AST 473 Cessna Citation II Basic Avionics and

AST 473 Cessna Citation II Basic Avionics and Flight Instrumentation (UNs 210 – 626) Dr. Barnhart

Avionics & Flight Instrumentation • Important note: Avionics vary widely according to specific aircraft. Spend time learning your aircraft • FSI’s sim. Is the old steam gauge II (models a S/N 0210 – 0626)

Avionics • Sperry electromechanical – Dual audio control panels – Dual VHF Comm. Transceivers – Dual Navs. – Dual RMI’s, ADF, DME – Autoflight system (altitude pre-select, alt. alert, alt. reporting, and vert. nav. ) – Weather Radar

Avionics • Pilot’s Flight Instruments: – ADI (5 inch, Dual-cue flight director, 12 annunciators for flt. Director modes)- displays AOB, G/S, T&B, Loc, Radio alt) – HSI – RMI (w/ ADF) – Altimeter- driven by Air Data Computer (ADC)

Avionics • Co-Pilot’s instruments: – Basic 6 -pack layout w. HSI – RMI (with ADF) (altimeter is conventional barometric)

Avionics • Flight Guidance- SPZ-500 autopilot/FDcomplete flight control system: – Flight Director – Autopilot – Pilot’s ADI/HSI – Air Data Computer – Autopilot controller – Vert. Nav. System- alt. alerter, Touch Cnt’l Steering (TCS), rate gyro, autopilot servos

Avionics • Flt. Guidance System- operates via the pilot’s ADI/HSI – ADC provides P. A. input, alt. reporting, alt. pre -select, IAS hold and vert. speed mode – Can be flown manually or automatically – Meets CAT II requirements

Avionics • Mode Control Panel– Push on/off backlighted switches – Displays selected flight director mode- amber when armed or green when captured – FD OFF- puts command bars down out of view- doesn't affect autopilot

Avionics • Autopilot Control Panel- provides means of engaging autopilot and yaw damper (as well as manually controlling autopilot via turn knob and pitch wheel) – Two torque modes (high and low speed- baro. set to 14, 500 ft. in co-pilot’s static system) – Autopilot switch engages autopilot and Yaw Damper (aid to pax. Comfort)

Avionics • Autopilot ctn. – SOFT RIDE switch- maintains stability in rough air- minimizes autopilot gains. – TEST EACH FLT- activates a test of the current monitor for A/P • Pressing causes A/P to disengage- simulates failure of torque limiters- must disengage w/I 2 sec. • AUTOPILOT OFF illuminates and warning sounds • TRIM light illuminates UP/DOWN when sustained signal applied to elevator servo- trim out servo pressure prior to disengaging A/P if TRIM lt. illum.

Avionics • Touch Control Steering (TCS)- pilot’s cnt’l. wheel- allows manual mvm’t. of A/C during autopilot ops. w/o cancellation of any selected mode. - Interrupts A/P ops. releasing button re-engages autopilot • When using F/D & flying manually- TCS matches command bars to existing pitch attitude or V/S mode can be reset w/ TCS

Avionics • VNAV Computer/Controller- provides data inputs for alt. pre-select mode (ALTSEL), alt. alert, or vert. nav. Mode (VNAV). - data input w/ data sel. Switch and then setting w/ SET knob. • VNAV ops. Only when using NAV 1 w/ DME set to NAV 1 and locked on VORTAC • VNAV fcn. Only valid when going directly to or directly from a VOR/DME station

Avionics • C-14 Compass System- pilot’s HSI and flight director and co-pilots RMI driven by the slaved gyro system. Components: – DG – Flux Detector – 2 mode selector switches – Remote compensator – Slaving indicator on HSI – 2 LH GYRO SLAVE switches- on left panel

Avionics • Ctn. – 1 w/ AUTO and MAN – Other w/ LH/RH position Allow selection of auto (slaved) or manual (unslaved). In AUTO (for normal ops. )compasses align @ 3 – 5 deg. /sec. IN MAN. HSI on co-pilot’s RMI card can be moves L or R @ 30 deg. /min. by toggling the LH-RH sw. (slaving indicator on HSI goes away).

Avionics • Ctn. – Co-pilot’s compass system- identical to pilots but drives co-pilot’s HSI and pilot’s RMI card – If DC fail- place BATT sw. in EMER. Restores pwr. To co-pilot’s HSI

Avionics • Radio Altimeter- Optional- provides absolute altitude readout from 2, 500 AGL to gnd. In 10 ft. incr. (5 ft. below 200 AGL) – Aux. output can be used to drive a rising runway bar on pilot’s ADI – A DH window is included on ADI to set DH

Avionics • AOA system (optional)- Transmitter (conical sensor), flap position sensor, and indicator. – Indicator- computes AOA from transmitter and Flap sensor to provide readout. – Calibrated from 0 – 1. 0 At 0 no lift produced – Red arc- beginning of low speed buffet to stall – Yellow- approaching critical AOA – Indices at. 8 (low speed buffet), . 6 - [optimum app. speed- 1. 3 V(SO) and V(X), and max. endurance], and. 35 (max. range)

Avionics • Airspeed Indicators- uncorrected pitot/static input • Mach. Input (same gauge, -different needle)from Air Data Computer (ADC) • Built in ref. bug • Slots in dial @ 262 and 277 KIAS show red below 14, 000 ft. and from 14, 000 to 28, 000 ft. indicating V(MO) limits (@std. 9, 500 lbs ZFW) • Mach limit of. 705 abv. FL 280 - single red radial line

Avionics • 2 IVSI- show vert. velocity from 0 – 6, 000 ft. - springs and accelerometers used to reduce normal VSI lag.

Avionics • Static Ports– 2 per side- fwd. of cockpit windows – Dual pickups used to reduce sideslip effects – Co-pilot’s altimeter- barometric. • Due to low vibration in turbojets this instr. Has an elec. Motor w/ an eccentric shaft attached to a baro. Altimeter to ensure its accuracy- constantly vibrates it

Avionics • Air Data Computer- electrically drives pilot’s altimeter and provides input to FD/AP system plus any optional equipment installed which require it. • Static Discharge Wicks- dissipate Precip. Static (P static) which reduces electrostatic noise- installed on all trailing edges.

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