01
AIRCRAFT GENERAL
Specifications · Dimensions · Operating Speeds · Configuration
🔢 KEY SPECIFICATIONS
550 SHP
PT6A-21 Flat-rated power
10,100 lbs
C90B Max Takeoff Weight
9,650 lbs
C90A Max Takeoff Weight
384 gal
Total usable fuel capacity
226 KIAS
VMO Max Operating Speed
13
Max occupants (FAA cert.)
✈️ C90A WEIGHTS
| Limit | Value |
|---|---|
| Max Ramp (LJ1138+) | 10,160 lbs |
| Max Takeoff (LJ1138+) | 10,100 lbs |
| Max Takeoff (LJ1063-1137) | 9,650 lbs |
| Max Landing (LJ1138+) | 9,600 lbs |
| Max Landing (LJ1063-1137) | 9,168 lbs |
| Rear Baggage | 350 lbs max |
| Nose Baggage/Avionics | 350 lbs max |
✈️ C90B WEIGHTS
| Limit | Value |
|---|---|
| Max Ramp | 10,160 lbs |
| Max Takeoff | 10,100 lbs |
| Max Landing | 9,600 lbs |
| Max Zero Fuel | No structural limit |
| Rear Baggage | 350 lbs max |
| Nose Baggage/Avionics | 350 lbs max |
🚀 OPERATING SPEEDS
⚡ C90A SPEEDS
| Speed | Value |
|---|---|
| VMO | 226 KIAS |
| VA (maneuvering) | 153/169 KIAS |
| VLO Extension/Extended | 182 KIAS |
| VLO Retraction | 163 KIAS |
| VFE Approach | 184 KIAS |
| VFE Down | 148 KIAS |
| VS (100% flaps, pwr off) | 76 KIAS |
| VMCA (air min control) | 90 KIAS |
⚡ C90B SPEEDS
| Speed | Value |
|---|---|
| VMO | 226 KIAS |
| VA (maneuvering) | 169 KIAS |
| VLO Extension/Extended | 182 KIAS |
| VLO Retraction | 163 KIAS |
| VFE Approach | 184 KIAS |
| VFE Down | 148 KIAS |
| VS (100% flaps, pwr off) | 78 KIAS (4-blade prop) |
| VMCA (air min control) | 80 KIAS (4-blade prop) |
📐 DIMENSIONS & CONFIGURATION
📏 CABIN DIMENSIONS
| Cabin Width (max) | 54 inches |
| Cabin Length (partition to partition) | 155 inches |
| Cabin Height (max) | 57 inches |
| Airstair door width (min) | 27 inches |
| Airstair door height (min) | 51.6 inches |
| Pressurized compartment volume | 313.6 cu ft |
| Rear baggage compartment | 53.5 cu ft |
| Nose avionics/baggage | 16 cu ft |
| Wing area | 293.94 sq ft |
🔧 C90B DISTINCTIONS vs C90A
- 4-blade propeller: 90-inch Hartzell (LJ-1542+) or McCauley, dynamically balanced
- Gated ground fine: Selectable zero-thrust position for improved ground handling
- Flap selector: Super King Air 350 follow-up type (Up/Approach/Down)
- 26 dynamic vibration absorbers: 12–15 dB noise/vibration reduction
- Chip detect: Caution (amber) vs C90A warning (red)
- Digital OAT system: Similar to Super King Air 300/350
- Avionics bay moisture barrier: Improved avionics reliability
🔍 EXTERNAL INSPECTION ITEMS
🔍 KEY PREFLIGHT ITEMS
- Propeller tiedown boots: Must be removed before flight – installed over blade tips during storage
- Fuel quantity: Nacelle tanks first (filler on top of nacelle), then leading edge wing tanks
- Engine air inlet: Pitot-type intake; check for obstructions, ice vanes free
- Oil check: Dipstick on engine oil filler; check level per limits
- Hydraulic reservoir: Located in left center wing section; check level via dipstick
- Propeller clearance: 4-blade C90B has generous tip-to-ground clearance
- Danger areas: Engine exhaust, propeller arc zones front and rear; 15 ft lateral
ℹ️ Aircraft Configuration: The King Air C90A and C90B are certificated for up to 13 occupants FAA-certified, with the most popular configuration providing 6 passengers + 2 crew. Minimum certified crew is 1 pilot.
02
ELECTRICAL POWER SYSTEMS
DC Generation · Battery · Buses · Inverters · External Power
🔢 KEY VALUES
28 VDC
Nominal system voltage
250 A
Each starter/generator rating
34 Ah
Ni-Cd battery (pre LJ-1534)
42 Ah
Lead-acid battery (LJ-1534+)
28.25 V
Normal system potential ±0.25V
7 amps
BAT CHARGE caution threshold
⚡ SYSTEM OVERVIEW
⚡ ELECTRICAL ARCHITECTURE
The system is a 28-VDC (nominal) system with negative lead grounded to the airplane structure. Power sources are two 250-amp starter/generators connected in parallel, plus one battery. A multi-bus system distributes power.
Left Generator
→
L Gen Bus
→
Triple-Fed Bus
Right Generator
→
R Gen Bus
→
Triple-Fed Bus
Battery
→
Hot Battery Bus
→
Triple-Fed Bus
🔌 BUS STRUCTURE
📋 LEFT GENERATOR BUS
- Flap motor & control
- L Landing light, L Main Anti-ice (ice vane)
- L Chip detector, L Engine fuel control heater
- No. 1 Inverter Power Control/Select
- Pilot windshield anti-ice, Vent blower
- R Firewall valve, R Fuel boost pump
- Crossfeed, Rotating beacon lights
- Avionics: Comm 2, ADF 1, Autopilot, Transponder 2
📋 RIGHT GENERATOR BUS
- R Landing light, R Main Anti-ice (ice vane)
- R Chip detector, R Engine fuel control heater
- Rudder boost, No. 2 Inverter Power Control/Select
- Copilot windshield anti-ice, Strobe lights
- R Pitot heat, Stall warning heat
- L Firewall valve, L Fuel boost pump
- Avionics: Nav 2, Transponder 1, Compass 2
📋 CENTER BUS
- Avionics annunciator, Generator reset
- Pneumatic surface deice, Windshield wiper
- Taxi light, Icing light
- No. 1 & 2 Inverter Power Control
- Prop deice power & control
- Air conditioner, Normal/Max heat (electric)
- Landing gear motor
📋 TRIPLE-FED BUS & HOT BATTERY BUS
- Triple-fed bus: Powered from battery AND both generator buses (white ring on switches)
- Hot battery bus: ALWAYS powered regardless of battery switch position
- Hot battery bus items: Fire extinguisher switches, emergency items
- Identification: White ring on cockpit panel around switches powered by center/triple-fed bus
🔋 BATTERY
🔋 BATTERY DETAILS
- Location: Right wing center section (also hot battery bus)
- Pre LJ-1534: 34 Ah, 20-cell, nickel-cadmium (NiCd), air-cooled
- LJ-1534 and after: 42 Ah, sealed, lead-acid
- Battery switch: Pilot's left subpanel – closes battery bus tie and relay
- BAT CHARGE annunciator: Charge rate exceeds 7 amps for 6 seconds (pre LJ-1534)
- Min voltage for ext power start: Must consult POH – generally 20+ volts
- Leave battery ON during ext power start: Protects against voltage spikes
- Overhead meter panel: Voltmeter indicates center bus voltage
🔌 GENERATORS & CONTROLS
⚡ GENERATORS
- Type: Starter/generators – function as both starter and generator
- Rating: 28V, 250 amps each
- Generator switches: Under gang bar on pilot's left subpanel
- Turn on: Move switch to ON position
- Offline annunciator: Amber DC GEN with load meter indicating no output (LJ-1353+); Red prior to LJ-1353
- Load meters: Overhead meter panel – show % load on each generator
- Start sequence: After starting right engine, turn right gen ON; wait for loadmeter to drop to ~25% before starting left engine
🔌 EXTERNAL POWER
- Location: Right forward portion of fuselage
- Min continuous current: 300 amperes capability required
- EXT PWR annunciator: Flashing – alerts operator plug is connected
- Use: Ground power unit must provide continuous 300A
- External power relay (EPR): Routes external power to system
🔄 INVERTERS (AC POWER)
🔄 AC INVERTERS
- Rating each: 115V and 26V, 400 Hz
- Two inverters installed: Either can power AC loads
- INVERTER switch location: Pilot's left subpanel
- INV FAIL annunciator (red): Selected inverter is inoperative, or both are off
- No. 1 Inverter power: L Gen bus control, Center bus power
- No. 2 Inverter power: R Gen bus control, Center bus power
- AC loads: Gyros, avionics requiring AC, pitot heat (some models)
⚠️ STARTER LIMITS
⚠️ STARTER DUTY CYCLE LIMITS: 40 sec ON → 60 sec OFF → 40 sec ON → 60 sec OFF → 40 sec ON → then 30 min OFF before attempting again.
