✈ CESSNA CITATION SOVEREIGN · PTM REV 5.0 · CE-680

SOVEREIGN POCKET GUIDE

Version 2.0 · Created by Leonardo Maia · FOR TRAINING PURPOSES ONLY
STUDY PROGRESS 0 / 19 chapters studied
01
AIRCRAFT GENERAL
Certification · Structure · Systems Overview · Access Doors
Part 25
FAR / JAR Certification
2
Minimum crew (PIC + SIC)
FL470
Maximum operating altitude
Cat I/II
ILS approach category
🏗️ Aircraft Structure
  • Pressurized, low-wing monoplane — transport category
  • Two PW306C turbofans pylon-mounted on rear fuselage
  • Tricycle trailing-link landing gear — dual wheels on all three legs
  • Moveable horizontal stabilizer for pitch trim
  • Vortex generators on wing upper surface for stall characteristics
  • Approved: day/night, VFR/IFR, known icing, Cat I and optional Cat II
  • PIC must hold a Sovereign type rating; both pilots need multi-engine land rating
📦 Compartments & Access
  • Nose compartment (unpressurized): MAU 1 & 2, avionics, pneumatic emergency bottles (gear blowdown + brakes), NWS accumulator, standby battery, avionics cooling fan, pitot-static drains
  • Cabin/cockpit: forward bulkhead to aft pressure bulkhead
  • Tail cone baggage compartment: unpressurized — fire/smoke detection system
  • APU compartment: below vertical stabilizer — titanium firebox
  • MAU 3 & 4: above baggage compartment (tail cone)
  • Batteries (2): rear fuselage in stainless steel containers
  • Engine fire bottles (2): tail cone — cross-feed capable
⚠️ Engine Danger Areas

Inlet suction hazard zones and exhaust blast zones extend significantly around each engine during operation. Personnel and FOD must be kept clear. Tire chines on the nose gear deflect standing water away from engine inlets.

💡 Doors monitored by CAS: NOSE DOOR OPEN L/R — each door has 2 mechanical latches + 1 safety latch; individual microswitch on each latch. CABIN DOOR OPEN, TAILCONE DOOR OPEN, BAGGAGE DOOR OPEN also monitored.
02
ELECTRICAL POWER SYSTEMS
DC Split-Bus · Generators · Batteries · Bus Tie · EPU · APU Generator
28 VDC
Nominal system voltage
300A
Continuous per engine generator
44 Ah
Main battery capacity (NiCad 25V)
35±0.5V
Generator overvoltage protection
⚡ Split-Bus Architecture

The Sovereign uses a DC split-bus configuration. Under normal operations the left and right bus systems are completely isolated. Left side: L engine generator + L battery. Right side: R engine generator + R battery. The Bus Tie Relay connects both systems at the Emergency Buses.

L/R Engine Generator (300A)
→
L/R Gen Bus
→
Avn + Interior Bus
→
Elec Bus
→
Emergency Bus
→
Critical systems
EICAS Bus: powered from the R Emergency Bus via a DC/DC converter — ensures stable power for EICAS during engine starts. If main DC power is lost, EICAS button must be selected OFF (indications become unreliable).
🔋 Power Sources — Complete List
  • Engine generators (2): 28 VDC / 300A constant. Up to 450A during starts (transient, max 2 min post-start completion). Air-cooled, mounted on AGB. Controlled by GCU.
  • APU generator: 28.5 VDC / 275A normal. Up to 450A during engine starts. Cannot be online simultaneously with L engine generator — priority logic prefers engine generator.
  • EPU (External Power Unit): 28 VDC / max 1,500A. EXT PWR button: AVAIL (connected, voltage OK) → ON.
  • Main batteries (2): 25V / 44 Ah NiCad — tail cone stainless containers. Manual quick-disconnect on each case. All systems: 20 min. Emergency buses only: 60 min.
  • Standby battery: nose compartment — dedicated to standby instruments.
  • 4 cabin emergency lighting packs: independent, for evacuation.
  • PMA (×2): permanent magnet alternators on AGB — power FADECs above 25% N2.
  • AC alternators (×2): on each engine — power windshield heat system only.
🔄 Bus Tie Relay Logic
  • ON GROUND — Auto CLOSE when: START button pressed (L or R engine or APU) · EXT PWR selected ON · Single generator comes online
  • ON GROUND — Auto OPEN when: Engine start complete (57–59% N2) · APU start complete (50% RPM) · Both bus systems have primary power · Major overcurrent
  • IN FLIGHT: Bus tie does NOT auto-open or close — must be activated MANUALLY by crew (generator loss or in-flight start)
  • Exception: Once manually closed in flight, will only auto-open on major overcurrent. Cannot be re-closed until total aircraft electrical power-down.
  • CAS BUS TIE CLOSED (cyan) when relay is closed on ground.
🎛️ Electrical Panel — Controls
  • L/R GEN (3-position): ON · OFF · RESET — RESET attempts fault clear via GCU
  • L/R BATT: ON closes relay, connects battery bus to emergency bus. OFF = CAS BATTERY OFF L/R
  • L/R AVN: ON/OFF — controls avionics relay. EICAS independent of AVN buttons.
  • ELEC NORM/EMER: NORM = generators power buses. EMER = manually opens electrical relay → CAS DC EMER BUS L/R
  • INTERIOR button: NORM = powers cabin J-box (all cabin equip except emergency lights). AUTO SHED on generator loss. OFF = deactivates cabin equipment (EMER LTS and ENTRY lights unaffected).
  • EICAS button: ON supplies emergency bus power to EICAS bus (DU2). Select OFF during electrical emergency.
  • BUS TIE button (guarded): Status indicator OPEN/CLOSED. No effect on ground — ground tie is automatic only.
  • DC/DC Converter: Maintains 24 VDC min for FADECs and EICAS during voltage sag on starts. Located next to aft J-box.
BATTERY LIMITS — MEMORIZE
24VMinimum battery voltage for engine / APU start
20 minBattery endurance — all systems powered
60 minBattery endurance — emergency buses only
IMPORTANT: Batteries must be ON (or generators operating) prior to and during ALL APU operations — required to power the fire protection system.
03
LIGHTING
Interior · Emergency · Exterior · Tail Cone
🔆 Cockpit Lighting Controls
  • PANEL rheostat: all glass-gauge panel and control panel lighting intensity
  • EL PANEL rheostat: electroluminescent panel lighting (alphanumeric characters). Powered via small AC inverter (EL INVERTER CB).
  • FLOOD rheostat: overhead floodlights
  • AUX rheostat: LED indirect lighting under glareshield — powered by emergency DC (AUX PNL LIGHT CB)
  • DAY/NIGHT button: DAY = all buttons at max intensity, bypasses rheostats. NIGHT = buttons dimmed, rheostats active, ice detection lights activate.
  • Map lights: powered from R CB panel
🚨 Emergency Lighting
  • Independent battery packs (4) in cabin sidewalls — independent of main DC
  • Illuminates for nighttime/low-visibility evacuation
  • ENTRY lights: powered by battery bus — 5 cabin overhead lights + 6 stair step lights + 1 external first-step light + 2 threshold lights. AUTO timer: 10 min if main DC is lost with lights ON.
  • Cabin emergency lights unaffected by INTERIOR button OFF selection
✈️ Exterior Lighting
  • Position/navigation: wing tips and tail
  • Anti-collision (strobe): upper and lower fuselage
  • Landing/recognition: nose area
  • Taxi lights: on nose gear lower barrel (turn with NWS)
  • Wing inspection lights: 2 per side, forward of wing root — illuminate leading edge for night ice detection
  • Windshield ice detection lights (2 LEDs): on glareshield — aimed at unprotected inboard windshield area. Active in NIGHT mode.
