Chapter 4: Taking Off, Flying, and Landing
From X-Plane Wiki
Let's go over the flight operations of a few representative aircraft. If you aren't sure where to find the controls mentioned here (flaps, throttle, brakes, etc.), see Chapter 2: Getting Acquainted with the iPad/iPhone 4G Simulator.
Contents |
...in the Cessna 172
The Cessna 172SP is the most straightforward of the aircraft included with X-Plane for iPad/X-Plane HDEF 4G—it's what many student pilots learn to fly in.
To begin takeoff in the 172, touch the FLAP slider and drag it about a third of the way down. This will partially engage the flaps in order to generate more lift, thus getting the airplane off the ground more quickly.
Next, tap the BRAKES button to toggle the brakes off. It will go from being lit red (brakes on) to being dim (brakes off).
Then, drag the THROT slider to the top of the screen. This will set the throttle at full.
When the airspeed reaches about 65 knots, pull the nose off the ground and begin climbing. Raise the flaps slider back up to the top of the screen in order to reduce the craft's drag.
To climb most efficiently, raise the nose to the point that the aircraft's speed is 76 knots. At full throttle, this is when the craft's nose is pitched up at about 10 degrees.
After climbing awhile (say, about 2,000 feet), you may want to level off and begin cruising. At this point, move the throttle slider down to about three quarters of its maximum and gently move the nose down to a pitch of zero
Eventually, you will want to turn back to the runway. To do this, tilt the iPad/iPhone to the left or right and tilt it back slightly (thereby pulling the nose "into" the turn).
Keep turning until the runway is in sight. Ideally, the aircraft will be oriented in line with the runway while it is still far off. This is referred to as the approach to the runway. On the approach, keep the craft's airspeed a little above 90 knots.
As the craft gets closer to the runway, gradually decrease its speed, either by lowering the throttle or by adding flaps. This gradual slowdown should put the plane at a little under 70 knots when it touches down on the runway, with its power at zero and flaps at full. Follow a shallow glide path in to the runway—that is, point the nose down between 3 and 5 degrees. Right before the craft reaches the ground, raise the nose up to about 7 degrees for a gentle touchdown.
With the aircraft on the ground, tap the BRAKES button to toggle the brakes on.
Now that the flight is complete, open the Settings menu (as described in Chapter 2) and select a new flight.
...in the Cirrus Vision SJ50
We will go through the takeoff and flight in the Cirrus Vision SJ50. Flight operations in this jet will be nearly identical to those in other high-end general aviation craft—simply substitute in that aircraft's takeoff speed (found in the chart in Chapter 3) for the 80 knots specified here for the Cirrus.
Tap the BRAKES button on the lower left of the screen to turn the brakes off. Drag the flaps (controlled with the scroll bar on the right side of the screen in the HUD view) about 1/3 of the way down to get ready to take off. This will partially lower the flaps in order to give the craft more lift, getting it into the air more quickly. Do not put the flaps all the way down because they would add too much drag. Full flaps are only used when landing.
With the flaps dialed in, drag the throttle (the scroll bar on the left) all the way to the top. This will give the aircraft full power.
Tilt the iPad/iPhone left and right to steer down the runway, holding the device at about a 45 degree pitch (for a neutral elevator). When the craft reaches about 80 knots (indicated by the scrolling tape on the left side of the screen), tilt the device back toward you to raise the nose and get the craft off the ground.
After the craft has risen a few feet, let the nose drop back down a bit to (nearly) level off, but don't settle back to the runway. Let the plane accelerate for a few moments like this (until it reaches, say, 100 knots), then resume climbing. Leveling off in this way will provide a “cushion” of speed for the aircraft so that when it begins to climb in earnest, it will be less likely to slow down toward the stalling speed.
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 the craft's 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. In the Cirrus Vision, a speed of around 130 knots is desirable when climbing.
Tilt the device left and right to steer, and hold the nose about 10 degrees up to climb away from the runway. Hit the GEAR button to raise the landing gear, and, once the craft is safely in the air, drag the FLAP slider back up to the top to fully retract the flaps. Continue to hold the nose up about 10 degrees as the plane climbs out. In the climb, both the gear and flaps should be up and power should remain at full. When flying, always keep the plane’s speed above about 80 knots as an absolute minimum to avoid stalling. It may be necessary to either add power or lower the nose to maintain this speed.