🔴 BUS TIE & BAT TIE ANNUNCIATORS
⚠️ BAT TIE ANNUNCIATOR
- Illuminates when: Battery is isolated from generator buses and center bus
- If center bus shows 28V: Bus is OK — can reset BAT TIE using bus sense switch
- If center bus shows LOW voltage: Do NOT reset – bus may have a short
⚠️ L/R BUS TIE ANNUNCIATORS
- L BUS TIE illuminates: Left generator bus isolated from center bus
- R BUS TIE illuminates: Right generator bus isolated from center bus
- Each generator bus tie can be manually opened with switches on pilot's subpanel
⚠️ ANNUNCIATORS — ELECTRICAL
INV FAIL
Selected inverter is inoperative, or both inverters are off.
→ Select alternate inverter; if both fail, AC-powered equipment (gyros) unavailable
DC GEN L/R
Generator is off line (amber LJ-1353+; red prior to LJ-1353). Load meter indicates no output.
→ Reset generator; if fails, continue single-generator ops per checklist
BAT TIE
Battery is isolated from generator buses. Check center bus voltage before resetting.
→ If 28V on center bus: reset. If low: do not reset – possible short
L/R BUS TIE
Generator bus isolated from center bus. Generator bus items unavailable.
→ Check associated generator; manually close bus tie if appropriate
BAT CHARGE
Battery charge rate exceeds 7 amps for 6 seconds (pre LJ-1534 NiCd battery). Indicates possible overcharge.
→ Monitor; indicates battery accepting heavy charge or possible malfunction
EXT PWR
External power plug is connected to the airplane. Advisory only – no action required unless not desired.
03
LIGHTING
Cockpit · Cabin · Exterior · Landing Lights
💡 EXTERIOR LIGHTS
- Landing lights: In nacelles under landing gear; extinguish manually after takeoff
- Taxi light: Nose gear assembly; CENTER BUS
- Recognition lights: In each wingtip
- Ice lights (inspection lights): On outside of engine nacelles (illuminate wing leading edge)
- Strobe lights: Pilot's right subpanel switch R GEN BUS
- Rotating beacon: L GEN BUS
- Tail flood lights: Optional; illuminate horizontal tail
💡 COCKPIT & CABIN LIGHTS
- Overhead light control panel: Rheostats for cockpit dim/bright
- Instrument EMERG LIGHTS: TRIPLE FED BUS
- Baggage light: HOT BATTERY BUS
- Cabin reading lights & sign chime: R GEN BUS
- Annunciator dim: Automatic when: generator on line, overhead floodlight OFF, master panel lights ON, pilot flight lights ON, low ambient light (photoelectric cell)
- APPROACH PLATE rheostat: Does NOT dim annunciators
💡 LIGHT SWITCHES LOCATIONS
| Light | Switch Location | Bus |
|---|---|---|
| Landing lights | Pilot's left subpanel | L/R Gen Bus |
| Taxi light | Pilot's left subpanel | Center Bus |
| Strobe lights | Pilot's right subpanel | R Gen Bus |
| Rotating beacon | Overhead panel | L Gen Bus |
| Navigation lights | Overhead panel | Various |
| Ice/inspection lights | Overhead panel | Center Bus |
| Instrument emerg lights | Overhead panel | Triple Fed Bus |
💡 Landing Light Note: After takeoff, landing lights do NOT extinguish automatically – the pilot must turn them off using the LANDING light switches. They are not automatic like some other aircraft.
ℹ️ LIGHTS UP Advisory: LIGHTS UP advisory annunciator illuminates when landing lights or taxi light is on with landing gear UP. This is an advisory only.
04
MASTER WARNING SYSTEM
Annunciator Panel · Warning/Caution/Advisory · PRESS TO TEST
🔴 SYSTEM OVERVIEW
⚠️ ANNUNCIATOR SYSTEM
The annunciator panel is centrally located in the glareshield. It contains word-readout annunciators in three colors:
RED — Warning
+
FAULT WARNING Flasher
AMBER/YELLOW — Caution
+
MASTER CAUTION Flasher (LJ-1353+)
GREEN — Advisory
→
No flasher triggered
🔴 FAULT WARNING FLASHER
- Located in glareshield in front of pilot
- Any red annunciator: Triggers flasher
- Extinguish flasher: Depress its face (even without clearing fault)
- Flasher re-activates: If additional red annunciator illuminates
- Red annunciator: Remains ON until fault is corrected
- FAULT WARNING flasher has NO dim mode
🟡 MASTER CAUTION FLASHER (LJ-1353+)
- Yellow flasher in glareshield
- Any yellow annunciator: Triggers MASTER CAUTION
- Yellow annunciator: Remains until fault corrected
- PRESS TO TEST switch: Illuminates ALL annunciators and FAULT WARNING flasher
- PRESS TO TEST located immediately to the right of annunciator panel
💡 DIMMING SYSTEM
💡 AUTOMATIC DIMMING
Annunciators automatically switch to DIM mode when ALL of the following conditions are met simultaneously:
- A generator is on line
- OVERHEAD FLOODLIGHT is OFF
- MASTER PANEL LIGHTS switch is ON
- PILOT FLIGHT LIGHTS are ON
- Ambient cockpit light (sensed by photoelectric cell in overhead panel) is below preset level
💡 Note: If any of these conditions is NOT met, BRIGHT mode is selected. A warning or caution annunciator will cause the dim mode to switch to bright.
🔴 WARNING ANNUNCIATORS
L/R FUEL PRESS
Low fuel pressure on indicated side. Check boost pump and crossfeed.
→ Crossfeed to AUTO or manually OPEN; check boost pump circuit breaker
INV FAIL
Selected inverter inoperative, or both inverters off. AC-powered instruments affected.
AP DISC
Autopilot disconnected by means other than pilot's disconnect button (LJ-1353+).
→ Verify airplane control; re-engage autopilot if desired
AP TRIM
Improper trim or no trim command from autopilot (LJ-1353+).
