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Other factors will affect the accuracy of GPS receivers. One of these is that the speed of light varies as it goes through the atmosphere. This might result in a receiver error of up to 12 feet. The clock error alone might add up to 2 feet. Built-in receiver errors might come to another 4 feet. The worst case satellite selection errors might add up to another 25 feet, and the ephemeris error will result in 2 more feet. AU of this adds up to somewhere between 10 and 30 feet of error. One other error has until recently prevented GPS from being used for precision IFR approaches: selective availability (SA). Two frequencies are used by the satellites. The precision code (P-code) is used by military and the course acquisition code (C/A code) is used by the public. The military can arbi trarily induce an error into the C/A – code, which can impart an error of up to 300 feet with out the user being aware of it. Naturally, an error of this magnitude would prevent the pilot from using GPSs for a precision approach. To overcome this, ground stations are being provided that know their position precisely. This ground station will then derive its own GPS position, recognize any error, and then transmit that difference to the user＇s receiver so that the receiver’s computer will then be able to give a precise location with repeatable accuracy of within 3-10 meters (roughly 10-30 feet.) This is called differential GPS (DGPS). It is this precision that is enabling aircraft to make fully-occupied autopilots landings, and which, someday, will make all other types of navigation obsolete. ARNAV Systems, Inc. has two types of GPS receivers available. The first type uses a separate receiver (GPS-506) that interfaces with the FMS-5000 or R-5000 receiver. This combination will provide the pilot with either a loran or GPS position, whichever signal is deemed most accurate. The pilot can also manually select either mode of navigation. The three-dimensional accuracy in the GPS mode (without SA) is within 15 meters horizontally and 90 feet vertically. The second GPS available from ARNAV is the pure GPS receiver, the STAR 5000. The only physical difference between this receiver and the FMS-5000 is appar ently the name on the lower right hand side, the letters GPS on the upper left hand side, and the absence of the XP light on the STAR 5000.2.GPS has been prevented from being used for precision IFR approach just because of （ ）.
Other factors will affect the accuracy of GPS receivers. One of these is that the speed of light varies as it goes through the atmosphere. This might result in a receiver error of up to 12 feet. The clock error alone might add up to 2 feet. Built-in receiver errors might come to another 4 feet. The worst case satellite selection errors might add up to another 25 feet, and the ephemeris error will result in 2 more feet. AU of this adds up to somewhere between 10 and 30 feet of error. One other error has until recently prevented GPS from being used for precision IFR approaches: selective availability (SA). Two frequencies are used by the satellites. The precision code (P-code) is used by military and the course acquisition code (C/A code) is used by the public. The military can arbi trarily induce an error into the C/A – code, which can impart an error of up to 300 feet with out the user being aware of it. Naturally, an error of this magnitude would prevent the pilot from using GPSs for a precision approach. To overcome this, ground stations are being provided that know their position precisely. This ground station will then derive its own GPS position, recognize any error, and then transmit that difference to the user＇s receiver so that the receiver’s computer will then be able to give a precise location with repeatable accuracy of within 3-10 meters (roughly 10-30 feet.) This is called differential GPS (DGPS). It is this precision that is enabling aircraft to make fully-occupied autopilots landings, and which, someday, will make all other types of navigation obsolete. ARNAV Systems, Inc. has two types of GPS receivers available. The first type uses a separate receiver (GPS-506) that interfaces with the FMS-5000 or R-5000 receiver. This combination will provide the pilot with either a loran or GPS position, whichever signal is deemed most accurate. The pilot can also manually select either mode of navigation. The three-dimensional accuracy in the GPS mode (without SA) is within 15 meters horizontally and 90 feet vertically. The second GPS available from ARNAV is the pure GPS receiver, the STAR 5000. The only physical difference between this receiver and the FMS-5000 is appar ently the name on the lower right hand side, the letters GPS on the upper left hand side, and the absence of the XP light on the STAR 5000.1.With respect to all the factors, the GPS error might be （ ）.
After receiving clearance to takeoff from runway 23L, the captain ordered F/O to perform Before Takeoff Checklist and confirm runway 23L Final Clear, then execute time set and make right turn to line up using tiller and then transfer control to F/O. F/O did not confirm on flap 20 Set from the checklist due to read back of the takeoff clearance to the tower as he performed the Before Takeoff Checklist.F/O pushed the TOGA switch when he saw the thrust was approaching 1.1 EPR but Auto Trust did not operate, so the captain advanced the thrust by manual. At this moment, the warning horn sounded and F/O called we’d better Reject Takeoff but the captain decided to continue takeoff based on his misjudgment of lightweight(633,280lbs) and sufficient runway. The captain pulled down the flap lever and took the control and continued to takeoff. The aircraft lifted off with flap 4.9, flap 10 when passing 35 ft, flap 20 when passing 156 ft, which led the aircraft to takeoff without the required flap setting. Warning horn sounded for 22 seconds until V1, 128 kts during takeoff and the captain realized Less Flap when rotated and increased speed quickly by maintaining less pitch(less than 10 degrees).5. What was the flap setting at the moment of lift-off?
