ATIS: Automatic terminal information service, broadcasts essential information like weather, active runways, available approaches, etc.

  • (Voice) ATIS: tune in the frequency to listen
  • D-ATIS: Data-link ATIS, is text-based, can be displayed on an electronic display in the aircraft


Level 50 = 5000 feet


VHF omnidirectional range (VOR uses band from 108.00 to 117.95 MHz). Short-range radio navigation system, on the ground. Stations are being decommissioned with widespread adoption of GPS


Distance measuring equipment. Different from VOR, DME operation will continue and possibly expand as an alternate navigation source to space-based navigational systems such as GPS and Galileo.

The fifth-generation equipment proposed in 2020 provides greater accuracy (down to 5 meters using DME/DME triangulation), with a further reduction to 3 meters using a further refinement.



flight management system


The “parts” refer to the parts of the Federal Aviation Regulations (FAR). The FARs are found under Title 14 (Aeronautics and Space) and Title 49 (Transportation) within the Code of Federal Regulations (CFR), which is US Federal Law.

It is important to note that Title 48 of the Code of Federal Regulations (CFR) is titled “Federal Acquisitions Regulations” (also FAR). The two identical acronyms have created confusion, leading the Federal Aviation Administration (FAA) to refer to regulations as “14 CFR part XY.”

The “parts” referred to are parts of the FAR. The FAA refers to the parts of the FAR as “14 CFR part XY,” not “FAR part XY,” as it is colloquially used.

Code of Federal Regulation (CFR)

Title 14 of the CFR (14 CFR): Aeronautics and Space

Chapter 1 of Title 14: FAA, Department of Transportation

Subchapter D Airmen, Part 61: "Certification: Pilot, Flight Instructors and Ground Instructors" (14 CFR part 61) for non-certificated flying schools and independent flight instructors.

Subchapter H Schools and Other Certificated Agencies, Part 141 "Pilot Schools" (14 CFR part 141) for FAA certified schools

The FAR is the book of Federal Aviation Regulations, and the AIM is basically a textbook with further information consisting of several topics in individual chapters.s


NDB is being phased out.

FBO: Fixed-base operator

  • operate at the airport.
  • provide aeronautical services: fueling, hangaring, tie-down and parking, aircraft rental, aircraft maintenance, flight instruction, etc.

Radar and Transponders


  • Primary Radar: ground-based, detects objects, to show dots in ATC
  • Secondary Radar (Secondary Surveylance Radar or SSR): ground-based, asks the transponder to transmit a return signal. From ground to airborne at 1030 MHz, from airborne to groun at 1090 MHz.
  • Traffic collision avoidance system (TCAS): airborne system, interprets transponder returns of nearby aircraft, to show in displays and warn collisions.


  • Mode A: no altitude ("On").
  • Mode C: with altitude ("Alt").
  • Mode S: use 24-bit (more than 16 million codes, comparing to 4096 codes in classic modes); use data link communication.

Special Sqawk code:

  • 1200: VFR default
  • 7500: Highjik
  • 7600: Radio failure
  • 7700: Emergency


Part of NextGen

  • Automatic: works in background.
  • Dependent: depends on other aircraft being equipped (FAA mandates ADS-B Out in 2020).
  • Surveillance: to track other aircraft.
  • Broadcast: it sends out its position and velocity.

In vs Out

  • Out: aircraft report position, velocity, altitude once per second, the 2020 mandate.
  • In: receive weather and traffic, not part of the 2020 mandate.


  • 1090ES (Extended Squitter): same as Mode A/C trasnponder; Mode S transponders can be upgraded to ES transponders by adding a WAAS GPS and upgrading software; accepted outside the US; above 18,000 ft; for turboprops and jets
    • In: detect other 1090ES equipped aircraft, or receive traffic from ground stations; no weather
  • 978UAT (Universal Access Transceiver): only allowed in the US and only below 18,000 ft; for general aviation / pistons mostly.
    • In: detect other 978UAT equipped aircraft, or receive traffic from ground stations; can receive ADS-B weather


  • very low cost.
  • very high accuracy performance and control on large airspace.
  • simple ground station design.
  • ADS-B uses a unique code assigned to the airframe for it's life; squawk code is temporary.
  • With ADS-B, pilots can see what controllers see: displays showing other aircraft in the sky.
  • Cockpit displays also pinpoint hazardous weather and terrain, and give pilots important flight information, such as temporary flight restrictions.



Automatic Dependent Surveillance – Contract (ADS-C). ADS-C is similar to ADS-B, but is used primarily for making position reports.



Garmin is playing a big role in general aviation. Garmin covers these 5 segments (ordered by growth rate in 2020Q1), Aviation is not the largest however is the most profitable.:

  • Fitness +24%
  • Marine +22%
  • Outdoor +14%
  • Aviation +10%
  • Auto -17%

Flight Instruments

  • Pitot tube measures both static pressure (ambient pressure / barometric pressure) and dynamic pressure
  • Airspeed Indicator (ASI) uses both static and dynamic pressure
  • Vertical Speed Indicator (VSI) and Altimeter use only static pressure
  • 1 inch of pressure is equal to approximately 1,000 feet of altitude. E.g. if altimeter is not adjusted from 29.94 to 29.69, 29.94-29.69=0.25, 0.25 × 1,000 feet = 250 feet. the aircraft would be approximately 250 feet below the proper traffic pattern altitude. When the actual pressure is lower than what is set in the altimeter window, the actual altitude of the aircraft is lower than what is indicated on the altimeter

Airport Frequencies

An airport with a tower usually have tower and ground freq, some large airports also have ramp freq to handle taxiway to gate communication.

The individual airline-tenants control their own ramps, otherwise the airport ATC is responsible for ramp traffic.

ATIS / D-ATIS: weather and other info.

CTAF: when there's no tower; often the same as the tower freq.

UNICOM (universal communications): air-ground, operated by a non-air traffic control private agency to provide advisory service.


Wx is the abbreviation for weather in the US.


Two-way data-link system: by which controllers can transmit non urgent strategic messages to an aircraft as an alternative to voice communications.