After the Test - Final thoughtsby Fanny Zuniga
March 25, 1988
Looking back now on my Supersonic Transport wind tunnel test, I have some final thoughts to share with you. I want to describe what we did after the test to wrap things up, what we learned, and why we ran this test.
We spent the first few weeks after the test checking over all of the data that was stored on the computer. There are a bunch of corrections we make to the data, and we go through all the data to make sure the corrections were made properly. An example of this is correcting the airplane aerodynamic loads to remove the effect of the wind tunnel walls. Normally, air flows freely around an object, such as an airplane. In a wind tunnel, the walls block some of the flow that tries to go around the model which gives a slightly different effect than in free air. For this reason, we calculate the effect of the walls and adjust the measured forces so that they more accurately represent what would happen in free air.
Now that we've checked all the data, we post it on the internet! We do this because there are researchers all over the country studying the data from this model. Sorry, you can't go look at this data because we don't want our results available to the whole world. Our data is sensitive and I cannot freely share our specific results with you and the general public. We are only allowed to share our data and knowledge with the other members of our High-Speed Research program. The members include NASA and several U.S. airplane and engine companies. This program is necessary because developing an airplane like this is a huge investment for any one company to undergo alone. The program members have agreed to protect the data so our U.S. companies will be given the competitive edge they need to build this supersonic airliner. This will also help ensure the U.S. aerospace industry remain competitive and prosperous in the world market. This will in return help the U.S. create jobs and boost our economy.
We will study this data to learn as much about this model as possible and help us continue to improve our design and meet our project goals. A lot of what we learned is already being used in planning the next test with this model. One of the things we've learned from this test are which flaps on the wings give us the best performance at takeoff and landing conditions. Flaps are real important because they have a real impact on noise, fuel usage, and most importantly airplane weight. We also learned the effectiveness of the control surfaces (horizontal tail, rudder, and ailerons) to make sure this kind of aircraft can be flown safely. Basically, we will continue to test and study this airplane to convince ourselves that we can build one that is safe, affordable, and environmentally friendly. Hopefully, if we are successful in our endeavors, affordable supersonic travel and cargo delivery will be available early in the next century.
Finally, since we are users of the wind tunnel, we spent some time giving feedback to the people that run the tunnel. For example, we recommended some important changes and additions to the data plotting program which would make it more useful for future research staff. We also spent some time telling the wind-tunnel managers what we thought worked well and what we thought needed some improvement. We are part of the process for improving wind tunnel tests in the future. If you want to improve something, you have to talk to the people that use it.
I hope you have enjoyed learning about my wind tunnel test. As for me, I have already started getting ready for the next test of this model. This model will be modified some now and will be tested again at NASA-Langley in their 14x22 ft. wind tunnel. We have to modify the model to keep up with the current design of this airplane and also to refurbish any parts that may be worn. There's never a dull moment when you're racing to complete the design of the next supersonic airplane.
You can see some more pictures of our model, the wind tunnel, and the crew that made this test happen.