WHY YOU NEED A FLIGHT CONTROLS CHECK BEFORE EVERY FLIGHT

The Cessna 172 started its takeoff roll, but just a few seconds in, the pilot knew he had a problem.

He tried aborting the takeoff, but just seconds later in a light crosswind, he departed the right side of the runway. The aircraft went through the grass, and eventually into a group of trees.

Fortunately, the pilot only had minor injuries, but the same couldn’t be said about the plane he was flying.

HERE’S THE NTSB’S ANALYSIS:

The pilot reported that during the takeoff roll, he tried to abort the takeoff because he had not removed the bolt he had placed in the yoke for a gust lock. He reported that the crosswind pushed the airplane off the right side of the runway into the grass, the airplane impacted trees, and sustained substantial damage to both wings and the empennage. The pilot reported that the accident was due to him not removing the bolt in the yoke.

HOW A TURBOPROP ENGINE WORKS

Turboprop engines combine the reliability of jets, with the efficiency of propeller driven aircraft at low to mid altitudes. Found on anything from a 50+ seat passenger aircraft to a single pilot cropduster, turboprop engines are perfect for safe, efficient regional travel. This is how they work…

Of all turboprop engines, one of the most popular is the Pratt & Whitney PT6. More than 41,000 PT6A engines have been produced since the family entered service in the 1960s, accumulating over 335 million flying hours. The 69 PT6 models range in power from 500 shaft-horsepower (SHP) to over 2,000 SHP. While not all turboprop engines work exactly like the PT6, they all follow the same basic concepts. Because of its widespread popularity, it’s a great example to focus on.

REVERSE FLOW

Unlike turbofan or turbojet aircraft, air moves through turboprops like the PT6 by reverse flow.

3 RULES-OF-THUMB FOR FLYING IN HOT WEATHER

When the weather gets hot, these rules-of-thumb can help.

1) DENSITY ALTITUDE INCREASES OR DECREASES ABOUT 120 FEET FOR EACH 1°C FROM ISA

If the temperature rises 1 degree from ISA (ISA=15°C at sea level), your density altitude goes up about 120 feet. So if it’s 30°C at sea level, your density altitude is going to be about 1,800′. (30°C-15°C = 15°C above ISA, 15 X 120 = 1,800)

But keep in mind, ISA decreases 2°C per thousand feet. This is important for airports that aren’t at sea level.

Let’s take Denver Centennial, for example, at 5,885′ field elevation. To make the math easy, we’ll round up to 6,000′.

At 6,000′, ISA isn’t 15°C, it’s actually 3°C.

So if it’s 30°C at Denver Centennial, you’re 27°C above ISA, and the density altitude is roughly 9,240′. That’s an increase of more than 3,200′ over field elevation.

The higher your airport, the bigger the difference a hot day makes.

THE 4 STEPS OF SPIN RECOVERY, EXPLAINED

Have you ever practiced a spin? If you have (and even if you haven’t), you’ve probably heard the recovery acronym “PARE”. But do you know what each step is for?

FIRST OFF, WHAT EXACTLY IS A SPIN?

Before we jump into the spin recovery steps, let’s take a quick look at what’s happening in a spin. The FAA defines a spin as “an aggravated stall that results in an airplane descending in a helical, or corkscrew path.”

Which brings us to spin point number one: both wings are stalled in a spin, but one is more deeply stalled than the other. The “more stalled” wing is on the inside of the spin, it flies at a higher angle-of-attack, and it generates less lift than the outside wing.

Since your high wing generates more lift than the low wing, it rolls your aircraft into the spin.

HOW DOES A TURBOFAN ENGINE WORK?

When you board an airline flight, you might not spend much time thinking about the engines. But they’re the only reason that 700,000 pounds of aluminum and passengers can hurtle through the air at 80% the speed of sound. So how do they work? Let’s take a look.

THE BASICS

Jet engines, which are also called gas turbines, work by sucking air into the front of the engine using a fan. From there, the engine compresses the air, mixes fuel with it, ignites the fuel/air mixture, and shoots it out the back of the engine, creating thrust.

That’s a pretty basic explanation of how it works, so let’s take a look at each section of a jet engine to see what’s really going on.