• flight planning;
• chart-reading (also known as pilotage) which means determining your position over the ground by comparing the ground features with those marked on the chart;
• using navigation aids to assist and confirm your map-reading;
• making corrections to your flight path over the ground so as to regain your planned course and reach your destination; and
• using dead reckoning to back up your other visual navigation methods.

Today, we’ll feature an excerpt from this chapter specifically on chart-reading in flight. Ground School is available in hardcover and in multiple eBook formats.

Chart-Reading in Flight
The success of map-reading depends on four basic factors:

• a knowledge of direction;
• a knowledge of distance;
• a knowledge of groundspeed; and
• the selection and identification of landmarks and checkpoints.

Select good checkpoint features. Landmarks and checkpoints that can be easily identified, and which will be within your range of visibility when you pass by them, are best. Just how conspicuous a particular feature may be from the air depends on:

• the flight visibility;
• the dimensions of the feature;
• the relationship of your selected feature to other features; the angle of observation;
• the plan outline of the feature if you are flying high; and
• the elevation and side appearance of the feature if you are flying low.

Preferably the feature should be unique in that vicinity so that it cannot be confused with another nearby similar feature. A feature that is long in one dimension and quite sharply defined in another is often useful, because:

• if a long feature (such as a railroad, canal or road) runs parallel to your planned course, it can assist in maintaining accurate tracking; and
• if a long feature crosses the course it can be used as a position line to aid in determining an updated groundspeed (GS).

The relationship between your selected feature and other nearby ground features is very important for a positive confirmation of your position. For example, there may be two small towns near each other, but you have chosen as a feature the one that has a single-track railroad to the west of the town and with a road that crosses a river on the north side of the town, whereas the other town has none of these features. This should make positive identification fairly easy.

The post Navigation: Chart-Reading in Flight first appeared on Learn To Fly.

Best performance is achieved by a combination of high levels of skill, knowledge, and experience (consistency and confidence), and with an optimum degree of arousal. Skill, knowledge and experience depend upon the training of the pilot; the degree of arousal depends not only upon the pilot’s flying ability but also upon other factors, such as the design of the cockpit, air traffic control, as well as upon the environment, motivation, personal life, weather, and so on. Low levels of skill, knowledge and experience, plus a poorly designed cockpit, bad weather, and poor controlling will lead to a high mental workload and a poor performance. If the mental workload becomes too high, decision making will deteriorate in quality, or maybe not even occur. This could result in concentrating only on one task (sometimes called tunnel vision) with excessive or inappropriate load-shedding. You can raise your capability by studying and practicing, and by being fit, relaxed and well rested.

The pilot’s tasks need to be analyzed so that at no time do they demand more of the pilot than the average, current and fit pilot is capable of delivering. There should always be some reserve capacity to allow for handling unexpected abnormal and emergency situations. At the aircraft design stage, the pilot is taken to be of an average standard. On this basis, skills and responses are established during testing so that the aircraft can be certificated as compliant. But there is some argument that the specimen should not be the average pilot, because half of the pilot population would be below this standard.

The legislators establish the minimum acceptable standards for licensing but the marginal pilot, who maintains only the minimum required standard, is not really of an acceptable standard. You can each ensure that you are at an acceptable standard by honestly reviewing the demand that the aircraft and the flight placed upon you. If your capabilities, mental or physical, were stretched at all, then you need more practice, more study or more training—at least in those aspects that challenged you. Many pilots feel that, under normal conditions, they should be able to operate at only 40–50% of capacity, except during takeoffs and landings, when that might rise to 70%. This leaves some capacity to handle abnormal situations.

The post Enroute Flight: Mental Workload first appeared on Learn To Fly.

TIME
To determine time you need two pieces of information: distance (in nautical miles) and ground speed (in knots).

Distance / Ground Speed = Time 

How long will it take you to fly a distance of 190 NM at a ground speed of 135 knots?