  • Tail cone lighting: interior lights for maintenance area and baggage compartment
04
MASTER WARNING SYSTEM
MAU Architecture · CAS Message Logic · EICAS · Aural Priority
🧠 MAU Architecture — 4 Units
  • MAU 1 & 4: Monitor Warning System (MWS) — process, prioritize, and display CAS messages. First to power = controlling display MAU.
  • MAU 2 & 3: Activate MASTER WARNING/CAUTION lights and aural warnings as commanded by MAUs 1 & 4.
  • MAUs 1 & 2 in nose avionics compartment. MAUs 3 & 4 above baggage compartment.
  • Each MAU has independent power supply + independent cooling fans.
  • MWS comparison: MWS 1 (MAU1) vs MWS 2 (MAU4) continuously cross-check CAS computations.
  • MW1/MW2 amber CAS: miscompare between MWSs. Crew can switch via MCDU (Menu/Display Setup) to determine which stack is correct — only available when miscompare occurs.
  • ASCB (Avionics Standard Communications Bus): bidirectional network linking all MAUs, displays, and avionics units.
EICAS MISCOMPARE: Wraparound test compares values sent to EICAS vs. values displayed. If they differ → amber EICAS MISCOMPARE flashes on both PFDs, right of HSI. Cross-check with standby engine instruments (direct from FADEC — more accurate).
📊 CAS Message Colors — Characteristics
🔴 RED — WARNING
  • Immediate action required
  • MASTER WARNING buttons FLASH
  • Double chime (or voice message)
  • Appears top of stack — cannot be scrolled out of view
  • Flashing white-on-red (inverse video) until MASTER WARNING pressed
  • Continues flashing even if condition clears — MUST be reset
🟡 AMBER — CAUTION
  • Immediate awareness + crew action
  • MASTER CAUTION buttons illuminate steady
  • Single aural chime
  • Flashing black-on-amber (inverse video)
  • Auto-extinguishes if condition clears (before reset)
  • Newest message appears at top of amber block
🔵 CYAN — ADVISORY
  • System status information; some require action
  • No MASTER WARNING/CAUTION
  • Flashing black-on-cyan for 5 seconds → self-acknowledges
  • Phone/doorbell sounds for calls/SELCAL only
  • No aural warning
⚪ WHITE — INVALID DATA
  • Amber dashes replace numeric values on sensor failure
  • Does NOT trigger warnings, cautions, or CAS messages
  • Does NOT trigger any inhibits
  • EICAS colors: Green=normal, Amber=caution, Red=exceedance
🔊 Aural Warning Priority (Highest → Lowest)
  • 1. EGPWS "Windshear"
  • 2. EGPWS "Pull up"
  • 3. Red CAS messages (voice or double chime)
  • 4. Abnormal AP disconnect
  • 5. Remaining EGPWS aurals
  • 6. TCAS Resolution Advisory
  • 7. TCAS Traffic Alert
  • 8. Amber CAS messages (single chime)
  • 9. Trim clacker
  • 10. Normal AP disconnect
  • 11. Altitude alert
  • 12. Decision height
  • 13. Vertical track alert
  • 14. ATS message aural
  • 15. Cyan messages (none)
  • 16. Repeating aurals
Voice messages available for (red): "Cabin Altitude" · "Left/Right Engine Failed" · "APU Fire" · "Baggage Fire" · "Battery Overtemperature" · "Generators Off" · "No Takeoff" · "Left and Right Engine Fire" · "Emergency Descent" — all other red messages use double chimes.
05
FUEL SYSTEM
Integral Wing Tanks · Boost Pumps · Ejectors · Crossfeed · SPR
11,223 lbs
Max fuel capacity (full SPR or overwing)
540 lbs
FUEL LEVEL LOW trigger (per tank)
500 lbs
EICAS fuel qty digits turn amber (per tank)
1,000 lbs
EICAS total fuel digits turn amber
⛽ System Architecture
Wing Tank (wet wing)
→
Hopper Tank (inboard)
→
Electric Boost Pump
+
Primary Ejector Pump (motive flow)
→
Engine HFCU → 24 nozzles

Each tank feeds its respective engine. APU feeds from the right wing tank. Crossfeed is available to either engine or APU. Both tanks are separated by a rib at the wing centerline — can be fueled individually or together via SPR.

🔧 Key Components
  • Engine Feed Hopper: integral inboard section of each wing. Houses boost pump + primary ejector.
  • Boost Pump (×1 per side): electric (DC), 25A CB in aft J-box. Supplies engine-driven fuel pump. Activates automatically during: engine start sequence · crossfeed · low fuel pressure. R boost pump also activates during APU operations.
  • Primary Ejector Pump: powered by motive flow from the engine-driven pump. No moving parts, no electricity required. Continuous fuel supply to engine-driven pump.
  • 3 Scavenge Ejector Pumps: forward, mid, aft per wing. Motive flow powered. Collect fuel from all wing areas into hopper — no electricity. Operate even without boost pump.
  • Crossfeed Valve: DC-powered motorized ball valve. If main DC fails → valve fails IN CURRENT POSITION.
  • Firewall Shutoff Valves: close when ENG FIRE button pressed. CAS: FUEL FW SHUTOFF L/R (white, valve fully closed); FUEL FW S/O TRANSIT (amber, valve in transit).
  • Fuel Quantity: 7 capacitance probes per wing + dual-channel FQSC. Fault = amber dashes on EICAS (invalid data, no CAS).
💡 Fuel System Logic
  • Boost pump AUTO logic: Activates automatically for engine start, crossfeed, and low fuel pressure (with BOOST buttons in NORM). Does NOT auto-activate in CUTOFF.
  • During engine start: FADEC activates boost pump → CAS FUEL BOOST ON L/R displayed. Pump deactivates at 57% N2.
  • Crossfeed flow logic: fuel flows from the heavier tank. CAS FUEL CROSSFEED = white (normal crossfeed). AMBER = fuel flowing from the lighter tank (reversed).
  • Motive flow valve fail: CAS FUEL MOTIVE VLV FAIL L/R — crossfeed from opposite tank may not occur; affected tank continues to feed.
  • Surge tank: near wingtip — collects overflow, vented via NACA flush scoop. Standpipe prevents siphoning.
  • SPR system: pressure refueling from single point. High-level float valve auto-shutoff. Precheck levers must be tested prior to fueling completion.
  • Waste fuel ejector: at engine shutdown, collects residual fuel from manifold. Reintroduced on next operation via ejector pump.
⚠️ Key CAS Messages — Fuel
FUEL LEVEL LOW L/R
Tank qty below 540±60 lbs. EICAS individual tank digits amber <500 lbs; total fuel amber <1,000 lbs. Debounce: 90 sec.
FUEL PRESSURE LOW L/R
Low fuel pressure to engine. Boost pump auto-activates → CAS FUEL BOOST ON L/R. Clears when pressure restored.
FUEL FILTER BYPASS L/R
Impending fuel filter bypass due to contamination. Inspect filter before next flight.
FUEL CROSSFEED
White = normal crossfeed (heavier tank). Amber = reversed flow (lighter tank).
FUEL BOOST ON L/R
Boost pump operating (normal start sequence or crew selected).
FUEL FW SHUTOFF L/R
Fuel firewall shutoff valve fully closed (post ENG FIRE action).
06
AUXILIARY POWER UNIT
Honeywell RE100(CS) · ECU · Bleed Air · Generator · Fire Protection
⚙️ APU Capabilities
  • Electrical: 28.5 VDC / 275A normal. Up to 450A assisting batteries during engine starts. Powers entire aircraft electrical system.
  • Bleed air: available for pressurization, air conditioning, and service air. NOT available for anti-icing systems (wing, engine).
  • APU bleed air: cooler than engine bleed — no precooler required (below 475°F/246°C).
  • Location: tail cone below vertical stabilizer — titanium firebox enclosure.
  • APU bleed vs engine bleed: APU supplies all bleed on ground and in flight up to ~FL200; above FL200, engine bleed pressure exceeds APU and takes over.
