|WLV: WING-LEVELER: This will simply hold the wings level
while you figure out what to do next. (To be precise, WLV is actually
attitude hold. When you engage it the plane will hold its current roll
|HDG: HEADING HOLD. This will simply follow the heading bug on the HSI or Direction Gyro.|
|V/S: This will hold a constant VERTICAL SPEED by pitching the aircraft nose up or down.|
|HOLD: This will hold the current ALTITUDE by pitching the nose up or down.|
|SPD: This will hold the pre-selected AIRSPEED by pitching
the nose up or down (leaving throttle alone). You control the plane's
climb or descent rate indirectly with the throttle.
|PTCH: Pitch-Sync: Use this to cause the plane to hold its nose at a constant pitch attitude. Commonly used in King-Airs to just hold the nose somewhere until the pilot decides what to do next.|
|ATHR: This will hold the pre-selected AIRSPEED by adding or taking away engine thrust.|
|FLCH: Flight Level Change: Same as SPD, only if ATHR is on,
automatically selects either full or idle power, depending on whether
you intend to climb or descend.
|LOC: Localizer. This will fly a VOR radial or ILS localizer, or to a GPS destination.|
|G/S: Glideslope: This will fly the glideslope portion of the ILS.|
|APP: Approach: This is simply
the combination of the LOC and G/S buttons. It will fly the localizer
and glideslope components of the ILS.
|TERR: Terrain Following: This
will fly the aircraft at a low altitude, barely clearing the ground.
|VNAV: Vertical Navigation: This will fly the altitude commanded by the FMS if you have an FMS in your airplane.|
|BC: Every ILS on the planet has a LITTLE-KNOWN SECOND LOCALIZER THAT GOES IN THE OPPOSITE DIRECTION AS THE INBOUND LOCALIZER. THIS IS USED FOR THE MISSED APPROACH, ALLOWING YOU TO CONTINUE FLYING ALONG THE EXTENDED CENTERLINE OF THE RUNWAY, EVEN AFTER PASSING OVER AND BEYOND THE RUNWAY. To save money, some airports will NOT bother to install a new ILS at the airport to land on the same runway going the other direction, but instead let you fly this second localizer BACKWARDS to come into the runway from the opposite direction of the regular ILS! This is called a BACK COURSE ILS. Using the SAME ILS in BOTH directions has it's advantage (it's cheaper) but a drawback: The needle deflection on your instruments is BACKWARDS when going the WRONG WAY ON THE ILS! Hit the BC (back coourse) autopilot button if you are doing this. It causes the autopilot to realize that the needle deflection is BACKWARDS, and still fly the approach. (Note: HSI's do NOT reverse the visible needle deflection in the back-course because you turn the housing that the deflection needle is mounted on around 180 degrees to fly the opposite direction... thus reversing the reversal!) (NOTE: The glideslope is NOT available on the back-course, so you have to use the localizer part of the procedure only.)|
|CWS: Control Wheel Steering. Temporarily disconnects the autopilot and allows you to fly the plane under manual control. There is no panel button for this function; to use it you must assign a joystick button.|
|The flight director switch, if
your aircraft has one, controls the operation of the autopilot. If the
flight director switch is OFF, your autopilot is OFF and does not fly
the plane. If you have engaged an autopilot mode and it doesn't appear
to be working, check the flight director switch! If the plane does not
have a flight director switch, engaging any autopilot mode
automatically turns it on.
|When the flight director switch
is in the ON position, the autopilot is still not controlling the
plane. Instead, it is controlling an attitude cue in your artificial
horizon. You fly the plane so that the attitude cue is level and
centered in the artificial horizon to follow the autopilot course.
|When the flight director switch
is in the AUTO position, the autopilot controls the plane. This is the
switch position you must set to have the autopilot actually fly the
|WING-LEVELER and PITCH SYNC:
Just hit them and they hold the current roll and pitch attitudes.
|Terrain Following: Just hit the
button to engage, and be prepared for a wild ride! A plane with fast
pitch response is highly recommended!
|AUTO-THROTTLE: Engage AUTO-THROTTLE and the speed setting is set to your current speed. The autopilot will adjust the throttle to maintain the set speed. Change the setting to adjust your speed.|
Just hit it and the autopilot will fly the heading you've entered in the heading selector (shown) or the heading bug on the HSI. You can change heading while in the HDG mode and the autopilot will follow. The outer dial on the Heavy Metal heading selector allows you to set the maximum roll angle the plane will use in turns.