190/135 = 1.4 hours

To convert the .4 to minutes you need to multiply by 60.

0.4 x 60 = 24 minutes

Your answer is 1 hour and 24 minutes.

DISTANCE
This next calculation is used to determine distance flown in a given time.

Ground Speed (in knots) X Time (in hours) = Distance (in nautical miles)

How far will the aircraft fly in 1 hour and 30 minutes at a ground speed of 120 knots? The first step is to convert the 30 minutes into equivalant hours, instead of multiplying by 60 like we did above, here we will divide by 60 (30/60=0.5).

120 X 1.5 = 180 NM

GROUND SPEED
Lastly, to find ground speed we need to know distance and time.

Distance (in nautical miles)/ Time (in hours) = Ground Speed (in knots)

What is our average ground speed if we travel 250 NM in 2 hours ?

250 / 2 = 125 knots

Here are a few to try on your own.

Problem: What it the approximate time en route for a 60 NM leg with a ground speed of 110?

Problem: How far has the aircraft traveled in 1 hour 24 minutes at a ground speed of 140 knots?

Problem: What is your ground speed if you have covered 200 NM in 1 hour 45 minutes?  

The post CFI Brief: Basic Planning Calculations first appeared on Learn To Fly.

Considering the theory explained in Monday’s post on the wind triangle (vector analysis), let’s discuss a quick and easy way to get back on course using what’s called the off-course correction equation.

I like to think of the above equation as a two part problem. The first part Distance Off x 60 / Distance Flown will give you a degree of heading change to parallel your intended course. Part two Distance Off x 60 / Distance Remaining will give you an added heading change degree to converge on your course at whatever distance remaining you enter into the equation. By adding part one and two together you get your Degrees of Total Correction. This is the degree of heading change you will need to converge back on course at whatever distance remaining you enter. So for example, if you enter a distance remaining of 50 miles you will converge back on your intended course at the 50 mile mark. Let’s work through a problem together.

Problem:
Off Course = 4 miles
Distance Flown = 40 miles
Distance Remaining = 80 miles

Step 1: Take our distance off course of 4 miles and multiply by 60 (4 x 60 = 240).
Step 2: Divide 240 from step one by distance flown of 40 miles (240 / 40 = 6°).

So at this point a 6° heading change would allow us to parallel our intended course. To find the distance to converge back on course we will need to complete the second part of the problem.

Step 3: Take our distance off course of 4 miles and multiply by 60 (4 x 60 = 240).
Step 4: Divide 240 from step one by distance remaining of 80 miles (240 / 80 = 3°).

Our total heading correction to converge would be 6° + 3° = 9°.

Some additional tips and tricks: by properly using a navigation log associated with my flight plan, I will have known approximately how far I have flown and my distance remaining to either my destination or next check point. You may also use an E6-B or CX-2 Flight Computer to determine off-course corrections.

Try one on your own.

Off Course = 2 miles
Distance Flown = 15 miles
Distance Remaining = 22 miles
(Answer posted in the comments section)

The post CFI Brief: Off-Course Correction first appeared on Learn To Fly.

For flight planning purposes you must recognize that although the lines of latitude and longitude on charts are neatly perpendicular and relate to the True North Pole there is nothing in your airplane that relates to True North. The magnetic compass indicates the direction to the magnetic North Pole, which is in northern Canada (Figure 1).

You must take the variation between true north and magnetic north into account when flight planning.

Figure 2 shows isogonic lines, or lines of equal magnetic variation, across the continent. Along the line which passes through Chicago and Key West, a pilot looking toward the North Star or the True North Pole will also be looking toward the magnetic North Pole, and there will be no variation. The line of zero variation is called the agonic line. East or West of that line, the angle between true and magnetic north increases. A pilot in Los Angeles who measures a course line on an aeronautical chart in relation to the longitude lines (or true north) must subtract 14° from that true course to get a magnetic course (“East is least“), while a pilot in Philadelphia will add 10° (“West is best“). You will determine the true course by using your navigation plotter.

