High-Altitude Research
a Thrill for
Aerospace Corporation Engineer
By Dave Gutierrez
EL SEGUNDO, Calif. (2/16/99) -- I grew up with the space program. The sky has always been an inspiring place to me. The love of space brought me to The Aerospace Corporation, where I've spent 11 years designing, building and deploying science experiments.
My involvement for the last two years in the development of an infrared system called SHARP, the SEBASS High-Altitude Research Project, landed me in a unique and challenging assignment last year as a payload specialist on NASA's high-altitude research aircraft, the WB-57. It was the culmination of a childhood dream.
The vehicle holds two crew members: the pilot and the payload specialist. I began training last March for my role as "backseater" on this unique aircraft, performs upper-atmospheric sampling and Earth reconnaissance.
Survival Course
After receiving an extensive physical examination at NASA's Johnson Space Center in Houston, I headed for the Naval Air Station in Pensacola, Fla., for a four-day water survival course.
The training covered all aspects of sea survival, from aircraft ejection and water landings under a parachute to rescue and recovery operations. I swam 75 yards in flight gear, was shot from an ejection seat in a simulator, and was hoisted by a helicopter from open water. The training culminated in two parasail rides, each followed by an open-water landing, requiring me to use the skills I'd learned during the course.
I underwent physiology training for low- and high-altitude flight at Edwards Air Force Base, where I experienced five hypobaric chamber rides which demonstrated the effects of hypoxia (lack of oxygen) and pressure changes on the body.
Painful bloating can occur at altitude pressures above 40,000 feet. The training teaches subjects how the body reacts to hypoxia and how to respond quickly should it occur.
Pressure Suit
High-altitude flight--above 50,000 feet--requires the use of a fully pressurized flight suit. The suits are similar to those worn by pilots aboard the SR-71 Blackbird and the space shuttle during ascent. At Edwards I was fitted for my own suit and received the requisite training.
I underwent another round of water training, this time in the pressure suit. The highlight was a hypobaric chamber ride to a pressure altitude of more than 100,000 feet (20 miles). The suit inflates to keep pressure around the body at about 35,000 feet, a good compromise for breathing pure oxygen and the lack of mobility caused by the stiffness of the suit.
While passing through 60,000 feet, water in a small jar placed inside the chamber began boiling. This is Armstrong's Line, the point at which bodily fluids would begin vaporizing if no suit were worn.
I had always wondered what it would be like to wear a space suit. It is pretty confining, and if you are at all claustrophobic, it's stressful. Other than radio chatter, you hear only your heart beating and the sound of oxygen flowing into the helmet during each breath.
The suits are cooled and heated with conditioned air supplied by the vehicle. It is normal, however, to experience wide temperature variations during suitup, taxi and takeoff as well as during the mission itself. Current mission scenarios require the suits to be worn for up to seven hours. They are outfitted with eating and drinking ports and yes, bathroom facilities.
Ground School, Flight Training
I spent a week in Houston last July for ground school and flight training in the aircraft. My instructor was NASA pilot Steve Feaster, who has logged thousands of hours in this type of aircraft.
I spent the first part of the week learning about the craft's systems and familiarizing myself with the cockpit. The backseat area is small, roughly the size of a coach seat on a commercial airliner. My primary responsibilities would be programming the Inertial Navigation System (INS) and reading checklists to the pilot. My main duties would be operating and evaluating the SHARP sensor and the special tracking system on which it is mounted.
After programming the INS for a trip over the Gulf of Mexico toward Corpus Christi, we took off on my first flight.
The aircraft accelerates quickly and climbs at an amazing rate. We leveled off just below 50,000 feet and practiced several emergency scenarios. After a few hours in the air we returned for several touch-and-go landings before completing the flight.
The next morning we suited up with full pressure suits for a high-altitude flight. I was anxious but realized this would probably be my best opportunity to relax and enjoy the view, not yet having to concentrate on operating the SHARP sensor.
Curvature of Earth Visible
On this flight we reached 63,000 feet. The curvature of the Earth was visible. With more than 96 percent of the atmosphere below us, the top of the troposphere was visible as a bluish-white arc on the horizon. The sky above was dark, like a normal sky about 30 to 40 minutes after sunset.
My final flight was a checkout ride to 50,000 feet, where I applied all of the skills I had learned during my week of training. We simulated engine loss scenarios, hydraulic failures and midcourse reprogramming of the INS. I successfully completed the flight, earning qualification as a NASA crew member and backseater for the WB-57.
The SHARP project has now entered the flight test phase. I have flown with the system twelve times, accumulating about 40 hours in the aircraft. The aircraft operations are becoming more natural, allowing me to focus on evaluating sensor performance and troubleshooting anomalies.
During my last flight in November our team collected longwave infrared hyperspectral data on more than 90 percent of the targets deployed during flight tests at Eglin Air Force Base in Florida. Aerospace engineers Brad Johnson and Steve Hansel were instrumental in the successful integration of the sensor during this first series of flights.
This has been the experience of a lifetime, and I'm looking forward to future flights with SHARP aboard the WB-57.
