo;s rate of climb or descent. You can see the visual representation of this instrument in the panel (it is labeled &ldquo;Total Energy&rdquo;); if the needle is above the center of the dial, you are climbing (perhaps due to ridge lift or a thermal), and if it is below the center, you are falling. Even better, you can flip on the switch labeled &ldquo;Audio&rdquo; in the instrument panel to get auditory feedback from the variometer. If it is beeping, then the aircraft is in a nice updraft from the air following the terrain. Circling in that area will let the glider ride the climbing air to altitude. When the variometer is emitting a steady tone, the craft is in descending air&mdash;the glider has been blown to the wrong side of the mountain, and a crash will follow soon if you do not find a way out of that area!

To land the glider, simply circle down to runway level. The trick is to approach the runway with just enough speed to set the craft down safely. Remember, pulling the speedbrakes in can help slow the craft down, but if it doesn&rsquo;t have enough speed to reach the landing strip, the glider has no way of generating thrust. Ideally, you will reach the runway at just above stalling speed, but it&rsquo;s always better to have too much speed (which you can burn off using the speedbrakes) than too little.

Flying Helicopters
The following is a description of how helicopters are flown in the real world, along with the application of this in X-Plane. Note that helicopters are loaded in X-Plane just like any other aircraft, using the Aircraft menu&rsquo;s Open Aircraft dialog box. Note also that you can move to the helipad nearest you at any time by opening the Aircraft menu, clicking Aircraft & Situations, and pressing the Helipad Takeoff button.

All manner of different helicopter layouts can be found in reality, but we will discuss the standard configuration here&mdash;a single overhead rotor with a tail rotor in the back. Here&rsquo;s how this works: First, the main rotor provides the force needed to lift the craft by continuously maintaining the same rotor RPM for the entire flight. The amount of lift generated by the main rotor is only varied by adjusting the blade pitch of the main rotor blades.

So, imagine the one-and-only operational RPM of a helicopter is 400 RPM. When the craft is sitting on the ground, the rotor is turning 400 RPM, and the pitch of the rotor&rsquo;s blades is about zero. This means that the rotor is giving about zero lift! Because the blades have zero pitch, they have very little drag, so it is very easy to move them through the air. In other words, the power required to turn the rotor at its operational RPM is pretty minimal. Now, when the pilot is ready to go flying, he or she begins by pulling up on a handle in the cockpit called the &ldquo;collective.&rdquo; When this happens, the blades on the rotor go up to a positive pitch. All the blades on the main rotor do this together at one time&mdash; &ldquo;collectively.&rdquo; Of course, they are then putting out a lot of lift, since they have a positive pitch. Equally apparent is the fact that they are harder to drag through the air now, since they are doing a lot more work. Of course, since it is a lot harder to turn the blades, they start to slow down&mdash;if this were allowed to happen, it would be catastrophic, since the craft can&rsquo;t fly when its rotor isn&rsquo;t turning! To compensate, at that point any modern helicopter will automatically increase the throttle as much it needs to in order to maintain the desired 400 RPM in the rotor.

To summarize, this is the sequence for getting a helicopter in the air in X-Plane:
 * 1) While on the ground, the collective handle is flat on the floor. This means the rotor pitch is flat, with minimum drag and zero lift. In X-Plane, a flat collective corresponds to the throttle being full forward, or farthest from the user. The automatic throttle in the helicopter is obsessively watching the rotor&rsquo;s RPM, adjusting the throttle as needed to hold exactly 400 RPM in the example above. On the ground, with the collective pitch flat, there is little drag on the blades, so the power required to hold this speed is pretty low.
 * 2) When you decide to take off, you do so by raising the collective up&mdash;that is, by pulling it up from the floor of the helicopter. In X-Plane, this is done by easing the throttle on a joystick back down toward you. This increases the blade pitch on the main rotor and therefore increases its lift, but it also increases the drag on the rotor a lot. The rotor RPM begins to fall below 400 RPM, but the auto-throttle senses this and loads in however much engine power it has to in order to keep the rotor moving at exactly 400 RPM.
 * 3) More collective is pulled in until the blades are creating enough lift to raise the craft from the ground. The auto-throttle continues adding power to keep the rotor turning at 400 RPM no matter how much the collective is raised or lowered.