The variation on your sectional chart is almost certainly out-of-date. The isogonic lines on current sectionals were last updated in 2005 and will not be updated until 2011. Variations for navaids and airports are “assigned” and do not reflect the actual variation; variation for a VOR or airport can be up to three degrees different from actual variation is a current Airport/Facility Directory. You can get current variation information for airports along your route by going to http://www.ngdc.gov/geomagmodels/Declination.jsp.

Using the Navigation Plotter
A navigation plotter combines a protractor with mileage scales, and they are available in many forms. You use the protractor to measure the angle between a line of latitude or longitude and your course line. Refer to the Seattle sectional chart excerpt at the back of the book. Draw a line from the center of the airport symbol at Easton (A) to the center of the airport symbol at Wenatchee (H). Align the straight edge of your plotter with this course line and slide the plotter until the hole is over a vertical line of longitude; the angle should be approximately 78 degrees, indicating that the true course from Easton to Wenatchee is 078° and that the course for the return trip is 258°.

Deviation
A course, whether identified as true or magnetic, is only a line on a chart linking departure point and destination. For flight planning purposes, you must allow for magnetic influences in the airplane itself and for the effect of wind drift. Because your airplane has some iron and steel components which are affected by the earth’s magnetic field, and because it contains wiring which creates a magnetic field within the airplane itself, the airplane’s magnetic compass develops an error called deviation which varies with aircraft heading. Looking back at Figure 2, it is apparent that the heading of the airplane has nothing to do with magnetic variation — a pilot in Seattle must apply a 20° easterly variation regardless of the direction of flight. Because magnetic deviation is unique to each airplane and is dependent on heading, a compass correction card (Figure 3) must be prepared by accurately lining up the airplane on known magnetic headings, checking the magnetic compass reading, and recording the deviation error for each heading. Small adjustment magnets are provided so that the error can be minimized.

This compass correction table is originally made at the factory but should be re-checked by a mechanic whenever cockpit equipment installations are made. When a pilot has applied variation and deviation to a measured true course, the result is the compass course:

True ± Variation = Magnetic ± Deviation = Compass

Variation is shown on navigational charts to the nearest one-half degree. You will find that rounding off to the nearest whole degree will speed up your calculations without affecting accuracy. If you make long flights over water or featureless terrain, deviation and compass course will be very important to you, and an accurate compass correction card may be a lifesaver. Pilots who fly by reference to the surface (pilotage) will make little use of compass heading except to adjust their gyroscopic heading indicators.

Any difference between an airplane’s planned course and its track over the ground is caused by wind drift. Always compute the wind correction angle first, and then apply variation and deviation, as National Weather Service winds aloft forecasts are always referenced to True North.

The post Enroute Flight: Magnetic Variation first appeared on Learn To Fly.

We use five different techniques to clearly show the shape of the earth and any obstructions: contour lines, shaded relief, color tints, obstruction symbols, and Maximum Elevation Figures (MEF).

1. 1. Contour lines join points of equal elevation. On Sectionals, basic contours are spaced at 500′ intervals. Intermediate contours are typically at 250′ intervals in moderately level or gently rolling areas. Auxiliary contours at 50′, 100′, 125′, or 150′ intervals occasionally show smaller relief features in areas of relatively low relief. The pattern of these lines and their spacing gives the pilot a visual concept of the terrain. Widely spaced contours represent gentle slopes, while closely spaced contours represent steep slopes.

1. 1. Shaded relief shows how terrain may appear from the air. Shadows are shown as if light is coming from the northwest, because studies show that our visual perception has been conditioned to this view.

1. 1. Different color tints show bands of elevation relative to sea level. These colors range from light green for the lower elevations, to dark brown for the higher elevations.

