Chapter 2: Getting Acquainted with the Simulator
From X-Plane Wiki
Each of the X-Plane apps for Android, iPhone, iPod Touch, and Pre is built on the same framework, so flight controls and menu options vary only slightly between different versions. We’ll go through the basics of using those flight controls and menus here. Then, in each application’s own chapter, we’ll discuss things pertinent to that app only—for instance, Chapter 7, X-Plane Racing will discuss the planes found in that app, the race courses available, and how to fly the aircraft.
Remember that definitions for any unfamiliar terms may be found in the glossary.
Note: Due to the uniqueness of their flight and thus the uniqueness of their user interfaces, X-Plane Helicopter, Apollo, and Space Shuttle have their own separate manuals. These may be downloaded from the X-Plane.com website.
Basic Flight Controls
1. Throttle - Found on the left side of every flight view is a scrolling bar labeled THROT. This controls the throttle. Slide it all the way to the top of the screen for full throttle, or all the way to the bottom of the screen for none.
In some aircraft (those with thrust reversal capabilities), the throttle slider will be about 1/3 of the way up the screen by default. Dragging the slider to the top of the screen will, of course, give the aircraft full (forward) throttle. Dragging it to the bottom, however, will give it full reverse thrust, useful in slowing down after touching the ground on a landing. For a list of reverse thrust-capable aircraft, see each app's specific chapter.
2. Flap Control - The scrolling bar on the right side of the screen controls flaps. When at the top of the screen, this commands no flaps, and when at the bottom, it commands full flaps.
Note that when dragging the scroll bar controls, the box with writing on it (such as FLAPS or THROT) shows where the user has commanded the controls to be, while the other box shows where the setting is at the moment. If the user commands a quick, large movement of the controls, it will take the aircraft a second or two to meet that command.
3. Rudder Control - The slider in the bottom of the screen controls the rudder. This is used to control the aircraft’s yaw. Drag the slider to the left to turn the aircraft to the left, and drag it right to turn the aircraft right. For a visual representation of yaw, see the Flight Dynamics appendix.
4. Brakes - The button on the bottom left toggles the brakes on or off. When it is lit up, the brakes are on, and when it is off, the brakes are off.
5. Landing Gear - The button to the right of the brakes controls the gear. When this button is lit, the gear is down, and when it is unlit, the gear is up. Of course, this only applies to aircraft with a retractable landing gear.
To steer the aircraft left, tilt the iPhone or iPod left. To steer it right, tilt right. This movement—when the wings dip down or rise up while the fuselage (the main body of the plane) stays pointed in the same direction—is referred to as roll. To pull the airplane’s nose up, tilt the device back toward you, and to push its nose down, tilt the device down away from you. This movement—when the wings remain at the same attitude, but the fuselage moves—is called pitch. See the Flight Dynamics appendix for a visual representation of this.
Because the iPhone, iPod Touch & Android devices do not have a third input axis to use for yaw (as a joystick with a twisting handle does in the desktop version), X-Plane will attempt to stabilize the aircraft’s yaw for you.
Basic procedure for taking off (covered more in depth in each app’s specific chapter) is as follows:
- 1. Turn off the brakes.
- 2. Drag the flaps about 1/3 of the way down to create some extra lift for takeoff.
- 3. Slide the throttle all the way up.
- 4. Drag the RUD (rudder) slider left and right to steer down the runway.
- 5. When the aircraft reaches its takeoff velocity (which is different for every craft—heavier planes need greater speed), tilt the device back toward you, thus pulling back on the craft’s flight controls.
- 6. Once the airplane is safely in the air, drag the flaps back up to the top of the screen and toggle the gear up (if applicable).
- 7. Level the plane off once it is a few feet above the ground so that it can build up speed. This will act as a “cushion” to prevent it from stalling once it begins to climb in earnest.
- 8. Climb at around a 10 degree incline (more powerful craft can handle higher climb rates) at full throttle until the desired altitude is reached. Note that once the power is set at full, the performance of the plane (in terms of its climb rate and airspeed) is controlled by pitching the nose up and down. If its nose is pitched too high up, its speed will drop until it stalls. This can be thought of as being similar to a car trying to go up a hill—an excessively steep hill will cause the car to go very slowly and its engine to overheat.
Note: If your aircraft crashes, go into the settings menu and select either a new airport to take off from or a random flight. This will reset the airplane after the crash, giving you a brand new one to fly again.