Once the craft is in the air, the first-time helicopter pilot&rsquo;s first crash is no doubt beginning. This inevitability can be delayed for a few moments using the anti-torque pedals.

The main rotor is of course putting a lot of torque on the craft, causing it to spin in the opposite direction (because of course for every action there is an equal and opposite reaction&mdash;the rotor is twisted one way, the helicopter twists the other way). This is where the anti-torque pedals come in. The rotational torque on the helicopter is countered with thrust from the tail rotor. Just push the left or right rudder pedal (such as the CH Products Pro Pedals) to get more or less thrust from the tail rotor. If rudder pedals aren&rsquo;t available, the twist on a joystick can be used for anti-torque control. If the joystick used does not twist for yaw control, then X-Plane will do its best to adjust the tail rotor&rsquo;s lift to counter the main rotor&rsquo;s torque in flight.

Incidentally, the tail rotor is geared to the main rotor so that they always turn in unison. If the main rotor loses 10 percent RPM, the tail rotor loses 10 percent RPM. The tail rotor, like the main rotor, cannot change its speed to adjust its thrust. Like the main rotor, it must adjust its pitch, and it is the tail rotor&rsquo;s pitch that is being controlled with rudder pedals or a twisting joystick.

Once the craft is in the air and the collective pitch of the main rotor is being adjusted (in X-Plane, using the joystick throttle), try holding the craft 10 feet in the air and adjusting the tail-rotor pitch with the anti-torque pedals (i.e., rudder pedals or a twisting stick) to keep the nose pointed right down the runway. From here, the joystick should be wiggled left, right, fore, and aft to steer the helicopter around.

Here is how this works: If the stick is moved to the right, then the rotor blade will increase its pitch when it is in the front of the craft, and decrease its pitch when it is behind the craft. In other words, the rotor blade will change its pitch through a full cycle every time it runs around the helicopter once. This means that it changes its pitch from one extreme to the other 400 times per minute (7 times per second) if the rotor is turning at 400 RPM. Pretty impressive, especially considering that the craft manages to stay together under those conditions! Now, while it seems that the right name for this might be the &ldquo;helicopter destroyer,&rdquo; the fact that moving the stick sends the blade pitch through one cycle every rotation of the rotor blades means we call the control stick the cyclic stick. So, we have the collective, cyclic, and anti-torque controls.

Let&rsquo;s talk more about the cyclic. When the stick is moved to the right, the rotor increases pitch when it is in the part of its travel that is in front of the helicopter. This will increase the lift on the front of the rotor disc, causing it to tilt to the right, since the gyroscopic forces are applied 90 &deg; along the direction of rotation of the gyroscope. Now that the rotor is tilted to the right, it will of course drag the craft off to the right as long as it is producing lift.

The fascinating thing is that the rotor on many helicopters is totally free-teetering; it has a completely &ldquo;loose and floppy&rdquo; connection to the craft. It can conduct no torque left, right, fore, and aft) to the body of the helicopter. Maneuvering is only achieved by the rotor tilting left, right, fore, and aft, dragging the top of the craft underneath it in that direction. The helicopter body is dragged along under the rotor like livestock by a nose-ring, blindly following wherever the rotor leads.

Once you master hovering in place, push the nose down to tilt the rotor forwards. The lift from the rotor acting above the center of gravity of the aircraft will lower the nose of the helicopter, and the forward component of lift from the rotor will drag the craft forward as it flies along.

Flying the Space Shuttle
Read this chapter before attempting Space Shuttle landings in X-Plane if you want your virtual pilot to live!

