fganger
01-25-2006, 07:53 PM
A friend of mine e-mailed this to me, I found it quite interesting.
Opps, I just found out we have a limit on the amount of text we can post at one time. I'm breaking this report up into 2 parts.
Frank
High Flight
By Barry Schiff
Maj. Dean Neeley is in the forward, lower cockpit of the Lockheed U-2ST, a two-place version of the U-2S, a high-altitude reconnaissance aircraft that the Air Force calls "Dragon Lady." His voice on the intercom breaks the silence. "Do you know that you're the highest person in the world?" He explains that I am in the higher of the two cockpits and that there are no other U-2s airborne right now. "Astronauts don't count," he says, "They're out of this world."
We are above 70,000 feet and still climbing slowly as the aircraft becomes lighter. The throttle has been at its mechanical limit since takeoff, and the single General Electric F118-GE-101 turbofan engine sips fuel so slowly at this altitude that consumption is less than when idling on the ground. Although true airspeed is that of a typical jetliner, indicated airspeed registers only in double digits.
I cannot detect the curvature of the Earth, although some U-2 pilots claim that they can. The sky at the horizon is hazy white but transitions to midnight blue at our zenith. It seems that if we were much higher, the sky would become black enough to see stars at noon. The Sierra Nevada, the mountainous spine of California, has lost its glory, a mere corrugation on the Earth. Lake Tahoe looks like a fishing hole, and rivers have become rivulets. Far below, "high flying" jetliners etch contrails over Reno, Nevada, but we are so high above these aircraft that they cannot be seen.
I feel mild concern about the bailout light on the instrument panel and pray that Neeley does not have reason to turn it on. At this altitude I also feel a sense of insignificance and isolation; earthly concerns seem trivial. This flight is an epiphany, a life-altering experience. I cannot detect air noise through the helmet of my pressure suit. I hear only my own breathing, the hum of avionics through my headset and, inexplicably, an occasional, shallow moan from the engine, as if it were gasping for air. Atmospheric pressure is only an inch of mercury, less than 4 percent of sea-level pressure. Air density and engine power are similarly low. The stratospheric wind is predictably light, from the southwest at 5 kt, and the outside air temperature is minus 61 degrees Celsius. Neeley says that he has never experienced weather that could not be topped in a U-2, and I am reminded of the classic transmission made by John Glenn during Earth orbit in a Mercury space capsule: "Another thousand feet, and we'll be on top."
Although not required, we remain in contact with Oakland Center while in the Class E airspace that begins at Flight Level 600. The U-2's Mode C transponder, however, can indicate no higher than FL600. When other U-2s are in the area, pilots report their altitudes, and ATC keeps them separated by 5,000 feet and 10 miles. Our high-flying living quarters are pressurized to 29,500 feet, but 100-percent oxygen supplied only to our faces lowers our physiological altitude to about 8,000 feet. A pressurization-system failure would cause our suits to instantly inflate to maintain a pressure altitude of 35,000 feet, and the flow of pure oxygen would provide a physiological altitude of
10,000 feet.
The forward and aft cockpits are configured almost identically. A significant difference is the down-looking periscope/driftmeter in the center of the forward instrument panel. It is used to precisely track over specific ground points during reconnaissance, something that otherwise would be impossible from high altitude. The forward cockpit also is equipped with a small side-view mirror extending into the air stream. It is used to determine if the U-2 is generating a telltale contrail when over hostile territory. Considering its 103- foot wingspan and resultant roll dampening, the U-2 maneuvers surprisingly well at altitude; the controls are light and nicely harmonized. Control wheels (not sticks) are used, however, perhaps because aileron forces are heavy at low altitude. A yaw string (like those used on sailplanes above each canopy silently admonishes those who allow the aircraft to slip or skid when maneuvering. The U-2 is very much a stick-and-rudder airplane, and I discover that slipping can be avoided by leading turn entry and recovery with slight rudder pressure.
When approaching its service ceiling, the U-2's maximum speed is little more than its minimum. This marginal difference between the onset of stall buffet and Mach buffet is known as coffin corner, an area warranting caution. A stall/spin sequence can cause control loss from which recovery might not be possible when so high, and an excessive Mach number can compromise structural integrity. Thankfully, an autopilot with Mach hold is provided. The U-2 has a fuel capacity of 2,915 gallons of thermally stable jet fuel distributed among four wing tanks. It is unusual to discuss turbine fuel in gallons instead of pounds, but the 1950s-style fuel gauges in the U-2 indicate in gallons. Most of the other flight instruments seem equally antiquated.
