MISC Panel Operation

Roll Ratio Switch
AUTO Provides normal system functions
EMERG Removes hydraulic pressure from the hydromechanical roll control system which causes the roll ratio to drive to a midrange and lock. Mechanical Aileron-Rudder Interconnect (ARI) is also disabled.

The Roll Ratio control is part of the F-15s lateral control system.

Lateral stick motion positions the ailerons rudders and stabilators to
provide roll control. The ratio of aileron/differential stabilator deflection
to lateral stick motion (roll ratio) is adjusted automatically for different
airspeeds, longitudinal stick position and gear position. This provides
the same roll response for a given stick deflection regardless of airspeed.
Aileron and differential stabilator deflection are washed out to prevent
adverse yaw when longitudinal stick deflection is combined with lateral stick deflection. At subsonic speeds, the roll ratio is reduced. With the landing gear down, full aileron/differential stabilator is available at any
longitudinal stick position. If UTL A and PC2A hydraulic pressures are lost
or the roll ratio switch is in EMERG, the roll ratio system drives to mid-range and locks. A spin recovery aid provides full lateral control authority, regardless of longitudinal stick position, when the yaw rate exceeds 60 degrees per second. Full lateral authority will be discontinued when the yaw rate is less than 60 degrees per second.

The mechanical Aileron-Rudder Interconnect (ARI) adjusts the control system such that lateral stick motion results in varying rudder deflection dependent on longitudinal stick position. With the control stick aft of neutral, lateral stick motion causes rudder deflection in the same direction as stick motion.

With the control stick forward of neutral, lateral stick motion causes rudder deflection in the opposite direction of the stick motion. In addition, when the flaps are down, the amount of rudder deflection for lateral input is increased. The ARI is disengaged at supersonic speeds and on landing. If the anti-skid system detects a malfunction or the landing gear circuit breaker is OUT, the ARI may remain engaged at wheel spin up, adversely affecting crosswind landing characteristics.

Turning the anti-skid switch OFF or PULSER will insure ARI disengagement. If UTL A and PC2A hydraulic pressures are lost or Pitch or Roll Ratio switch is in EMERG, the ARI is inoperative. If the mechanical system is inoperative, the differential stabilators (through roll CAS) will provide lateral control for moderate manuvers including landing.

Landing and Taxi Lights
OFF Lights are off.
LDG LIGHT If the nose gear is down and locked through 73-107 or the landing gear handle is down (74-081 and up), the landing light is turned on.
TAXI If the nose gear is down and locked through 73-107 or the landing gear handle is down (74-081 and up), the taxi light is turned on.

The landing and taxi lights are on the nose gear strut. They are controlled by a toggle switch on the miscellaneous panel. The lights are off, regardless of switch position, on aircraft through 73-107 when the nose wheel is not down and locked, or on aircraft 74-081 and up, when the landing gear handle is in the up position.

Inlet Ramp Switch
AUTO The AIC automatically controls the air inlet system. This is the normal position.
EMERG Removes electrical power from the ramp and bypass door actuators,
causing them to move hydraulically to the emergency (ramps locked up and bypass door closed) position. If hydraulic pressure fails, airloads will force the ramps and bypass door to the emergency position.

An inlet ramp switch for each inlet is on the miscellaneous control panel.
The switch is lever locked, and has positions of AUTO and EMERG.

Anti-Skid System
NORM The anti-skid is on when the gear is down. However, illumination of the ANTI-SKID warning light activates the brake pulser system and ARI is disengaged with the gear down.
PULSER Turns off normal anti-skid protection, turns on the ANTI-SKID and MASTER CAUTION lights, and activates the brake pulser system. The ARI is disengaged with the gear handle down.
OFF Turns off the normal anti-skid and brake pulser systems. Disengages ARI with the gear handle down.

Operational information on this page taken from TO 1F-15A-1, Change 1 – 15 August 1984