The first rule of flying a glider&mdash;quite unlike flying a powered plane&mdash;is this: Never come up short. When bringing a powered plane in for landing, if the pilot thinks the craft will not quite make it to the runway, it is no big deal. She or he just adds a bit more power to cover the extra distance. If a little more speed is needed, it is again no problem&mdash;just add power.

Gliders play by a different set of rules, though. There is no engine to provide power, so when setting up a landing, a pilot must be sure to have enough altitude and speed to be able to coast to the airport, because if s/he guesses low by even one foot, the craft will hit the ground short of the runway, crashing. Gliders must never be low on speed or altitude, because if they ever are, there is no way of getting it back&mdash;a crash is assured. (Thermals, or rising currents of air, provide the exception to this rule. These can give efficient gliders enough boost to get the job done, but thermals will typically provide less than 500 feet per minute of vertical speed&mdash;not enough to keep even a lightweight Cessna in the air!)

Now, with the Space Shuttle, it is certainly true that the aircraft has engines&mdash;three liquid-fuel rockets putting out 375,000 pounds of thrust each, to be exact. (To put this in perspective, a fully-loaded Boeing 737 tips that scales around 130,000 pounds, so each engine of the orbiter could punch the Boeing straight up at 3 Gs indefinitely. That is not even considering the solid rocket boosters attached to the Shuttle&rsquo;s fuel tank that provide millions of pounds of thrust!)

So, the Space Shuttle has engines; the problem is fuel. The orbiter exhausts everything it&rsquo;s carrying getting up into orbit, so there is nothing left for the trip down. Thus, the ship is a glider all the way from orbit to its touch-down on Earth. With the final bit of fuel that is left after the mission, the orbiter fires its smaller de-orbit engines to slow it down to a bit over 15,000 miles per hour and begins its descent into the atmosphere.

So, if you want to fly the Space Shuttle, and the Space Shuttle is a glider from the time it leaves orbit to the time it touches down on Earth, you must bear in mind the cardinal rule of gliding: Always aim long past the landing point), not short, because if ever you aim short, you are dead, because you cannot make up lost speed or altitude without engines. Aim long since the extra speed and altitude can always be dissipated with turns or speedbrakes if the craft winds up being too high, but nothing can be done if it comes up short.

In observance of this rule, the Orbiter intentionally flies its glide from orbit extra high to be on the safe side. But there is one problem. It would appear that if the Orbiter flies its entire approach too high, it will glide right past Edwards. In reality, this doesn&rsquo;t happen for one reason. For most of the re-entry, the Shuttle flies with the nose way up for extra drag, and it makes steep turns to intentionally dissipate the extra energy. The nose-up attitude and steep turns are very inefficient, causing the Shuttle to slow down and come down to Earth at a steeper glide angle. If it ever looks like the Orbiter might not quite be able to make it to the landing zone, the crew simply lowers the nose to be more efficient and level it out in roll to quit flying the steep turns. This makes the Orbiter then glide more efficiently, so the crew can stretch the glide to Edwards for sure. The extra speed and altitude is the ace up their sleeve, but the drawback is they have to constantly bleed the energy off through steep turns (with up to 70 &deg; bank angle!) and drag the nose up (as high as 40 &deg;!) to keep from overshooting the field.

We will now walk through the re-entry process from the beginning as it is done both in the real Shuttle and in X-Plane.

After de-orbit burn, the shuttle heads for the atmosphere at 400,000 feet high with a speed of 17,000 miles per hour and a distance of 5,300 miles from Edwards (equivalent to landing in the Mojave Desert after starting a landing approach west of Hawaii&mdash;not a bad pattern entry!). In reality, the autopilot flies the entire 30-minute re-entry, and the astronauts do not take over the controls of the shuttle until the final 2 minutes of the glide. The astronauts could fly the entire re-entry by hand, but it is officially discouraged by NASA, for obvious reasons. These speeds and altitudes are way outside of normal human conception, so our ability to &ldquo;hand-fly&rdquo; these approaches is next to nil.

