## Cruising Altitude

When flying anywhere you need to climb, cruise, and then descend. But you must comply with the rules and fly at certain predetermined altitudes.

# The Rules: Neodd and Sweven

When you are flying above 3000 feet AGL you must fly at an even-numbered thousand feet if you are traveling west. That is what sweven means. If you are traveling directly South, or on any Westerly heading then fly on the even-numbered thousands.

Conversely, if you are traveling East or directly North, fly at an odd thousand (neodd).

For IFR flights to the East you will fly at 5000 or 7000 or 9000 feet, etc….

For VFR flights you must be 500 feet above these altitudes. So a VFR flight to the West would cruise at 4500 or 6500 or 8500 feet, etc….

These rules are for cruising altitude, meaning that if you are flying up above 3000 to practice an emergency descent then you can just climb to whatever altitude you want.

# Why is this rule in place?

This rule is a bit of a compromise between safety and simplicity.

When two planes approach head-on their closure speed, the speed at which they are approaching each other, is very high. Even a relatively slow 152 will approach another 152 at around 180 knots TAS if they are head-on. For faster planes like an arrow traveling at 150 knots the closure speed is 300 knots!

It is safer to fly at these altitudes because VFR planes flying East will always be 1000 feet vertically separated from VFR planes flying West. Furthermore, they will be separated by 500 feet from all IFR traffic.

This is great, but there is a problem! What if planes approach nearly head-on but both traveling East? One of them could be traveling 010 degrees (which is East of North) and the other could be flying at 170 (which is East of South).

This is where the compromise comes in. The rule could split the compass into 4 segments but then it would be more complicated and difficult to remember.

Always stay vigilant looking for traffic that might be climbing/descending, not following the rules, or might be at a near head-on angle.

# How low can you legally go?

In very sparse areas, you can fly as low as you want but you must be high enough to make a safe emergency landing. 91.119(a)

If there is any kind of human presence, including people or property, then you must be at least 500 feet away from them or 500 feet above. This is pretty low. Use the ground elevation and your altimeter to determine your height above the ground. 91.119(c)

In most places there are people and structures spread out, so 500 feet above should be considered the limit. The 500 feet away rule really only applies over open water and truly empty areas of land. Continue reading “How low can you fly?”

## Flight Instruments: Vertical Speed Indicator

The Vertical Speed Indicator (VSI) displays the rate of climb or descent measured in thousands of feet per minute. It is considered to be a secondary instrument because it can generally be inferred from the altimeter. It is also considered to be unreliable in many circumstances because it has a delay.

## Flight Instruments: Altimeter

Your height above the terrain and in relation to other aircraft is critically important. The altimeter is an amazing instrument that makes it easy to tell what your altitude is.

# How to read an altimeter

There are 3 needles on this standard altimeter. The long needles pointing near the 7 moves the fastest and indicates hundreds of feet. The short needles pointing near the 1 indicates thousands and the thin needle pointing near 0 indicates tens of thousands. Continue reading “Flight Instruments: Altimeter”

## Vx and Vy

Airplane manufacturers have done a lot of work carefully testing their planes to find out how they perform. It is important to become familiar with their findings to improve safety and performance. Vx and Vy are very important speeds to understand. Continue reading “Vx and Vy”

## Short Field Takeoff

Departing from a short field is an important skill for any pilot. There is a standard procedure to follow and plenty of factors to consider.

The procedure to depart from a short field can be found in the Pilot’s Operating Handbook for the aircraft. However, it will go something like the following for most light aircraft. Continue reading “Short Field Takeoff”