1. Obstruction symbols show man made vertical features that could affect safe navigation. FAA’s Aeronautical Information Management maintains a database of over 1,200,000 obstacles in the U.S., Canada, Caribbean, Mexico, and U.S. Pacific Island Territories. Aeronautical Specialists evaluate each obstacle based on charting specifications before adding it to a visual chart. When a Specialist is not able to verify the position or elevation of an obstacle, it is marked UC, meaning it is “under construction” or being reported, but has not been verified.Sectional Charts and Terminal Area Charts (TACs) typically show manmade obstacles extending more than 200’ Above Ground Level (AGL), unless they appear in yellow city tint. Features considered to be hazardous obstacles to low-level flight are; smokestacks, tanks, factories, lookout towers, and antennas, etc. On World Aeronautical Charts (WACs) only those obstacles at 500’ AGL and higher are charted.
   
   Manmade features used by FAA Air Traffic Control as checkpoints use a graphic symbol shown in black with the required elevation data in blue. The elevation of the top of the obstacle above Mean Sea Level (MSL) and the height of the structure (AGL) is also indicated (when known or can be reliably determined by a Specialist). The AGL height is in parentheses below the MSL elevation. In extremely congested areas, the FAA typically omits the AGL values to avoid confusion.
   
   Whenever possible, the FAA depicts specific obstacles on charts. However, in
   high-density areas like city complexes, only the highest obstacle is represented on
   the chart using the group obstacle symbol to maximize legibility.
   
   Obstacles under construction are indicated by placing the letters UC next to the obstacle type.
   
   Obstacles with high-intensity strobe lighting systems may operate part-time or by proximity activation and are shown as follows:
   
2. The Maximum Elevation Figure (MEF) represents the highest elevation within a quadrant, including terrain and other vertical obstacles (towers, trees, etc.). A quadrant on Sectionals is the area bounded by ticked lines dividing each 30 minutes of latitude and each 30 minutes of longitude. MEF figures are rounded up to the nearest 100’ value and the last two digits of the number are not shown.
   
   When a manmade obstacle is more than 200’ above the highest terrain within the quadrant:
   1. 1. Determine the elevation of the top of the obstacle above MSL.
      2. Add the possible vertical error of the source material to the above figure (100′ or 1/2 contour interval when interval on source exceeds 200′.)
      3. Round the resultant figure up to the next higher hundred-foot level.

   

   When a natural terrain feature or natural vertical obstacle (e.g. a tree) is the highest feature within the quadrangle:

   1. 1. Determine the elevation of the feature.
      2. Add the possible vertical error of the source to the above figure (100′ or 1/2 the contour interval when interval on source exceeds 200′).
      3. Add a 200′ allowance for uncharted or manmade obstacles. Chart specifications don’t require the portrayal of obstacles below minimum height.
      4. Round the figure up to the next higher hundred-foot level.

   

   We’ll be back with more on Thursday!

The post Enroute Flight: Topography first appeared on Learn To Fly.

If we were to convert 10 AM in Seattle to UTC time we would get 1800 UTC. Let’s take a look at how we did that.

Step 1 is to convert our local time to the 24 hour clock.

10:00 AM Local = 1000 Local

Step 2 using the chart below we can determine our time zone conversion of + 8.

1000 + 8 = 1800 UTC

For daylight savings time you would subtract 1, so be careful you understand what time of the year it is.

You may not always have this chart available but you can always find time zone conversions listed in the A/FD under each airport.

Let’s work through a realistic scenario (at least my idea of one). A few friends and I plan on traveling to San Diego, CA from Dallas, TX. We have an afternoon golf tee time at 3 PM local pacific standard time. We have determined the flight will take us 4 hours. If we want to arrive in San Diego at 2 PM local time, when should we leave?