Using the Menu and View Options
Tapping the center of the screen will cause the various menu icons to appear at the top. In most of the applications, there are two rows; the top row has six buttons, and the bottom row has two, as shown in the image below.
1. Cockpit View - This selects the default cockpit view, which is out the windshield with the head-up display (HUD). The HUD is described in detail below.
2. External View - This selects the external view. Hit that, then drag your finger around on the screen to adjust the viewing angle. To zoom out, put two fingers down far apart on the screen and drag them closer together. To zoom in, put two fingers on the screen close together and drag them apart. This is a nice way of controlling the view that is just not possible with a mouse pointer, since the simulator takes input from both fingers at once.
3. Spot View - This selects the spot view. Selecting this will give the user a stationary view from which to watch as the aircraft flies by.
4. Linear Spot View - This selects the linear spot view, where the camera takes a constant-speed trajectory to match the airplane's flight path. This is like the view of a pilot with whom the user is flying formation if that pilot were to turn around and look at the user’s airplane. This will look identical to the spot view until the user's craft changes either speed or direction.
5. Settings Menu - This opens the Settings menu, discussed in below.
6. Pause/Replay - This is the pause/replay button. When this is pressed, the replay buttons will appear, as highlighted in red in the following screenshot:
The center of these five buttons pauses the replay. The two buttons immediately to the left and right, respectively, rewind and fast-forward the replay at a slower-than-real-time rate. The two outer buttons rewind and fast-forward the replay much faster.
7. Instrument Panel - This displays the aircraft’s instrument panel. This view is described in depth in below. Note that in this view, the only menu options available are the HUD view and the pause button (both highlighted in red in the screenshots on the next page). Thus, to access the settings menu or switch to an external view, the user must first return to the HUD view.
8. Circle View - This displays the circle view. This is similar to the chase view, labeled 2 in the same figure. However, where the chase view reorients the camera to track the aircraft, the circle view keeps a fixed heading and orientation as it follows the craft.
9. Display Aerodynamic Forces - The final menu option (labeled 9 in the first screenshot in this section) will cause X-Plane to display the aerodynamic forces acting on the airplane. These are only visible when using an external view. These are a visual representation of the forces that X-Plane is calculating for each piece of the airplane. When in an external view, try maneuvering the plane around a good bit to see the little green bars move in real time. Just as in real life, it is these forces that act on the mass of the plane to accelerate it and move it through time and space—just as Newton predicted over three hundred years ago. Watch what happens as you add and decrease power, extend and retract the flaps, or slow to a stall (where the wings can no longer produce enough lift to support the weight of the plane). Cool!
The Head-Up Display in Depth
The head-up display, or HUD, allows the user to see a great deal of information regarding the aircraft's operation without sacrificing the view of the outside world.
1. Aircraft Airspeed (ASI) - The ticking tape on the left side of the screen (numbered 1 in the image above) displays the aircraft’s speed in knots. Note that this is the aircraft's indicated airspeed, not necessarily its true airspeed. This measurement comes from the airspeed indicator (ASI), which, in its simplest form, is nothing more than a spring which opposes the force of the air blowing in the front of a tube attached to the aircraft. The faster the airplane is moving the stronger the air pressure is that acts to oppose the spring and the larger the indicated speed. However, when there is little air available to "push" on that spring, the instrument will display a low number regardless of how fast the craft is moving. For instance, in the SR-71 Blackbird (found in X-Plane Extreme), the craft might be zipping along at Mach 1.5, but at an altitude of 70,000 feet, its ASI will show it moving at around 200 knots (around 0.3 Mach at sea level). Even better, in the Space Shuttle, the craft can be moving at around 17,000 miles per hour while its airspeed indicator shows zero (because, of course, there is no air at all in space).
2. Fuel Gauge - In the bottom left of the screen is a fuel gauge. When the triangle-shaped indicator is at the far right, as it is in the figure, the tanks are full. When it is at the far left, the fuel tanks are empty, and the aircraft’s engines will not be able to run.
3. Aircraft Speed (Mach) - Directly beneath the ticking airspeed indicator is the aircraft's speed relative to the speed of sound. For example, in the previous image, the craft was moving at 0.21 Mach.
4. Altitude (above sea level) - The ticking tape on the right side (number 4 in the previous image) displays the craft’s altitude in feet above mean sea level. For instance, in the image above, the aircraft was at 4830 feet above mean sea level.