  • APU generator priority: cannot be online simultaneously with L engine generator. L engine gen has priority → APU auto-comes online if L gen fails (with APU GEN button ON).
🔄 Bleed-Air Control Valve (BCV)
  • Closed during APU start sequence.
  • Opens automatically or manually after READY TO LOAD illuminates.
  • MAX COOL operation: if RPM drops or EGT exceeds limit, PCB logic closes BCV to intermediate position. Temp selectors MUST be in AUTO — manual control risks EGT exceedance and automatic APU shutdown.
  • Service air does NOT pass through BCV — available anytime APU is running.
  • APU fuel: from R wing tank via electric motor valve. Opens when MASTER ON, closes on MASTER OFF, EMERGENCY SHUTOFF, or ECU command. If R engine motive flow available → no need for boost pump.
📊 APU Panel Annunciators
AnnunciatorMeaning
READY TO LOAD (cyan)APU at operating speed (≥95% RPM + 4 sec). Electrical and bleed air available for selection. A start cycle is counted when this illuminates.
APU RELAY ENGAGED (cyan)Starter-generator receiving start power. Extinguishes at starter cutoff (~50% RPM). Re-illuminates when APU relay closes again.
BLEED VALVE OPEN (cyan)APU BCV is open — normal when BLEED AIR button is ON.
APU SYS FAIL (amber)System malfunction — APU will not start, or has automatically shut down (failed self-test or protective shutdown).
🔥 APU Fire Protection
APU ON (amber CAS): APU running above FL300 — monitor EGT and consider shutdown.
07
POWERPLANT
PW306C · FADEC · Oil · Fuel · Ignition · Start Sequence · Thrust Reversers
5,770 lbs
Max thrust — S/L to 30°C
110%
N1 or N2 → overspeed shutoff valve
2 channels
FADEC — A and B, per engine
20 PSI
Oil pressure low CAS trigger
🔩 Engine Architecture — Twin-Spool Turbofan
N1 SPOOL (inner shaft)
=
Fan (Ti blades)
+
3-Stage LP Turbine
N2 SPOOL (outer shaft)
=
4 Axial + 1 Centrifugal Compressor stages
+
2-Stage HP Turbine
→
Tower Shaft → AGB
🛢️ Engine Oil System
  • Functions: lubricates, cools, and cleans bearings #1, #2, #3, #4 and N2 tower shaft bushing. Also lubricates AGB gears and starter-generator gear shaft.
  • Oil level check: via sight glass on filler tube. CAS OIL LEVEL LOW = only on ground with engines stopped, level too low for start.
  • Oil pump: on AGB — 1 pressure pump + 2 scavenge pumps.
  • Oil filter: 10-micron cartridge. Check valve allows replacement without draining tank.
  • Filter bypass valve: opens if filter contaminated. CAS OIL FILTER BYPASS. Inhibited at oil temp < –38°C.
  • Chip detector: on AGB — detects metal particles → CAS ENGINE CHIP DETECT L/R.
  • FOHE (Fuel/Oil Heat Exchanger): fuel cools engine oil AND oil warms fuel (prevents ice crystals in fuel lines).
  • Oil pressure transducer: analog indication on EICAS. Differential pressure switch: CAS OIL PRESSURE LOW L/R if pressure drops below 20 PSI. Standby OIL PRESS annunciator operates from emergency bus (survives electrical emergency).
🔥 Ignition System
  • 2 exciter boxes + 2 spark igniters per engine — combustion chamber. Engine can start with only 1 exciter + 1 igniter.
  • Power source: Emergency buses via two 3-position ignition switches.
  • 3-position ignition switch:
    — ON: continuous ignition (both exciter boxes powered at all times)
    — OFF: removes all power from exciter boxes
    — NORM: FADEC controls ignition operation (normal position)
  • FADEC ignition logic: applies ignition at 5.2% N2 during start; removes ignition at 40% N2. Reapplies as required in flight (turbulence, precip).
  • Green IGN indicator on EICAS: power received by at least one of the two exciter boxes.
  • CAS ENGINE CONTROL FAULT: displayed if ignition switch is NOT in NORM position.
⚡ FADEC — Full Authority Digital Electronic Control
  • Architecture: Two-channel EEC (A and B) + EDU per engine. Both channels in constant communication — only one controls at a time.
  • Channel alternation: channels alternate after each engine shutdown. After shutdown → FADEC automatically selects opposite channel for next start.
  • Power: Start Bus (28 VDC) until 25% N2 → PMA (self-sustaining). If PMA fault: reverts to start bus power.
  • N1 target calculation: non-controlling channel computes N1 target bug. If non-controlling channel fails → controlling channel computes bug → N1 target digits appear AMBER.
  • FADEC inputs: throttle position · ambient conditions (RAT) · WOW logic · anti-ice status · engine parameters (N1, N2, ITT)
  • Fault management: FADEC monitors inputs, hardware, and external driver circuits continuously. Fault in active channel → shifts to other channel automatically. Common/multiple faults → backup control loops, alternative input sources. Always selects most capable channel.
  • FADEC Channel Select buttons: display active channel (A or B). Can manually switch to non-controlling channel with engines running.
  • FADEC RESET buttons: attempt reset of a faulted FADEC channel.
  • EDU: stores pilot-recorded events, fault codes, engine exceedances, uncommanded shutdowns. Downloaded via remote maintenance port. Data transferred EEC → EDU after shutdown — keep batteries ON for 30 seconds post-shutdown.
  • Pilot Event Marker: button near pilot's PASS OXY knob — records 5-minute engine parameter trace in EDU (4 min prior + 1 min after activation).
⛽ Engine Fuel System
From wing tank
→
Firewall Shutoff Valve
→
Emergency Shutoff Valve
→
LP Boost Pump → FOHE → Fuel Filter
→
HP Boost Pump
→
HFCU → 24 fuel nozzles
🎚️ Throttle Positions — 4 Selectable
CUTOFF Engine shutdown position. Trigger under handle releases latch to enter/exit — prevents inadvertent shutdowns or starts.
IDLE Ground idle (WOW valid) or flight idle (airborne). FADEC regulates N2.
CRU Infinitely variable from cruise stop (high RPM) to IDLE. Pilot commands N1 directly.
MCT ✦ Detent — Maximum Continuous Thrust. FADEC determines N1 target for MCT power setting.
T/O ✦ Detent — Takeoff power. FADEC determines N1 target for maximum T/O thrust. N1 target indicator displays T/O, MCT, CRU values at top of N1 tape.
✦ Detented positions — FADEC automatically delivers the rated power setting
🚀 Start Sequence — Ground
EventWhat HappensKey Note
START pressedStarter engages, button light illuminates, boost pump auto-ONCAS FUEL BOOST ON L/R
3% N2FADEC checks VGV trackingVariable guide vane check
5.2% N2Ignition and fuel flow enabled — engine "lights off"Green IGN on EICAS
9% N2Advance throttle from CUTOFF toward idleCrew action
300°C ITTStart valve energizes fuel manifoldCombustion progressing
25% N2PMA takes over FADEC power from start busFADEC self-sustaining
40% N2Ignition deactivated — IGN extinguishes on EICASSelf-sustaining combustion
44% N2Starter disengages — START button light extinguishesStart relay opens
46% N2FADEC switches to non-controlling channel (redundancy test)Ground only
50% N2FADEC returns to controlling channel; start valve de-energizes—
54% N2Motive flow activatedEjector pump active
57% N2Boost pump OFF; Ground Idle establishedCAS ENGINE SHUTDOWN clears
100°C ITT over trendFADEC-initiated abort (ground only)Auto-abort trigger
⛔ Automatic Abort — Ground Only (VIT)
FADEC AUTO-ABORT TRIGGERS
VVGV tracking fault detected (at 3% N2)
IInsufficient ITT rise — less than 15°C in 15 seconds after fuel introduction
TTemperature 100°C deviation above the start trend line
Manual abort: pilot can override FADEC at any time by moving throttle to CUTOFF.