...in the F-22 Raptor
Let’s go through the basics of takeoff and flight in the F-22 Raptor, an aircraft which will serve as a decent representation of the other fighters (like the F-14 and F-15) as well.
First, tap the BRAKES button on the lower left of the screen to turn the brakes off. Because of the excessive amount of power available in the Raptor, flaps are not required to take off. Drag the throttle all the way to the top of its range of motion. This will give the aircraft full power. Tilt the iPad/iPhone left and right to steer down the runway (being careful not to hit the plane in front of you), holding the device at about a 45 degree pitch (for a neutral elevator). When the craft reaches about 120 knots (indicated by the scrolling tape on the left side of its HUD), tilt the device back toward you to raise the nose, and away you go.
Keep in mind that this airplane is excessively powerful and that is also uses thrust vectoring—that is, it points its exhaust up and down on each engine independently to aid in roll and pitch control. The engines produce more then 35,000 pounds of thrust each when in full afterburner. Compare that with the F-16 which puts out about 24,000 pounds of thrust total. Because the Raptor’s engines vector the thrust up and down with the flight controls, yanking the stick back rapidly while on the runway will cause the engine's thrust to slam the tail into the ground and the nose will point excessively high upward. Users in the past have commented that this is not possible, that the Raptor can not possibly take off in such a short distance. Of course, the plane has not really taken off yet—it's just sliding down the runway dragging its tail on the asphalt. Look at the altimeter to determine when the aircraft is actually in the air and climbing.
Once off the ground, tilt the device left and right to steer. Hit the GEAR button to raise the landing gear and make sure the flaps slider is at the top of its range of motion. Hold the nose up about 30 degrees or so as the plane climbs out. In the climb, both the gear and flaps should be up. Given the amazing power this airplane produces, the throttle can be brought back a bit in order to get out of afterburner mode.
Once again, remember that the craft's indicated airspeed may be different from its true airspeed due to the design of the instrument itself. This becomes especially important at high altitudes, where there is little to no air hitting against the airspeed measuring device on the body of the craft.
...in the Boeing 747
Flying X-Plane's airliners is quite different from flying, say, the Cirrus Vision. The airliners are much, much heavier than the other planes, and thus require a great deal more lift to get off the ground. For pilots who are used to flying light planes, these behemoths will feel very sluggish.
Let's walk through flight in the Boeing 747, a good representative of the airliners included with X-Plane for iPad/X-Plane HDEF 4G.
To begin, tap the BRAKES button to toggle the brakes off. Drag the flaps about one third of the way down. Pulling in the flaps like this will provide some extra lift to get the aircraft off the ground more quickly. Next, drag the throttle slider all the way to the top of its range of motion, giving the craft full throttle.
When the aircraft reaches about 160 knots, gently tilt the device back in order to pull the craft's nose off the ground.
Keep it climbing at a shallow pitch (say, about 5 degrees) for a few seconds in order to get away from the ground, then gently raise the plane's nose up to about 15 degrees. Toggle the gear up, then bring the flaps back to the top of their range of motion. Setting the flaps back to neutral like this will minimize the drag on the craft as it climbs.
Continue climbing until the desired altitude is reached. At that point, level the nose off and bring the throttle down to about three quarters of its maximum.
Use the trim control (currently available only in the HUD view) to hold the desired pitch of the nose. For instance, to hold the nose up, drag the trim control down a bit. To hold the nose down, drag the control up a bit. This is ergonomically equivalent to using a real trim wheel, which the pilot rolls up to push the nose down, or down to pull the nose up.
In order to maintain control of the 747, be sure to always keep its speed above 140 knots as an absolute minimum. Holding a more comfortable speed of 170 or 180 knots is desirable.
Now let's discuss landing the 747. Approaches to the runway can be easily practiced by selecting the Final button from the Map screen (found in the Settings menu—see Chapter 2). This will set the aircraft lined up with the indicated airport while still a few miles away.
When the desired airport is in sight and the aircraft is lined up with it, it's time to begin the approach in earnest. The key to the approach is to gradually slow the craft down while also gradually descending to the level of the airport.
Ideally, the airplane will have slowed down to just above its stall speed at the point that it touches down. In the 747, this means its speed should be gradually decreasing on the approach so that the instant before it touches down, it is traveling at about 150 knots. In order to slow to this speed, it will be necessary to slowly back the throttle down and pull in full flaps (by dragging the flaps control to the bottom of its range of motion). The speedbrake may also be required—drag it down to decrease the aircraft's speed.