ALTITUDE WARN
Cabin altitude exceeds 10,000 ft (12,500 ft LJ-1353+).
→ Immediate oxygen use required per FAR; initiate emergency descent
DOOR
Cabin airstair door is open or not secure. Do not pressurize with door open.
NOSE DOOR
Nose baggage door not secure (pre LJ-1531).
L/R ENG FIRE
Fire detected in left or right engine compartment by photoconductive cell detectors.
→ Execute ENGINE FIRE checklist immediately
🟡 CAUTION ANNUNCIATORS
DC GEN L/R
Generator off line (amber LJ-1353+; red prior). Load meter shows no output.
NO FUEL XFR L/R
Left/right wing tank empty OR transfer pump failed.
→ Verify transfer pump; nacelle feeding directly from its own remaining fuel
PROP GOV
Propeller levers not in high RPM position with landing gear extended (safety reminder).
CHIP DETECT L/R
Metal contamination detected in engine oil. Red on C90A; amber on C90B.
→ C90A: monitor closely per checklist. C90B: monitor engine instruments; no emergency shutdown required if normal
ICE VANE L/R
Engine anti-ice vane in transit or inoperative (caution). Separate advisory when in icing position.
L/R BUS TIE
Generator bus isolated from center bus.
BAT TIE
Battery isolated from generator buses and center bus.
FUEL CROSSFEED
Crossfeed valve is receiving power (valve in motion or open).
HYD FLUID
Hydraulic fluid reservoir level is low.
→ Do not extend/retract gear repeatedly; plan for manual extension if needed
BAT CHARGE
Battery charge rate exceeds 7 amps for 6 seconds (pre LJ-1534 NiCd).
PITCH TRIM DISC
Pitch trim deenergized by trim disconnect switch while power switch on pedestal is ON.
EXT PWR
External power connector plugged in. Advisory (some versions amber).
🟢 ADVISORY ANNUNCIATORS
L/R AUTO IGN
System armed AND engine torque below 400 ft-lb, OR Ignition/Engine Start switch ON.
→ Normal during ignition test and low-power flight operations
L/R AUTOFTHR ARMED
Autofeather armed AND power levers advanced above 90% N1, OR autofeather test in TEST.
→ Normal – confirms autofeather system is armed and ready
L/R ICE VANE
Engine anti-ice vanes ARE in icing position (extended). Advisory confirming system active.
BUS TIE OPEN
Generator bus ties manually opened by pilot.
LIGHTS UP
Landing lights or taxi light is ON with landing gear UP. Advisory reminder to turn off lights.
05
FUEL SYSTEM
Tanks · Boost Pumps · Transfer · Crossfeed · Firewall Valves
🔢 KEY VALUES
384 gal
Total usable fuel (both wings)
192 gal
Each wing system capacity
61 gal
Nacelle tank (each side)
44 gal
Center section tank (each)
30 psi
Boost pump output pressure
10 hrs
Max suction feed (cumulative)
🛢️ FUEL TANK SYSTEM
🛢️ TANK LAYOUT — EACH WING
Each wing fuel system has 5 interconnected tanks – all bladder type:
| Tank | Capacity | Notes |
|---|---|---|
| Nacelle tank | 61 gal | Feeds engine; submerged boost pump here |
| Center section tank | 44 gal | Transfer pump at low point; feeds nacelle |
| Wing leading-edge tank | 40 gal | Gravity feeds center section |
| Outboard panel tank #1 | 23 gal | Gravity feeds inboard |
| Outboard panel tank #2 | 25 gal | Gravity feeds inboard |
| TOTAL each wing | 192 gal | Two filler caps per wing |
⚠️ Filling sequence: Fill nacelle tank FIRST, then wing tanks. A check valve prevents backflow from nacelle to wing tanks.
⚙️ FUEL FLOW PATHS
🔄 NORMAL FLOW PATH
Outboard tanks
→ gravity →
Center section tank
→ transfer pump →
Nacelle tank
→ boost pump ~30 psi →
Engine-driven pump
→
FCU → Engine
🔄 CROSSFEED (SINGLE ENG or BOOST PUMP FAIL)
Good-side nacelle
→ boost pump →
Crossfeed valve (AUTO opens)
→
Both engines supplied
🔧 COMPONENTS
🔧 BOOST PUMP
- Type: Submerged, rotary vane-type impeller; electrically driven
- Output: ~30 psi to engine-driven fuel pump
- Location: Submerged in each nacelle tank
- Circuit breaker: 10-amp, on fuel panel
- FUEL PRESS annunciator: Low pressure on that side – check boost pump
- Required: Needed to provide pressure to engine-driven high-pressure pump
🔧 TRANSFER PUMP
- Location: Low point of each center section tank
- Function: Transfers fuel from center section/wing to nacelle tank
- NO FUEL XFR annunciator: Illuminates if transfer pump fails OR wing tank is out of fuel
- Also used: In some crossfeed operations
- Low level switch: Located in nacelle tank – activates transfer pump automatically
🔧 CROSSFEED VALVE
- Switch positions: AUTO / OPEN / CLOSED
- NORMAL position: CLOSED (each engine from own side)
- AUTO: Opens automatically if boost pump pressure drops below ~10 psi
- Authorized for: Single-engine operation, or when a boost pump is inoperative
- NOT for: Routine fuel balance; NOT in closed during normal flight
- FUEL CROSSFEED annunciator: Valve receiving power (in motion or open)
🔧 FIREWALL SHUTOFF VALVES
- Purpose: Shut off fuel to engine in case of fire or emergency
- L Firewall valve: Powered by R Gen Bus
- R Firewall valve: Powered by L Gen Bus
- Cross-powered: Designed so engine fire doesn't prevent valve operation
- Location of switches: Fuel panel (pedestal)
🔴 SUCTION FEED OPERATION
⚠️ SUCTION FEED — LIMITATIONS
- Used when boost pump has failed
- Engine-driven high-pressure pump draws fuel from nacelle tank via vacuum/suction
- Obtained by: Move crossfeed to CLOSED (removes crossfeed boost; relies on engine-driven pump suction)
- Limitation: Max 10 hours cumulative between engine-driven pump overhauls
- With Avgas (aviation gasoline): Suction feed limited to 8,000 ft altitude; 10 hours max
⚠️ CAUTION: Operating with FUEL PRESS annunciator on is limited to 10 hours, after which the engine-driven high-pressure pump must be overhauled or replaced. Above 8,000 ft with Avgas, boost or crossfeed REQUIRED.
⛽ FUEL HEATING
🌡️ FUEL HEATING
- Fuel heated by: Oil-to-fuel heat exchanger (engine oil heats fuel)
- Purpose: Prevents ice formation in fuel entering the Fuel Control Unit (FCU)
- Location: Between fuel filter and FCU
- Min oil temp for operation: 55°C recommended for oil-to-fuel heater at takeoff power
⚠️ ANNUNCIATORS — FUEL
L/R FUEL PRESS
Low fuel pressure on indicated side. Boost pump failed or crossfeed needed.
→ Check crossfeed AUTO; check boost pump CB; identify failed pump by momentarily closing crossfeed
NO FUEL XFR L/R
Wing tank empty OR transfer pump failed. Nacelle fuel only remaining.
→ Monitor nacelle fuel quantity; land when nacelle reaches minimum
FUEL CROSSFEED
Crossfeed valve receiving power – in transit or open position.
