MD-80 Series System Description & Limitations

Vocabulary practice flashcards covering systems description, operational limitations, engine and APU limits, anti-ice procedures, and memory items for the MD-80 series.

TCAS Scan Modes

Scan ranges for TCAS traffic monitoring: ABV scans $9900\,ft$ above to $2700\,ft$ below; NORM scans $2700\,ft$ above to $2700\,ft$ below; BLW scans $2700\,ft$ above to $9900\,ft$ below.

Hydraulic System Operating Pressures

System pressure ranges: Normal system pressure is $2800\text{--}3000\,psi$; upon electrical loss, the pump reverts to $3000\,psi$; relief valve activates when pressure exceeds $3600\,psi$; HYD PRESS LOW annunciates below $900\,psi$ and turns off above $1200\,psi$.

Hydraulic Consumers (Left vs. Right System)

Left Hydraulic System powers L thrust reverse, inboard flight spoilers, outboard flap cylinder, and elevator augmentation. Right Hydraulic System powers R thrust reverse, outboard flight spoilers, inboard flap cylinder, rudder, landing gear, and aft stairway. Dual consumers powered by both include slats, flaps, ground spoilers, nose wheel steering, and brakes.

Ground Shift Mechanism Error

Occurs when the nosewheel can be turned. The gears must NOT be attempted to be retracted, as serious damage can be left on the aircraft.

APU Starter Motor Duty Limits

Duty cycles for the APU starter motor: $2 \times 90\,sec$ with $5\,min$ cooling, or $90\,sec$ start with $60\,min$ cooling. Temperature must be $<100^\circ\text{C}$ before a second attempt can be initiated.

Automatic Reserve Thrust (ART)

Thrust backup system that disarms below $49\%$ $N_1$ or upon slat retraction and arms when $N_1 \ge 64\%$. Activates when a $>30\%$ $N_1$ difference signal is received from DFGC, power to DFGC is lost, or 1-2 DFGS switch is moved. Provides $+850\,lb$ to JT8D-217C and $+700\,lb$ to JT8D-219.

Automatic Thrust Restoration (ATR)

System engaged with autothrottle that arms when pitch mode is in takeoff, aircraft altitude is $>350\,ft$, and both engines cut back $>0.1\,EPR$. Activates when $N_1\Delta > 7\%$ and $EPR\Delta > 0.25$, or vertical speed $V/S \le 0$ for more than $5\,sec$.

Engine Starter Limits

Operating limitations for engine starter engagement: $2 \times 90\,sec$ ON, $5\,min$ OFF, $30\,sec$ ON, $5\,min$ OFF.

Inoperative Pressurization Operating Limit

Maximum flight level permitted when one pressurization system is inoperative is FL 250.

Engine Anti-Ice Normal Operations

Conditions and indications for engine anti-ice operation: VALVE OPEN annunciation, ENG ANTI ICE light ON, IGN switch set to GRND START & CONT, operated ON between $-15^\circ\text{C}$ and $+6^\circ\text{C}$, and turned ON only one at a time.

Airfoil Anti-Ice Normal Operations

Conditions and indications for airfoil anti-ice operation: X-feed pneumatic lever open, Anti ice switch ON, ANTI ICE WING light ON, and turned ON when OAT $<+6^\circ\text{C}$.

Tail De-Ice Normal Operations

Operating parameters for tail de-ice: used at $20\,min$ intervals, activated $1\,min$ prior to flap selection, with cycle durations of $2.5\,min$ ($150\,sec$).

EFIS Display Modes (ADF AWF RAMP)

Easy memory mnemonic for EFIS modes: ADF modes are Rose and Arc; Weather (Wx) modes are Arc and Map; FMS modes are Map and Plan.

Parallel Rudder vs. Series Rudder

Parallel Rudder is driven by A/P rudder servo drive, moving pedals up to MAX $17^\circ$, active in Takeoff, Land & Go around modes (or LOC/GS TRACK below $1500\,ft$ RH with flap $>26^\circ$). Series Rudder is driven by A/P yaw actuator with no pedal movement up to MAX $2.5^\circ$, active only in climb, cruise, and descent.

VOR Tracking Engagement Mode Rules

VOR TRK engages if within \pm 2 dots. If a new VOR is not set after entering the cone of confusion within $3\,min$, basic HDG HLD mode will engage.

FMS Guidance Commands

System commands issued by FMS: FMS RNAV gives A/T THRUST command and A/P F/D PITCH command; FMS NAV gives A/P F/D ROLL command. VNAV can be activated at $1000\,ft$ AGL with CLB EPR set.

Cross-Tie (X-Tie) Relay Operation

Electrical cross-tie relay rules: engine generators operate on Ground and Flight; APU operates in Flight only; EPU operates Never.

Engine Ignition Override Limits

Time limitations for IGN OVRD setting: $2\,min$ ON, $3\,min$ OFF, followed by $2\,min$ ON, $23\,min$ OFF.

MD-80 Runway Slope Limitations

Maximum runway slope gradients: Takeoff maximum is $+1.7\% / -2.0\%$; Landing maximum is $+2.0\% / -2.0\%$.

Two Engine Flameout Memory Items

Immediate action memory items for two engine flameout: set EMER PWR SWITCH to ON, and set ENG IGN SELECTOR to OVRD.

Runaway Stabilizer Trim Memory Items

Immediate action memory items for runaway stabilizer trim: DISCONNECT AUTOPILOT, and actuate Control Wheel Trim Switches to TRIM OPPOSITE.