After receiving clearance to takeoff from runway 23L, the captain ordered F/O to perform Before Takeoff Checklist and confirm runway 23L Final Clear, then execute time set and make right turn to line up using tiller and then transfer control to F/O. F/O did not confirm on flap 20 Set from the checklist due to read back of the takeoff clearance to the tower as he performed the Before Takeoff Checklist.F/O pushed the TOGA switch when he saw the thrust was approaching 1.1 EPR but Auto Trust did not operate, so the captain advanced the thrust by manual. At this moment, the warning horn sounded and F/O called we’d better Reject Takeoff but the captain decided to continue takeoff based on his misjudgment of lightweight(633,280lbs) and sufficient runway. The captain pulled down the flap lever and took the control and continued to takeoff. The aircraft lifted off with flap 4.9, flap 10 when passing 35 ft, flap 20 when passing 156 ft, which led the aircraft to takeoff without the required flap setting. Warning horn sounded for 22 seconds until V1, 128 kts during takeoff and the captain realized Less Flap when rotated and increased speed quickly by maintaining less pitch(less than 10 degrees).4. Why didn’t the captain abort the takeoff?
After receiving clearance to takeoff from runway 23L, the captain ordered F/O to perform Before Takeoff Checklist and confirm runway 23L Final Clear, then execute time set and make right turn to line up using tiller and then transfer control to F/O. F/O did not confirm on flap 20 Set from the checklist due to read back of the takeoff clearance to the tower as he performed the Before Takeoff Checklist.F/O pushed the TOGA switch when he saw the thrust was approaching 1.1 EPR but Auto Trust did not operate, so the captain advanced the thrust by manual. At this moment, the warning horn sounded and F/O called we’d better Reject Takeoff but the captain decided to continue takeoff based on his misjudgment of lightweight(633,280lbs) and sufficient runway. The captain pulled down the flap lever and took the control and continued to takeoff. The aircraft lifted off with flap 4.9, flap 10 when passing 35 ft, flap 20 when passing 156 ft, which led the aircraft to takeoff without the required flap setting. Warning horn sounded for 22 seconds until V1, 128 kts during takeoff and the captain realized Less Flap when rotated and increased speed quickly by maintaining less pitch(less than 10 degrees). 3.Why did the F/O call we’d better Reject Takeoff?
After receiving clearance to takeoff from runway 23L, the captain ordered F/O to perform Before Takeoff Checklist and confirm runway 23L Final Clear, then execute time set and make right turn to line up using tiller and then transfer control to F/O. F/O did not confirm on flap 20 Set from the checklist due to read back of the takeoff clearance to the tower as he performed the Before Takeoff Checklist.F/O pushed the TOGA switch when he saw the thrust was approaching 1.1 EPR but Auto Trust did not operate, so the captain advanced the thrust by manual. At this moment, the warning horn sounded and F/O called we’d better Reject Takeoff but the captain decided to continue takeoff based on his misjudgment of lightweight(633,280lbs) and sufficient runway. The captain pulled down the flap lever and took the control and continued to takeoff. The aircraft lifted off with flap 4.9, flap 10 when passing 35 ft, flap 20 when passing 156 ft, which led the aircraft to takeoff without the required flap setting. Warning horn sounded for 22 seconds until V1, 128 kts during takeoff and the captain realized Less Flap when rotated and increased speed quickly by maintaining less pitch(less than 10 degrees). 2.Why didn’t the F/O confirm on Flaps 20 Set from the checklist according to the passage?
After receiving clearance to takeoff from runway 23L, the captain ordered F/O to perform Before Takeoff Checklist and confirm runway 23L Final Clear, then execute time set and make right turn to line up using tiller and then transfer control to F/O. F/O did not confirm on flap 20 Set from the checklist due to read back of the takeoff clearance to the tower as he performed the Before Takeoff Checklist.F/O pushed the TOGA switch when he saw the thrust was approaching 1.1 EPR but Auto Trust did not operate, so the captain advanced the thrust by manual. At this moment, the warning horn sounded and F/O called we’d better Reject Takeoff but the captain decided to continue takeoff based on his misjudgment of lightweight(633,280lbs) and sufficient runway. The captain pulled down the flap lever and took the control and continued to takeoff. The aircraft lifted off with flap 4.9, flap 10 when passing 35 ft, flap 20 when passing 156 ft, which led the aircraft to takeoff without the required flap setting. Warning horn sounded for 22 seconds until V1, 128 kts during takeoff and the captain realized Less Flap when rotated and increased speed quickly by maintaining less pitch(less than 10 degrees).1.What were the flight doing while they were lining up?
