by Marcia Gitelman
Approximately twenty percent of the United States astronauts are women. In the history of the program only three women have been designated as pilot astronauts. On October 11, 2000 Lt. Col. Pamela Ann Melroy USAF, after a two-year delay, became the third woman to make her “rookie” flight into space as pilot on the orbiter Discovery.
Her primary responsibility was keeping the shuttle systems working perfectly and helping Commander Brian Duffy fly the rendezvous with the International Space Station. On landing she monitored all procedures and deployed the landing gear and the drag chute.
This mission was a critical step in the series of flights designated as assembly flights of the ISS. It carried the Z1 truss, on which the solar panels that power the station will be mounted on a later flight, and the Pressurized Mating Adapter (PMA) which will function as a second docking port for vehicles coming in from earth. Installation of both components used for the first time a common berthing mechanism (CPM) which was controlled through a laptop computer. Operating the laptop was the major additional task assigned to Pam.
How does a young woman, raised in Rochester, New York, achieve the lofty goal that puts her in the public eye on a high profile mission? Pam, by her own admission, looks like someone’s “kid sister.” But don’t let that profile fool you! Behind that “kid sister” exterior is a focused military officer whose goal since the age of nine was to become an astronaut.
Pam’s folks were the type of parents who always encouraged their children to do whatever they wanted do. There was no gender bias as they raised their daughter and two sons. Her dad had an amateur interest in astronomy, and Pam remembers the family watching the Apollo 11 landing on the moon.
From that time, the youngster who was always interested in science had a singular vision. When the time came to attend college, she determined that Wellesley would be the best place for her. To help with the tuition she accepted an Air Force ROTC scholarship. She received a Bachelor’s degree in physics and astronomy in 1983 and went on to MIT where she received a Master of Science in earth and planetary sciences in 1984.
Her original intentions were to become a scientist astronaut. When the Air Force proposed that she become a pilot she agreed. She showed up at Air Force Jet Pilot training never having flown an airplane before. “And I loved it. It was a blast! I was very fortunate that in this goal of wanting to be an astronaut, I found all these things that were so much fun.” She flew the KC-10 (the military version of the DC-10) for six years as co-pilot, aircraft commander and instructor pilot. Pam is a veteran of Desert Shield/ Desert Storm with over 200 combat and combat support hours.
In June 1991 she attended Air Force Test Pilot School, and upon graduation she was assigned to C-17 Combined Test Force where she was a test pilot until entering the astronaut program in 1994. She has logged over 4,000 hours flight time in 45 different aircraft.
Learning to fly the shuttle takes place in both ground based and aircraft simulators. Space training is done at the Johnson Space Center in Houston in NASA’s full motion orbiter simulator, which is equipped with a realistic visual system. In space, because of micro-gravity, the orbiter can assume any attitude without regard to its flight path. Normal aerodynamic controls are ineffective. Stick inputs are translated by computers. Orientation is obtained by firing a combination of small rockets or thrusters that control roll, pitch and yaw. In preparation for landing, the orbiter is turned tail first, and two thrusters are fired for two to three minutes to reduce the speed so that gravity can take over. Actual parameters for landing will vary depending on the mission profile and the orbiter weight.
The orbiter begins an initially gradual descent. Thirty-two minutes prior to landing airspeed is 14,800 kts (having decreased from 17,500 kts), and the sink rate is 30,000 feet per minute. The thrusters are now used to turn the shuttle and establish an angle of attack of 40 degrees. The angle at which it enters the atmosphere is critical. Too steep an angle and the orbiter will skip like a stone off the top of the atmosphere. Too shallow an angle will cause excessive speed and frictional heating that could damage the leading edges of the wings. Aerodynamically the orbiter now becomes a glider with normal flight control responses. An autopilot normally controls descent from orbit with the commander and pilot monitoring. The commander usually takes over manually at Mach 1.
An aircraft simulator is used to learn to land the shuttle. It is a modified Grumman Gulfstream II business jet. Its flaps deflect upward to spill lift as well as downward to increase lift. Inside, the normal flight controls have been moved to the right side. The left side has a complete set of space shuttle controls and instruments installed. Both seat positions have Head Up Display. A computer in the main cabin runs the simulation. In flight, when the shuttle training aircraft (STA) reaches 35,000 feet and is abeam the point of intended landing, the instructor pilot drops the main gear, selects reverse thrust and activates simulation mode. This activates the astronaut’s controls. The astronaut navigates the STA around a heading alignment circle.