During the first one hundred NASA Shuttle missions, the craft was hand-flown for the entire re-entry only once, by a former Marine pilot who was ready for the ultimate risk and challenge. In contrast, users flying the Space Shuttle in X-Plane will have to complete the entire mission by flying by hand.

Walkthrough
To open the Space Shuttle for a re-entry flight into the atmosphere, go to the Aircraft menu and select Aircraft & Situations. In the window that opens, click the Space Shuttle: Full Re-entry button. X-Plane will load the craft at around 450,000 feet, in space, coming down at a speed of Mach 20. Control will be limited in space (the craft is operating off of small reaction jets on the Orbiter, set up as &ldquo;puffers&rdquo; in Plane-Maker), but once the shuttle hits atmosphere, there will be some air for the flight controls to get a grip on and the craft will actually be able to be controlled. The ship will first hit air at about 400,000 feet, but it will be so thin that it will have almost no effect.

The airspeed indicator at this point will read around zero&mdash;interesting, since the craft is actually moving at over 17,000 mph. The reason for this is that the airspeed indicator works based on how much air is hitting it, just like the wings of the Orbiter do. In space, of course, that&rsquo;s very little. The indicated airspeed will build gradually as the craft descends. Under these conditions, even though the Shuttle is actually slowing down, the airspeed indicator will rise as it descends into thicker air that puts more pressure on the airspeed indicator. This oddity of the airspeed indicator, though, is useful, since the air is also putting more pressure on the wings. This means you should get some help with your research paper and the airspeed indicator is really measuring how much force the wings can put out, which is really what a pilot is interested in here.

Restated, the airspeed indicator indicates the craft&rsquo;s true airspeed times the square root of the air density. It indicates lower speeds in thin air, but the wings put out less lift in thin air as well, so the airspeed indicator works very well to tell the pilot how much lift can be put out by the wings.

If the airspeed indicator reads more than about 250 knots, the wings have enough air to generate the lift to carry the aircraft. If the airspeed indicator is showing less than about 250 knots, then the wings do not have enough air hitting them to lift the Shuttle, so it is still more or less coasting in the thin upper atmosphere, where the air is too thin to do much for controlling flight.

As the airspeed indicator on the HUD gradually starts to indicate a value (as the aircraft descends into thicker air), it means the craft is starting to ease down into the atmosphere at 15,000 mph like a sunburned baby trying to ease into a boiling-hot Jacuzzi&mdash; very carefully and very slowly. Remember, if the craft was going 15,000 mph in the thick air of sea level, it would break up into a million pieces in a microsecond. The only reason it survives at 15,000 mph up here is the air is so thin that it has almost no impact on the ship. Again, the airspeed indicator tells how much the air is really impacting the craft; 250 knots is a &ldquo;comfortable&rdquo; amount. The trick is to get the craft moving much slower than 15,000 mph by the time it gets down to the thick air of sea level&mdash;and to have it doing so at Edwards Air Force Base. This is what the re-entry is for, to dissipate speed while descending so that the Orbiter is never going too fast for the thickness of the air that it is in. It should only descend into the thicker air once it has lost some speed in the thinner air up higher. The whole thing should be a smooth process wherein the ship doesn&rsquo;t get rammed into thick, heavy air at too high a speed.

Now, as the Orbiter begins to touch the outer molecules of the Earth&rsquo;s atmosphere, you will notice a slight ability to fly the ship as some air begins to pass over the wings. At the same time, the HUD should begin showing speed. Notice the picture of the Orbiter on the right-hand EFIS display. The Atlantis already has this display retrofitted over its old steam gauges (the EFISs from the Atlantis are modeled very accurately in X-Plane&mdash;astronauts could use it for familiarization for sure). Both the Orbiter and the path down to Edwards should be visible. The goal is to stay on the center path. If the craft gets above it, it is either too fast or too high and might overshoot the landing. If it gets below it, it is either too slow or too low and might not make it.

Remember that the line is drawn with a large margin for error, so if a pilot stays on the line, he or she will have plenty of extra energy. Getting below the line a little will only tap into the speed/altitude reserve. Getting below the line a lot will keep the craft from reaching Edwards.