Step 1. Convert 2 PM to the 24 hour clock:

02:00 PM + 12 = 1400 Local

Step 2. Convert 1400 Local to UTC (refer to the chart above):

1400 + 8 = 2200 UTC

Step 3. Since we have already determined that the flight will take us 4 hours, simply subtract the travel time from the UTC time:

2200 – 0400 = 1800 UTC

Step 4. To arrive on time, we must leave Dallas by 1800 UTC. Convert this to local time by referring back to our chart. Dallas is in Central Standard Time, so we would subtract 6 hours:

1800 – 0600 = 1200 (on the 24 hour clock) or 12:00 PM local central standard time

Perfect. We would need to be wheels up in Dallas at 12 PM local. If you think about it, this makes sense too: there is a two hour time gap between the time we leave local (12 PM) and the time we arrive local (2 PM), including the two hour time zone change between Central Standard Time and Pacific Standard Time and we get 4 hours.

The post CFI Brief: Time Zones first appeared on Learn To Fly.

The equator is an imaginary circle equidistant from the poles of the Earth. Circles parallel to the equator (lines running east and west) are parallels of latitude. They are used to measure degrees of latitude north (N) or south (S) of the equator. The angular distance from the equator to the pole is one-fourth of a circle or 90°. The 48 conterminous states of the United States are located between 25° and 49° N latitude. The arrows in the figure below labeled “Latitude” point to lines of latitude.

Meridians of longitude are drawn from the North Pole to the South Pole and are at right angles to the Equator. The “Prime Meridian” which passes through Greenwich, England, is used as the zero line from which measurements are made in degrees east (E) and west (W) to 180°. The 48 conterminous states of the United States are between 67° and 125° W longitude. The arrows in the figure above labeled “Longitude” point to lines of longitude.

Any specific geographical point can be located by reference to its longitude and latitude. Washington, D.C., for example, is approximately 39° N latitude, 77° W longitude. Chicago is approximately 42° N latitude, 88° W longitude.

The meridians are also useful for designating time zones. A day is defined as the time required for the Earth to make one complete rotation of 360°. Since the day is divided into 24 hours, the Earth revolves at the rate of 15° an hour. Noon is the time when the sun is directly above a meridian; to the west of that meridian is morning, to the east is afternoon. The standard practice is to establish a time zone for each 15° of longitude. This makes a difference of exactly 1 hour between each zone.

By using the meridians, direction from one point to another can be measured in degrees, in a clockwise direction from true north. To indicate a course to be followed in flight, draw a line on the chart from the point of departure to the destination and measure the angle which this line forms with a meridian. Direction is expressed in degrees.

Because meridians converge toward the poles, course measurement should be taken at a meridian near the midpoint of the course rather than at the point of departure. The course measured on the chart is known as the true course (TC). This is the direction measured by reference to a meridian or true north. It is the direction of intended flight as measured in degrees clockwise from true north.

As shown in the figure below, the direction from A to B would be a true course of 065°, whereas the return trip (called the reciprocal) would be a true course of 245°.

The true heading (TH) is the direction in which the nose of the aircraft points during a flight when measured in degrees clockwise from true north. Usually, it is necessary to head the aircraft in a direction slightly different from the true course to offset the effect of wind. Consequently, numerical value of the true heading may not correspond with that of the true course. For the purpose of this discussion, assume a no-wind condition exists under which heading and course would coincide. Thus, for a true course of 065°, the true heading would be 065°. To use the compass accurately, however, corrections must be made for a magnetic variation and compass deviation.

The post Enroute Flight: Latitude and Longitude first appeared on Learn To Fly.

Have a specific problem you want to see worked out on the CX-2 or one of our E6-B flight computers? Let us know!

We will be back Monday with more flight training insights. Until then, have a happy New Year!

The post Calculating Time En Route on the CX-2 first appeared on Learn To Fly.

We will be taking Thursday off, but be sure to check back Monday for another video tutorial on using the CX-2! Happy Holidays!

The post Calculating Fuel Burn on the CX-2 first appeared on Learn To Fly.