A normal performance would decrease altitude to 20,000 feet agl and put it at an airspeed of 280 knots at a distance of 15 miles from the intended touchdown target. The STA then would roll out on a high final at 12,000 feet agl and 7 miles from touchdown. At this point the astronaut pushes over the nose to increase the airspeed to 300 kts and to intercept a 20 degree dive angle. At 1,750 feet agl the astronaut executes a pullout to intercept a 3-degree inner glideslope. Shuttle gear is simulated down at 300 feet agl.
The astronaut continues the approach flaring as would be done on the shuttle. If the landing speed is correct, a green light on the panel indicates touchdown when the astronaut’s eyes are 32 feet above the runway. The instructor pilot deselects the simulation mode, normal power is restored, and a manual go-around is executed. Every commander has practiced at least 900 landings in this manner.
The pilot does exactly the same training as the commander. “From the moment you are assigned you are ‘joined at the hip.’ Everywhere you go, anything you do, the other person does it too.
And so, I do the ground based training, here in Houston and at Ames Research Center in California. I also fly the shuttle training aircraft. When we fly, usually out of El Paso, Brian [the commander] gets into one STA and I get in the other one, and we go out together to the range. We have exactly the same weather conditions, and we debrief when we come back. He says ‘how’s your flight?’ I show him the printouts from my missions, show him how I flew, where I landed each time, and we discuss it together. I definitely feel very confident that if I ever had to do it, it would be like landing any other airplane.” Pam has simulated between 500 and 1,000 landings in the shuttle training aircraft.
The fact that STS-92 was the first use in space of the common berthing mechanism (CPM) made this an extraordinary mission. Construction of the station is truly a team effort. “As a test pilot I have seen the entire team from the contractors, Boeing and Allied, and NASA engineers, to the astronauts on this flight. All have worked together testing and getting ready. The system is extremely important to the future of the space station. It makes sense, if we’re doing assembly we’ve got to build pieces, then we’ve got to bring them upstairs, and then attach them. The process of attaching the Z1 Truss and the PMA3 to the Unity module is kind of an interesting little ballet between the robotic arm operator who has to get the pieces and the space station close together, and the berthing mechanism operator who on a laptop computer will be driving a series of four latches which reach out from the inside and grab the pieces and cinch them down. Once there is a good hold on the element, the CPM operator commands 16 bolts in a ring to drive and really bring it in so that it’s tight enough to hold pressure.”
On this flight Pam operated the berthing mechanism and Japanese astronaut Koichi Wakata operated the robotic arm. “I am treating it like the first flight of a new airplane,” said Pam in an interview before the flight. “What you do in that situation is, you do as much testing and engineering analysis as you possibly can on the ground, you dream up every scenario where something could go wrong. My hedge against all this is to try to understand the systems intimately. Right now you have to get pretty deep to stump me. I’ve asked my instructor to give me one scenario a week where he sends me a computer screen shot and says, “What happened, how are you going to fix it?’ And it’s fun. I kind of treat it like a puzzle, like okay, let me go try to figure out how to fix it and what the implications are for down the road. Sometimes computer models can’t completely keep up with some of the strange scenarios that we like to dream up, so we have to table-top them. What are we going to do? We have a lot of redundancy in the system. There are about 70 pages worth of mal procedures in case any conceivable thing goes wrong.”
When you stop to investigate why there are only three women with the pilot designation, you find that test pilot experience is an essential requirement. This is the very same requirement that originally kept women out of the space program. Now that this has been relaxed for the scientist astronauts, you might be tempted to think that it should be relaxed for the pilots as well. However, examining the duties of the various astronaut positions and correlating this with the “mind set” that comes from test pilot experience, a convincing case for the requirement exists.
The good news is that as more women enter the military as pilots, more women will attend Test Pilot School and be eligible for the pilot designation. In the meantime Pam serves as a role model for women and girls as to what they can achieve. “When I go out to talk to schools I see that the doors are really starting to open.”
The one message that she wants to get out to people is, “Just don’t quit; if it’s really what’s in your heart, don’t quit. There were lots of opportunities when I thought that I had maybe bitten off a little bit more than I could chew, but I just didn’t quit, and so that’s why I’m here more than anything else. There’s nothing special about me. I just never stop trying. And so that’s how I achieve my goals. It won’t be that big a deal in a few years. But for now if someone looks at me and says, “Well if she can do it, I can do it,” then I’m happy about that.”
The future holds great promise for Pam. On the “radar screen” will be another flight as pilot, and then the opportunity to become a commander. This normally would take about four to five years. Since military pilots have to “retire” early, Pam still has thoughts of obtaining her Ph.D. Meanwhile we can think of her as someone’s “kid sister,” having fun and contributing in a major way to the betterment of mankind through the vehicle of space flight and exploration.