Technical Questions Flashcards
What is a Yaw Damper?
Servo that smoothly automates rudder pedals to maintain coordination.
Prevents Dutch Roll. Oscillating turns with opposite roll and yaw.
What Factors affect V1
Weight, pressure altitude, temperature, wind, runway length, runway slope, runway condition, flaps, equipment in use (thrust reverse, icing, ect)
What are N1 and N2?
N1 = Low pressure compressor, how power is set. Intake.
N2 = high pressure compressor, initial power on startup, shows power to systems. Engine core.
What systems are powered by hydraulics?
Flight controls, landing gear, brakes, flaps, spoilers, thrust reverse
What is RVR?
Runway Visual Range = horizontal distance pilot can see down the runway. 3 sensors, reported in feet.
What are some things that effect stall speed?
Load Factor, Weight, CG, Flaps/Slats, wing contamination
How do you increase the stall speed of an airfoil?
Increase Load Factor/AoA, forward CG, Flaps up, wing contamination
Effects of Forward CG
increase longitudinal stability, increase stall speed, less fuel efficient
Effects of Aft CG
Decrease longitudinal stability, decrease stall speed, more fuel efficient
How does altitude affect your stall AOA?
Air density decreases, lift decreases and stalls at a lower AOA
Why does stall speed increase with altitude?
Air density decreases, airfoil requires more laminar flow (speed) over the wing to create the same amount of lift
Why is it bad for a wing to stall at the wingtip first?
Roll control is lost first
What do flaps do and how do they work?
High lift device, increase wing camber, decreases stall speed, increase drag. Allows for lower AoA on approach without increasing speed.
What is a Mach Number?
Speed of an object in relation to speed of sound
What is Critical Mach?
When any point on the aircraft reaches the speed of sound (usually just below mach 1.0)
How are Critical Mach, Stall speed, and Altitude related?
Stall speed gets faster and speed of sound is slower with altitude. They converge on each other in the coffin (Q) corner. Can have stall buffet or overspeed buffet.
What happens to IAS with increase in altitude?
Decreases
What happens to TAS with increase in altitude?
Increases (air is less dense/less drag)
What happens to Mach Number with increase in altitude?
Mach number changes with temperature: Colder (generally higher altitude) = lower speed of sound = higher mach number
Why does an aircraft lose airspeed in a turn if thrust is not increased?
Vertical lift is traded for horizontal requiring an increase in AOA to maintain altitude. Increase in AoA reduces speed requiring power to compensate.
Swept wing advantages? Particularly jet aircraft?
Increases critical mach number, by delaying wave drag (supersonic shockwaves).
What are the stall characteristics of a swept wing?
Wing tip stalls first, higher AoA at low speeds required if flaps/slats ect not used.
Types of Drag
Induced and Parasitic (Parasitic has skin friction, form, interference). High speed has wave drag.
What happens to the speed of sound as altitude increases?
Speed of sound decreases with a decrease in temperature (standard lapse rate would be colder as altitude increases)
What is Mach Tuck and how is it counteracted?
Shockwaves cause center of pressure to move aft requiring increase in AoA. When shockwaves reach a critical level, elevator effectives is lost due to lack of smooth air flow causing a nose dive. Counteracted by stabilators and vortex generators.
What does critical Mach have to do with Mach tuck?
When critical mach is reached shockwaves begin to form. The lower critical mach is the sooner mach tuck is likely to occur.
What is a dutch roll?
Rolling and Yawing oscillations: result of dihedral effect overpowering directional stability.
What type aircraft is susceptible to dutch roll?
Swept Wing
How do you counteract dutch roll?
Dutch roll is typically dynamically stable. Usually can relax controls and let the yaw dampener recover.
Holding speeds
0-6000 = 200 knots
6001-14000 = 230 knots
14000+ = 265 knots
What happens to TAS and IAS as you Climb at a constant Mach
Decreases
Maximum intensity stage of a thunderstorm
End of mature stage
What does a swept wing do?
Faster airfoil speed before critical Mach is reached
Where does RVSM airspace start and end?
FL290 to 410
When do you need a takeoff alternate?
Weather below landing minimums at departure airport. Alternate must be within one hour at normal cruise speed with OEI in still air.
Types of icing fluids
Type 1: de ice
Type 4: anti ice
What does daytime beacon mean at a towered airport?
Visibility less than 3 miles or ceiling less than 1000 feet.
What are slats?
Leading edge device that energizes the boundary layer and changes camber to lower stall speed.
What is the MSA and what does it provide you?
Lowest altitude used: 1000ft clearance on all obstacles in the sector.
Speed restriction inside C/D airspace
200 knots
Types of Airmets
Zulu = icing
Sierra = IFR
Tango = turbulence
Where must you be on an approach to continue if weather goes below minimums?
Inside the FAF
When is the ILS Critical Area in effect?
Weather is either below 800 ceiling or 2 miles visibility and aircraft is on approach past the outer marker.
How do you know when a cold front has passed?
Wind shift and temp change
How long are standard hold legs?
Below 14000 = 1 min
Above 14000 = 1.5 min
What does the D stand for in D-ATIS
Digital
What is ADIZ
Air Defensive Identification Zone
How does a Jet Engine start?
Ground Cart. Starter spins compressor/fan, ignition on, air introduced, oil pressure verify and fuel introduce, starter and ignition cut out.
What does pressing the fire button do?
Shutoff valves for fuel and hydraulics, generator off, arms fire bottles.
What is viscous hydroplaning?
Smooth surface hydroplaning (new pavement or rubber coated), thin layer of water and low tire speed. Braking hard causes tires to lock up.
What is an airport reference point? (Circle with a cross)
Geographic center of the airport
When must a crew member breathe oxygen?
FL350 when one leaves station.
FL410 one at all times.
What is the most dangerous type of precip?
Supercooled water droplets
CRJ-900 MTOW
84,500
Centerline light colors
White
Last 3000ft alternate red/white
Last 1000ft red
Standard lapse rate
-2C/3.5F per 1000ft
V2 Speed
Takeoff safety speed. Maintain on climb out to ensure aircraft control and climb gradient are achieved.
MOCA
Nav and obstacle clearance
Speed restriction above 10,000
Mach 1
Speed restriction below 10,000
250 knots
Dimensions of class C
5NM bottom to 4000
10NM shelf 1200-4000
How long before entering a hold should you slow down?
3 minutes
How does a turbine engine work?
Suck - air is drawn in by stage 1 compressor
Squeeze - compresses through several stages into the hot section
Burn - fuel is added and ignited
Blow - hot gas expands through the tailpipe creating thrust
What is a hung start and what should you do?
Engine fails to reach normal idle speed after starting - poor airflow, fuel flow, other mechanical issues. Shut it down.
What is the VDP
Point which descent from the MDA can begin to the TDZ with a 3.0 degree glide path.
What type of turbulence is in the jet stream
Clear air turbulence