The Orbiter must stay near the center green line. This green line represents the desired speed for the early part of the re-entry, the desired total energy for the middle part of the re-entry, and the desired altitude for the final phase of the re-entry. This is the way NASA set up the EFIS. If the craft is too fast or too high (meaning it is above the center line) then it is time to dissipate some energy. Put the Shuttle in a steep bank, pull the nose up, and hang on!

The real Orbiter will have it nose up about 40 &deg; and be in a 70 &deg; bank to try to lose energy while moving at 14,000 mph, glowing red hot, hurtling through the upper atmosphere on autopilot, and leaving a ten mile-long trail of ionized gas behind it while the astronauts just watch.

Go into some steep turns to dissipate energy as needed to keep the ship from going above the center green line. Look at the little blue pointer on the far left-hand side of the far right display. That indicates how high the nose is supposed to be. The green pointer is where the nose is now-they need to match. The pointers just to the right indicate the desired and current deceleration. These indicators, though, will not be used to fly by. Look at the little pointer up top on the horizontal scale. That is the computer&rsquo;s estimation of how much bank angle the craft probably needs to stay on the center green line. Pilots should follow the computer&rsquo;s recommendation or their own intuition for how much bank to fly, but they must certainly keep the nose up (in order to stay in the upper atmosphere) and fly steep banks to dissipate the extra speed and altitude. It might be tempting to just push the nose down if the craft is high, but don&rsquo;t. The aircraft would drop down into the thick air and come to an abrupt stop from the tremendous drag, keeping it from ever making it to Edwards. It would wind up swimming in the Pacific somewhere around Hawaii.

Now, as the pilot makes those steep turns, the aircraft will gradually be pulled off course. For this reason, the turn direction should be switched from time to time to stay on course. Turn left awhile, then right, then back to the left again. This is what the real Orbiter does&mdash;it slalom-skis through the upper atmosphere at Mach 20. Watch Edwards on the center EFIS display.

As the ship approaches Edwards, right on the center green line on the right-hand display, there should be a sort of a circle out past Edwards. This is the Heading Alignment Cylinder, or H.A.C. The aircraft will fly past Edwards at about 80,000 feet, then fly around the outside of the H.A.C. like it&rsquo;s running around a dining room table. After coming around, it will be pointed right at Edwards. If the craft is still on the green line, its altitude will be just right for landing as well. In the real Shuttle, this is usually where the pilot will turn off the autopilot and hand-fly in.

The craft should now be doing about 250 or 300 knots, coming down at about 15,000 feet per minute or so (about 125 miles per hour of descent rate). Needless to say, pilots do not want to hit the ground with that 125 miles per hour descent rate. Do not aim for the runway without expecting to become a smear on it. Instead, aim for the flashing glideslope lights 2 miles short of the runway that NASA has thoughtfully provided. If they are all red, the craft is too low. If they are all white, it is too high, so the speed brakes need to be brought in. If the lights are half red and half white, the Orbiter is right on its glideslope (about 20 &deg;). Airliners fly their approach at 125 knots with a 3 &deg; angle of descent, while the Space Shuttle uses 250 knots and a 20 degree descent angle&mdash;not too unusual considering pattern-entry started west of Hawaii, actually.

To recap: the craft should be at 250 knots, on the green line, lined up with the runway. It should be facing half red, half white glideslope lights with the flashing strobes by them. This approach configuration should be held until the craft is pretty close to the ground (3 &deg; glideslope to the runway), then the descent should be leveled and the gear put down (using the &lsquo;g&rsquo; key or the mouse). Pull the nose up for a flare as the runway approaches, causing the Orbiter to touch down smoothly. Lower the nose then and hit the parachute and even the brakes if the craft will be allowed to roll out.

Now, if you can just repeat that process another hundred times in a row without a single hitch, you will be as good as NASA.

Special thanks to Sandy Padilla for most of the Shuttle re-entry information!