In the descent, pitch the nose downward between 3 and 5 degrees. This will provide a shallow, controlled descent. In the seconds before the aircraft touches down, raise the nose up to about 7 degrees. This will cause the back wheels to touch down first, yielding a very smooth landing.
Once flying has been mastered using the manual controls, try flying with the autopilot or landing using an ILS, both of which are described in Chapter 6: Advanced Features of X-Plane for iPad/X-Plane HDEF 4G.
...in a Glider
When starting out in one of the two unpowered gliders (the ASK 21 or the Cirrus), the simulator puts the craft on the runway behind the Cessna towplane. The towplane's engine is running, and it's ready to go. Releasing the glider's brakes (by tapping the BRAKE button) commands the towplane to take off, dragging the user's craft with it.
When flying the Schempp-Hirth Cirrus, the gear should be raised once the craft is off the ground. This enables the user to squeeze every last bit of performance from the glider.
The towplane, once in flight, will take the glider as high as the user likes, and while being carried up, the glider will have to hold formation behind it as it pulls the glider to altitude. Tapping the HOOK button located in the bottom right corner of the screen will release the line between the aircraft, allowing the glider to soar freely.
Notice, of course, that until the HOOK button has been pressed, the tow rope connecting the two aircraft is attached to the towplane's tail and the glider's nose. X-Plane models the real physics of this situation, so if the glider pulls left, right, up, or down, it will drag the towplane'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—the towplane (which will likely be crashing) will be dragging the glider with it! The dynamics of the resulting crash are... interesting.
According to the FAA handbook for gliders, a glider pilot should keep the glider in one of two positions when being towed to altitude. It should either be in a “low tow” position, wherein the glider is just below the wake from the towplane, or it should be in a “high tow” position, just above the wake from the towplane. Hold this position carefully to keep from dragging the towplane around!
Taking off in the SZD-45 (the powered glider) is like taking off in any other plane—run the throttle all the way up, pull in a little bit of flaps, then pull back at around 50 knots. Then, once the glider reaches altitude (with the flaps up, of course), drag the throttle slider back down to idle and soar like any other glider!
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, the user 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.
Unique to the gliders is an instrument called the total energy 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—the glider has been blown to the wrong side of the mountain, and a crash will follow soon if the user does not find a way out of that area!
Now, 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't have enough speed to reach the landing strip, the glider has no way of generating thrust. For instance, in the following image, the speedbrakes are fully engaged, and the glider will reach the runway just a hair above its stalling speed.
...in a Helicopter
The following is a description of how helicopters are flown in the real world, along with the application of this in X-Plane. As you are about to see, flying a helicopter is very difficult and much more demanding than flying a fixed-wing airplane.
Though all manner of different helicopter layouts can be found in reality, we will discuss only the standard configuration here—a single overhead rotor with a tail rotor in the back, like the Robinson R22 Beta. Here's how it works: first, the main rotor provides the lift needed to support the aircraft, exactly in the same way that an airplane's wing supports its weight, or its propeller pulls it through the air.
Quite unlike an airplane propeller, though, a helicopter's rotor spins at the same RPM in all phases of flight. Whereas an airplane propeller speeds up in order to generate thrust, the amount of lift generated by a helicopter rotor is controlled by adjusting the pitch of the main rotor blades. This is done using the collective control.
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’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 at this point. Now, when the pilot is ready to go flying, he or she begins by pulling up on a handle in the cockpit called the collective. 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—"collectively."
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. Since it is a lot harder to turn the blades, they start to slow down—if this were allowed to happen, it would be catastrophic, since the craft can’t fly when its rotor isn’t turning! To compensate for this, the helicopter's feedback sensors will increase the throttle as much as necessary in order to maintain the desired 400 RPM in the rotor. In X-Plane, the effect of this throttle governor can be seen in the slider on the right side of the screen while in the HUD view, as highlighted in the following screenshot.
So, increasing the collective pitch of the main rotor will increase the lift generated by it, thus pulling the helicopter off the ground. However, because of the main rotor's inertia and its increasing drag as its pitch increases, the force required from the engine to spin the rotor also increases. When the throttle governor increases power to meet this need, the torque delivered from the main rotor blades to the fuselage of the helicopter will change. This torque (and the fact that it is continually changing) must be compensated for in order to keep the craft flying straight.