5. Climb Rate (FPM) - The number directly below the altitude indicator is the craft's climb rate in feet per minute. For example, in the image above, the craft was descending at a rate of 760 feet per minute, so the number displayed was -760.
6. Attitude & Flight Path Indicator - In the center of the screen are two horizontal bars. The V-shaped bar indicates the airplane's attitude—that is, the combination of its pitch and roll. The bar with a circle in the center of it is called the flight path indicator. It represents where the plane is actually flying, rather than where it is pointed. Thus, in the figure, the aircraft is pointed straight ahead (per the V-shaped bar), but it is actually travelling a bit to the right (per the circled bar).
When the craft is taken into a 90 degree stall, the attitude indicator (the V-shaped bar) will stay momentarily at the 90 degree mark even as the flight path indicator drops rapidly. This is due to the fact that the aircraft's vertical velocity slows to zero, then becomes negative, while its nose is still pointing up. Only after the craft falls a bit will its nose be pushed down.
Surrounding those bars are lines marking degrees of pitch. For instance, in the figure, the aircraft was pitched down at around 2 degrees (indicated by the V-shaped bar), and its wings were banked slightly to the left.
Note that the craft will hold a constant altitude (that is, it will have a climb rate of zero) when the center of the velocity vector's circle is at the zero degree mark.
7. Directional Gyro - Finally, in the bottom center of the screen is a directional gyro, indicating which direction the aircraft's nose is pointing.
The Panel View in Depth
In the panel view, the aircraft's instrument gauges (or EFIS, whichever the case may be), navigation radios, and basic autopilot settings (where available) are accessible. Flying from this view requires the use of the artificial horizon. The piston-engined aircraft (that is, those with propellers) in the mobile X-Plane applications have a panel equipped with the "standard six" steam gauge flight instruments. Aircraft with jet engines, though, have an electronic flight instrument system, or EFIS.
Note: In the panel view, the only menu options available are the HUD view and the pause button (both marked with a red box in the screenshots that follow). Thus, to access the settings menu or switch to an external view, the user must first return to the HUD view.
The "Standard Six" Gauges
There are six primary instruments that have become standard in any instrument panel. Since the early 1970s, these have been arranged in a standard layout referred to as “the six pack.” In X-Plane for iPhone, iPod Touch, Android, and Pre, this standard layout has been adhered to with one exception (explained below).
1. Airspeed Indicator (ASI) - The first instrument in the top row is the airspeed indicator. In its simplest form, it is nothing more than a spring which opposes the force of the air blowing in the front of a tube attached to the aircraft. The faster the airplane is moving the stronger the air pressure is that acts to oppose the spring and the larger the deflection of the needle from which the pilot reads the craft’s speed. There are a number of ways that this reading can be thrown off (most obviously by flying at an altitude where there is little to no air), so bear in mind that this is the indicated airspeed, not necessarily the true airspeed.
2. Attitude Indicator - The second instrument in the top row (labeled 2 in the image above) is the attitude indicator, which displays the aircraft's position in space relative to the horizon. This is accomplished by fixing the case of the instrument to the aircraft and measuring the displacement of the case with reference to a fixed gyroscope inside.
3. Altimeter - The third instrument in the top row is the altimeter. This displays the aircraft's altitude (in feet above mean sea level) by measuring the expansion or contraction of a fixed amount of air acting on a set of springs. As the airplane climbs or descends, the relative air pressure outside the aircraft changes and the altimeter reports the difference between the outside air pressure and a reference, contained in a set of airtight bellows.
4. Turn Coordinator - The first instrument in the bottom row is the turn coordinator. This measures the aircraft's rate of turn. The instrument is only accurate when the turn is coordinated—that is, when the airplane is not skidding or slipping through the turn. A skid is the aeronautical equivalent to a car that is understeering, where the front wheels do not have enough traction to overcome the car's momentum and the front of the car is thus plowing through the turn. In a car, this results in a turn radius that is larger than that commanded by the driver. A slip is a bit more difficult to imagine unless one is a pilot already. It results from an aircraft that is banked too steeply for the rate of turn selected. To correct the slip, all the pilot has to do is increase back pressure on the yoke, pulling the airplane "up" into a tighter turn, such that the turn rate is in equilibrium with the bank angle.
5. Omni-bearing Indicator (OBI) - The second instrument in the second row is not the traditional directional gyro of the "standard six." Instead, to facilitate instrument flight, the directional gyro has been replaced with an omni-bearing indicator (or OBI). More information on this instrument can be found in Chapter 12.