→ Normal during crossfeed operation; verify correct switch position
07
POWERPLANT
PT6A-21 Engine · Propeller · Start Procedures · Limits · Autofeather
🔢 KEY LIMITS — PT6A-21
550 SHP
Takeoff/Max Continuous (flat rated)
695°C ITT
Max ITT Takeoff & Max Cont
1,090°C
Starting ITT limit (2 sec max)
1,315 ft-lb
Max torque T/O & Max Cont
101.5% N1
Max gas generator speed T/O
2,200 rpm
Max propeller rpm (N2)
660°C ITT
Max ITT at Low Idle (below 70% N1)
51% N1
Min Low Idle (C90A); 58% C90B
80–100 psi
Normal oil pressure (takeoff/cont)
40 psi
Min oil pressure (red line)
−40 to +99°C
Oil temperature operating range
37,500 rpm
Gas generator at 100% N1
🔢 TRANSIENT LIMITS
⚠️ TRANSIENT LIMITS (brief exceedance)
| Parameter | Transient Limit | Note |
|---|---|---|
| ITT | 825°C | Very brief; 2-second rule applies |
| Torque | 1,500 ft-lb | Brief transient only |
| N1 | 102.6% | 38,500 rpm |
| Prop RPM (N2) | 2,420 rpm |
🔩 ENGINE DESCRIPTION
🔩 PT6A-21 REVERSE-FLOW FREE-TURBINE DESIGN
The PT6A-21 is a free-turbine, reverse-flow turboprop driving the propeller through planetary reduction gearing (15:1 ratio).
- "Reverse-flow": Air enters at the AFT end of the engine, flows FORWARD through combustor and turbines, exhausts at the FRONT
- "Free-turbine": Two turbine sections on SEPARATE shafts rotating in opposite directions – no physical connection
- Compressor turbine (N1 shaft): Drives compressor and accessories
- Power turbine (N2/NF shaft): Drives propeller through reduction gearbox
Air intake (aft)
→
Axial compressor (3 stage + centrifugal)
→
Combustor (annular)
→
Compressor turbine (N1)
→
Power turbine (NF)
→
Gearbox 15:1 → Propeller
→
Exhaust (forward ports)
📊 COMPRESSOR
- Stages: Three axial + one centrifugal (integral unit)
- Compression ratio: 7.0:1
- Bleed valve: Compressor bleed valve relieves compressor stall
- Stator vanes: Between each stage – diffuse air, raise static pressure
- Combustion air split: 25% for combustion, 75% for flame centering and cooling
- Combustion chamber: Annular type
📊 ENGINE STATIONS
| Station | Location |
|---|---|
| P3 | Compressor outlet – bleed air source |
| T5 / ITT | Interstage turbine temperature (between compressor and power turbines) |
| N1 / NG | Gas generator speed (compressor + compressor turbine shaft) |
| N2 / NP | Propeller RPM (power turbine to propeller) |
| NF | Power turbine RPM (not indicated in cockpit) |
🎛️ ENGINE CONTROLS
🎛️ POWER LEVERS
- Control N1 governor in FCU
- Three ranges: Flight (IDLE to MAX), Beta, Reverse
- Lifted over IDLE detent → Beta/Reverse
- C90B has gated GROUND FINE position
🎛️ PROPELLER LEVERS
- Govern range: 1,800–2,200 rpm
- Takeoff: 2,200 rpm
- Climb: 2,000 rpm (normal)
- Cruise: 1,900 rpm
- Pull past red/white striped detent → FEATHER
🎛️ CONDITION LEVERS
- Positions: FUEL CUTOFF → LO IDLE → HI IDLE
- LO IDLE: Minimum N1 = 51% (C90A) / 58% (C90B)
- HI IDLE: Minimum N1 ≈ 70%
- Variable from LO to HI IDLE (continuous)
- Opens/closes fuel cutoff valve
🚀 ENGINE START SEQUENCE
🚀 GROUND START PROCEDURE — C90A/B/GT
| N1 % | Action / Event |
|---|---|
| 0% | Starter switch to IGNITION AND ENGINE START |
| 12%+ stable | IGNITION ON annunciator illuminates (confirms ignition active) |
| 12%+ stable | Move condition lever to LO IDLE (opens fuel cutoff valve) |
| Fuel on | Monitor ITT closely — limit 1,090°C (2 sec max) on start |
| Rising | Monitor oil pressure – should rise quickly to min 40 psi |
| Stabilized ~51% | Release starter; confirm N1 stable, ITT normal |
| Stable | Generator switch to ON; confirm loadmeter reading |
⚠️ HOT START: If ITT approaches 1,090°C dashed red line during start – move condition lever to FUEL CUTOFF immediately. Do NOT wait for the needle to cross the limit.
🌡️ OIL SYSTEM
🌡️ OIL PRESSURE & TEMPERATURE
| Oil Press | Status |
|---|---|
| 80–100 psi | Normal (green arc) |
| 40–80 psi | Undesirable – complete flight, reduced power |
| < 40 psi | UNSAFE – shut down or land immediately, min power |
| > 100 psi | Max; 200 psi may occur in cold starts (transient) |
| Oil Temp | Status |
|---|---|
| 74–80°C | Recommended for service life |
| 55°C min | For oil-to-fuel heater at takeoff power |
| -40 to +99°C | Operating range |
| 0.2 lb/hr max | Maximum average oil consumption |
🔄 PROPELLER SYSTEM
🔄 GOVERNORS
- Primary governor: Maintains selected rpm 1,800–2,200; oil pressure mechanism through flyweights and pilot valve
- Governor pump: Raises oil to ~375 psi for blade pitch control; driven by N2 shaft
- Oil pressure effect: More oil pressure = LOWER pitch (fine); feathering springs drive to HIGH pitch (feather)
- Overspeed governor: Limits propeller to 2,288 rpm if primary governor fails
- Fuel topping governor: Limits rpm by reducing engine power if >6% above selected rpm
🔄 FEATHERING
- Manual feather: Pull propeller lever past red/white detent into striped range
- Auto feather on shutdown: Loss of oil pressure → feathering springs and counterweights drive blades to feather
- Unfeather: Push propeller lever forward into governing range
- C90A blade angles: Feather +87°, Primary low +15°, Max reverse -11°
- C90B blade angles: Feather +85.8°, Ground fine +3°, Max reverse -10°
🔄 SYNCHROPHASER (PHASE SYNCHRONIZER)
🔄 SYNCHROPHASER — TODOS OS MODELOS
- Function: Automatically matches both propeller RPMs AND keeps the blades at a predetermined phase position — reduces propeller beat and cabin noise
- Type II: Certified for takeoff and landing. NOT a master-slave system. No annunciator light.
- Para ativar (C90A/B): Manually synchronize within a maximum difference of 20 rpm, depois ligar a chave
- Para mudar RPM com synchrophaser LIGADO: Ajustar ambas both propeller levers at the same time
- Autoridade limitada: Does not reduce RPM below the propeller lever selection — safe with a feathered propeller
- Synchroscope: Disco preto e branco no painel. Parado = sincronizado
🛡️ AUTOFEATHER SYSTEM
🛡️ AUTOFEATHER SYSTEM
- ARM condition: AUTOFEATHER switch armed AND power levers above 90% N1
- AUTOFTHR ARMED advisory: System armed and ready
- Trigger: Torque drops below 400 ft-lb on armed engine
- AUTO IGN advisory: Torque below 400 ft-lb – ignition armed
- After lift-off if autofeather initiates: Continue to fly the airplane and allow the propeller to feather – do NOT interfere immediately
- Armed for: Takeoff only – disarm after reaching safe altitude/speed
- Test switch: AUTOFEATHER TEST position tests system on ground
AUTOFEATHER — WHAT TRIGGERS IT
AArmed – switch armed AND power levers >90% N1
TTorque drops below 400 ft-lb on that engine
FFeather – propeller automatically feathers
RReaction – fly the airplane, let it happen
⚠️ ANNUNCIATORS — POWERPLANT
CHIP DETECT L/R
Metal contamination in engine oil. Red on C90A (emergency); amber on C90B (monitor).