This compensation comes in the form of the tail rotor, controlled with the foot pedals in a real helicopter. The pilot must continually be making small changes with his or her feet (changing the pitch of the tail rotor blades just like the collective control does to the main rotor blades) in order to correct for the torque of the main rotor. This torque itself is continually changing depending on the amount of power delivered to the main rotor by the engine.
X-Plane will try to stabilize the tail rotor automatically. However, in most cases, it is a good idea to manually control it using the TR slider, found at the bottom of the screen (see the screenshot below). Remember, move this left to turn the helicopter left, and move it right to turn right. This will need to be moved back and forth as the collective pitch of the main rotor is changed (which changes the power delivered by the engine and the energy absorbed by the rotor).
Incidentally, the tail rotor is geared to the main rotor so that they always turn in unison. If the main rotor loses 10% RPM, the tail rotor loses 10% 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’s pitch that is being controlled with the anti-torque pedals (that is, the TR slider in X-Plane for iPad/X-Plane HDEF 4G).
Once the craft is in the air and the collective pitch of the main rotor is being adjusted (in X-Plane for iPad/X-Plane HDEF 4G, using the sliding control on the left side of the screen), the helicopter pilot in the real world will use the cyclic control (the joystick) to tilt the craft left, right, down, or up. In X-Plane, this is controlled by tilting the iPad/iPhone left, right, fore, and aft.
The cyclic control works like this: If the cyclic is moved to the right (corresponding to the device being tilted 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, continually going to a higher or lower pitch. If we use the example from before, this means that the rotor would change its pitch from one condition to the other, and back again, 400 times per minute (7 times per second), because the rotor is turning at 400 RPM. Pretty impressive, especially considering that the craft manages to stay together under these conditions! The fact that moving the stick sends the blade pitch through one cycle every rotation of the rotor blades is why we call the control stick the cyclic.
Let'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. Surprising, right? One might have assumed that if we wanted to turn right, we would increase lift on the left side of the helicopter, thereby lifting the left and causing the helicopter to roll right. This isn't how it works, though, due to the fact that gyroscopic forces are applied 90 degrees along the direction of rotation of the gyroscope, which is why the lift must be changed in front of the helicopter to enact a change on the left of the machine.
Here’s an amazing experiment that you can try on your own to see how this works. Sit on a free spinning (low friction) bar stool with a bicycle wheel in your hands. Have a friend spin the tire as quickly as possible while you hold the wheel stationary with one hand on each side of the axle. Now, after your friend backs away a bit slowly rotate the axle about the lateral (fore and aft) and roll axes and you will be surprised at how you can control your spinning motion on the stool by making controlled movements with the bicycle wheel. Cool!
Here’s something else that is surprising—the helicopter’s rotor doesn’t directly pull the aircraft to change its flight path. To turn right, the helicopter must increase the lift on the front of the rotor, which causes the left side of the rotor to come up (tilt to the right). But the rotor doesn’t force the helicopter to roll to the right; only the angle of the rotor itself is changed. The resulting change in the direction of lift is what actually changes the flight path of the helicopter. Once the rotor (and thus the helicopter's thrust vector) is tilted to the right, it will drag the craft off to the right. In fact, the thrust vector from the main rotor can be broken down into two components, vertical lift (which supports the weight of the helicopter) and horizontal lift (which causes the helicopter to accelerate to the right).
We said that the helicopter's rotor doesn't directly pull the craft to change its flight path. This is because the rotor on many helicopters is totally free-teetering; it has a completely "loose and floppy" connection to the craft. It can not conduct any force (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.
To summarize, this is the sequence for getting a helicopter to fly (in the real world, as well as in X-Plane):
- 1. While on the ground, the collective handle is flat on the ground. This means the rotor pitch is flat, with minimum drag and zero lift. In X-Plane, a flat collective corresponds to the collective control (found on the left side of the screen) being at the top of its range of motion. The automatic throttle in the helicopter is obsessively watching the rotor’s RPM, adjusting the throttle as needed to hold exactly the design RPM (which varies from helicopter to helicopter). 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 the user decides to take off, s/he does so by raising the collective up by pulling it up from the floor of the helicopter. In X-Plane, this is done by easing the sliding bar collective control down toward the bottom of the screen. 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 its operational speed, 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 the required RPM.
