75 votes
Accepted

Explaining a "Great Circle Route" to young Civil Air Patrol cadets

I would recommend that you don't introduce the term first and then try to explain it verbally, but demonstrate it in an interactive, hands-on practical way instead. Bring a globe, a flat map, and a ...
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  • 15.9k
48 votes
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What is significant about the number 8069 ft?

Apparently you aren't the only person who wondered this; the FAA actually has it in an FAQ: What is the significance of a runway 8069 feet in length and why are two different aerodrome symbols used ...
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  • 70.2k
36 votes

What does the "DO NOT USE FOR NAVIGATION" indication mean?

Unless it's an obsoleted procedure chart, it usually means that it's not complete. The example you show has only the features pertinent to that approach, and its missing (for clarity) the features ...
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32 votes
Accepted

What does the snowflake with temperature symbol on an approach plate mean?

From FAA INFO 15002: A [snowflake] -XX°C icon will be incrementally added to airport approach plates, beginning Mar 5, 2015. The icon indicates a cold temperature altitude correction will be ...
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  • 41.8k
29 votes

What does the "DO NOT USE FOR NAVIGATION" indication mean?

When an aviation chart is marked with "DO NOT USE FOR NAVIGATION", it means that ... umm ... it should not be used for navigation. The question is why it should not be, because it appears that the ...
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  • 29.1k
26 votes
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What does "MERMA" mean on the Los Angeles TAC chart?

MERMA is an aviation waypoint Waypoints used in aviation are given five-letter names. These names are meant to be pronounceable or have a mnemonic value, so that they may easily be conveyed by ...
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  • 25.3k
24 votes

What do these white on red words indicate on a London Heathrow taxiway chart?

They are named holding points; this allows them to say things like "taxi to RABIT" rather than "taxiway Bravo, hold short of taxiway Charlie". This saves a lot of time for ground controllers at busy, ...
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  • 25.1k
21 votes

Why does Class D overlap class B around SeaTac? ...and other Seattle Bravo airspace strangeness

This is a great question. For those who are unfamiliar, and in areas where airspace is complex, it’s sometimes useful to look at the VFR Flyway Chart. This is the one on the back of FAA Terminal Area ...
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  • 23k
18 votes
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What does 00 mean on a sectional below the airport runway information?

That is the elevation and length of the longest co-located water runway. Elevation of 00, and runway length 5000 feet. This information is found on page 16 in the current Aeronautical Chart Users ...
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  • 2,750
17 votes

What is "(CFMCC)" on an ILS approach chart?

A point shown in parentheses like this is called a Computer Navigation Fix (CNF). If it didn't fall right at the end of the runway, it would be marked with a small X. It's defined in the legend on ...
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  • 69.7k
17 votes

What organisation owns intersection names?

The allocation of waypoint names is actually handled by each country's individual aviation authority. This means that there are actually duplicates in different countries or regions. The ICAO has made ...
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17 votes

Explaining a "Great Circle Route" to young Civil Air Patrol cadets

What would be an easily understood explanation of a "Great Circle Route" The interest for great circle navigation is a great circle arc between two points is the shortest route between ...
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  • 67.6k
16 votes
Accepted

How do I determine the VFR pattern altitude at an airport?

In April 2013, the FAA's Charting Group met to discuss this question. The standard pattern used to be 800 ft AGL, and the Chart Supplement (formerly called Airport/Facility Directory or A/FD) was ...
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  • 8,127
16 votes

How precisely are airspace borders defined?

The boundaries are defined more precisely than the chart can show. What you see on the chart is a visual representation of the text published in JO 7400.9Z (or the most recent version of it): AWP ...
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  • 70.2k
14 votes
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Why are there out-of-date tower frequencies on the VFR sectional chart, without a NOTAM?

It's not a printing error. FAA sectional charts are updated only once every six months. In order to to reduce the number of NOTAMs due to sectional changes (which can number in the hundreds between ...
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  • 4,977
14 votes
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Why are airspaces depicted in AGL?

You're confusing the airspace height with airspace altitude. The definition of Class C (in the US) is 3-2-4 (a) Generally, that airspace from the surface to 4,000 feet above the airport ...
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  • 16.4k
14 votes
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What does the T in RVR-T stand for?

From page 5-1-7, contractions in the AIM: RVRT . . . . . . . . . RVR Touchdown The full list is: RVR . . . . . . . . . . Runway Visual Range RVRM . . . . . . . . RVR Midpoint RVRR . . . . ....
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  • 57.5k
14 votes
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How many airport charts do airline pilots have in the cockpit?

In the 1990s I flew for two 747 carriers, the first primarily a freight carrier and the second primarily a passenger carrier. Both used Jeppesen for their airway manuals, and both supplied each pilot ...
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  • 38.7k
14 votes
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Where are the "Admitted Aircraft symbols" on Jeppesen VFR aerodrome charts defined?

With the help of Bianfable's answer I took it upon myself to email Jeppesen to get the correct answer.
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  • 10.9k
14 votes
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What is an "Alternate Airway"?

I found an old definition in the All-Weather Flight Manual published by the US Navy in 1957: Alternate Airways Alternate airways are occasionally used for lateral separation when traffic conditions ...
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  • 44k
13 votes
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Why publish an unusable airway?

Short answer: only part of the airway is unusable, and even then it's usable with GPS. Your image shows V522 between FAILS intersection and the ERI VOR but you have to look at the full airway, which ...
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  • 70.2k
13 votes
Accepted

What's a metering fix?

Definitions from this page. Metering: A method of time-regulating arrival traffic flow into a terminal area so as not to exceed a predetermined terminal acceptance rate. Metering airport: Airport ...
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  • 67.6k
12 votes
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What are Runway Declared Distances?

From the AIM, 4-3-6 (c)(2): All 14 CFR Part 139 airports report declared distances for each runway. Other airports may also report declared distances for a runway if necessary to meet runway design ...
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  • 5,201
12 votes
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What is “abnd” on the U.S. VFR Sectional Chart?

ABND, according to the United States of America Aeronautical Contractions means: Abandon A link to this document can be found here: FAA Website
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  • 17.1k
12 votes

Does anyone know what this approach chart symbol is?

What you want is the Frontmatter to the Terminal Procedures Publication, and in particular the pages under "Approach Lighting System" -- these document all the various permutations of visual approach ...
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12 votes

What does the "DO NOT USE FOR NAVIGATION" indication mean?

In some countries, administrative and legal reasons require that label, because maps officially usable for navigation may need process used for completion including various warranties, for example: ...
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  • 763

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