I train at 'The Ranch' Preparation for my high flight began the day before at Beale Air Force Base (a.k.a. The Ranch), which is north of Sacramento, California, and was where German prisoners of war were interned during World War II. It is home to the 9th Reconnaissance Wing, which is responsible for worldwide U-2 operations, including those aircraft based in Cyprus; Italy; Saudi Arabia; and South Korea.
After passing a physical exam (whew!), I took a short, intensive course in high-altitude physiology and use of the pressure suit. The 27-pound Model S1034 "pilot's protective assembly" is manufactured by David Clark (the headset people) and is the same as the one used by astronauts during shuttle launch and reentry. After being measured for my $150,000 spacesuit, I spent an hour in the egress trainer. It provided no comfort to learn that pulling up mightily on the handle between my legs would activate the ejection seat at any altitude or airspeed. When the handle is pulled, the control wheels go fully forward, explosives dispose of the canopy, cables attached to spurs on your boots pull your feet aft, and you are rocketed into space. You could then free fall in your inflated pressure suit for 54,000 feet or more. I was told that "the parachute opens automatically at 16,500 feet, or you get a refund."
I later donned a harness and virtual-reality goggles to practice steering a parachute to landing. After lunch, a crew assisted me into a pressure suit in preparation for my visit to the altitude chamber. There I became reacquainted with the effects of hypoxia and was subjected to a sudden decompression that elevated the chamber to 73,000 feet. The pressure suit inflated as advertised and just as suddenly I became the Michelin man. I was told that it is possible to fly the U-2 while puffed up but that it is difficult.
A beaker of water in the chamber boiled furiously to demonstrate what would happen to my blood if I were exposed without protection to ambient pressure above 63,000 feet. After a thorough preflight briefing the next morning, Neeley and I put on long johns and UCDs (urinary collection devices), were assisted into our pressure suits, performed a leak check (both kinds), and settled into a pair of reclining lounge chairs for an hour of breathing pure oxygen. This displaces nitrogen in the blood to prevent decompression sickness (the bends) that could occur during ascent. During this "pre-breathing," I felt as though I were in a Ziploc bag- style cocoon and anticipated the possibility of claustrophobia. There was none, and I soon became comfortably acclimatized to my confinement.
Opps, I just found out we have a limit on the amount of text we can post at one time. I'm breaking this report up into 2 parts.
Frank
High Flight
By Barry Schiff
Maj. Dean Neeley is in the forward, lower cockpit of the Lockheed U-2ST, a two-place version of the U-2S, a high-altitude reconnaissance aircraft that the Air Force calls "Dragon Lady." His voice on the intercom breaks the silence. "Do you know that you're the highest person in the world?" He explains that I am in the higher of the two cockpits and that there are no other U-2s airborne right now. "Astronauts don't count," he says, "They're out of this world."
We are above 70,000 feet and still climbing slowly as the aircraft becomes lighter. The throttle has been at its mechanical limit since takeoff, and the single General Electric F118-GE-101 turbofan engine sips fuel so slowly at this altitude that consumption is less than when idling on the ground. Although true airspeed is that of a typical jetliner, indicated airspeed registers only in double digits.
I cannot detect the curvature of the Earth, although some U-2 pilots claim that they can. The sky at the horizon is hazy white but transitions to midnight blue at our zenith. It seems that if we were much higher, the sky would become black enough to see stars at noon. The Sierra Nevada, the mountainous spine of California, has lost its glory, a mere corrugation on the Earth. Lake Tahoe looks like a fishing hole, and rivers have become rivulets. Far below, "high flying" jetliners etch contrails over Reno, Nevada, but we are so high above these aircraft that they cannot be seen.
I feel mild concern about the bailout light on the instrument panel and pray that Neeley does not have reason to turn it on. At this altitude I also feel a sense of insignificance and isolation; earthly concerns seem trivial. This flight is an epiphany, a life-altering experience. I cannot detect air noise through the helmet of my pressure suit. I hear only my own breathing, the hum of avionics through my headset and, inexplicably, an occasional, shallow moan from the engine, as if it were gasping for air. Atmospheric pressure is only an inch of mercury, less than 4 percent of sea-level pressure. Air density and engine power are similarly low. The stratospheric wind is predictably light, from the southwest at 5 kt, and the outside air temperature is minus 61 degrees Celsius. Neeley says that he has never experienced weather that could not be topped in a U-2, and I am reminded of the classic transmission made by John Glenn during Earth orbit in a Mercury space capsule: "Another thousand feet, and we'll be on top."
