Sectional Charts

By Bill Hughes

What is the edition date of the sectional chart you always carry in your balloon? What! You don’t always carry one. Why not? Hopefully I can convince you that you want to carry one on all your flights, and maybe even have a second one with the chase vehicle.

Right near the top of the title page on the chart is the edition date. Charts are updated every six months (except for Alaska) so you can easily determine how current your chart is. Why is current important? A typical six-month cycle update will contain 300 changes in aeronautical information (frequencies, airspaces, etc.) and 200 changes in base information (obstructions, city boundaries, etc.). So you dug down to the bottom of your storage pouch in the balloon and found what once was a sectional chart and is now a curled up, wad of paper that tears and falls to pieces as you try to open it, and the edition date is somewhere in 1996. Since it was published, approximately 8,000 changes have occurred. Now picture yourself conversing with the FAA Inspector, with this wad of paper in your hand, asserting that you had complied with 91.103 and had “all available information” concerning the flight you just made. The vast majority of the changes have no bearing on your flight, but you cannot know if they do unless you have a recent chart.

The sectional charts were first published 75 years ago evolving into their current form through nearly a hundred editions each. Earlier charts were published by the Postal Service for airmail pilots, and these were followed by the Strip Airway Map covering 31 primary air routes in the US. If, in those days you were flying outside those specified routes there were no aeronautical charts to use. Fortunately by then the automobile had become prevalent enough that auto road maps were available for many areas of the country. Airplane pilots of those days tended to start with a road map and mark landmarks visible from the air on them. Many towns painted the name of their town on a water tower or it could be found on the roof of a nearby barn. Whenever you met another pilot one of the first things was to share map information so you could keep your map updated. And yes I still have my pin holed map of the Gulf.

In the mid 60’s I spent some time flying helicopters to offshore oil rigs in the Gulf of Mexico. At the time there was no published map that showed the locations of the hundreds of oil platforms. There was a map available that had a grid overlaying the Gulf with the names of the areas given them for lease purposes. Before flying offshore you borrowed another pilots map. You laid it over top of your new blank map and using a straight pin punched through both maps to transfer the locations to your map. We flew up to 100 miles offshore with no navigation aids, so you wanted to have an accurate map. In a way we keep that tradition alive when we have a fellow balloon pilot visit our flying area by showing them where the local red zones are.

You can be part of the present updating process. Every chart contains information on how you can submit a correction or update. There is a toll free number, an email address, and a postal address where you can send in a chart with corrections on it, and, they will send you a replacement chart free. The Airport/Facilities Directory, which is published every 56 days, will contain changes made but not published on the map yet. With a heightened security mood within the government, breaches of sensitive airspace will likely result in harsh penalties.

Now that you have a current chart, how good are you at reading it? Can you identify the airspace in any area? How about those special military activity routes? The legend page has the most common features identified and you are probably familiar with most of the features in your local flying area. There is a source for a legend showing every feature on a sectional chart, the Aeronautical Chart Users Guide, but very few pilots have ever seen it. You can download a copy free at: www.naco.faa.gov/indes.asp>xml=naco/online/aero_guide

Some interesting information you can glean from it: The shading you see on terrain is always depicted as though the sun was in the northwest. Most obstructions less than 200 feet above ground are not depicted on the chart. Although there are symbols for parachute jumping, glider, ultralight, and hang glider activity areas there is not one for balloons. Anyone want to start a little lobbying action?

Any time you fly outside your local area the Sectional should be one of the things you should consult. You certainly want to know what class airspace you are starting in and what class you may encounter enroute. Identify landmarks that will mark your transition between classes. If you expect to encounter any controlled airspace you should preprogram the appropriate frequencies into your VHF radio. Adding the local ASOS/AWOS frequencies is a good idea.

What do you do with that old chart that you replaced with an updated one? Keep it in the chase vehicle. Teach your chase crew how to read the chart. There are often great landmarks on the sectional and not on road maps, that will help you coordinate the retrieval. You might even use the sectional to update the local road map with such points. In that many crew people eventually become pilots developing skills in this area will serve them well.

Hopefully through the magic of digital technology some day we will be able to obtain aeronautical charts that cover selectable small area where we fly, in a downloadable form with all the information that is relevant to our flight in the same way that we get our weather briefing online now. And it would include the weather.

(for a sidebar)

An area you might want to avoid

Another area you might want to avoid if you want to stay dry

And an area you should stay 2000’ AGL above

If you are curious why the shading is depicted from the Northwest just turn this page upside down and you will see, it looks unnatural.