In-flight starts: auto-abort logic is NOT active. FADEC redundancy channel switchover test is NOT performed. Batteries are the only power source for the starter.
🔄 FADEC Governing Logic (Engine Running)
  • Ground Idle: lower N2 RPM to reduce acceleration during taxi. Active: throttle IDLE + WOW valid. After landing: FADEC commands ground idle 8 seconds after WOW. CAS GROUND IDLE L/R if airborne with ground idle active.
  • Flight Idle: higher N2 ensuring rapid response for go-around. Active: airborne + throttle IDLE. With anti-ice ON: FADEC adjusts fuel flow to maintain flight idle N1/N2.
  • Above idle: FADEC establishes and regulates N1 for T/O, MCT, CRU detents. At IDLE: FADEC regulates N2.
  • RPM Overspeed: FADEC limits N1/N2 by fuel regulation before red line. Overspeed solenoid valve shuts off fuel at ≥110% N1 or N2.
  • ITT overtemperature: FADEC reduces fuel flow to control temperature during start and operation.
  • Auto relight: if actual N2 drops below commanded N2 → FADEC activates igniter exciter boxes and attempts relight → CAS ENGINE SHUTDOWN until engine recovers.
  • Engine SYNC: SYNC NORM = left/right FADECs synchronize N1. Available inflight: gear UP, throttles above IDLE and below T/O detent. Capture range: 4% N1. Maintained within ±0.1% N1.
🔁 Thrust Reversers — Clamshell Type
  • Electrically controlled, hydraulically actuated clamshell-type reversers on aft engine nacelle
  • Aerodynamic forces keep reversers stowed at high-speed flight with throttles above idle — resist inadvertent deployment
  • Requires all three squat switches indicating ground — cannot deploy in flight (normal operation)
  • Controlled by piggyback levers on throttle handles
  • Isolation valve: solenoid-type — must open to allow hydraulic pressure to reach control valve. ARM indication = isolation valve open, hydraulic pressure present at control valve.
  • Control valve: double solenoid — directs hydraulic fluid to deploy or stow sides of actuators.
  • EICAS indications: ARM (isolation valve open) → UNLOCK (mechanical locks released) → DPLY (fully deployed). On ground: ARM/UNLOCK white, DPLY green. In flight: ARM/UNLOCK inverse-video amber + CAS; DPLY inverse-video red.
  • Reverse thrust: can only be increased once DPLY is displayed — system logic prevents premature increase.
  • Emergency Stow buttons (2 red): flash any time reverser inadvertently unlocks or deploys in flight. Pressing: opens isolation valve + commands control valve to STOW. Lights go steady once pressed.
  • T/R in-flight deploy: FADEC reduces affected engine to flight idle automatically.
  • T/R UNLOCK CAS (3–4 locks open): rudder bias moves to minimum position — rudder pedal force for single-engine ops increases significantly.
🔢 Powerplant — Key Numbers to Memorize
ValueWhat It Is
3%VGV tracking check (start)
5.2%Ignition + fuel flow enabled
9%Advance throttle (pilot)
25%PMA takes over FADEC power
40%Ignition off
44%Starter disengages
57%Ground idle established
ValueWhat It Is
20 PSIOil pressure low trigger
110% N1/N2Overspeed solenoid cuts fuel
300°C ITTStart valve energizes manifold
100°C ΔTAuto-abort (ITT above trend)
15 secNo ITT rise → auto-abort
30 secKeep batteries ON post-shutdown
8 secFADEC → ground idle post-WOW
⚠️ Key CAS Messages — Powerplant
ENGINE FIRE L/R
Fire loop detected high temperature in engine nacelle. Two loops per engine (outer + internal). ENG FIRE button on glareshield flashes. Pressing button: closes fuel + hydraulic F/W shutoff valves, deactivates generator, disables T/R, arms both fire bottles.
ENGINE FAILED L/R
N2 <~6% + not starting + throttle not in CUTOFF. Engine has failed when it should be running.
OIL PRESSURE LOW L/R
Oil pressure below 20 PSI. Standby OIL PRESS annunciator also illuminates (powered by emergency bus — persists during electrical emergency).
ENGINE CHIP DETECT L/R
Metal particles detected by electronic magnetic chip detector on AGB. Debounce: 5 sec.
ENGINE CONTROL FAULT L/R
FADEC detected internal fault or sensor miscompare — reduced redundancy. Also triggers if ignition switch not in NORM. Debounce: 1 sec.
ENGINE VIBRATION L/R
Excessive engine vibration detected any time engine is running. Debounce: 20 sec.
OIL FILTER BYPASS L/R
Oil filter contaminated — bypass active. Inhibited if oil temp <–38°C. Debounce: 2 sec.
GROUND IDLE L/R
FADEC in ground mode while aircraft is airborne. Inhibited on ground and TOPI/ESDI. Debounce: standard.
T/R ARMED L/R
Thrust reverser isolation valve open in flight. Inhibited on ground and TOPI/BFI.
T/R UNLOCK L/R
2+ of 4 mechanical locks sensed open in flight. 3–4 locks open: rudder bias moves to minimum position, increased pedal force required.
ENGINE DISPATCH LIMIT L/R
FADEC condition requiring logbook entry + maintenance within 125 hours. Inhibited in flight. Press EVENT MARKER to record additional data. Debounce: standard.
ENGINE SHUTDOWN L/R
Engine shut down via throttle CUTOFF, or below-idle recovery in progress. Clears after successful start sequence.
OIL LEVEL LOW L/R
Oil quantity too low for start. Ground only, engines not running. If oil level sensor fails: message also displayed amber.
08
FIRE PROTECTION
Engine · APU · Baggage · Interior — Detection and Suppression
🔥 Engine Fire Protection
  • 2 fire detection loops per engine: one around engine outer case + one internally. High temperature triggers cockpit indications.
  • 2 Halon fire bottles in tail cone. Each bottle can discharge to either engine (cross-connected).
  • ENG FIRE buttons (red, glareshield): illuminate when loop detects high temp → triggers MASTER WARNING flash + CAS ENGINE FIRE L/R + aural.
  • Bleed-air leak: throttle to IDLE → bleed temp drops → loop cools → ENG FIRE extinguishes within 15 seconds. If remains lit: full engine shutdown required.
  • Pressing ENG FIRE button: ① Fuel firewall shutoff valve CLOSES ② Fuel shuts off in HFCU ③ Hydraulic firewall shutoff CLOSES ④ Engine generator DEACTIVATED ⑤ Thrust reverser DISABLED ⑥ Both fire bottles ARMED
  • BOTTLE ARMED buttons (white): illuminate after ENG FIRE pressed. Press to discharge agent to the selected engine. Second bottle available if fire persists.
💨 Baggage Fire Protection
  • 2 smoke detectors in baggage compartment ceiling (forward + aft). Can detect smoke from any location within 1 minute.
  • On smoke detection: baggage heat shutoff valve automatically closes — stops bleed air flow into compartment.
  • BAGGAGE FIRE button (guarded, red): continuously armed with electrical power. Pressing: discharges Bag/APU bottle (tail cone) + low-rate squib of dedicated nose bottle simultaneously.
  • SEC BAG BOTTLE button (guarded): activates high-discharge rate squib of nose bottle — used during descent/landing phase. If not pressed: light flashes below FL250.
  • Nose bottle capacity: sufficient for max cruise 180 minutes (FL330–FL390) before descent must be initiated.
  • CAS FIRE BOTTLE LOW BAG-APU: tail cone bottle discharged → closes baggage heat, shuts down APU, inhibits APU start.