→ C90B: Check engine instruments; if normal, no action required – land and inspect. C90A: Monitor closely per checklist
L/R AUTO IGN
Ignition armed and active. Torque below 400 ft-lb OR start switch in ignition position.
L/R AUTOFTHR ARMED
Autofeather system armed with power levers above 90% N1. Ready to feather if torque fails.
⚠️ ITT RESTRICTION AT IDLE
⚠️ ITT RESTRICTION AT IDLE (C90A/B): With N1 below 70%, maximum ITT is 660°C.
1. Reduzir carga do gerador
2. Avançar condition lever para HI IDLE
3. Desligar ar condicionado temporariamente
1. Reduzir carga do gerador
2. Avançar condition lever para HI IDLE
3. Desligar ar condicionado temporariamente
08
FIRE PROTECTION
Detection · Photoconductive Cells · Fire Extinguishing · Testing
🔥 FIRE DETECTION SYSTEM
🔥 DETECTION COMPONENTS
- Type: Photoconductive cell (infrared) flame detectors — NOT thermal loop type
- Quantity: Three photoconductive cells per engine compartment (6 total)
- Control amplifier: One per engine; relays close at preset alarm level
- Warning lights: L ENG FIRE and R ENG FIRE (red) on annunciator panel
- Test switch: Copilot's left subpanel – placarded TEST SWITCH–FIRE DET
- Test positions: OFF – 3 – 2 – 1 (test each of 3 detectors per engine)
- Power: Operable whenever generator buses are active
🔍 HOW IT WORKS
Conductivity through each photocell varies with infrared radiation intensity. As conductivity increases, current increases. When signal reaches preset alarm level, the control amplifier relay closes → triggers annunciator. When fire extinguishes, signal drops → relay opens automatically. No manual reset needed.
🧯 FIRE EXTINGUISHING SYSTEM (Optional)
🧯 EXTINGUISHING SYSTEM
- Type: Explosive cartridge inside extinguisher of each engine
- Capacity: ONE shot per engine between rechargings – cannot be crossfed
- Power: Hot battery bus – can be fired even with engines off, generators off
- Switches: Below glareshield annunciator panel (C90A) / each side of panel (C90B)
- To discharge: Raise break-away clear plastic cover → press face of lens
| Lens Color | Meaning |
|---|---|
| RED (L/R ENG FIRE EXT PUSH) | Fire detected in engine – push to discharge |
| AMBER (D) | System discharged – supply cylinder empty (latches ON regardless of battery) |
| GREEN (OK) | Preflight test only – system serviceable |
🧪 TESTING
🧪 FIRE DETECTION TEST PROCEDURE
- Rotate TEST SWITCH through each of the 3 test positions (1, 2, 3)
- Each position should illuminate: FAULT WARNING flasher, L ENG FIRE, R ENG FIRE annunciators
- If optional fire extinguishing installed: Also L ENG FIRE EXT PUSH and R ENG FIRE EXT PUSH red lenses
- Failure to illuminate in any position: Malfunction in that detector circuit
- Test anytime – ground or flight
⚠️ ANNUNCIATORS — FIRE
L/R ENG FIRE
Fire detected in left or right engine compartment by photoconductive cell detectors. Immediate pilot reaction required.
→ EMERGENCY: Execute ENGINE FIRE checklist. Condition lever cutoff, firewall valve closed, extinguisher if installed
09
PNEUMATICS
Bleed Air · Vacuum System · Surface Deice · Rudder Boost · Door Seals
🔢 KEY VALUES
18 psi
Regulated bleed air pressure
21 psi
Relief valve setpoint (regulator fail)
4 psi
Door/hatch seal pressure
5.9 in Hg
Normal vacuum (one engine, 70-80% N1)
450°F
Bleed air temp at P3 tap
90–120 psi
Max bleed air pressure (pre-regulated)
⚙️ BLEED AIR SYSTEM
⚙️ PNEUMATIC SYSTEM OVERVIEW
High-pressure bleed air from each engine compressor P3 tap supplies multiple systems:
Engine P3 tap (90-120 psi, ~450°F)
→
18 psi regulator (under right seat deck)
→
Common manifold
18 psi manifold
→
Surface deice boots
18 psi manifold
→
Rudder boost system (13 psi servo)
18 psi manifold
→
Vacuum ejector → Gyro vacuum + pressurization control
18 psi manifold
→
4 psi regulator → Door/escape hatch seals
💡 Check valve: In each bleed air line from each engine. Prevents backflow through inoperative engine side during single-engine ops. One engine can supply ALL systems.
🌀 VACUUM SYSTEM
- Source: Bleed-air ejector (venturi effect creates suction)
- Range: 15 in Hg at sea level to 6 in Hg at 31,000 ft
- Normal reading (1 eng, 70-80% N1): 5.9 +0/-0.2 in Hg
- Gyro suction gage: Copilot's right subpanel (in Hg)
- Vacuum regulator: Nose compartment, left side of pressure bulkhead
- Powers: Air-driven gyros, pressurization controller/outflow valve
🚪 DOOR SEALS
- Airstair door seal: 4 psi pneumatic inflation
- Emergency exit hatch seal: 4 psi pneumatic inflation
- Valve type: Normally CLOSED electric solenoid valve (opens to allow seal inflation in flight)
- Squat switch: Left squat switch – closed on ground (prevents seal inflation on ground)
- 4 psi pressure regulator: Downstream from 18 psi manifold
📊 GAGES
📊 PNEUMATIC PRESSURE GAGE
- Located: Copilot's right subpanel
- Reads: PSI available in pneumatic system
- Normal: ~18 psi at 70-80% N1
- Low pressure: Check engine N1, bleed air availability
📊 GYRO SUCTION GAGE
- Located: Copilot's right subpanel (to left of pneumatic pressure gage)
- Reads: Inches Hg (vacuum)
- Normal: ~5.9 in Hg (one engine)
- Low: Gyro instruments may become unreliable
10
ICE AND RAIN PROTECTION
Engine Anti-ice · Wing Deice · Pitot Heat · Windshield Heat · Prop Deice
🔢 KEY VALUES
5°C / 41°F
OAT threshold for ice vanes
120 KIAS
Min speed in sustained icing
7–8
Pilot-controlled anti-ice/deice systems
30 sec
Propeller deice cycle per blade
✈️ ANTI-ICE/DEICE SYSTEMS OVERVIEW
✈️ ALL SYSTEMS OVERVIEW
| System | Type | Medium | Controls |
|---|---|---|---|
| Engine inlet (ice vanes) | Anti-ice | Bleed air (mechanical) | L/R ANTI-ICE switches |
| Pitot masts (2) | Anti-ice | Electric heating elements | PITOT HEAT switch |
| Windshield | Anti-ice | Electric heating elements | WINDSHIELD switch NORM/HI |
| Wing/tail deice boots | Deice (inflatable) | Pneumatic bleed air | SURFACE DEICE switch |
| Propeller deice | Deice | Electric heating elements | PROP DEICE switch |
| Stall warning vane heat | Anti-ice | Electric | Part of stall warning system |
| Fuel vent heat | Anti-ice | Electric | Auto (tied to boost pump) |
🌀 ENGINE INLET ANTI-ICE (ICE VANES)
🌀 ENGINE ICE VANES
- Type: Inertial separator vanes – mechanically deflect large ice particles out of airflow
- When to extend: Anytime OAT is below 5°C AND flight free of visible moisture cannot be assured
- ICE VANE advisory (green): Vanes are in icing position (extended) – normal indication when extended
- ICE VANE caution (amber): Vanes in transit or inoperative
- Switches: L/R MAIN ANTI-ICE and STANDBY ANTI-ICE
- Standby: Backup system if main fails; opposite side wiring for redundancy
💡 Note: Engine ice vanes are mechanical (not thermal/bleed air). They provide inertial separation of ice particles – different from heating systems.
