Aviation

Airspace from NOTAM text: TFR circles and areas with their limits.

• TFR and NOTAM area

  Draws the area a TFR or NOTAM describes, a circle around packed coordinates or a fix-radial-distance, or a list of points, with its area, bounds, and altitude limits, ready to download as GeoJSON.

From the number on the airspeed indicator to true airspeed and Mach, and back.

• True airspeed from indicated or calibrated airspeed

  True airspeed, Mach, and equivalent airspeed from IAS or CAS, pressure altitude, and outside air temperature, by the exact compressible-flow path, with the 2% per 1,000 ft rule beside it.

• Calibrated airspeed from true airspeed or Mach

  The calibrated airspeed to fly for a true airspeed or Mach number at a pressure altitude and temperature, with Mach, EAS, and impact pressure.

• Total and static air temperature

  Static (outside) air temperature from the total air temperature a probe reads, or the reverse, with the ram rise at your Mach number.

Pressure altitude, the standard temperature for it, density altitude, and cold-day corrections.

• Cold temperature altitude correction

  How much to add to each procedure altitude when the airport is colder than standard, by the ICAO equation, with the 4% rule and the ICAO table beside it.

• Density altitude

  How high the airplane feels: density altitude from field elevation, altimeter setting, and temperature, with optional dew point, and the rules of thumb beside it.

• Flight level and altitude

  The altitude on the local altimeter setting that a flight level puts you at, or the other way round, with the US lowest usable flight level and transition altitude.

• ISA temperature and deviation

  The standard temperature at a pressure altitude (15 °C falling 1.98 °C per 1,000 ft to -56.5 °C), and the ISA deviation of an outside air temperature.

• Pressure altitude

  Pressure altitude from field elevation and the altimeter setting, exact from the standard atmosphere, with the 1,000 ft per inch rule of thumb beside it.

• QNH, QFE, and QNE

  Converts between the altimeter setting (QNH) and station pressure (QFE) at an airport, gives the field's pressure altitude (QNE), and works out the altimeter setting from a barometer reading.

• True altitude

  Your true height above sea level from the altimeter reading when the air is colder or warmer than standard: high to low, look out below.

Pressure, temperature, density, and speed of sound in the standard atmosphere.

• Cloud base and freezing level

  An estimate of the base of convective clouds from the temperature and dew point, by the 400 ft per degree rule and by the lifting condensation level, and of the freezing level.

• Humidity and moist air

  Dew point, relative humidity, and vapor pressure from each other, with the mixing ratio, virtual temperature, and how much lighter the moist air is than dry air.

• Standard atmosphere

  Temperature, pressure, density, speed of sound, and viscosity of the ICAO or US 1976 standard atmosphere at any altitude, on a standard or non-standard day.

Holding, DME, and station geometry for instrument flying.

• DME arc lead points

  Where to start the turn onto a DME arc from a radial, and how many radials early to turn off the arc onto an inbound course, from the arc's DME and your standard-rate turn.

• DME slant range to ground distance

  The distance over the ground to a DME station from the DME reading and your height above the station, and how much the reading overstates it.

• Holding pattern entry

  Which holding entry to fly (direct, teardrop, or parallel) from your heading to the fix, the inbound course, and the turn direction, per AIM 5-3-8, with the headings for each entry.

• Maximum holding airspeed

  The maximum holding airspeed for your altitude from the AIM table (200, 230, or 265 KIAS), or a published limit, with a flag when your planned speed is above it.

• Holding wind correction and timing

  Inbound and outbound headings for the wind, the outbound time that gives a 1-minute inbound leg, and the triple-the-drift rule of thumb beside the exact values.

• Fix from a radial and distance

  The position on a VOR radial at a distance from the station, using the station's published variation, with a warning when today's magnetic field differs from it by more than 1°.

• Heading to intercept a radial

  The heading to fly to intercept a VOR radial inbound or outbound from the radial you are on now, with the intercept angle doubled from the angle off course or set by you.

• Time and distance to a station

  How far and how long to a VOR or NDB from the time a bearing takes to change while you fly square to it, exactly and by the 60-times rule.

Fuel planning with legal reserves, fuel weight, and weight and balance.