🧯 Fire Bottle Inventory — 5 Total
BottleLocationProtectsActivated By
Engine No.1 (Halon)Tail coneEither engineBOTTLE 1 ARMED button
Engine No.2 (Halon)Tail coneEither engineBOTTLE 2 ARMED button
Bag/APU (shared)Tail coneBaggage OR APUBAGGAGE FIRE or APU FIRE button (or auto in 8 sec)
Baggage (dedicated)Nose compartmentBaggage onlyBAGGAGE FIRE (low-rate) + SEC BAG BOTTLE (high-rate)
Portable (×2)Cockpit (R seat) + Fwd cabinInteriorManual by crew
APU fire auto-discharge: if APU FIRE button NOT pressed within 8 seconds of illumination → shared Bag/APU bottle discharges automatically into APU compartment.
09
PNEUMATICS
Bleed Air Sources · HP/LP Logic · Bleed-Air Leak Detection · Service Air
💨 Three Bleed-Air Sources
  • LP (Low-Pressure) compressor bleed: used during cruise and high-power conditions
  • HP (High-Pressure) compressor bleed: used during start, low power, and high-altitude conditions
  • APU bleed air: ground operations and in flight up to ~FL200. Does not require precooling. Not available for anti-ice.
  • HP and LP cannot be used simultaneously. PCB logic selects automatically.
  • HP/LP selection logic factors: WOW · Throttle Lever Angle (TLA) · Aircraft altitude · Anti-ice systems ON/OFF
  • Single-engine operation: bleed air from one engine sufficient to maintain all pneumatic system functions.
  • Engine bleed air precooled by N1 bypass air in heat exchanger before entering fuselage.
  • Ozone converters in bleed-air lines improve environmental air quality.
🔍 Bleed-Air Leak Detection — 6 Zones
  • L/R Wing anti-ice zones: if overtemp → closes wing anti-ice valves → CAS WING BLEED LEAK L/R
  • L/R Supply bleed-leak zones: if overtemp → closes pylon valve + wing anti-ice valve + stab anti-ice valve + flow control valve → CAS SUPPLY BLEED LEAK L/R
  • Stabilizer anti-ice zone: if overtemp → closes left AND right stab anti-ice valves → CAS STAB BLEED LEAK
  • ACM bleed-leak zone: if overtemp → closes mass flow valves + APU BCV → APU shuts down (cannot start) → Emergency pressurization activates → CAS ACM BLEED LEAK + EMERGENCY PRESSURIZATION
All leak CAS messages PERSIST even after the sensor cools — they do not self-extinguish.
🔧 Service Air System (25 PSI)
  • Available from either operating engine or APU when running
  • Passes through 25 PSI pressure regulators
  • Uses: Rudder bias actuator heat (early aircraft) · ACM water separator aspiration · Outflow valve vacuum ejector (pressurization) · Acoustic door seal · Baggage compartment heat (via left engine bleed → precooled)
  • Baggage heat: left engine precooled bleed heats unpressurized tail cone compartment. Bleed air mixes with compartment air before exhausting through distribution ducts.
  • Baggage heat valve auto-closes if smoke detected in baggage compartment.
10
ICE AND RAIN PROTECTION
Bleed Air Anti-Ice · Electric Heat · Ice Detection · Rain Removal
+10°C
RAT at or below + visible moisture = icing conditions
–35°C
Lower limit for anti-ice requirement (with visible moisture)
180 KIAS
Minimum speed in icing — except approach/landing
PREVENT
Anti-ice designed to prevent — NOT remove accumulated ice
💨 Bleed-Air Anti-Ice Protection
  • Wing leading edges: inboard sections — bleed air via PRSOV. Temperature sensors monitor for over/undertemp conditions.
  • Horizontal stabilizer leading edges: L and R independent — bleed air via dedicated SOVs.
  • Engine nacelle lip heat: bleed air
  • Nose cone heat: bleed air
  • Engine stator vane heat: dedicated P2.8 bleed air (separate from other anti-ice systems)
  • ENGINE/STAB L/R buttons: deenergize valves OPEN when selected ON. With button OFF: each anti-ice valve is energized closed by main DC power.
  • Outboard wing anti-ice: separate outboard PRSOV — additional wing leading edge protection.
  • Stabilizer crossflow SOV: normally closed — for X-flow between L/R stab systems.
Warm-up CAS messages (cyan, ground only): ANTI-ICE ON ENGINE/STAB · ENGINE ANTI-ICE COLD L/R · STAB ANTI-ICE COLD L/R · INB WING A/I COLD L/R — all extinguish once surfaces reach operating temperature. Inhibited in air.
⚡ Electrical Anti-Ice and Heating
  • Windshields (main L/R): AC power from alternators — 3 heated zones per windshield, each using one phase of AC. Inoperative when engines are shut down.
  • Left alternator supplies: two outboard panels of left windshield + inboard panel of right windshield + right forward side window.
  • Right alternator supplies: opposite panels. Loss of either alternator does NOT cause total loss to a windshield — each alternator covers specific panels on BOTH windshields.
  • Temperature sensors: imbedded in each windshield center and outboard panel — monitor for overheat. CAS WINDSHIELD OVERTEMP L/R + WINDSHIELD HEAT INOP L/R if overtemp detected.
  • CAS AC BEARING L/R: respective alternator may experience bearing failure within ~20 hours.
  • Pitot/static system: 3 independent electric systems (L, R, Standby). Buttons on ANTI-ICE panel. CAS PITOT/STATIC COLD L/R/STBY: on ground with buttons OFF; amber in flight with buttons OFF.
  • AOA vanes and cases: electrically heated. Cases: main DC via AOA CASE HEAT CBs — heat ON anytime avionics are ON.
  • RAT probes: electrically heated when ENGINE/STAB buttons are ON. CAS RAT HEAT FAIL L/R if probe not receiving current.
🌧️ Rain Removal and Ice Detection
  • Rain repellent: permanent Surface Seal™ coating on windshields — effective during flight. No other compounds authorized.
  • Windshield fan (W/S FAN button): two-speed blower in nose compartment. AUTO low speed for avionics cooling. High speed (W/S FAN ON) for ground rain removal.
  • Windshield ice detection lights (2 red LEDs, glareshield): aimed at unprotected area near inboard edge of each windshield. When ice forms → red glow visible. Active in NIGHT mode.
  • Wing inspection lights: two lights per side forward of wing root — illuminate outboard leading edges for night ice detection.
Icing operations: anti-ice must be ON and operating BEFORE entering icing conditions. Equipment not approved for freezing rain or severe mixed/clear ice. Prolonged operation with gear/flaps down not recommended in icing.
11
AIR CONDITIONING
ECU · ACM · Heat Exchangers · Water Separator · Temperature Control
❄️ Air Conditioning Flow Path
Engine/APU bleed air
→
Pylon precooler
→
Primary Heat Exchanger (cools with ram air)
→
ACM Compressor (compresses + heats)
→
Secondary Heat Exchanger (cools again)
→
ACM Turbine (expands → very cold)
→
Water Separator → cockpit/cabin ducts
Single engine can maintain all environmental and pressurization requirements under most operating conditions.
⚙️ ECU Components
  • Air-Cycle Machine (ACM): single shaft drives fan + compressor + turbine. Fan pulls ram air across heat exchangers (exhaust out right fuselage vent). Compressor and turbine on same shaft — rapid expansion in turbine creates very cold air.
  • Primary HX: cools incoming bleed air before ACM compressor using ram air.
  • Secondary HX: cools compressed air from ACM compressor using ram air, before turbine.
  • Water Separator: removes condensation from cold air after turbine expansion. Extracted water sprayed over heat exchangers. Bypass temp valve prevents freezing at separator. If water freezes: internal relief valve maintains airflow to cabin.
  • Temperature control valves: mix hot bleed air with cold ACM output for desired temperature. Auto or manual control.
  • Recirculation fan: recirculates cabin air through the system.
🌡️ Temperature Control
  • 3 distribution ducts: overhead (cold ECU air) + floor + sidewall (warm bleed mixed with cold)
  • Control panel: cockpit or remote cabin panel. AUTO or MANUAL mode.
  • APU bleed air: below ~FL200, APU can supply all environmental air. Above FL200: engine bleed pressure exceeds APU → engine bleed takes over automatically.