- 3. More collective is pulled in until the blades are creating enough lift to raise the aircraft from the ground. The auto-throttle continues adding power to keep the rotor turning at its operational RPM no matter how much the collective is raised or lowered.
- 4. The tail rotor is actively controlled to keep the helicopter from spinning due to torque and gyroscopic effects. Any change made by the pilot or nature will require input in the other two controls. Thus, the pilot must continually be making small adjustments to the cyclic (the control stick—controlled with the device's tilt), collective (the lever to adjust main rotor pitch—controlled with the COLL slider) and anti-torque pedals (to adjust tail rotor pitch—controlled with the TR slider) to account for changes based on moving any of these controls.
Use the above information to hover perfectly. Once that is mastered, 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.
Notes
Remember that in this application the throttle is automatically controlled for the helicopter. It is shown only as a visual indicator of how hard the engine is working. Be careful not to command more lift from the main rotor (with the collective control) than the engine is capable of providing or the rotor RPM will decay and the craft's flight will quickly deteriorate.
Note that the collective is dragged down to increase its pitch. This is ergonomically similar to the collective in real helicopters, where pilots pull the collective handle towards them to increase the collective. Thus, in X-Plane, the collective control is dragged towards the user (that is, down on the screen) to increase it.
Review
To review, helicopter flight in X-Plane follows these steps:
- 1. The collective slider, found on the left side of the screen, is dragged down gently in order to increase the pitch of the main rotor. This increases the lift generated by the rotor. As this is done, the throttle, shown on the left side of the screen, will automatically increase. This is caused by the throttle governor automatically increasing the engine power to maintain the desired rotor RPM as the rotor load is increased (caused by increasing the rotor’s pitch). This is how the real helicopters work, and thus how they are simulated in X-Plane.
- 2. The TR slider (controlling the tail rotor) is dragged left to turn the helicopter left (or to counter rightward torque). It is dragged right to turn the helicopter right (or to counter leftward torque).
- 3. The device is tilted left, right, forward, and back to move the craft in each respective direction. This corresponds to input from the stick (the cyclic control) in a real helicopter. Remember that what is actually happening with the cyclic is that the rotor is being made to roll and pitch around the helicopter, thereby changing the thrust vector. This thrust is what causes the helicopter to accelerate either forward, rightward, rearward or leftward.
...in the Space Shuttle
Flying the Space Shuttle is quite different from flying the other aircraft in X-Plane. In the real world, almost all of the Shuttle’s flight is controlled by its computers—it is “hands off” for the astronauts. This is the case for the Launch mission in X-Plane for iPad/X-Plane HDEF 4G. However, in X-Plane, unlike in almost every mission in the real world, you can pilot the Shuttle down by hand for the full re-entry. This makes for a great challenge, and it’s a lot of fun!
Beginning a Space Shuttle Mission Segment
To begin a mission segment in the Space Shuttle, select it in the Plane tab of the Settings menu (per Chapter 2). With the Orbiter selected, the Map tab of the settings menu will be replaced by the screen seen below:
Tap the desired mission segment, then tap the Go! Button to begin the simulation.
Launch
The first mission segment is the launch phase. Here, the user can simply watch as the launch is run. Displayed throughout the launch are the Shuttle’s speed, altitude, time into flight, and time until orbit. The simulator will accurately recreate how long it takes for the Shuttle to reach orbit (eight and a half minutes) and the maneuvers that it goes through on the way there. This kind of visualization isn’t normally possible—after all, the Shuttle is out of range of the cameras within about two minutes of launch, so we never see the whole flight to orbit. In Space Shuttle, though, the entire path to orbit is faithfully reproduced, so users can see what really happens, as fast as it really happens.
It is fascinating to watch the indicated air speed (found in the HUD view—see Chapter 2 on how to select this) slowly fall to zero knots as the Shuttle climbs into space and the air pressure drops to nothing. Also, watch the take off from the HUD view and note how the shuttle only climbs vertically for the first 40 seconds or so, after which it begins to tip over on its back. The shuttle then climbs inverted for the next 300 seconds or so (nearly five minutes), until the spacecraft rolls upright at about 330 seconds after liftoff.
The simulator also puts into perspective the duration of the main engine burn after the solid rocket boosters burn out and are jettisoned. This shows visually why the external fuel tank (the orange-colored center cylinder) is so gigantic in comparison to the Shuttle.
