PLANNING FOR THE WIND TUNNEL TEST OF THE 1903 WRIGHT FLYER

by Susan Lee

October 16, 1998

I have been able to attend the planning meetings for the upcoming wind
tunnel test and I would like to share some of the concerns and
preparations that are being addressed by the engineers planning for the
test.

In some ways this test is very simple compared to many of the tests done
here at Ames Research Center and that is good because it means a little
less work, but it surprisingly presents several challenges as well.


One concern is that the model is made of wood and cloth. Since the 80' by
120' wind tunnel draws air in from the marshlands of San Francisco Bay,
and since March is frequently rainy, the air in that tunnel might be wet.
Chances are good that the untreated model would get wet and that would
affect the data.  Presently we are planning to hold the test in the 40' by
80' tunnel. This air will be drier and nice for another reason, you don't
have to climb 3 flights of stairs to get there!

Some of you may have seen the photos of the model in the hangar.  Did you
know that this hangar once was the home of a huge dirigible. Since its a
historic hangar, it's a good safe place to keep a bit of history, the
model of the 1903 Wright Flyer. In the photos you can see that there is a
dummy on the model, or did we fool you into thinking that was really
Wilbur Wright?

Do you think the dummy will sit on the model in the wind tunnel? It will.
This will simulate how a person lying on the plane will effect the
airflow. I asked if the dummy weighed as much as a real person
and found out it doesn't. To simulate the weight of a real person Pete
Zell the test engineer told me they would throw a sack of potatoes on the
model. At first I wasn't sure if he was kidding but he was. They will
use some weights that will produce the proper weight for the test.

Since there won't be a real person flying the plane, the engine and the
wings, and the canard and the rudder will have to be controlled remotely.
The AIAA members have built a console that will control them for the test.
They decided to use an electric motor for this model (You know that the
Wright brothers engine was a gasoline engine.)

The instrumentation engineers are trying to plan for this.  They think the
engine might make noise.  Not the kind you hear but the kind that will
effect the data from the test.  At you house if someone runs the blender
or the vacuum does the TV picture get fuzzy? Well that's similar to the
effect the engine might have on the data. Of course they will find a
solution to this problem if they need to.

Meanwhile the balance is in the calibration lab. It will be tested to
make sure its measurements are accurate and can be used at the most
extreme measurements that will be taken. When they take the Wright Flyer
back off the sting, they will remove the sensors that will be used
to make measurements during the test. These will be calibrated too.

I hope to share more with you about the preparations going on. The
engineers and researchers working on this job have signed up because
of their interest but in the meanwhile they are all working on four or
five other projects. When they are too busy to share some of their stories
I'll do my best to fill in.