Just hit it and the autopilot will simply hold the CURRENT altitude. The altitude selector is not strictly necessary; if present it will indicate the altitude being held.
First select your target altitude. Then engage VERTICAL SPEED and the autopilot will climb or descend to the selected target altitude. When it arrives at the target altitude the autopilot switches over to ALTITUDE HOLD mode. When you engage VS, your vertical speed is initially set to your current vertical speed. Once engaged, use the vertical speed selector to dial in your desired vertical speed.
ATC will often tell you to expect a new altitude in 10 minutes, so you can dial the expected altitude into the autopilot in advance, even though you aren't allowed to actually climb or descend yet. Thus, FIRST enter the desired altitude. Then, whenever you like, hit the VS button to go to that altitude. Then enter a NEW altitude... the plane will not go there until you press the VS button again!
Keep an eye on your airspeed and adjust throttle and/or vertical speed as necessary (or use ATHR)! VS will try to maintain your set vertical speed and will stall the plane trying.
||FLIGHT-LEVEL-CHANGE or SPD:
You must be established with ALTITUDE HOLD, holding a constant altitude and constant speed. Dial in the new altitude and hit the FLCH or SPD button. If you have AUTOTHROTTLE engaged, FLCH causes the autopilot to automatically set engine power to maximum or idle, depending on whether your target altitude is higher or lower than your current altitude. SPD does not alter your throttle setting. Once engaged, you can adjust your climb or descent rate by changing your throttle setting.
When do you use VS and when do you use FLCH? FLCH is an effective mode for climb-out in heavies. It allows you to set the engines for climb power, and then let the plane climb to cruise altitude at whatever rate the engine power will allow. Remember that the engines become less powerful at higher altitudes, so your climb rate must be less as you approach cruise level. If you try to climb out using VS mode with a set vertical speed and ATHR, you'll periodically have to reduce your climb rate to avoid overstressing the engines, or, in the extreme case, running out of power, losing airspeed, and stalling the plane.
VS is the better choice for descent, giving you a predictable descent rate, and with ATHR, predictable airspeed, getting you to target altitude at the right time and place.
|CWS: Control Wheel Steering. Press and hold the joystick button that you've assigned to engage CWS. This will temporarily disconnect the autopilot and allow you to fly the plane under manual control. When you release the button you disengage CWS and revert to the previous autopilot mode, but with the settings changed to match the plane's current situation. For example, if you were in ALT mode, you revert to ALT mode, but at your new altitude. If you were in VS mode, you revert to VS with your new vertical speed.|
|LOC, G/S, and APP:
These modes follow your selected navaid signal. LOC flies a VOR radial, an ILS runway localizer, or a GPS leg. GS flies an ILS glideslope. You have potentially three nav sources: the NAV1 receiver, the NAC 2 receiver, or the GPS. But how do the autopilot know which of those 3 signals to use? The answer is the switch labelled "NAV-1 NAV-2 GPS". This switch causes the HSI and the autopilot to use either Nav-1, Nav-2, or the Flight Management Computer (which gets its signal from the GPS).
|If you set this switch to Nav-1, then the the HSI will show deflections from the Nav-1 radio, and the autopilot will fly VOR or ILS signals from the Nav-1 radio if you hit the LOC or G/S buttons.|
|If you set this switch to Nav-2, then the the HSI will show deflections from the Nav-2 radio, and the autopilot will fly VOR or ILS signals from the Nav-2 radio if you hit the LOC or G/S buttons.|
|If you set this switch to GPS, then the the HSI will show deflections from the GPS, and the autopilot will fly to the GPS destination if you hit the LOC button. Remember that if you enter destinations into the FMS, they will automatically feed into the GPS, so the autopilot will follow them if you select LOC|
|Hit the altitude HOLD button to hold your current altitude (if you haven't already used VS or FLCH to fly to and hold an approach altitude).|
|Enter a HEADING in the HEADING window to hold until you
intercept the ILS. Check your map to make sure the heading will cross
the localizer centerline an adequate distance away from the airport.
|Hit the HEADING HOLD button to hold it.|
|Hit the LOC button. It will ARM (orange)|
|Hit the G/S button. It will ARM (orange)|
|Now, as soon as you intercept the
the LOC will go from orange to yellow, abandoning the HEADING mode and flying the localizer.
|Now, as soon as you intercept the
CENTER of the glideslope:
the G/S will go from orange to yellow, abandoning the ALTITUDE HOLD mode and flying the glideslope. The autopilot will then track you right down to the runway, and even flare at the end, cutting power if autothrottle is engaged.
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