Although not required, we remain in contact with Oakland Center while in the Class E airspace that begins at Flight Level 600. The U-2's Mode C transponder, however, can indicate no higher than FL600. When other U-2s are in the area, pilots report their altitudes, and ATC keeps them separated by 5,000 feet and 10 miles. Our high-flying living quarters are pressurized to 29,500 feet, but 100-percent oxygen supplied only to our faces lowers our physiological altitude to about 8,000 feet. A pressurization-system failure would cause our suits to instantly inflate to maintain a pressure altitude of 35,000 feet, and the flow of pure oxygen would provide a physiological altitude of
10,000 feet.
The forward and aft cockpits are configured almost identically. A significant difference is the down-looking periscope/driftmeter in the center of the forward instrument panel. It is used to precisely track over specific ground points during reconnaissance, something that otherwise would be impossible from high altitude. The forward cockpit also is equipped with a small side-view mirror extending into the air stream. It is used to determine if the U-2 is generating a telltale contrail when over hostile territory. Considering its 103- foot wingspan and resultant roll dampening, the U-2 maneuvers surprisingly well at altitude; the controls are light and nicely harmonized. Control wheels (not sticks) are used, however, perhaps because aileron forces are heavy at low altitude. A yaw string (like those used on sailplanes above each canopy silently admonishes those who allow the aircraft to slip or skid when maneuvering. The U-2 is very much a stick-and-rudder airplane, and I discover that slipping can be avoided by leading turn entry and recovery with slight rudder pressure.
When approaching its service ceiling, the U-2's maximum speed is little more than its minimum. This marginal difference between the onset of stall buffet and Mach buffet is known as coffin corner, an area warranting caution. A stall/spin sequence can cause control loss from which recovery might not be possible when so high, and an excessive Mach number can compromise structural integrity. Thankfully, an autopilot with Mach hold is provided. The U-2 has a fuel capacity of 2,915 gallons of thermally stable jet fuel distributed among four wing tanks. It is unusual to discuss turbine fuel in gallons instead of pounds, but the 1950s-style fuel gauges in the U-2 indicate in gallons. Most of the other flight instruments seem equally antiquated.
I train at 'The Ranch' Preparation for my high flight began the day before at Beale Air Force Base (a.k.a. The Ranch), which is north of Sacramento, California, and was where German prisoners of war were interned during World War II. It is home to the 9th Reconnaissance Wing, which is responsible for worldwide U-2 operations, including those aircraft based in Cyprus; Italy; Saudi Arabia; and South Korea.
After passing a physical exam (whew!), I took a short, intensive course in high-altitude physiology and use of the pressure suit. The 27-pound Model S1034 "pilot's protective assembly" is manufactured by David Clark (the headset people) and is the same as the one used by astronauts during shuttle launch and reentry. After being measured for my $150,000 spacesuit, I spent an hour in the egress trainer. It provided no comfort to learn that pulling up mightily on the handle between my legs would activate the ejection seat at any altitude or airspeed. When the handle is pulled, the control wheels go fully forward, explosives dispose of the canopy, cables attached to spurs on your boots pull your feet aft, and you are rocketed into space. You could then free fall in your inflated pressure suit for 54,000 feet or more. I was told that "the parachute opens automatically at 16,500 feet, or you get a refund."
I later donned a harness and virtual-reality goggles to practice steering a parachute to landing. After lunch, a crew assisted me into a pressure suit in preparation for my visit to the altitude chamber. There I became reacquainted with the effects of hypoxia and was subjected to a sudden decompression that elevated the chamber to 73,000 feet. The pressure suit inflated as advertised and just as suddenly I became the Michelin man. I was told that it is possible to fly the U-2 while puffed up but that it is difficult.
A beaker of water in the chamber boiled furiously to demonstrate what would happen to my blood if I were exposed without protection to ambient pressure above 63,000 feet. After a thorough preflight briefing the next morning, Neeley and I put on long johns and UCDs (urinary collection devices), were assisted into our pressure suits, performed a leak check (both kinds), and settled into a pair of reclining lounge chairs for an hour of breathing pure oxygen. This displaces nitrogen in the blood to prevent decompression sickness (the bends) that could occur during ascent. During this "pre-breathing," I felt as though I were in a Ziploc bag- style cocoon and anticipated the possibility of claustrophobia. There was none, and I soon became comfortably acclimatized to my confinement.