The Airplane Propellor

One thing that I have found fascinating about the propellor is the way that it is shaped. Its shape represents a symbolic icon in flight and aviation. No matter what color, what size, what material the extractated twist of the blade from the blade tip to the root is undisputedly recognizable by anyone inside or outside the aviation community.

Investigating beyond overall look of the propellor is even more enthralling. The propellor is actually shaped like a wing. if you were to study the form characteristics of the blade to that of the surface area of a wing, you will quickly discover  similarities. Specifically, from the leading edge on top of the prop and the would exhibit the same curvature and design features, more rounded, where as the bottom, is a more flat surface. This is because, like the wing of an airplane, the prop is also responsible for generating lift. Looking further, the root of the prop blade is noticeably  more twisted, giving it iconic view as we discussed earlier.  The reason is because in order for lift to occur, the pressure on one side of the blade needs to be lower than the other side. Air traveling over the top of the wing has a greater velocity than the air below the wing, thus lower pressure resulting in life. Since the wing of an airplane is typically uniform and all surface area’s are impacting the air at the same velocity, lift is equal. However, unlike a wing, the propellor takes on different characteristics.  The propellor is not traveling through as much air evenly across the entire suirface. Namely, the tip of the prop is traveling through more particle of air than the root of the prop. The tip is covering a greater radius, than the root. Therefore, in order for the root of the prop to generate the same amount of lift as the tip of the propellor, it needs to have a much greater higher angle of attack, creating more lift.

178 Seconds to Live

How long can a pilot who has little or no instrument training expect to live after he flies into bad weather and loses visual contact? Researchers at the University of Illinois did some tests and came up with some very interesting data. Twenty student “guinea pigs” flew into simulated instrument weather, and all went into graveyard spirals or rollercoasters [a tribute to the U of I flight training program??]. The outcome differed in only one respect - the time required till control was lost. The interval ranged from 480 seconds to 20 seconds. The average time was 178 seconds — two seconds short of three minutes. 

Here’s the fatal scenario. . . . . . . 

The sky is overcast and the visibility is poor. That reported five mile visibility looks more like two, and you can’t judge the height of the overcast. Your altimeter tells you that you are at 1500 feet but your map tells you that there’s lcoal terrain as high as 1200 feet. There might be a tower nearby because you’re not sure how far off course you are. But you’ve flown into worse weather than this, so press on. 

You find yourself unconsciously easing back just a bit on the controls to clear those towers. With no warning, you’re in the soup. You peer so hard into the milky white mist that your eyes hurt. You fight the feeling in your stomach. You try to swallow, only to find your mouth dry. Now you realize you should have waited for better weather. The appointment was important, but not all that important. Somewhere a voice is saying, “You’ve had it — it’s all over!” 

You now have 178 seconds to live. 

Your aircraft feels on even keel but your compass turns slowly. You push a little rudder and add a little pressure on the controls to stop the turn but this feels unnatural and you return the controls to their original position. This feels better but now your compass is turning a little faster and your airspeed is increasing slightly. You scan your instruments for help but what you see looks somewhat unfamiliar. You’re sure that this is just a bad spot. You’ll break out in a few minutes. (But you don’t have a few minutes left. . .) 

You now have 100 seconds to live. 

You glance at your altimeter and you are shocked to see it unwinding. You’re already down to 1200 feet. Instinctively, you pull back on the controls but the altimeter still unwinds. The engine is into the red and the airspeed, nearly so. 

You have 45 seconds to live. 

Now you’re sweating and shaking. There must be something wrong with the controls; pulling back only moves the airspeed indicator further into the red. You can hear the wind tearing at the aircraft. 

You are about to meet your Maker; you have 10 seconds to live. 

Suddenly you see the ground. The trees rush up at you. You can see the horizon if you turn your head far enough but it’s at a weird angle — you’re almost inverted. You open your mouth to scream but. . . . . .

. . . .you just ran out of seconds. 

Think about it before you press on into marginal weather. 

Flight up to Fort Collins

My buddy Cory and I took 64332 up to Fort Collins today for a couple of hours and shot the ILS back into Centennial.

Here’s a quick video I made of the flight.

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Quick Video of my friends Checkride for his Pilot’s License

Landing at Redlands Airport

This is perhaps one of the best pictures I have ever taken. It was with a cheap digital camera. The skyline is red because of all the wildfires in Southern California back in 2004. The airport is Redlands. This is a Cessna 172 that I hobbed about 150 hours, got my private and instrument ratings in.