ADTO # 75 - August 20, 1999
PART 1: Upcoming Chats
PART 2: Project News
PART 3: Midway through the Test
Thursday, August 26, at 1:00 p.m. PDT
Practice Chat with Oran Cox
For more info:
Tuesday, September 14, 1999, 12 PM Pacific Time:
Dan Cooper, instrumentation technician
Dan has many responsibilities in the twelve-foot pressure wind
tunnel. He manufactures tables and test equipment, and connnects various
control lines. With the help of a special pressure measuring system, he
also monitors the pressure of the lines and electrical connections.
Additionally, Dan helps assemble wind tunnel test models, and ensures all
test equipment is prepared preoperly for use in the wind tunnel.
Read Dan Cooper's profile prior to joining this chat.
Registration for this chat will begin on August 31.
We are following several aeronautics research projects at NASA Ames
Research Center this summer and will be bringing them to you in the Fall,
stay posted for more news.
- - - - - - -
Follow a Wind Tunnel Test of the Airliner of the Future
Meet the people from NASA who have been planning and working this
Read their compelling field journals as they surmount problems and the
Learn more about High Speed Research.
The model is in the tunnel, and air is about to start blowing. Make a
- - - - - - -
Summer Air Travel Contest
Only 11 days left to submit your entry!! Entries due August 18, 1999.
This a special summer contest for Aerospace Team Online. This contest is
open to all students between the grades of fourth through twelfth.
For this contest, we ask students to help researchers here at NASA solve
the air travel traffic problems. For more information go to
[Editor's Note: Mina Cappuccio is the NASA Ames research engineer on
the low speed test of the High Speed Civil
Transport Technology Concept low speed test of the High Speed Civil Transport
Technology Concept Airplane model. Read her biography at http://quest.arc.nasa.gov/aero/team/cappuccio.html
MIDWAY THROUGH THE TEST
By Mina Cappuccio
August 18, 1999
We began testing the Wing 3 configuration on August 4th. We have obtained
lots of data. We ran Wing 3 with zero flaps and with tails on off. We use
zero flaps as a benchmark to measure our increments from. We tested the
optimum Leading Edge and Trailing Edge configurations based on the TCA-4
test. We ran that with tail on and tail off then we tested it with
different tail angles (stab angles). The tail rotates manually and we can
test different rotation angles.
Then we did a bunch of performance and stability and control (S&C) runs.
Performance runs are always pitch polars with a Beta or sideslip angle set
to zero. A pitch polar means we get data at different angles of attack.
This was done at low and high Q, where Q stands for dynamic pressure. It
directly correlates to Reynolds Numbers (RN). Low Q means low RN and a
high Q means high RN. This part of the test goes back to our test
objectives. Our first objective was to try to figure out what the best
leading edge and trailing edge flap configuration was and to try to figure
out what the Reynolds Number effect is on the best flap configuration.
We also did a bunch of stability and control (S&C) runs. These are usually
Beta sweeps at a constant angle of attack. Or angle of attack sweeps at a
constant beta. These runs look at the lateral and directional stability,
including, pitching moment, rolling moment, and yawing moment.
For the plain flap optimal configuration we did flow visualizations for
three angles of attack. To do this we painted an oil and tempera powder
mixture on the wing and then took pictures of the patterns on the wing
made by the air flow over the oil.
We tested what we thought would be the optimum configuration and then we
started changing the deflection angle of the outboard leading edge. Then
we started playing around with the trailing edge deflection angles to see
if there was an optimum deflection angle. This was an incremental step by
step process where we tried to optimize the flaps. In the end we found
that our estimate of the best outboard leading edge was correct. We also
found a better deflection angle for the inboard leading flaps. This was
one of the new flaps we had built especially for this test. This was good
news. Most of this was tested at low pressure. Then we did more low and
high Reynolds numbers (Q) testing on the best model shape and more tests
with tails on and tails off. Then we did more S&C testing and then we were
done up with the plain flaps.
From our test objectives we had planned to look at three different
configurations: plain, variable camber, and sealed slat to optimize the
shape of the wing at the Leading Edge for different deflection angles.
Next we were planning to do trim runs with the canard, but we skipped that
because we are behind schedule and if we have to cut some of the runs at
the end we might cut these.
Now we are in the middle of the optimization of the variable camber
leading edge flaps. We started this on Friday, August 13, 1999. So far we
have figured out what the best outboard and inboard flaps are and we have
done some flow visualization studies. This information will go to the
CFDer's, computational fluid dynamic researchers. Throughout the test plan
the runs have different researchers in mind. Just this morning we finished
the trailing edge flap study and picked the best trailing edge flap.