❄️ SURFACE DEICE BOOTS
- Surfaces protected: Leading edges of wings, vertical and horizontal stabilizers
- NOT protected: Propeller blades, spinner, upper wing surfaces, radome
- Type: Inflatable pneumatic boots (bleed air)
- Power: Center Bus (SURFACE DEICE switch)
- Operated: After ice accumulates on leading edges (not preventive)
- Deflation: Also uses pneumatic system (vacuum)
🔌 PROPELLER DEICE
- Type: Electric heating elements embedded in each blade
- System: Automatic cycling – heats each blade for 30 seconds
- Power: Center Bus (prop deice power and control)
- Night icing: At least one ice light must be operational
- Required lights (night icing): All ice lights installed must be operational
💧 WINDSHIELD HEAT
- Type: Electric heating elements in windshield
- Positions: NORMAL or HI
- Side effect: May cause erratic operation of magnetic flux detectors (compass) when on NORMAL or HI
- Wipers: Only when there is water on windshield; not for dry use
- Wiper switch: Center Bus
🌡️ PITOT HEAT
- Type: Electric heating elements in pitot masts
- When to turn on: Just prior to takeoff (not on ground for extended time – risk of burn damage)
- Two pitot masts: Pilot and copilot sides
- Stall warning vane: Also has heat – powered from R Gen Bus (stall warning heat)
⚠️ STALL WARNING IN ICING
⚠️ STALL WARNING VANE UNRELIABLE: If there is an accumulation of ice on the leading edge of the wing, the stall warning vane is NOT to be considered reliable. The stall warning vane circuit breaker will also open. Minimum speed in sustained icing: 120 KIAS.
⚙️ AUTO-IGNITION SYSTEM
⚙️ AUTO-IGNITION (ENGINE)
- AUTO-IGNITION switch: ARM or OFF
- When ARMED: Ignition is INACTIVE but armed when torque is greater than 400 ft-lb
- Activates automatically: When torque drops below 400 ft-lb (flameout protection)
- When to activate: Just prior to takeoff; also before flight in rain (per POH)
- AUTO IGN advisory: Illuminates when system is armed AND torque drops below 400 ft-lb, OR ignition/engine start switch ON
💡 Memory Aid: AUTO-IGNITION armed = ignition is INACTIVE above 400 ft-lb, ACTIVE below 400 ft-lb. It is NOT continuous ignition when armed above 400 ft-lb.
11
AIR CONDITIONING
Bleed Air Heat · Refrigeration · Cabin Controls · Electric Heat
⚙️ SYSTEM OVERVIEW
⚙️ AIR CONDITIONING OVERVIEW
The system provides heating, cooling, and fresh air ventilation using a combination of engine bleed air, refrigeration, and electric heating.
Engine bleed air (P3)
→
Air-to-air heat exchangers (cools bleed air)
→
Flow control unit
→
Mixing plenum → cabin distribution
RAM air (ambient)
→
Refrigeration (vapor cycle)
→
Cool air → mixing plenum
🌡️ BLEED AIR HEATING
- Bleed air bypass valves: Control proportion of hot bleed air vs cooled air to cabin
- MANUAL TEMP INCR/DECR switch: Hold to DECR for 60 seconds to fully close both bypass valves
- Pneumatic thermostat: Automatic temperature control of bleed air mixing
- Bleed-air shutoff valve: On each firewall – separate from fuel firewall shutoff
- Bleed-air bypass valve: In wheel well area – routes air around heat exchanger
❄️ REFRIGERATION SYSTEM
- Type: Vapor cycle refrigeration (compressor, evaporator, condenser)
- Compressor: Electrically driven; Center Bus
- Condenser: In wheel well area (cooled by ram air)
- Receiver-dryer: In wheel well
- Ambient shutoff valve: Closes when refrigeration is used (pressurized flight)
🔌 ELECTRIC HEAT SYSTEM
🔌 ELECTRIC HEAT
- Heating elements: 6 total in the system; 4 used in flight, 2 additional for ground only
- NORMAL HEAT: Center Bus (normal heating load)
- MAX HEAT: Center Bus (all elements)
- Ground-only elements: Additional heating elements only for ground preheating
💨 DISTRIBUTION CONTROLS
💨 AIR DISTRIBUTION
| Control | Function |
|---|---|
| PILOT AIR (pull on) | Controls air to floor outlets at pilot position |
| COPILOT AIR (pull on) | Controls air to floor outlets at copilot position |
| CABIN AIR (pull on) | Controls cabin air discharge rate from bleed-air duct system |
| DEFROST AIR (pull on) | Directs air to glareshield eyeball outlets and defroster |
| VENT BLOWER switch (LO/HI) | Controls ventilation blower speed |
ℹ️ Eyeball outlets (glareshield): Airstream adjusted by twisting the nozzle. The DEFROST AIR control knob regulates the air discharge rate from glareshield eyeball outlets.
🌬️ FRESH AIR VENTILATION
🌬️ UNPRESSURIZED FLIGHT VENTILATION
- Source during unpressurized flight: RAM air through a fresh air scoop (ambient air)
- Ambient shutoff valve: Allows ram air entry during unpressurized ops
- Pressurized flight: Bleed air only (ambient valve closed)
12
PRESSURIZATION
Pressure Vessel · Outflow Valve · Controller · Cabin Altitude · Safety Valve
🔢 KEY VALUES
>5.0 psi
Max design pressure differential
0.1 psi
Max negative differential allowed
10,000 ft
ALTITUDE WARN trigger (12,500 LJ-1353+)
14 lbs/min
Approx bleed air flow into cabin
-1,000 ft
Min cabin altitude setting
+10,000 ft
Max cabin altitude setting
🏗️ PRESSURE VESSEL
🏗️ PRESSURE VESSEL DESCRIPTION
- Forward bulkhead: Between cockpit and nose section
- Rear bulkhead: Just aft of cabin baggage compartment
- Windows: Round (maximum strength for pressurization loads)
- Volume: 313.6 cubic feet
- Outflow valve: On aft pressure bulkhead – controls cabin pressure
- Safety/dump valve: Also on aft pressure bulkhead – adjacent to outflow valve; silencer installed
⚙️ PRESSURIZATION CONTROLLER
⚙️ PRESSURIZATION CONTROLLER OPERATION
Located on the pedestal. Commands modulation of the outflow valve via pneumatic pressure.
