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Chapter 19: “Zoom and Boom!”
September 2006

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It was November 4, 1998, and I had arrived at Ellington Field in Houston, Texas, for my very first flight in the T-38 training jet. My instructor pilot Andy Roberts was finishing a phone call when I arrived in his office. I heard him say, in part as he ended the call, “…gotta go; I’m giving a ‘zoom and boom’ ride to one of the new ASCANs (astronaut candidates).” Hmmm…talk about anxiety!

NASA astronauts use the T-38 to perform “spaceflight readiness training” which is another way to say that we fly the jets to hone our skills of cockpit teamwork and decision making. These sleek looking white jets, painted in blue trim with the NASA logo, are a two-engine Air Force trainer that has been upgraded with state-of-the-art electronics specifically for NASA and the astronauts to enhance its safety characteristics. You see, things happen very quickly in the jet, similarly to how things go on a space shuttle liftoff and ascent into space.

On this day I was being introduced to the jet and all of its capabilities. One of those is “pulling g’s.” In the T-38, which can fly at speeds of up to 700 knots (nautical miles/hour), it’s quite easy to “…pull a g”; another way to say you are experiencing the force of gravity. On Earth we experience one g every day just walking around. Our weight is simply a calculation of the force of gravity (“g”) multiplied by our body mass. In the T-38, we just crank up the speed and pull the stick back or bank hard to the right or left. Our weight will increase proportionately with each g and we can safely get to five or six total g’s! Pulling g’s is another training exercise for us; we use this aircraft capability to help us adapt to the feelings and sensations (including disorientation and nausea!) we may experience during spaceflight; especially when we hit “zero g” (weightlessness) once our engines shut down. A typical shuttle ascent or entry “pulls” two to three times your weight in g-forces. The Russian Soyuz vehicle is similar in that the typical g load is around three, yet there are subtle differences. If the Soyuz has an “off-nominal (not normal)” entry, it is possible that you will pull eight g’s, although for a shorter period of time. Another difference is that in the Soyuz your flight orientation is such that the force is always through your chest because you fly on your back. The shuttle is the same for launch, but different for entry when you are sitting in an upright position.

During a trip to Star City last summer, I did my first runs in their centrifuge trainers. They have two; one with a short arm (four meters) and one with a long arm (eight meters). My first “spin” in the small centrifuge was a simple one. Crank it up to four g’s, then slow down, stop for a five- minute rest, then crank up to eight! Let me tell you that breathing was not a simple task with 1,600 pounds of force sitting on my chest (eight times Clay’s weight equals about 1,600 pounds)! The Russian support staff said it’s like hugging a big grandmother! I’ll say! I wouldn’t want to meet her in a dark alley! The second run, a few days later, consisted of flying the actual gravity profile for a standard Soyuz re-entry. Upon interfacing with the Earth’s atmosphere, the g-force climbs to around four. If the Soyuz guidance was to fail and an emergency descent/ballistic entry (essentially falling like a rock) were required, then it could ramp up to between eight and 12 g’s. I considered it a “walk in the park” after hugging granny!

Our November 1998 flight in the T-38 ended uneventfully. We performed barrel rolls, loop-to-loops, aileron rolls and we even broke the sound barrier (although we had to fly up to 40,000 feet and fly straight down to the Gulf of Mexico to do it!). As I calmly hit the showers and dressed for the trip home, I felt that I had indeed accomplished something special; my first flight and I didn’t throw up. As I exited the locker room and passed through the silent hangar filled with T-38’s parked in tight formation, my eyes rested upon the sight of an open trash can. At that moment, my previously anointed self-confidence departed as my brain cells kicked in. My “zoom and boom” had become the “whirl and hurl!!!” See you next time!