  • APU bleed does NOT need precooler — already below 475°F / 246°C.
  • Check valve in ductwork prevents reverse flow between APU and engine ducts.
  • Ozone converters: in engine bleed-air lines — improve air quality for cabin.
12
PRESSURIZATION
Outflow Valves · Electronic Controller · Modes · Limits · CAS
8,000 ft
Nominal cruise cabin altitude
14,250 ft
Max cabin altitude (±250 ft) — limiters
9.6 psid
Max ΔP — outflow valve relief
14,500 ft
Cabin altitude → O₂ auto-deploy (±490 ft)
⚙️ Outflow Valves — How Pressurization Works
  • 2 interconnected outflow valves on lower aft pressure bulkhead. Work together.
  • More open = cabin altitude RISES (pressure escapes to unpressurized tail cone).
  • More closed = cabin altitude DESCENDS (pressure builds up).
  • Primary outflow valve: servo-type torque motor metering valve driven by electronic pressure controller via vacuum from service air vacuum ejector.
  • Secondary outflow valve: pneumatically interconnected — follows primary. In MANUAL mode: crew controls secondary via CABIN ALT lever; primary follows secondary.
  • Cabin door seal: uses differential pressure between cabin and outside atmosphere to seal against door frame.
  • Max altitude limiters: prevent cabin altitude above 14,250 ±250 ft. Poppet valve on each outflow valve opens to allow cabin air into control chamber — overrides vacuum, forcing valves to close. Works in AUTO and MANUAL.
  • Max ΔP limiters: if controller malfunctions and causes uncontrolled pressure increase: relief mechanism opens when ΔP reaches 9.6 psid — outflow valves open.
  • Static ports: Left static port → primary outflow valve. Right static port → secondary outflow valve. Both sense atmospheric pressure for ΔP limiters.
Pre-pressurization on takeoff roll: when L throttle advances beyond 82.5% N2, controller signals outflow valves to begin closing → cabin altitude descends ~180 ft below field elevation before liftoff. Prevents pressure fluctuations at rotation.
🎛️ Control Modes
  • AUTO / NORM: controller follows pre-programmed cabin altitude vs. aircraft altitude schedule. Set "A" knob to departure or destination field elevation (inner scale). Automatic climb, cruise, and descent control throughout flight.
  • AUTO / ALT SEL: crew selects desired aircraft cruise altitude (outer scale) or desired cabin altitude (inner scale). Set rate with "R" knob. Controller climbs cabin at selected rate to selected altitude.
  • MANUAL: torque motor metering valve disabled. Secondary outflow valve controlled by CABIN ALT lever. Rate selector knob adjusts rate of change. Emergency bus power required.
  • High-altitude airfield mode: "A" knob set within yellow arc (8,100–14,000 ft cabin alt). Different schedule: cabin climbs to 8,000 ft during cruise (10 min stable OR 1,000 ft descent from peak), then adjusts per destination elevation during descent below FL245.
  • Rate multipliers for high-altitude landing: 8,000–11,000 ft: ×1.6. Above 11,000 ft: ×2.8 — ensures cabin is depressurized at touchdown.
  • Landing mode: if still pressurized at touchdown → squat switch logic → controller dumps pressure at scheduled rate for 60 sec. After 60 sec: full dump to atmosphere.
  • System self-test (FAULT light) when electrical power is first applied.
⚠️ Pressurization CAS Messages
CABIN ALTITUDE
Cabin altitude above 10,000 ft (normal) or above 14,500 ft (high-altitude airfield mode, below FL245). Aural "Cabin Altitude" voice warning. Triggers passenger oxygen auto-deployment if PASS OXY in AUTO above 14,500±490 ft.
CABIN ALT WARN
Cabin altitude approaching warning threshold. Amber precursor to red CABIN ALTITUDE.
PRESS CONTROLLER FAULT
Electronic pressurization controller fault — switch to manual or backup mode.
Emergency descent memory items: Oxygen masks DON + 100% · Autopilot OFF · Throttles IDLE · Speedbrakes 100% · Nose down ~15°
13
HYDRAULIC POWER SYSTEM
3,000 PSI · Engine-Driven Pumps · Auxiliary Pump · Consumers
3,000 PSI
Normal system operating pressure
2
Engine-driven hydraulic pumps (EDPs)
DC
Auxiliary pump power source (ground use only)
⚙️ System Architecture
  • Two Engine-Driven Pumps (EDP): one per engine AGB — primary power source. Either pump can supply full system pressure. Both run simultaneously during normal operations.
  • Auxiliary hydraulic pump: DC-powered, for ground use only. Used for ground checks and when engine-driven pumps not available on ground.
  • Single hydraulic system: all consumers draw from the same reservoir and return to the same reservoir.
  • Firewall shutoff valves: close when ENG FIRE button pressed — isolates hydraulic supply to that engine pylon. Thrust reverser is also disabled.
  • EICAS indications: system pressure (3,000 PSI nominal) and volume displayed. CAS HYD PRESSURE LOW L/R when pressure is low.
🔧 Hydraulic System Consumers
  • Landing gear retraction/extension
  • Main wheel brakes + antiskid
  • Nosewheel steering (NWS)
  • Speed brakes (ground + flight)
  • Spoilers (roll and speed brake)
  • Thrust reversers
  • Autopilot servos
  • Yaw damper
Loss of hydraulic pressure: loss of spoiler control → spoiler panels ratchet to stowed position. Landing gear cannot retract on emergency DC power. Brakes and NWS have pneumatic/accumulator backups.
14
LANDING GEAR AND BRAKES
Trailing-Link Tricycle · NWS · Brakes/Antiskid · Emergency Extension
🛬 Landing Gear Design
  • Trailing-link tricycle design — dual wheels on all three legs
  • Main gear: air-over-oil struts (nitrogen cushion). Trailing-link absorbs shock loads gradually.
  • Nose gear: retracts FORWARD, extends AFT — free fall assisted by slipstream
  • 6 heat shields per main wheel assembly; 3 thermal fuse plugs per wheel — rupture at high temp to prevent tire over-inflation from brake overheating
  • Tire chines on nose gear: deflect standing water away from engine inlets
  • Nose gear automatically centers on retraction for wheel well clearance
  • 3 squat switches (one per gear leg) — affect: FADEC ground/flight idle logic, thrust reverser operation, pressurization logic, NO TAKEOFF system, and other systems
  • Gear transit time: approximately 6 seconds to extend or retract
🔒 Locking Systems
  • Downlocks (internal): mechanical locking device in each actuator — engages at end of extend stroke. Internal microswitch illuminates green LH/RH/NO lights when locked down.
  • Uplocks: hook assemblies in each wheel well — hold gear retracted. Microswitch confirms each gear is in uplock. Once all three confirmed in uplocks: hydraulic pressure REMOVED, gear held mechanically.
  • Uplock release: hydraulic pressure OR pneumatic pressure OR manual cable (from aft cabin in total hydraulic + pneumatic failure).
  • Red UNLOCK annunciator: gear position does NOT agree with handle position. Extinguishes only when all three gears confirm either all-down-locked or all-up-locked.
  • Gear retraction inhibited on emergency DC power.
  • Ground safety lock: solenoid prevents handle moving to UP unless nose gear + one main gear indicates air mode.
⚠️ Gear Warning Horn

Warning horn activates for any of three conditions:

🆘 Emergency Extension Methods
  • Method 1 — Pneumatic blowdown: Red blowdown handle (right of center pedestal, below gear handle) pulls cable to discharge nitrogen bottle in nose compartment → pressure released into gear hydraulic lines → gear extends. Handle can be returned to stowed position after use.
  • Method 2 — Manual nose gear release: Red "D"-ring handle (next to blowdown knob) — pulls nose gear uplock away from roller. Gear free-falls due to gravity + slipstream.