- CABIN ALT scale (outer): Set desired cabin altitude
- ACFT ALT scale (inner): Maximum aircraft altitude at which cabin stays at selected altitude
- RATE control (MIN–MAX): Controls rate of cabin altitude change (200–2,000 fpm approximately); most comfortable between 9-12 o'clock positions
- Cabin altimeter: Shows actual cabin pressure altitude and differential (right side, above pedestal)
- Cabin climb indicator: Shows rate of cabin pressure altitude change (to left of cabin altimeter)
- Setting for descent: Set cabin altitude ~500 ft above landing field altitude
🔀 CABIN PRESSURE SWITCH
🔀 CABIN PRESS SWITCH (DUMP/PRESS/TEST)
| Position | Effect |
|---|---|
| DUMP (forward, locked) | Safety valve HELD OPEN – cabin depressurizes and stays unpressurized |
| PRESS (center) | Normal – outflow valve controlled by pressurization controller; safety valve normally closed |
| TEST (aft, spring-loaded) | Safety valve HELD CLOSED (bypasses landing gear safety switch) for ground testing |
🔒 SAFETY VALVE
🔒 SAFETY/DUMP VALVE FUNCTIONS
- Function 1: Pressure relief if outflow valve malfunctions (prevents over-pressurization)
- Function 2: Depressurizes cabin when CABIN PRESS switch moved to DUMP
- Function 3: Negative pressure relief – prevents cabin from going 0.1 psi below ambient (rapid descent protection)
- Silencer: Installed on safety and dump valves for quiet operation
📋 PRESSURIZATION SEQUENCE
📋 TAKEOFF PRESSURIZATION SEQUENCE
On ground
→
Safety valve open, ambient valve closed – NOT pressurized
Liftoff
→
Safety valve closes; Left flow control ambient solenoid opens (~0 sec)
~6 sec after
→
Right flow control ambient solenoid opens (staged to avoid pressure bump)
Climb
→
Outflow valve modulates to maintain selected cabin altitude
⚠️ ANNUNCIATORS — PRESSURIZATION
ALTITUDE WARN
Cabin altitude exceeds 10,000 ft (12,500 ft on LJ-1353+). Supplemental oxygen required per FARs.
→ Don oxygen if available; initiate emergency descent; check pressurization system
14
LANDING GEAR AND BRAKES
Hydraulic System · Gear Operation · Brakes · Emergency Extension
🔢 KEY SPEEDS & VALUES
182 KIAS
VLO — Gear extension/extended speed
163 KIAS
VLO — Gear retraction speed
184 KIAS
VFE — Approach flaps (not gear)
~62% N1
Gear warning horn activation
60 A
Hydraulic motor circuit breaker
⚙️ SYSTEM DESCRIPTION
⚙️ LANDING GEAR SYSTEM
- Type: Electrically controlled, hydraulically actuated retractable tricycle gear
- Shock struts: Beech air/oil type – filled with compressed air AND hydraulic fluid
- Drag legs: Folding braces – rigid when gear extended (provide downlock)
- Downlocks: Internal mechanical downlocks within actuators (hold gear extended)
- Uplocks: Hydraulic pressure holds gear UP
- Main gear doors: Mechanically actuated by cam/torque tube; hinged at sides
- Nose gear doors: Spring-loaded open; cam draws closed during retraction
🔌 HYDRAULIC SYSTEM
💧 HYDRAULIC POWER PACK
- Power pack location: Left center wing section
- Hydraulic reservoir: Left center wing section (dipstick for fluid level check)
- Motor type: Electrically driven hydraulic pump
- Selector valve: Electrically actuated; directs fluid to individual gear actuators
- Power for motor: 60A circuit breaker; landing gear motor control circuit from center bus
- Pump operation after retraction: STOPS when gear fully up; cycles as needed to maintain pressure
- HYD FLUID caution: Low hydraulic fluid in reservoir
🔒 SAFETY FEATURES
🔒 INADVERTENT RETRACTION PREVENTION
- Safety switches: On main landing gear – prevent handle from moving to UP when on ground (weight on wheels)
- Handle guard: Must lift handle guard to retract gear
- Ground prevents UP: Weight of aircraft on main gear activates safety switches
🔔 GEAR WARNING HORN
- Trigger: One or both power levers retarded to approximately 62% N1 with gear not down/locked
- Flap trigger: Flaps below APPROACH position also can trigger
- Silence button: Allows silencing horn (caution – gear may not be down)
- Green gear lights: One per gear leg – indicates gear down and locked
- Red handle lights: Gear in transit or unsafe
🅿️ GEAR POSITION INDICATORS
🅿️ LANDING GEAR INDICATIONS
| Indication | Meaning |
|---|---|
| 3 green lights (down) | All 3 gears down and locked — safe to land |
| No lights (gear up, power on) | Gear retracted normally |
| Red handle lights | Gear in transit or unsafe condition |
| In-transit light relay | Activated during gear travel |
🚨 EMERGENCY GEAR EXTENSION
🚨 EMERGENCY EXTENSION
- Gear can be extended by alternate/emergency means if hydraulic pump fails
- Procedure includes hand pump or gravity extension per POH
- Verify 3 green lights after any emergency extension
- With hydraulic failure: Do not cycle gear – land as soon as practical
- Brake reservoir: Located in left center wing section beside landing gear power pack
🛞 STEERING & BRAKES
🛞 NOSEWHEEL STEERING
- System: Direct cable/linkage from rudder pedals to nosewheel
- Spring-loaded link: Absorbs initial force; more pedal = more deflection once rolling
- Gear retracted: Spring absorbs force; no nosewheel movement but rudder still deflects
- Nosewheel self-centering: Centers automatically upon retraction
- Enhanced turning: Combine rudder pedal + differential braking for tighter turns
- Towing: MUST remove rudder lock before towing (to protect steering linkage)
🛑 BRAKES
- Parking brake: Pull aft THEN depress brake pedal (not depress then pull)
- Correct sequence: Pull parking brake control AFT → then depress brake pedal to build pressure
- Parking brake limitation: NOT to be used as chock when airplane left unattended
- Differential braking: CAN be used for ground maneuvering (it's appropriate/normal)
- Brake reservoir: Left center wing section, next to landing gear power pack
⚠️ ANNUNCIATORS — LANDING GEAR
HYD FLUID
Hydraulic fluid reservoir level is low. Landing gear system may be compromised.
→ Minimize gear cycling; plan for possible emergency extension; land as soon as practical
PROP GOV
Propeller levers not in high RPM position with landing gear extended. Reminder for go-around configuration.
15
FLIGHT CONTROLS
Flaps · Trim · Rudder Boost · Yaw Damper
🔢 KEY VALUES
25,000 ft
Max altitude with yaw damper inop
3 positions
Flap positions: UP / APPROACH / DOWN
184 KIAS
VFE — Approach flaps
148 KIAS
VFE — Down (full) flaps
🛩️ FLAP SYSTEM
🛩️ FLAP SYSTEM — C90A
- Type: Four-segment Fowler-type flap system
- Positions: UP, APPROACH (partial), DOWN (full)
- C90A selector: Three-position toggle switch
- Power: Left Generator Bus (flap motor and control)
- Limitation: VFE Approach = 184 KIAS; VFE Down = 148 KIAS
🛩️ FLAP SYSTEM — C90B
- Type: Super King Air 350 follow-up type selector
- Positions: UP, APPROACH, DOWN (flaps follow selector position)
- Moving DOWN to APPROACH: Flaps retract to APPROACH position (will NOT bypass)
- Same VFE limits apply
⚖️ TRIM SYSTEM
⚖️ ELECTRIC PITCH TRIM
- Initiated by: Either the pilot OR copilot moving BOTH elements of their PITCH TRIM switch simultaneously (split-switch design for safety)
- NOT initiated by: Moving only one element of the switch
- Disconnect switch: On each control wheel – PITCH TRIM DISC caution if disconnected with power switch ON
- Aileron trim: Manually operated trim tab on right aileron
- Rudder trim: Manual trim tab on rudder
- Elevator trim tabs: Two tabs on elevator
💡 Key Distinction: Electric pitch trim requires BOTH elements of EITHER pilot's OR copilot's switch – not split between both pilots. This prevents inadvertent trim commands.
