F-104S Manual
AILERON AND RUDDER TRAVEL LIMITING SYSTEM
Aileron and rudder travel is limited automatically when the gear is UP, and unlimited when the gear is DOWN. With gear DOWN, aileron travel is approximately +-20° and with gear UP, aileron travel is approximately +-10°. An additional 5° of aileron travel may be obtained with gear UP by using aileron trim.
With gear DOWN, rudder travel is 20° (+-2°) to either side of neutral and with the gear UP, rudder travel is limited to 6° either side of neutral. An additional 4° of rudder travel is available with gear UP if rudder trim is used. Aileron and rudder limiting circuit is powered by the PP2 DC bus. If electrical failure occurs, rudder and aileron travel will not be limited.
Pulling the RUD/AIL LIMIT CONT circuit breaker, on the left console, will remove the rudder and aileron travel limiters (refer to Section VI "Flight Characteristics" for additional information on this system).
Aileron and rudder travel is automatically unlimited when gear is DOWN or when gear is UP and a flaps asymmetry condition exists as detected by the flaps asymmetry detection system. When the aileron and rudder travel is unlimited, a warning light on the main instrument panel illuminates.
WARNING
THE USE OF FULL UNLIMITED AILERON OR RUDDER TRAVEL IN MANEUVERS AT SPEEDS ABOVE 300 KIAS MAY RESULT IN STRUCTURAL DAMAGE AND POSSIBLE LOSS OF THE AIRCRAFT.
AILERON ROLL LIMITATIONS
In order to avoid inertial coupling and high structural loads approaching limit values, aileron rolls are subject to the following restrictions:
WING FLAPS RETRACTED
Entry Load Factor of 0.5 "G" and Greater
Full deflection rolls are limited to 360°. Below l "G” with pitch or yaw stability augmenters inoperative, full deflection 360° rolls are prohibited.
Entry Load Factor Less Than 0.5 "G”
Full deflection 360° rolls are prohibited. All rolls below 0.5 "G” load factor shall be executed with extreme caution.
NOTE
Application of some back stick pressure during roll helps to terminate the roll more rapidly and make a smoother transition to normal ilight.
AILERON ROLLS
Aileron roll characteristics within the prescribed limits are excellent. Because of inertial coupling tendencies peculiar to all supersonic configurations, certain restrictions on rolling maneuvers have been imposed to prevent loss of control and/or exceeding structural limits.
These inertial coupling tendencies result from the large pitch and yaw inertia of the supersonic configurations and the angular relationship of the longitudinal inertia axis of the aircraft with the axis of rotation. This angular relationship varies with flight conditions (speed, altitude and load factor). Depending on whether the inertia axis is nose-up or nose·down relative to the flight path or rolling axis, a sideslip is developed during a roll which produces inhibiting or augmenting roll rate. In extreme cases, if sufficient aileron control power is allowed, this divergent type roll rate due to sideslip may result in excessive rolling velocity, uncontrollable, rolls or damage and failure.
ln order tn remain within safe limits. the available aileron travel is reduced with gear up to prevent high roll rates. ln addition, the amount of continuous rotation is placarded in all configurations to prevent large amounts of sideslip from developing.
http://www.916-starfighter.de/F-104_...20Coupling.pdf