ISS Dock
In this segment of the mission, the user will dock the Space Shuttle with the International Space Station orbiting the earth.
To do this, the user must monitor quite a few controls at once. First, the Shuttle's pitch and roll (controlled using the device's tilt) as well as its yaw (controlled using the YAW slider at the bottom of the screen) must be used to properly align the shuttle with the docking hatch in three dimensions.
While keeping the pitch, roll, and yaw on target, the user must carefully use the throttle control (found on the left side of the screen) to bring the Shuttle in. This slider goes from full forward (at the top of its range of motion) to full backward (at the bottom of its range of motion), and releasing it will reset it back to zero thrust (in the center of the screen). Be sure to have the craft's velocity under 1 meter per second when it meets up with the ISS.
Finally, while keeping the pitch, roll, yaw, and throttle where they need to be, use the translational thrusters (the control in the box on the right side of the screen) to align the body of the Shuttle with the space station. The orange circle in the center of the screen and the moving orange dot show where the translational thrusters need to push the craft. Simply drag the thruster control in the direction of the circle relative to the dot to properly align the Shuttle. For instance, if the circle is above the dot, drag the translational thruster control up, and if the circle is to the right of the dot, drag the thruster control right, etc. When the Shuttle is right on target, the orange dot will be inside the orange circle.
Keep all of these controls where they need to be and docking will be a breeze.
Final Approach
The final approach is the easiest of the mission segments. The Shuttle will be placed on an eight mile final approach to Edwards, and the user will have to glide down to the runway as in any glider (this one just happens to have a pretty poor glide ratio). The speedbrake (the slider in the upper right of the HUD view, labeled SBRK) will likely be required to get the craft’s descent profile just right. The Shuttle should be slowed to about 250 knots as it approaches the runway, and it should be descending on about a 20 degree glide path until the VASI lights beside the runway turn from white to red. At that point, raise the nose (this is called the “pre-flare”) and follow that shallow 3 degree glide path in for the final bit of the approach for touchdown. Don’t forget to lower the brakes at the last second!
If the approach is flown correctly, the pilot will
follow a 20 degree angle down,
adjust the speedbrakes to slow to 250 knots,
raise the nose as the lights beside the runway start to turn red,
lower the landing gear,
follow a path in that keeps two of the lights beside the runway white and two of them red (if more are red, the craft is too low, and if more are white, it’s too high),
touch down in a nose-high attitude,
lower the nose,
hit the brakes, and
be stopped well before the end of the runway.
That is, at least, how the pros do it.
Full Approach
The full approach provides a greater challenge than the final. It starts the aircraft off at 83,000 feet and moving at Mach 2.5, 40 miles downrange of landing. This approach is a bit trickier: The pilot will need to raise or lower the nose to hold the desired angle of attack (thus keeping a proper drag profile) while slaloming back and forth to get rid of surplus energy. The Shuttle will be slaloming back and forth through the stratosphere at Mach 2, trying to dissipate just the right amount of energy to arrive over Edwards at the right speed and altitude to land.
Onscreen instruction is given during the flight in the cockpit view to help guide the user through it. This is the orange text marked in the following screenshot.
As the approach progresses, the little yellow shuttle in the far right EFIS screen will glide down the green line to Edwards. If the craft gets below that line, it has too little energy (meaning it is it is either too low or too slow). Pull the nose up and level the wings in order to conserve energy in the thick air of low altitude. If the craft gets above the green line, it has too much speed or altitude. Bring out the speedbrakes (found in the center right of the HUD screen) and slalom left and right (like a skier) to lose the extra energy. This is what the real Space Shuttle does to dissipate energy. If the user can manage this, he or she is flying very much like the real Orbiter pilots would.
Re-Entry
Once the full approach has been mastered, try the "Final Re-Entry" option from the Missions screen. This will start the aircraft 600 miles downrange at 200,000 feet, moving at Mach 10. This is a true challenge.
Worth noting is the fact that the Shuttle starts out 600 miles away, 40 miles straight up, and moving at Mach 10. By the end of the re-entry, it will be sitting on a runway that is only a couple hundred feet wide and a few thousand feet long. Even more remarkable, this is done without a bit of power from the craft’s engines—it gets there on nothing but inertia, drag, and careful flight. The cockpit displays (coupled with the orange help text at the top of the panel) do indeed make it possible!
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