🔍 Key Comparisons

• DA vs MDA
  • DA: Used with vertical guidance; missed approach is initiated at the decision altitude if visual references are absent.
  • MDA: Used for LNAV, circling, and other non-precision procedures.

• Simplex vs duplex
  • Simplex: One frequency for transmitting and receiving.
  • Duplex: Simultaneous transmission on one frequency and reception on another.

• FSS vs TRACON vs ARTCC
  • FSS: Briefings, flight-plan processing, and clearance delivery.
  • TRACON: Terminal radar services and transition between departure and en-route airspace.
  • ARTCC: IFR separation in the en-route structure.

• Induced drag vs parasite drag
  • Induced drag: Results from lift creation; increases with angle of attack and decreases with airspeed.
  • Parasite drag: Includes skin-friction, interference, and form drag; increases with speed.

• Normal command vs reversed command
  • Normal command: Additional power is required to increase speed.
  • Reversed command: Additional power is required to maintain a slower speed.

• Structural icing vs induction icing
  • Structural icing: Ice accumulates on exterior aircraft surfaces.
  • Induction icing: Ice forms in the engine induction system and reduces airflow to combustion.

• Clear ice vs rime ice
  • Clear ice: Relatively slow freezing; glossy and transparent.
  • Rime ice: Rapid freezing; milky, opaque, and porous.

• Pressure altitude vs density altitude
  • Pressure altitude: Height above the standard datum plane where pressure equals 29.92 inHg.
  • Density altitude: Pressure altitude corrected for nonstandard temperature.

• IAS vs CAS vs EAS vs TAS
  • IAS: Raw ASI reading.
  • CAS: IAS corrected for instrument and position errors.
  • EAS: CAS corrected for pitot-tube compression.
  • TAS: CAS corrected for nonstandard pressure and temperature.

• VOR vs DME
  • VOR: Provides navigation information used for Victor and Jet airways.
  • DME: Provides distance to a NAVAID and helps identify intersections.

• ODP vs SID
  • ODP: Obstacle clearance; may be flown without ATC clearance when no SID is assigned.
  • SID: Traffic management and standardized routing; requires ATC clearance.

• TCAS I vs TCAS II
  • TCAS I: Issues traffic advisories.
  • TCAS II: Issues traffic advisories and resolution advisories commanding climb or descent.

• GPWS vs TAWS
  • GPWS: Uses radio altitude, speed, and barometric altitude and may be limited in mountainous terrain.
  • TAWS: Adds GPS position and a terrain database for predictive, time-based warnings.

• Attitude indicator vs heading indicator
  • Attitude indicator: Displays immediate pitch and bank attitude.
  • Heading indicator: Displays heading but is not north-seeking and requires periodic alignment.

• Control vs performance instruments
  • Control instruments: Show immediate attitude and power changes.
  • Performance instruments: Show actual aircraft performance.