Aircraft Limitations Flashcards
What is Vmo or Mmo?
MAXIMUM OPERATING LIMIT;
The SPEEDS that may NOT be DELIBERATELY EXCEEDED in any regime of flight (Climb, cruise or descent)
What is Vfe?
FLAP EXTENDED SPEEDS;
SPEEDS that may NOT be EXCEEDED because of FLAP DESIGN LIMITS
What is Vlo?
LANDING GEAR OPERATING SPEED;
LIMIT for which below it is SAFE to both EXTEND and RETRACT landing GEAR;
If EXTENSION and RETRACTION SPEEDS are different they are designated as Vlo(EXT) and Vlo(RET)
What is Vle?
LANDING GEAR EXTENDED SPEED;
LIMIT for which below it is safe to fly with LANDING GEAR secured in the FULLY EXTENDED POSITION
What is Vmcg?
MINIMUM CONTROL SPEED on the GROUND;
The CALIBRATED airspeed during takeoff RUN at which, when CRITICAL ENGINE is SUDDENLY INOPERATIVE it is possible to MAINTAIN CONTROL of aeroplane using PRIMARY AERODYNAMIC CONTROLS ALONE for takeoff to continued SAFELY using NORMAL piloting SKILL
How is Vmcg determined?
What are the conditions for determining Vmcg?
The path from which the CRITICAL ENGINE is made INOPERATIVE to a point where RECOVERY PARALLEL to the CENTRELINE is completed may NOT DEVIATE MORE than 30ft LATERALLY;
TAKEOFF CONFIGURATION or in the MOST CRITICAL TAKEOFF CONFIGURATION;
MAXIMUM AVAILABLE takeoff POWER or THRUST;
MOST UNFAVOURABLE CoG;
TRIMMED for TAKEOFF;
MOST UNFAVOURABLE WEIGHT in takeoff weight range
What is Vmca?
MINIMUM CONTROL SPEED in AIR;
The CALIBRATED airspeed when CRITICAL engine is SUDDENLY INOPERATIVE, it is possible to MAINTAIN CONTROL and maintain STRAIGHT flight with ANGLE of BANK NOT MORE than 5 degrees
What are the conditions where Vmca must not exceed 1.2 Vs?
MAX available TAKEOFF POWER/THRUST;
MOST UNFAVOURABLE CoG;
TRIMMED for TAKEOFF;
MAX SEA-LEVEL TAKEOFF WEIGHT;
MOST CRITICAL TAKEOFF CONFIG after airborne except with GEAR RETRACTED;
Aeroplane AIRBORNE and NEGLIGIBLE GROUND EFFECT;
Must not assume any DANGEROUS ATTITUDE or a HEADING CHANGE of MORE THAN 20 degrees
What is Vmcl?
MINIMUM CONTROL SPEED for APPROACH and LANDING;
The CALIBRATED airspeed when CRITICAL engine SUDDENLY INOPERATIVE it is possible to MAINTAIN CONTROL and maintain STRAIGHT flight with ANGLE of BANK NOT MORE than 5 degrees
What must Vmcl be established with?
MOST CRITICAL CONFIG for APPROACH and LANDING with ALL ENGINES operating;
MOST UNFAVOURABLE CoG;
TRIMMED for APPROACH with ALL ENGINES operating;
MOST UNFAVOURABLE WEIGHT;
GO AROUND THRUST SETTING on operating ENGINES;
LATERAL CONTROL sufficient to ROLL from STEADY STRAIGHT through 20 degrees AWAY from INOPERATIVE ENGINE in NO MORE than 5 seconds
What is Vmu?
What are the 2 different Vmu? What is the relationship between the 2?
MINIMUM UNSTICK SPEED; The CALIBRATED airspeed AT and ABOVE the aeroplane can SAFELY LIFT OFF and continue TAKE OFF; Vmu(N): ALL ENGINES operative; Vmu(N-1): 1 ENGINE inoperative; Vmu(N) =/< Vmu(N-1)
What is Vmu limited by?
For LONGER aeroplanes: TAILSTRIKE;
For SHORTER aeroplanes: STALL/MAX CL
What is the difference between Vs1g/Vsr and Vs?
Vs1g/Vsr: STALL SPEED when CL is MAX and LOAD FACTOR is EQUAL to 1 used by FLY BY WIRE aeroplanes;
Vs: CONVENTIONAL STALL when LIFT suddenly COLLAPSES and LOAD FACTOR becomes LESS than 1
What is the relationship between Vs and Vs1g?
Vs = 0.94 x Vs1g
What is DOW?
DRY OPERATING WEIGHT;
The TOTAL WEIGHT of an aircraft ready for an operation EXCLUDING ALL USABLE FUEL and TRAFFIC LOAD
What is ZFW?
ZERO FUEL WEIGHT;
The WEIGHT of TOTAL TRAFFIC LOAD (payload including cargo loads, passengers and passenger’s bags) PLUS the DRY OPERATING WEIGHT ie: DOW + TRAFFIC LOAD
What is LW?
LANDING WEIGHT;
The WEIGHT LANDING at DESTINATION;
ZFW + RESERVES
What is TOW?
TAKEOFF WEIGHT;
The WEIGHT at TAKEOFF at departure;
LW + TRIP FUEL or;
ZFW + TAKEOFF FUEL (fuel needed at the brake release point including reserves)
What is taxi/ramp weight?
TOW + TAXI FUEL
How is max takeoff weight determined?
FLIGHT STRUCTURE RESISTANCE criteria;
RESISTANCE of landing GEAR;
STRUCTURE criteria during a LANDING IMPACT with a VERTICAL SPEED equal to -1.83 m/s (-360 feet/min)
How is max landing weight determined?
By a LANDING IMPACT with a VERTICAL SPEED equal to -3.05 m/s (-600 feet/min)
How can the MTOW and MLW be represented in equations with actual takeoff and landing weights?
ACTUAL LW = TOW - TRIP FUEL =/< MLW;
ACTUAL TOW =/< MLW + TRIP FUEL
Why is a MZFW required?
BENDING MOMENTS that apply at WING ROOT are MAX when FUEL is MIN when FUEL DECREASES in flight the MOMENT INCREASES therefore weight with zero fuel must be LIMITED;
ACTUAL TOW =/< MZFW + TAKEOFF FUEL
Briefly describe the concept of environmental envelope?
Shows the FLIGHT, STRUCTURAL, POWER PLANT, FUNCTIONAL or EQUIPMENT CHARACTERISTICS at extreme TEMPERATURES and PRESSURE ALTITUDES
What is the main cause of engine limitations?
What are the limits for takeoff/go-around, max continuous thrust and climb operating conditions?
EXHAUST GAS TEMPERATURE;
TOGA: MAX 10 minutes with ENIGNE FAILURE, or 5 minutes with ALL ENGINES OPERATIVE;
MCT: UNLIMITED in flight, MUST be selected in ENGINE FAILURE, when TOGA thrust is NOT ALLOWED due to TIME LIMIT
CL: UNLIMITED in CLIMB PHASE to the cruise flight level, is GREATER THAN MAX CRUISE THRUST AVAILABLE during CRUISE PHASE
How does temperature and pressure altitude related to takeoff thrust?
TEMPERATURE: At a given PA, TEMPERATURE has NO EFFECT on THRUST until Tref, beyond Tref an INCREASE in TEMPERATURE, leads to a DECREASE in THRUST AVAILABLE due to EGT;
PRESSURE ALTITUDE: At a given TEMPERATURE any INCREASE is PA will cause a DECREASE in THRUST AVAILABLE