  • Method 3 — Main gear manual release: Lever below lavatory closet — pulls two cables simultaneously, disengages main gear uplock hooks. Both main gears free-fall. Must be checked STOWED during cabin preflight.
Manual methods: used only if pneumatic blowdown unsuccessful.
🛞 Nosewheel Steering (NWS)
  • Rack-and-pinion NWS unit at top of nose gear — hydraulically powered
  • Tiller (left side of cockpit): large steering angle — for taxi. Spring-loaded to center on release.
  • Rudder pedals: smaller steering angle — for takeoff and landing roll
  • Combined (tiller + pedals): maximum angle 85 ± 2°
  • Taxi lights rotate WITH steering (on nose gear lower barrel)
  • After takeoff with gear UP: NWS unit hydraulically centers nosewheel
  • AP/TRIM/NWS DISC button: shuts off hydraulic pressure to NWS during press-and-hold. Use to deactivate NWS for flight control check.
  • NWS accumulator: allows limited steering in event of complete hydraulic failure
  • NWS available on ground: gear indicating ground mode, with engine or auxiliary pump pressure
  • Torque link MUST be disconnected for towing — failure to do so may damage steering unit
🛑 Brakes and Antiskid
15
FLIGHT CONTROLS
Roll · Pitch · Rudder · Flaps · Speed Brakes · Gust Lock · NO TAKEOFF
✈️ Flight Control Surfaces Overview
  • Roll: Ailerons (mechanical, cable/pulley) + Roll spoilers (panels 2,3,4 and 7,8,9 — hydraulic)
  • Pitch: Elevators (mechanical, cable/pulley) on movable horizontal stabilizer + Elevator tab system + Mach trim tabs
  • Yaw: Rudder (conventional, cable/pulley) + Rudder bias system
  • Flaps: Electric, 4 positions: UP · 5° · 15° · 35°
  • Speed brakes: 10 panels on wings (5 per side) — hydraulic. Full deployment: all panels 1–10. Modulated: panels 2–4 and 7–9.
  • Trim: Electric for all axes. Primary pitch: control wheel switches. Secondary pitch: center pedestal (backup).
  • Gust lock: T-handle under pilot tilt panel
  • Pitch/roll disconnect: T-handle — allows pitch and roll to operate independently
🔁 Roll Controls — Aileron + Spoilers
  • Ailerons: full deflection below 158 KIAS. Between 158–270 KIAS: aileron ratio changer reduces deflection proportionally (reduces control loading at high speed). Autopilot roll servo in aileron cable system.
  • Roll spoilers: NOT affected by aileron ratio changer — deployment always proportional to control wheel input. Controlled by spoiler mixer box via hydraulic actuators. Loss of hydraulics → spoilers RATCHET to stowed position.
  • EICAS display (ground only): SPD-BRK/SPOILERS section shows 6 panels (3 per side). In flight: roll spoiler display disabled.
  • Aileron trim: green band displayed on EICAS on ground. Must be in green range before takeoff — if out of range: indicator turns amber, contributes to NO TAKEOFF. In flight: green band not displayed, pointer remains white.
⬆️ Pitch Controls — Stabilizer + Elevators
  • Two independent elevators on trailing edge of movable horizontal stabilizer. Left control column drives left elevator, right drives right — interconnected for normal operation.
  • Primary pitch trim: electric, both primary trim switches on control wheels must be pressed SIMULTANEOUSLY to activate. Either pilot primary switches have PRIORITY over autopilot → AP disengages when pressed.
  • Stabilizer travel: +1.2° to –6.9° range.
  • Flap/stabilizer interconnect: when flaps move between 15°–35° in flight → primary trim system automatically trims stabilizer. Not active on ground.
  • Elevator tab system: mechanically linked to stabilizer — tabs fair with stabilizer as it moves. Stabilizer full leading-edge down → maximum tab down deflection (check during preflight).
  • Mach trim system: adjusts elevator tabs above 0.77 Mach. Deflects flow tabs down → trailing edge of elevator raised → aircraft pitch-up. Max 1° down deflection. Active with or without AP. CAS MACH TRIM FAIL if fault detected.
  • Secondary trim: backup if primary fails. Slower than primary. Requires emergency bus power. No AP trim available during secondary trim operation.
🦿 Rudder and Rudder Bias
  • Conventional rudder system — cable and pulley from rudder pedals
  • Yaw damper: autopilot rudder servo in rudder cable system
  • Rudder bias system: automatically deflects rudder during single-engine operations to reduce pilot pedal force. NORM/OVERRIDE button. Late production aircraft have updated bias system.
  • T/R UNLOCK (3–4 locks open in flight): rudder bias moves to minimum position → significantly increased pedal force required for single-engine ops.
  • Electric rudder trim via secondary trim panel
🚀 Flaps and Speed Brakes
  • Flaps (4 positions): UP · 5° (approach) · 15° (approach) · 35° (landing). Electric drive. RESET button available if fault. Flap position displayed on EICAS.
  • Speed brakes (10 panels): speed brake handle on center pedestal. STOW = deadband. Pull aft = modulated deployment (panels 2–4, 7–9). Full detent = ALL panels 1–10 deploy.
  • CAS SPEED BRAKES (amber): any panel not stowed below 500 ft RA in flight.
  • Panels not stowed on ground: contribute to NO TAKEOFF warning.
⛔ NO TAKEOFF Warning System

System prevents takeoff with incorrect configuration. Activated when T/O power set on ground with certain conditions present. Aural "No Takeoff" warning + CAS messages on MFD.

NO TAKEOFF CONDITIONS — KEY ITEMS
GUST LOCKGust lock T-handle not properly stowed (CAS GUST LOCK ON)
FLAPSFlap position outside takeoff range
STAB TRIMStabilizer trim out of green takeoff range
SPOILERSAny speedbrake/spoiler panel not stowed
AILERONAileron trim out of green range
Gust lock behavior: with gust lock engaged, LEFT throttle can only advance midway between IDLE and CRU detents — physically prevents T/O power on locked aircraft.
16
AVIONICS — PRIMUS EPIC®
Honeywell Primus EPIC · Displays · AFCS · FMS · TCAS · TAWS · Reversions
🖥️ Display Configuration — 4 LCDs
  • DU1 — Left PFD: pilot primary flight display — attitude, airspeed, altitude, HSI, flight director, approach guidance
  • DU2 — Center upper (EICAS): default position. Engine indications (N1/N2/ITT/oil), CAS messages, electrical, hydraulics, fuel, flaps, trim, speed brakes, pressurization. Can be moved to DU3 via reversion panel.
  • DU3 — Center lower (MFD): FMS pages, TCAS display, TAWS/terrain, weather radar, checklists, vertical profile, map
  • DU4 — Right PFD: copilot primary flight display
  • Controls: 2 MCDUs (left and right) + 2 CCDs (cursor control devices on center pedestal)
  • ASCB (Avionics Standard Comm Bus): bidirectional high-speed network connecting all MAUs, DUs, MRUs. Also uses ARINC 429 for non-ASCB components.
  • MAU cooling: replaceable cooling fans within each MAU cabinet
  • CMS (Central Maintenance System): integrated diagnostics and fault recording
  • SSDFR: solid-state flight data recorder
  • EICAS colors: Green = normal range. Amber = outside normal (caution). Red = exceedance. White = information. Analog pointer takes color of corresponding digital background.
🎯 Integrated Systems
  • AFCS (Automatic Flight Control System): autopilot + dual flight directors + yaw damper. Dual actuator I/O (lanes 1A/1B, 2A/2B). GP-400 guidance panel. SM-1000 servos (aileron, elevator, rudder). Pitch trim servo.
  • Dual FMS: Honeywell GPS-based. Dual GPS receivers. LNAV/VNAV capable. FMS status and active flight plan displayed on MFD.
  • TCAS II: traffic collision avoidance — TA (Traffic Advisory) and RA (Resolution Advisory). Display on PFDs and MFD.
  • TAWS (Terrain Awareness Warning System): enhanced GPWS modes. Terrain display on MFD.
