# Key Bindings

The 727 autopilot is quite different from those used in modern aircraft. Its behavior often differs, so make sure you understand what you are binding and how.

### INCREASE/DECREASE VERTICAL SPEED

| Autopilot Mode                                 | Operation                                                               |
| ---------------------------------------------- | ----------------------------------------------------------------------- |
| <p>VERT SPEED</p><p>(ALT HOLD not engaged)</p> | Changes pitch to achieve +/- 100 ft/min                                 |
| <p>VERT SPEED</p><p>(ALT HOLD engaged)</p>     | No effect                                                               |
| PITCH HOLD                                     | Changes pitch to achieve approximately + 100 ft/min                     |
| IAS HOLD                                       | Switches to VERT SPEED mode and changes pitch to achieve +/- 100 ft/min |

### INCREASE/DECREASE HEADING BUG

Decreasing rotates the HDG bug to the left, increasing rotates the HDG bug to the right

### HEADING HOLD (ON/OFF/TOGGLE)

Operates the HDG SEL BUTTON

### AUTOPILOT ALTITUDE HOLD (ON/OFF/TOGGLE)

Operates the HDG SEL BUTTON. Be aware that this is not an altitude hold but just an arming mode to capture the preselected altitude. It needs to be re-engaged whenever you change the preselected altitude.