6. Variometer - The sixth and final instrument in the second row is the vertical speed indicator, also called the vertical velocity indicator or variometer. This reports the aircraft’s climb or descent rate in feet per minute (fpm). Typically, non-pressurized airplanes will climb comfortably at about 700 fpm (if the plane is capable) and descend at about 500 fpm. Descent rates faster than this cause discomfort on the occupants which is felt in passengers’ ears. Pressurized airplanes can climb and descend much more rapidly and still maintain the cabin rate of change at about these levels, since the cabin altitude is not related to the ambient altitude unless the pressurization system fails.
Scrolling down in the panel of the piston-engined aircraft (by touching your finger on the screen and dragging it up) will show the navigation radios, as in the screenshot below.
1. Brakes - The BRAKES button functions just like the one in the HUD view—when it is lit up red, the brakes are on, and when it is dimmed, the brakes are off. To the right of this button in aircraft with a retractable landing gear is the GEAR button. When it is lit, the gear is down, and when it is dimmed, the gear is up.
2. NAV 1 Radio - The NAV 1 radio is used for navigating using a radio signal. It is tuned using the two knobs on the instrument.
3. This knob is used to tune the integer (or "counting number") portion of the frequency.
4. This knob is used to tune the decimal portion of the frequency.
To turn a knob up, tap directly above it, and to turn it down, tap directly below it. For instance, if the frequency read 111.10 and the user clicked above the left knob, the frequency would increase to 112.10. If the user instead clicked above the right knob, the frequency would increase to 111.20. More information on instrument navigation is found in Chapter 12.
5. Navigation Source Selection Switch - To the right of the NAV 1 radio is the navigation source selection switch. This selects between navigating using the frequency on the NAV 1 radio and that of the NAV 2 radio; tap the switch to change its position.
To the right of the navigation source selector is the NAV 2 radio. This is functionally identical to the NAV 1 radio.
The electronic flight instrument system (or EFIS) displays much of the same information as the six gauges in the propeller-based aircraft, with a few additions.
1. Airspeed Indiicator (ASI) - The scrolling tape on the far left is the airspeed indicator. Once again, this is the indicated airspeed, not necessarily the true airspeed (see the discussion above for information on why this is so). Directly below the scrolling tape is the craft's speed relative to the speed of sound, just like in the HUD view.
2. Attitude Indicator - In the center of the first display (labeled 2 in the screenshot above) is the attitude indicator. This shows the aircraft's pitch and roll attitude in space relative to the horizon. As in the HUD view, there are lines above and below the representation of the aircraft that mark degrees of pitch. Additionally, the two purple lines (one horizontal and one vertical) serve as part of the horizontal situation indicator (HSI)—specifically, the lines represent the course deviation indicator (CDI) Note that this is tuned using the OBS (omnidirectional bearing selector) found in the lower half of the panel. More information on using the HSI for navigating is found in Chapter 12.
3. Altimeter - The scrolling tape on the right is the altimeter. This displays the airplane’s altitude in feet above mean sea level.
4. Horizontal Situation Indicator (HSI) - In the bottom of the first EFIS panel is a modified view of the horizontal situation indicator (HSI). This is a combination of a directional gyro (DG) and the course deviation indicator (CDI). The DG is a gyroscopically driven compass, which makes it much more stable than the older "whisky" compasses (so named because of the whisky alcohol used to stabilize the compass inside the housing). It is the DG portion of the HSI that is marked 4 in the image on the previous page. Once again, more information on flying on instruments can be found in Chapter 12.
5. Autopilot Controls- At the top of the panel are the autopilot controls. Use of the autopilot is described in Chapter 12.
6. Moving Map - The right display panel of the EFIS is the moving map. The local airport’s identifier is shown in blue—in the case of the above screenshot, this is the default field for X-Plane 9, LOWI. The magenta triangles are the localizers which set up the approach for that runway at that airport. Most unusually, the LOWI airport has two localizers—one pointing away from the field and one pointing toward it. More information on using the localizers can be found in Chapter
The Settings Menu
Selecting the fifth menu option from the left (marked in the image below) will open the Settings menu.
The Settings menu has nine tabs across the top, each of which shows a different set of options when selected. Tap one of the tabs to change the settings there, and tap the Fly button in the upper left to go back to the simulation.