Flying the X-15
The North American X-15 is a rocket-powered speed demon. With a top speed of Mach 6.72 (4520 miles per hour), it is the fastest manned aircraft in the world. To begin flight, this craft is dropped, uniquely, from the B-52 &ldquo;mothership.&rdquo; Its top speed is over double that of the SR-71 (the world&rsquo;s fastest jet airplane), and its maximum altitude of over 50 miles qualifies its pilots for astronaut status.

The craft&rsquo;s absurdly high top speed requires a blast shield to be installed over one side of the windshield&mdash;without it, the windows would burn up. The X-15 pilots would fly the high speed portion of the mission with the shield on the right side, looking out the left side only. After the craft slowed down (and the left window was sufficiently charred), the pilot would jettison the blast shield and move to the right window in order to land.

To open the X-15, open the Aircraft menu and click Aircraft & Situations. In the dialog box that appears, click the Air Drop from B-52 button. X-Plane will load up both the X-15 and its drop ship (by default, the B-52). When you are ready, press the space bar to release the rocket from the drop ship. Give it full throttle, with no flaps, and watch your airspeed &ldquo;rocket&rdquo; - - - that is, until it gains enough altitude, at which point its indicated airspeed will drop to maybe 15 knots, while it is actually moving at Mach 6.

Simulating Combat in X-Plane
X-Plane is not intended to be a combat simulator. Therefore, while combat functionality exists in the form of guns and missiles, damage from weapons is not simulated realistically&mdash;getting hit will simply cause your engines to die, allowing you to glide to the ground.

Simulating combat in X-Plane involves four steps:
 * configuring your controls,
 * adding enemy aircraft,
 * equipping your own aircraft with guns and/or missiles, and
 * dogfighting.

Configuring Your Controls


In order to use your flight controls to control your weapons, either to fire them or to cycle through the currently armed weapons, open the Settings menu and click Joystick & Equipment. There, go to the Buttons: Basic tab and configure the buttons as you desire. Remember to first press the button on the joystick that you intend to assign, then select its function.

You can also assign weapons controls in the Buttons: Adv tab or the Keys tab. The &ldquo;weapons/&rdquo; category contains the relevant settings there.

Note that assigning joystick controls is especially important if your aircraft does not have controls in the instrument panel for arming weapons. If you intend to use missiles, you must assign buttons to select targets, using the &ldquo;target select up&rdquo; and &ldquo;target select down&rdquo; functions.

Adding Enemy Aircraft


To set up a combat situation, first open the Aircraft menu and click Aircraft and Situations. The bottom panel, labeled Other Aircraft Selection, is the one we&rsquo;re interested in. Set the number of aircraft (in the upper left of the box) to 2 or more. Boxes will appear below corresponding to the other aircraft, as seen in Figure 2.

Clicking the box to the left of an aircraft file name will open a standard &ldquo;Load Aircraft&rdquo; dialog box; use these boxes to load the aircraft you would like to battle.

To the right of each aircraft file is the plane&rsquo;s &ldquo;team color.&rdquo; Aircraft which have the same color will be teammates, and all other colors will be enemies. In Figure 2, &ldquo;your plane&rdquo; is on the red team, while the three other aircraft are on the green team. In this case, all three enemy aircraft will target you alone.

Having selected the enemy aircraft to fly against, you can choose their skill level, ranging from very easy to very hard, using the drop down box near the top of the Other Aircraft Selection portion of the window.

Finally, you can choose to either save the aircraft you have selected to your preferences or have them randomized at each load using the radio buttons next to the number of aircraft setting. Having set up the combatants, you can close the Aircraft and Situations window.

Equipping Your Aircraft


Many military craft, such as the F-22 Raptor, F-4 Phantom II, and Saab JA 37 Viggen come equipped with guns and missiles by default. If your aircraft does not have weapons, or if you would like to change the loadout, you can do so using the Weight and Fuel window, launched from the Aircraft menu. There, the Ordnance tab can be used to add a weapon to the aircraft&rsquo;s hardpoints (or weapon stations).

