The primary cockpit displays include a left- and right-side cathode-ray tube display, referred to as the DDIs, and the head-up display (HUD), shown in Figure 4. A photo of the instrument panel and left console are shown in Figure 5c. The DDIs and HUD Figure 5a are generally used to display primary flight condition information such as airspeed, altitude, altitude rate, attitude, heading, RFCS status, etc. Other flight conditions displayed include angle of attack (AOA), Mach number, and load factor. The boxed RFCS (HUD middle right) indicates that the RFCS is armed and engaged. The HUD also provides primary flight condition information to the pilot without having to refer to the DDIs. Select flight controls information also can be presented on the HUD.
The twenty pushbuttons located on the periphery of each DDI are used to select a variety of displays for pilot interrogation of F-18 HARV systems, (see left DDI, fig. 4). These displays are pilot selectable and menu driven. The menu select button is located on the lower center of each DDI. Depressing the menu button provides an indication of the particular display function adjacent to the appropriate button (only the major functions are shown). As an example, for the flight control system, a status, caution, and/or failure message matrix can be annunciated by selecting the FCS button (lower right-hand button). The F-18 HARV airplane incorporates some displays designed specifically for the HARV mission, such as the boxed RFCS.
The F-18 HARV retains the basic F-18 cockpit controls with some exceptions, which will be noted. The pilot's center control stick is relatively typical of a modern fighter aircraft. The table above presents the pilot's stick and rudder pedal position limits, force gradients, and breakout forces. Feel springs provide stick and rudder gradients. The stick grip includes the switches for pitch and roll trim and nosewheel steering engagement. The F-18 HARV has no weapons delivery capability. The dual-function paddle switch, located just below the grip, is for nosewheel steering disengagement on the ground, and RFCS disengagement.
| F-18 HARV pilot's cockpit control characteristics. | |||
| Control | Position limit, * in. | Force gradient, lb/in. | Breakout force, lb |
| Pitch stick | |||
| Aft | 5.0 | 8.0 | 3 |
| Forward | 2.5 | 8.6 | 3 |
| Left and right lateral stick | 3.0 | 4.3 | 2 |
| Left and right rudder pedal | 1.0 | 100 | 7 |
Independent throttling of the left or right engine is possible through split throttle levers located on the left console figure 5b The pilot's friction control is provided for adjustment of throttle lever force. The three-position (extend, hold, and retract) speed brake thumb switch is located on the inboard side of the right-engine throttle lever.
To accommodate the RFCS, additional flight control system switches were added and some of the existing switches were functionally modified fig 5c. A RFCS mode control panel was added outboard of the left DDI. The panel contains a guarded RFCS arm/off switch and status light. When this switch is in the armed position, the RFCS is armed and the status light is illuminated. Momentary depression of the nosewheel steering engagement button, located on the control stick grip, engages the RFCS when the arm/off switch is in the arm position. The arm/off or control stick paddle switch can be used to disengage the RFCS.
Various aerodynamic research experiments were conducted on the F-18 HARV. Switches for control of these experiments were located on the research systems control panel located at the lower center of the instrument panel. These switches operated in conjunction with the gun trigger switch. The configuration of this panel and the function of the gun trigger switch varied with the particular experiment flown.