🔄 RUDDER BOOST SYSTEM
🔄 RUDDER BOOST
- Purpose: Reduces pilot rudder pedal effort during single-engine flight
- Power source: Pneumatic bleed air (servo valve system)
- Power (electrical): R Gen Bus (rudder boost circuit)
- Test during runup: Increase power on one engine until the rudder on the OPPOSITE side moves forward
- Automatic: Activates when yaw/asymmetric thrust detected; adds rudder force in correct direction
🎯 YAW DAMPER
🎯 YAW DAMPER LIMITATION
⚠️ LIMITATION: Maximum altitude with yaw damper inoperative: 25,000 feet. Above this altitude, Dutch roll characteristics require yaw damper for safe operation.
16
AVIONICS
HSI · Flight Director · NAV/COMM · Audio · Pitot-Static · Alternate Static
🖥️ AVIONICS MASTER
🖥️ AVIONICS MASTER SWITCH
- Location: Isolation panel (center of instrument panel)
- If Avionics Master fails: Pull the Avionics Master CIRCUIT BREAKER to restore avionics power
- Avionics buses: Nº 1 = Triple-Fed Bus (opera na bateria com dupla falha), Nº 2 = Barr. Ger. Esq., Nº 3 = Barr. Ger. Dir.
📡 NAV/HSI DISPLAY
📡 HSI NEEDLE COLORS
| Source | Status | Color |
|---|---|---|
| GPS | Curso ATIVO | BRANCA |
| VOR ou LOC | Curso ATIVO | VERDE |
| VOR ou LOC | Curso PRÉ-SELECIONADO | CIANO |
| ADF ou GPS (bearing pointer) | Agulha dupla | MAGENTA |
| VOR, ADF, GPS (bearing pointer) | Agulha simples | CIANO |
ℹ️ Para memorizar — CURSO ATIVO: GPS = White · VOR/LOC = Green · Preset = Cyan
BEARING POINTERS: Agulha simples = Ciano · Agulha dupla = Magenta.
BEARING POINTERS: Agulha simples = Ciano · Agulha dupla = Magenta.
🎛️ FLIGHT DIRECTOR
🎛️ FLIGHT DIRECTOR ANNUNCIATIONS
| Mode | Color |
|---|---|
| ACTIVE (lateral + vertical) | GREEN |
| ARMED (waiting to capture) | WHITE |
📻 RADIO MEMORY FREQUENCIES
| Radio | Memory Channels |
|---|---|
| NAV radios | 6 memory frequencies each |
| COMM radios | 8 memory frequencies each |
🎧 AUDIO SYSTEM
🎧 AUDIO PANEL
- VOICE/BOTH/RANGE switch: Selecting RANGE — pilot hears ONLY Morse code identification of NAV source
- Individual audio switches: Across top of panel – control audio to speakers/headphones for pilot and copilot separately
- EMER position on AUDIO switch: Restores communication if normal audio fails
- NORM position: Standard operation
⚠️ EHSI WARNING FLAGS
⚠️ EHSI FLAGS
| Flag | Meaning | Behavior |
|---|---|---|
| HDG | Falha no sistema de rumo | Flashes 10 sec before becoming steady |
| GS | Falha no glide slope | Substitui a escala de desvio vertical |
| DPU FAIL | Falha no Display Processor Unit | Steady |
| B/C | Back-course LOC ativo (proa >105° do curso) | CDI invertido automaticamente |
| ---- | Invalid DME data | Mesma cor do curso ativo |
All flags (except distance/data) are red. HDG, DSP and bearing pointer flags flash for 10 sec before becoming steady.
🔋 EFIS AUX POWER
🔋 SISTEMA EFIS AUX POWER
- Function: Standby source — prevents pilot displays from blanking during momentary voltage drops
- Limitation: For short-duration use only — does not replace the normal source in a prolonged failure
- Refer to the POH for test and operating procedures
🧭 SLAVED COMPASS
🧭 SLAVED COMPASS — COLLINS MCS-65
- C90B/GT padrão: Collins MCS-65 (dois sistemas)
- Alternativas opcionais: King KCS-55A, Sperry C-14A-43, Collins MCS-103 — operam de forma similar
- Windshield heat NORMAL/HI may cause erratic flux valve sensor operation
📊 SISTEMA PITOT-ESTÁTICO DUPLO
📊 DUAL PITOT-STATIC SYSTEM
- Two independent systems: Pilot side and copilot side pitot-static
- Pitot masts: Two heated pitot masts – L Gen Bus and R Gen Bus powered
- Static ports: On both sides of fuselage
- Alternate static air: Switch on pilot's side panel
- Alternate static source location: Inside the unpressurized area of the empennage (tail section)
- Alternate static — airspeed/altimeter errors: Expect slight errors when using alternate static; refer to airspeed correction table in POH
💡 Alternate Static Air: When selected, pitot-static instruments receive air from INSIDE the unpressurized tail area — NOT the upper or lower static ports on the fuselage side.
⚠️ ANNUNCIATORS — AVIONICS
INV FAIL
Inverter (AC power for avionics) has failed. Select alternate inverter or operate on DC-only avionics.
→ Select alternate inverter from INVERTER switch on pilot's subpanel
17
MISCELLANEOUS SYSTEMS (OXYGEN)
Crew Oxygen · Passenger Masks · FAR Requirements · Duration
🫁 OXYGEN SYSTEM
🫁 CREW MASKS — DILUTER DEMAND
- Type: Diluter-demand, quick-donning crew masks
- Set to NORMAL: At altitudes BELOW 20,000 ft (dilutes oxygen with cabin air)
- Set to 100%: At altitudes ABOVE 20,000 ft (pure oxygen)
- Quick-donning: Can be put on with one hand; meets 5-second donning requirement
- If smoke in cockpit: Use 100% regardless of altitude
💺 PASSENGER OXYGEN
- Automatic deployment: Automatically when cabin altitude exceeds 12,500 ft
- Manual deployment: Pilot pulls PASSENGER MANUAL DROPOUT handle
- Type: Chemical oxygen generators (continuous flow)
- Not manually deployed by passengers: System is crew/auto controlled
- Oxygen bottle: Located in aft fuselage
📊 DURATION CALCULATION
📊 100% OXYGEN SETTING — DURATION CALCULATION
When crew masks are selected to 100%, the number of crew masks used for computing oxygen duration is DOUBLED (each mask uses twice as much oxygen at 100% vs. diluted).
💡 Example: 2 crew members on 100% = count as 4 people when using the oxygen duration chart. This accounts for higher flow rate at 100% oxygen.
📋 FAR OXYGEN REQUIREMENTS
📋 FAR REQUIREMENTS (GENERAL REFERENCE)
| Condition | Requirement |
|---|---|
| 12,500–14,000 ft cabin alt (over 30 min) | Crew must use oxygen |
| Above 14,000 ft cabin alt | Crew must use oxygen at ALL times |
| Above 15,000 ft cabin alt | Each passenger must be provided oxygen |
| Pressure altitude above 25,000 ft | Quick-donning crew masks required |
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