The options available on the Map screen are simple: Place the craft in a random location or on whole new random flight by pressing the respective buttons. The buttons in the lower half of the screen place the aircraft either on the runway for the indicated airport (the Takeoff buttons) or on a final approach to that runway (the Final buttons). The map can be dragged using a single finger or zoomed in or out using two fingers, just like when using the external aircraft view. Additionally, placing two fingers on the screen and moving them in a circular motion (“swizzling” them) will rotate the map.
Tapping the Center button will center the map on your aircraft.
Zoom into the map near a navigational aid (NAVAID) or airport to view detailed information about it such as its ILS or VOR frequency.
The Map tab is also where you can reset a flight after a crash. Upon crashing, open the settings menu, which will come to the Map tab by default. Tap one of the location buttons (either for an airport or for a random flight) to “fix” your virtual aircraft and start a new flight.
The Region menu allows the user to select which region to fly from. Tap a region to load it. The specific regions available in each app are discussed in that app’s chapter.
The Plane tab lets the user pick one of the four to nine different airplanes included in each app. Tap an aircraft to load it (it will be placed on the default runway for the current region). The specific craft available in each app are discussed in their respective chapters.
The Weight menu is interesting. Here, the user can drag the center of gravity forward to give the craft greater stability, or aft to make it more maneuverable. The weight of the aircraft can be adjusted the same way, using the slider—just tap it and drag. Lighter airplanes will of course perform better than heavier ones.
The Time tab of the Settings window allows the user to set one of four times of day, and thus four corresponding levels of daylight.
The Sky tab is used to set one of five cloud conditions. You can also change the cloud base height and the visibility. To move a slider, simply tap and drag it.
The Wxr tab, seen above, allows the user to set the weather. It has four sliders, each of which is moved just like in the rest of the app. The top two sliders set the wind speed and turbulence, which together define how rough a flight will be. Below these sliders is the storm cell “level,” which sets how sever the thunderstorms in the area will be. The two sliders at the bottom of the screen control the region’s thermals—that is, the columns of rising air in the area. The slider on the bottom left sets the rate in feet per minute at which the thermals move, and the slider on the bottom right sets the percentage of the flight region’s area which is covered by thermals. With the thermals set to 1000 fpm with 50% coverage, it will be very common to encounter very strong rising columns of air.
Finally, the round button on the right side is used to set wind direction. To move this, tap near the edge of the circle and drag your finger around the circle. Wherever your finger releases is where the wind will come from.
The Set menu allows the user to change the phone or iPod’s “control calibration.” Just hold the device at the desired angle and tap the Set current phone pitch and roll as center button to make the current attitude of the phone or iPod the point for which input is zero. This lets users fly with the device in their lap when sitting or standing, or held vertical when lying down—kind of convenient!
In the X-Plane 9 app, there is a button labeled Show instructions in flight if in Cessna 172. This enables on-screen, step-by-step instructions for taking off, climbing, cruising, approaching the runway, and landing in the Cessna 172.
Additionally, at the bottom of this screen is the sound slider, set by default at 50%.
The Multi tab is used to set up multiplayer flights. When it is selected, X-Plane will search for other devices running the simulator. Both users need to tap the button labeled with the other user's device in order to play with that person. For example, if William and Mary want to fly together, William will need to go to the Multi tab and tap the Mary's iPod button, and Mary will need to go to the Multi tab and tap the William's iPhone button. Note that the button is selected when it turns a very light gray color. When both users have selected the other, click Done and X-Plane will set both users at the default runway.
Also, note that both users must be on the same wireless network in order to play together. This is configured in the iPhone/iPod's Wi-Fi setup (found in the device's Settings, as shown in the image below).
In multiplayer mode, hitting the other aircraft will result in damage (sometimes fatal) just like hitting the ground in the simulator. If this occurs, simply open up the Settings menu and take off from an airport again. Note that both users must select the same airport if they are to fly together; otherwise, X-Plane assumes that the users want to start in different places and meet up somewhere.
Finally, when in multiplayer mode, a pointer will appear (in the shape of a little airplane) near the compass indicating the other user's location. Follow this pointer to join up with the other player in the event that you lose each other.
Updating the X-Plane Apps
The easiest way to update the mobile X-Plane applications is to go to the App Store (found on the device's "home page") and tap Updates down at the bottom of the screen. There, simply select Update All (as marked in the image below). The device will prompt for the username and password that were used to purchase the applications, then it will automatically download the updates.