  • Weather radar: WU-880 with WC-880 controller.
  • Radio altimeter: RT-300 — provides RA input to TCAS, gear warning, speed brake warnings, and minimums alerts.
  • Dual AHRS: attitude and heading reference system.
  • Dual ADC (AZ-200): air data computer — left in left nose, right in right nose. Digitizes pitot-static inputs for MAU processing.
  • Lightning detection: LP-850 processor + AT-850 antenna (optional)
🔄 Display Reversions
  • NORM: standard operation — DU1 = L PFD, DU2 = EICAS, DU3 = MFD, DU4 = R PFD
  • LEFT EMER: L PFD assumes EICAS function in addition to PFD data
  • RIGHT EMER: R PFD assumes EICAS function
  • OFF/REV: display reversed (inverted display)
  • PFD/MFD/EICAS reversion selector: on each instrument panel — ADC and ATT/HDG source selection
  • EICAS can be moved between DU2 and DU3 with EICAS LEFT/RIGHT button on reversion panels (avionics must be ON).
  • EICAS MISCOMPARE: wraparound test — compares values sent to EICAS vs. displayed. Mismatch → flashing amber on both PFDs right of HSI. Cross-check standby instruments.
V-speed identifiers and flap speed limits tables are in Chapter 16 (Table 16-1, 16-2) — reference for EICAS speed tape color coding and bug settings.
17
OXYGEN SYSTEM
Crew EROS Masks · Passenger Drop Boxes · Cylinders · Limitations
76 ft³
Standard cylinder (×1 or optional ×2)
36–70 PSI
Regulated delivery pressure
14,500 ft
Cabin altitude — auto passenger O₂ deploy
40,000 ft
Maximum cabin altitude for oxygen system
👨‍✈️ Crew Oxygen System
  • 2 EROS (Emergency Rapid Donning) masks — pilot and copilot. Quick-donning design with integrated smoke goggles.
  • Oxygen NOT normally required: pressurization maintains cabin altitude sea level to 8,000 ft.
  • Memory items — Cockpit/Cabin Smoke or Fire: Oxygen masks + goggles → DON + 100% · Establish communication · L and R MIC SEL buttons to MASK
  • Memory items — Loss of Cabin Pressure: Oxygen masks → DON + 100% · L and R MIC SEL to MASK · Emergency Descent — AS REQUIRED
  • Portable walkaround bottle: 11 ft³ — for individual emergency use
  • Extended range option: second 76 ft³ cylinder
👥 Passenger Oxygen System
  • Drop boxes in cabin/lavatory headliner — 2 masks per box. Standard: 9-passenger config. Up to 12-passenger optional.
  • PASS OXY knob (cockpit): AUTO = drops automatically above 14,500 ±490 ft cabin altitude. ON = manual deploy.
  • Sequence regulator: in low-pressure oxygen lines.
    — Cabin alt 14,500–26,000 ft: 36–41 PSI + momentary surge to 70 ±10 PSI (unlocks drop boxes)
    — Cabin alt above 30,000 ft: full 70 ±10 PSI to passenger masks
  • Lanyard: attached to mask — must be pulled to start oxygen flow through the mask. Flag helps identify mask in drop box.
  • Pilot can manually deploy passenger oxygen at any time with PASS OXY knob.
  • Emergency bus condition: PASS OXY knob auto-deploys at 14,500 ft in AUTO. Manual deploy via ON position still available.
🔧 System Components and Preflight
18
WEIGHT AND BALANCE
Formulas · Weight Categories · CG Limits · Balance Limits
📐 Essential Formulas
Weight × Arm = Moment
Arm = Moment ÷ Weight
CG Shift = (Weight Shifted × Distance Shifted) ÷ Total Weight
⚖️ Weight Definitions — Hierarchy
  • MEW (Manufacturer's Empty Weight): structure + powerplants + systems + fixed equipment
  • Standard BEW: MEW + standard items (unusable fuel, engine oil, toilet fluid, charged fire extinguisher, all hydraulic fluid, trapped fuel)
  • BEW (Basic Empty Weight): Standard BEW + installed optional equipment
  • Useful Load: Max Design Taxi Weight − BEW (includes payload + usable fuel)
  • Operational Takeoff Weight: max authorized for start of takeoff roll
  • Operational Landing Weight: max authorized for landing — subject to brake energy limits
  • Usable Fuel: fuel available for propulsion
  • Unusable Fuel: fuel remaining after fuel run-out test — part of standard items
⚠️ CG Limits — Effects
  • CG too far FORWARD: aircraft nose-heavy → may not be able to rotate at Vr or flare for landing. More stability, less maneuverability.
  • CG too far AFT (out of limits): significantly reduced stability → stall recovery may be IMPOSSIBLE. Never operate beyond aft limits.
  • Forward CG: more stable — larger horizontal stabilizer download required to balance → more drag
  • Aft CG: less stable — closer to neutral point → reduced pitch damping
  • CG limits envelope graph provided with aircraft on delivery (Cessna form). Must be consulted for each flight.
  • Weight addition/removal formula: ΔCG = (Weight Change × Arm Distance) ÷ New Total Weight
19
FLIGHT PLANNING AND PERFORMANCE
FAR Part 25 · Climb Gradients · Takeoff · Landing · V-Speeds
📊 FAR Part 25 Climb Gradients
SegmentMinimum GradientConfiguration / Condition
1st Segment0% grossGear still retracting, flaps at T/O position, one engine inoperative (OEI)
2nd Segment1.6% net (OEI)Gear UP, flaps T/O, at V2 + power. Most limiting segment for max T/O weight.
3rd SegmentN/AAcceleration at level flight, flap retraction to clean, speed increase
Final (Enroute)1.2% grossClean configuration, cruise altitude, OEI
Important: Max T/O weight from climb requirements chart guarantees ONLY 2nd segment performance — does NOT guarantee other segments or obstacle clearance.
✈️ Takeoff Performance Calculation
  • Determine gross weight + obtain airport data (runway, temp, pressure alt, wind, gradient, obstacles)
  • Verify temp within ambient limits
  • Calculate crosswind/headwind component
  • From T/O gross weight: determine TOFL and V-speeds for DRY conditions (AFM Section IV)
  • Correct for runway gradient (rise/runway length × 100)
  • If contaminated runway: AFM Section VII advisory corrections
  • Compare available runway length vs. calculated TOFL → if insufficient: reduce weight
  • Calculate 2nd segment OEI climb gradient (AFM Section IV) → if not met: reduce weight
🛬 Landing Performance Calculation
  • Determine landing weight at arrival (after fuel burn)
  • Obtain destination airport data + check brake energy limits
  • Calculate go-around thrust (approach + landing climb gradient for OEI)
  • If contaminated runway: AFM Section VII corrections
  • FAR 135 operations: divide calculated landing distance by 0.6 (requires 67% excess runway)
  • If landing weight exceeds limit: must burn off fuel prior to landing
  • Check approach climb gradient (OEI) and landing climb gradient (all engines) for go-around capability
📚 Performance Data Sources
SourceData Contained
AFM Section IVT/O field length, V-speeds, 2nd segment OEI climb gradient, landing field length
AFM Section VII (Advisory)Contaminated/adverse runway corrections, climb gradient details
Performance ManualClimb, cruise, and descent performance data
RUNWAY SLOPE / CLIMB RATE FORMULAS
Gradient (%) = (Elevation Change ÷ Runway Length) × 100
Climb Rate (fpm) = Groundspeed × Gradient% × (6,076 ÷ 100)
Citation Sovereign CE-680 · PTM Rev 5.0 · FOR TRAINING PURPOSES ONLY
This guide does not supersede the AFM, manufacturer's flight manuals, or regulatory publications.
Created by Leonardo Maia · Version 2.0
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KNOWLEDGE TEST
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CAS MESSAGE INDEX
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GLOSSARY
Key terms and acronyms used throughout the PTM