The very notion of flight amazes us humans even after a century has gone by since we took to the air in the December of 1904.

It gives me immense pleasure to show children the concept of how lift is produced. Not so long ago I took it upon myself to devise a simple experiment to demonstrate the compelling power of air flow over an airfoil.

I used a piece of trim and shaped to serve as a symmetric airfoil. Attach it to a stand so that it doesnt have to be held by hand. Place this device on top of a sensitive kitchen weighing scale. Note the reading on the scale.

Take a home hair dryer. Research the specifications for the dryer to find the air flow velocity from the dryer. If this cant be found, the typical air velocity of a standard hair dryer ranges between 5 m/s and 15 m/s can be used.

Run the hair dryer and point the air flow over the airfoil while it is still placed on the kitchen scale. As the air flows over the airfoil, the weighing scale reading will begin to change – it will show a drop in weight. The drop in weight is on account of the lift being produced by the air flow over the foil. It makes the wing foil become less weightier on the scale – and hence the weight drop.

The weight drop must equal the lift produced by the foil.
Lift produced, L = .5 x Cl x v^2

Turn the dryer off. As soon as the air flow over the air foil stops, the lift produced is lost and hence the weight reading on the scale goes back to its original reading.

This proves the concept of airfoils producing lift via a simple experiment.
To advance this experiment further, the angle of the air foil can be changed, different types of airfoils can be used and camber and curvature of the foil can also be changed.

I met someone last week who in the course of discussing aviation, mentioned that Laminar Research had come out with an app for iPad. Instantaneous gratification…. It took me all of 5 minutes to download it.

Its a well done app. To bring in a flight model into a small footprint and have it run on a tablet like the iPad is not a small task. Then have it run really well is another thing all together. The app is a leaned down version of the full scale simulator, but even so it retains most of its authenticity in terms of the physics. The model reacts really well on the iPad and is sensitive to movement. The different views are well done and the ability to switch between views is very valuable.

Sound is realistic and instrumentation is adequate.

When there isn’t enough time to start up the full scale simulator, this app absolutely suffices and is not a great addition to the suite. Of course, for flight enthusiasts immersion is never enough and we always seek more!

CPJ

As always, this past month i was at the EAA Air Show in Oshkosh, Wisconsin. Of course everything else was there – the airplanes, the aerobatic events, the product vendors, and LOTs of visitors. The weather cooperated – it was a balmy 86 degrees with a light breeze.

One thing i have noticed change over the years is the number of instances of flight simulators that are present at the show. This season i noticed at least two instances of product vendors using simulators to demonstrate their aircraft.

One of them had a long line of people waiting more for the simulator, rather than truly wanting to see the aircraft itself – but heck, you cant blame those people. For those who dont have easy access to one, it is an attraction that one cant refuse. This one used XPlane as its base and a wide screen setup for visuals.

The seat was my attraction. I wanted to feel how active those seats were. They were actuator driven and USB controlled. The ride was nice. It did reproduce motion well enough. However, what i couldnt tell is whether it did reproduce all six degrees of motion. for those of you who are interested, it was produced by CXC Simulations.

CPJ