• Ballast to move the CG

  How much ballast at a chosen arm brings the CG to a target, and the new total weight.

• Fuel planning

  Fuel for a trip by leg, with taxi and climb allowances, fuel to an alternate, and a reserve from the 14 CFR 91.151 or 91.167 minimum, checked against your usable fuel.

• Fuel weight

  Fuel weight from volume, or volume from weight, for avgas or jet fuel at a nominal density or one you enter.

• Performance table lookup

  Reads a POH performance table of one, two, or three variables, like takeoff distance by altitude, temperature, and weight, between its listed values, refuses to guess beyond them, and applies corrections as labeled steps.

• Weight and balance

  Total weight, moment, and center of gravity from your stations, checked against your CG envelope at takeoff and after the fuel burn.

• Weight shift

  How far the CG moves when you move weight from one station to another, or how much weight to move to put the CG where you need it.

Climb, descent, glide, turns, and range per gallon.

• Climb gradient and vertical speed

  Converts a climb or descent gradient (feet per nautical mile, percent, or degrees) to the vertical speed you need at a groundspeed, or the reverse.

• Glide range with wind

  How far you can glide from a height with your aircraft's glide ratio, in still air and with a headwind or tailwind.

• Pivotal altitude

  The pivotal altitude for eights on pylons at your groundspeed, with the knots-squared over 11.3 rule.

• Specific range

  How far each gallon of fuel takes you, through the air and over the ground, and the fuel each 100 NM takes, from your airspeed and fuel flow.

• Top of descent

  Where to start down: descent distance, vertical speed, and time for an altitude change on a descent angle or at a vertical speed, with the 3-to-1 and 5 × groundspeed rules beside them.

• Turn performance and load factor

  Bank angle, rate of turn, turn radius, load factor, and stall speed in the turn, from true airspeed and a bank angle or turn rate (standard rate by default).

• Visual descent point

  The visual descent point for a non-precision approach: the distance from the threshold where a normal descent from the MDA begins, with the HAT/300 rule and the descent rate at your groundspeed.

METARs, TAFs, and winds aloft, decoded into plain language.

• Winds aloft (FB) decoder

  Decodes FB winds and temperatures aloft: one group at a level, or a whole station line, with light-and-variable winds, speeds over 100 kt, and the implied minus sign above 24,000 ft.

• METAR decoder

  Turns a pasted METAR or SPECI into plain language: wind (true), visibility, weather, clouds and ceiling, temperature, altimeter, US remarks, and the flight category. Groups it cannot read are listed, never dropped.

• TAF decoder

  Turns a pasted TAF into a timeline of forecast periods (FM, TEMPO, BECMG, PROB30/40) in plain language, with UTC and local times, winds (true), visibility, weather, clouds and ceilings, and flight categories.

The wind triangle and runway wind components.

• Winds aloft between levels

  The wind and temperature at your cruising altitude from the forecast levels above and below it, interpolated as a vector so a turning wind turns smoothly.

• Rank runways for the wind

  Headwind and crosswind on every runway at an airport for one wind, ranked by headwind, with runways beyond your limits flagged.

• Wind triangle: course and groundspeed from a heading

  Where a heading and true airspeed will take you in a known wind: the course over the ground, the groundspeed, and the drift.

• Wind triangle: find the wind

  The wind aloft from your heading, true airspeed, track, and groundspeed.

• True course to compass heading

  From true course through the wind correction, variation, and your compass deviation card to the heading to fly on the compass, each step shown.

• Wind triangle: heading and groundspeed

  The heading to fly and the groundspeed you will get for a course, true airspeed, and wind: the E6B wind side, exact.

• Off-course correction (1-in-60)

  How far you have drifted off track, the turn to parallel your course, and the turn to reach your destination, exactly and by the 1-in-60 rule.

• Runway wind components

  Crosswind and headwind or tailwind on a runway, with gusts, variable winds, and your personal limits.

• Wind triangle: airspeed and heading for a groundspeed

  The true airspeed and heading that make good a course at the groundspeed you need, for a known wind.

• Wind components (u and v)

  A wind's east-west (u) and north-south (v) components from its direction and speed, or the direction and speed from u and v, as weather models and forecasts give them.