Wind shear is a sudden, drastic shift in wind speed and/or direction that may occur at any altitude in a vertical or horizontal plane. It can subject your aircraft to sudden updrafts, downdrafts, or extreme horizontal wind components, causing loss of lift or violent changes in vertical speeds or altitude. In fact, when landing during gusty conditions, you should use a power-on approach and landing to minimize the effect of the wind and to retain positive control of the aircraft. Wind shear is associated with temperature inversions, the jet stream, thunderstorms, and frontal inversions. With a temperature inversion, it occurs when cold, calm air is near the surface and warmer air aloft is in motion. This can be a hazard during climbouts or approaches when your airspeed is relatively slow. Be alert for a sudden change in airspeed and carry an extra margin of speed if you suspect an inversion.With fronts, the most critical period is either just before or just after frontal passage. With a cold front, wind shear occurs just after the front passes and for a short time after ward. Studies indicate the amount of wind shear in a warm front is generally much greater than in a cold front. The wind shear below 5,000 ft AGL in a warm front may last for ap proximately six hours. The most critical period is before the front passes; the problem ceases to exist after it passes.A microburst is an intense, localized downdraft of brief duration which spreads out in all directions when it reaches the surface. This creates severe horizontal and vertical wind shears which pose serious hazards to aircraft, particularly those near the surface. An individual mi croburst typically covers an area of less than two and a half miles in diameter at the surface and usually lasts no longer than 15 minutes. Peak winds last two to four minutes and atten dant downdrafts can be as strong as 6,000 ft per minute.Any convective cloud can produce this phenomenon. Although microbursts are commonly associated with heavy precipitation in thunderstorms, they often occur in virga. If there is no precipitation, your only cue may be a ring of dust at the surface. If you suspect the pres ence of microbursts in your local area, delay your takeoff or landing. 5.Which of the following statements is true?
Wind shear is a sudden, drastic shift in wind speed and/or direction that may occur at any altitude in a vertical or horizontal plane. It can subject your aircraft to sudden updrafts, downdrafts, or extreme horizontal wind components, causing loss of lift or violent changes in vertical speeds or altitude. In fact, when landing during gusty conditions, you should use a power-on approach and landing to minimize the effect of the wind and to retain positive control of the aircraft. Wind shear is associated with temperature inversions, the jet stream, thunderstorms, and frontal inversions. With a temperature inversion, it occurs when cold, calm air is near the surface and warmer air aloft is in motion. This can be a hazard during climbouts or approaches when your airspeed is relatively slow. Be alert for a sudden change in airspeed and carry an extra margin of speed if you suspect an inversion.With fronts, the most critical period is either just before or just after frontal passage. With a cold front, wind shear occurs just after the front passes and for a short time after ward. Studies indicate the amount of wind shear in a warm front is generally much greater than in a cold front. The wind shear below 5,000 ft AGL in a warm front may last for ap proximately six hours. The most critical period is before the front passes; the problem ceases to exist after it passes.A microburst is an intense, localized downdraft of brief duration which spreads out in all directions when it reaches the surface. This creates severe horizontal and vertical wind shears which pose serious hazards to aircraft, particularly those near the surface. An individual mi croburst typically covers an area of less than two and a half miles in diameter at the surface and usually lasts no longer than 15 minutes. Peak winds last two to four minutes and atten dant downdrafts can be as strong as 6,000 ft per minute.Any convective cloud can produce this phenomenon. Although microbursts are commonly associated with heavy precipitation in thunderstorms, they often occur in virga. If there is no precipitation, your only cue may be a ring of dust at the surface. If you suspect the pres ence of microbursts in your local area, delay your takeoff or landing.4.An individual microburst （ ） ．
Wind shear is a sudden, drastic shift in wind speed and/or direction that may occur at any altitude in a vertical or horizontal plane. It can subject your aircraft to sudden updrafts, downdrafts, or extreme horizontal wind components, causing loss of lift or violent changes in vertical speeds or altitude. In fact, when landing during gusty conditions, you should use a power-on approach and landing to minimize the effect of the wind and to retain positive control of the aircraft. Wind shear is associated with temperature inversions, the jet stream, thunderstorms, and frontal inversions. With a temperature inversion, it occurs when cold, calm air is near the surface and warmer air aloft is in motion. This can be a hazard during climbouts or approaches when your airspeed is relatively slow. Be alert for a sudden change in airspeed and carry an extra margin of speed if you suspect an inversion.With fronts, the most critical period is either just before or just after frontal passage. With a cold front, wind shear occurs just after the front passes and for a short time after ward. Studies indicate the amount of wind shear in a warm front is generally much greater than in a cold front. The wind shear below 5,000 ft AGL in a warm front may last for ap proximately six hours. The most critical period is before the front passes; the problem ceases to exist after it passes.A microburst is an intense, localized downdraft of brief duration which spreads out in all directions when it reaches the surface. This creates severe horizontal and vertical wind shears which pose serious hazards to aircraft, particularly those near the surface. An individual mi croburst typically covers an area of less than two and a half miles in diameter at the surface and usually lasts no longer than 15 minutes. Peak winds last two to four minutes and atten dant downdrafts can be as strong as 6,000 ft per minute.Any convective cloud can produce this phenomenon. Although microbursts are commonly associated with heavy precipitation in thunderstorms, they often occur in virga. If there is no precipitation, your only cue may be a ring of dust at the surface. If you suspect the pres ence of microbursts in your local area, delay your takeoff or landing.3.With a warm front, the most critical period is （ ） ．
