One of the many ways to get a plane airborne is to blow fast moving air along the wings, generating lift. The above clipping is the scenario in action during a violent storm.

And surprisingly this method of moving the medium of traverse ( air ) instead of the object itself is the principle of operation of Wind Tunnels.

What is a wind tunnel ?

They are tube shaped facilities where powerful fans move air through the tube. The object is placed ( bolstered ) in a test section and the speeds of the air blown are controlled by fans 

By moving air around an object, the wind tunnel simulates the conditions during operation.

The object can be a smaller-scale model of a vehicle, one piece of a vehicle, a full-size aircraft or spacecraft, or even a common object like a tennis ball.

              NASA Tests Boeing Aircraft Tail in World’s Largest Wind Tunnel  

Usually, the object carries special instruments to measure the forces produced by the air on the object.

Engineers also study how the air moves around the object by injecting smoke or dye into the tunnel and photographing its motion around the object. Improving the flow of air around an object can increase its lift and decrease its drag.

It saves a lot of time and money required for the testing and analysis of designs, and prototypes.


I leave you guys with this clipping from a wind tunnel testing facility at NASA:

The Flappy Plane : This phenomenon is known as Flutter in Aerodynamics. It is an unstable oscillation that can lead to destruction


Have a Great Day!

More about Wind Tunnels: NASA, explainthatstuff

Our Flying Observatory Goes to New Zealand!

Our flying observatory, called SOFIA, carries a 100-inch telescope inside a Boeing 747SP aircraft. Scientists onboard study the life cycle of stars, planets (including Pluto’s atmosphere), the area around black holes and complex molecules in space. 

Heading South

Once each year our flying observatory, SOFIA, its team and instruments travel to the Southern Hemisphere to Christchurch, New Zealand. From there the team studies stars and other objects that cannot be seen while flying in the Northern Hemisphere.

What We Study

We often study star formation in our Milky Way Galaxy. But from the Southern Hemisphere we can also study the lifecycle of stars in two other galaxies called the Magellanic Clouds. The Magallenic Clouds have different materials in them, which changes how stars form in these galaxies. Scientists are studying these differences to better understand how the first stars in our universe formed.  

Home Away from Home

The observatory and its team use the National Science Foundation’s U.S. Antarctic Program facility at Christchurch International Airport. The Antarctic program’s off-season is June and July, so it’s an ideal time for us to use these facilities.

Another Blast of Winter

The Southern Hemisphere’s seasons are opposite from our own. When we are operating from Christchurch in June and July, it’s winter. This means that the nights are very long – ideal for our nighttime observing flights, which last approximately 10 hours.

Light Show

These observations often bring us so far south that the team onboard can see the Southern Lights, also called the Aurora Australis. This is the Southern Hemisphere equivalent of the Northern Lights, or Aurora Borealis, visible near the North Pole. Auroras are caused by particles from space hitting the atmosphere near Earth’s magnetic poles. Our scientists onboard SOFIA don’t study the aurora, but they do enjoy the view.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

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In 1984 NASA Dryden Flight Research Center and the Federal Aviation Administration (FAA) teamed-up in a unique flight experiment called the Controlled Impact Demonstration (CID), to test the impact of a Boeing 720 aircraft using standard fuel with an additive designed to supress fire. The additive FM-9, a high molecular-weight long chain polymer, when blended with Jet-A fuel had demonstrated the capability to inhibit ignition and flame propagation of the released fuel in simulated impact tests.

Antimisting kerosene (AMK) cannot be introduced directly into a gas turbine engine due to several possible problems such as clogging of filters. The AMK must be restored to almost Jet-A before being introduced into the engine for burning. This restoration is called “degradation” and was accomplished on the B-720 using a device called a “degrader”. Each of the four Pratt & Whitney JT3C-7 engines had a “degrader” built and installed by General Electric (G.E) to break down and return the AMK to near Jet-A quality.

In addition to the AMK research the NASA Langley Research Center was involved in a structural loads measurement experiment which included having instrumented dummies filling the seats in the passenger compartment. Before the final flight on December 1, 1984, more then four years of effort passed trying to set-up final impact conditions considered survivable by the FAA. During those years while 14 flights with crews were flown the following major efforts were underway: NASA Dryden developed the remote piloting techniques necessary for the B-720 to fly as a drone aircraft; General Electric installed and tested four degraders (one on each engine); and the FAA refined AMK (blending, testing, and fueling a full size aircraft). The 14 flights had 9 takeoffs, 13 landings and around 69 approaches, to about 150 feet above the prepared crash site, under remote control. These flight were used to introduce AMK one step at a time into some of the fuel tanks and engines while monitoring the performance of the engines. On the final flight (No. 15) with no crew, all fuel tanks were filled with a total of 76,000 pounds of AMK and all engines ran from start-up to impact (the flight time was 9 minutes) on the modified Jet-A.

The CID impact was spectacular with a large fireball enveloping and burning the B-720 aircraft. From the standpoint of AMK the test was a major set-back, but for NASA Langley, the data collected on crashworthiness was deemed successful and just as important.

Photos and text: NASA DFRC

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Junkers G.38 diesel-powered transport/airliner, later upgraded to more conventional gasoline engines, at the time the world’s largest aircraft in service, designed to compete with the Zeppelins.

Only two units build in the late 20′s, one lost in an accident in 1936, while the remaining unit was destroyed in an airfield by RAF aircraft in 1941.