Clicking the small squares to the left of each weapon slot will bring up a dialog box to load a weapon. Opening the Weapons folder (found in the main X-Plane directory) will display a number of weapon options. For instance, in Figure 4, a GAU-8 Avenger 30mm gun is selected.



Clicking Open will arm the weapon you chose.

Arming Weapons and Fighting
With enemy aircraft in the sky, weapons equipped to your aircraft, and your joystick or yoke configured for weapons, it&rsquo;s time to dogfight. If your aircraft was designed with combat in mind, it will have a toggle for arming a weapon, and potentially a weapon rate of fire control as well. For instance, Figure 5 shows the weapons controls in the F-22 Raptor. The Raptor&rsquo;s gun is currently selected, with its rate of fire set to the maximum. Similar controls appear in the F-4 Phantom II, seen in Figure 6.

With your weapon selected, whether guns or missiles, all it takes to fire is to press the button on your joystick assigned to fire weapons.



Targeting Enemy Aircraft and Using Missiles


In order to lock on to a target using missiles, you must have a joystick or key assigned to the &ldquo;target select up&rdquo; and/or &ldquo;target select down&rdquo; functions, as described in the section &ldquo; sec:combat_configure_controls&rdquo; above. In order to usefully target, the aircraft must have either a head-up display (HUD) or moving map, and preferably both.

When enemy aircraft are nearby, you can use the target select controls to assign targets for your missiles to seek out. With a target which is not currently visible selected, the HUD will show an arrow pointing in the direction of the target, as the image on the left in Figure 7. If the active target is visible on screen within the HUD, however, a targeting reticle will appear around the aircraft, as in the image on the right in Figure 7.

In aircraft with a moving map display, there is often much more data visible than what is relevant in a dogfight. Therefore, by pressing the green buttons beneath the standard EFIS moving map, you can turn off all but the TCAS (traffic collision avoidance system) indicators&mdash;that is, the indicators for other aircraft. For instance, compare the two displays in Figure 8.





With only the other aircraft displayed on the map, it is much easier to see the location of enemy fighters and to distinguish the active target. For instance, in Figure 9, the aircraft approximately 30 &deg; to the right was selected as the target, so it is highlighted in red on the display.

Additionally, note that the dial above the moving map labeled TFC (traffic) controls the radar system&rsquo;s range. Moving the dial clockwise will increase the range, and turning it counterclockwise will decrease it. At low ranges, finer detail is available on the EFIS display.

Strategy
The key to winning a dogfight lies in creating a situation where your aircraft&rsquo;s strengths are emphasized and an opponent&rsquo;s weaknesses are exploited. This means trying to force a tight, up-close battle when flying a more maneuverable fighter than the enemy, or aiming for dive-bombs and other tactics requiring speed and weight when flying a faster, larger craft.



Additionally, do not underestimate the value of quick combat maneuvers, such as:
 * corkscrews--rolling your craft left or right while continuously varying its pitch
 * feints&mdash;rolling to one side as though to go into a banked turn (i.e., a turn with the craft on its side, while pulling back on the controls in order to pull &ldquo;in&rdquo; to the turn), but pushing the nose forward instead
 * barrel rolls&mdash;often described as &ldquo;a cross between a roll and a loop&rdquo; (see Figure 10 )

For more information on combat tactics, see the Dicta Boelcke, a list of tactics developed by World War I ace Oswald Boelcke.

Performing Carrier Operations
To begin carrier operations, select the aircraft you will use. The F-22 Raptor or the JA 37 Viggen (both found in the Fighters folder, in the Aircraft directory) are good choices. Then, open the Aircraft & Situations window and press the Carrier Catshot or Aircraft Carrier Approach buttons to set up a catapult launch from a carrier or a final approach to one, respectively.

To take off from a carrier, a few things must be done in quick succession. First, give the aircraft full throttle, and pull in about half flaps. Release the brakes (using the &lsquo;b&rsquo; key by default) to activate the catapult propelling your aircraft off the deck. From there, simply guide the craft down the flight deck and, once clear, pull the nose up. When you&rsquo;re safely in the air, bring the gear up (using the &lsquo;g&rsquo; key by default) and you&rsquo;re off.

Landing on the carrier is a bit more difficult. First, be sure you have an aircraft with an arresting hook, such as the default fighters in X-Plane.

To set up an approach to a modern carrier, such as the USS Nimitz included with X-Plane 10, bear in mind that the landing runway is angled 30 &deg; to the port (left) side&mdash;it is not straight down the flight deck like in older carriers. This change was made in order to prevent the all-too-common overruns that occurred in WWII when a landing plane crashed into the stacked line of planes at the far end of the carrier. A pilot landing on such a carrier must correct for this angling. With your ADF tuned to the carrier, then, you must wait until the ADF is pointing either 15 or 60 &deg; to the right before turning in for a landing.

When approaching the flight deck to land, a glidepath of about 3.5 &deg; is standard. At this time, the tail hook should be lowered by tapping the HOOK button, turning it green. This will allow the tail of the aircraft to catch the arresting wires on the deck. These wires will accelerate the craft from well over 100 knots down to zero in little more than a second.

Unlike in a conventional landing, there should be no &ldquo;flare&rdquo; before touching down on the carrier. Whereas, say, an airliner would raise its nose up just before touching the runway (thereby ensuring a smooth landing), a carrier approach should maintain a constant glideslope until the craft hits the deck.

Also, rather counter-intuitively, a real fighter pilot must slam the throttle to full the instant that the aircraft touches the deck. This is because, even when the pilot has done everything right, the craft&rsquo;s tail hook can bounce over the arresting wires in what is called a &ldquo;bolter.&rdquo; When this happens, the pilot must be ready to get off the deck safely and come around for another try. Don&rsquo;t worry&mdash;even when the throttle revs up like this, the arresting wires will still pull the craft down to zero velocity.

Fighting Forest Fires
In order to do water bombing on forest fires in X-Plane, load up your desired water tanker, such as the Bombardier 415 seaplane. Then, in order to increase the likelihood of encountering forest fires, open the Environment menu and open the Weather dialog box. There, click the radio button labeled set weather uniformly for the whole world. Set all cloud layers to &ldquo;clear,&rdquo; with no precipitation, and set the temperature to 70 &deg; F (21 &deg; C) or more.

At this point, you should be able to find some forest fires, especially in mountainous areas. To jump instantly to the nearest forest fire, you can open the Aircraft menu and click Aircraft & Situations. In the dialog box that appears, click the Forest Fire Approach button. Alternatively, the forest fires will show up in the X-Plane maps (available in the Local Map dialog box, found in the Location menu) as a small fire icon.

In the Bombardier 415, you will have to first scoop up water into the aircraft&rsquo;s underside. With your water payload ready to be dropped, you can assign a key (as described in the section &ldquo; sec:keyboard_shortcuts&rdquo; of Chapter ) to the &ldquo;jettison payload&rdquo; function (categorized under flight controls). Press that button to drop your load of water on the fire.

Flying in Non-Standard Gravity
You can change the X-Plane world&rsquo;s gravitational properties using the Environment Properties dialog box, which is found in the Special menu. The planet&rsquo;s gravity is calculated based on the radius and mass of the planet. This can be used for some interesting experiments.

Flying Other Special Situations
In the Aircraft & Situations dialog box (opened from the Aircraft menu), you will find a number of other special ways to take off and fly. Pressing the Grass field takeoff, Dirt field takeoff, Gravel field takeoff, or Waterway takeoff buttons will take you, in your current aircraft, to the nearest airstrip of that type. Be sure not to use the Waterway takeoff button unless you are in a seaplane!

Using the Frigate Approach, Medium Oil Rig Approach, or Large Oil Platform Approach buttons will give you excellent targets for a helicopter landing.