TCAS safety deficiency and the AIPA, AFAP and GAPAN
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TCAS safety deficiency and the AIPA, AFAP and GAPAN
It is now over 22 weeks since the Australian Financial Review newspaper published my article in relation to safety deficiencies (see here). In the intervening period I find it almost unbelievable that the Australian Federation of Air Pilots (AFAP), the Australian & International Pilots Association (AIPA) and the Guild of Air Pilots and Air Navigators (GAPAN) have not come out with a public statement asking CASA to legislate for TCAS requirements for airline aircraft of 10 to 30 passengers.
What have we seen? Almost complete silence. Some people claim it is because the Chief Pilots of the airlines concerned (covering over 150 safety deficient aircraft) are scared of losing their bonus if more money is spent on safety.
This is obviously ridiculous, as companies such as Regional Express are making really good profits at the moment and could easily afford TCAS.
When you consider that countries such as India have a mandatory requirement, and all other modern aviation countries, it is extraordinary that Australia is deficient.
Could I suggest that the unions and the guild put out a public statement supporting the move to this internationally recognised safety improvement? Why should Australian passengers have a lower prescribed level of safety when flying in airline aircraft of 10 to 30 passengers?
Remember, Australia has a mandatory requirement for VFR aircraft to have Mode C transponders in all Class E – a world first. If VFR aircraft can afford transponders surely airline aircraft can afford TCAS.
What have we seen? Almost complete silence. Some people claim it is because the Chief Pilots of the airlines concerned (covering over 150 safety deficient aircraft) are scared of losing their bonus if more money is spent on safety.
This is obviously ridiculous, as companies such as Regional Express are making really good profits at the moment and could easily afford TCAS.
When you consider that countries such as India have a mandatory requirement, and all other modern aviation countries, it is extraordinary that Australia is deficient.
Could I suggest that the unions and the guild put out a public statement supporting the move to this internationally recognised safety improvement? Why should Australian passengers have a lower prescribed level of safety when flying in airline aircraft of 10 to 30 passengers?
Remember, Australia has a mandatory requirement for VFR aircraft to have Mode C transponders in all Class E – a world first. If VFR aircraft can afford transponders surely airline aircraft can afford TCAS.
Grandpa Aerotart
Mate you didn't want transponders in E and there is no requirement for transponders in G...so what use would a TCAS be if the other aircraft is not squawking mode C?
Lost your faith in see and avoid?
Lost your faith in see and avoid?
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Hmmmm this seem to have dropped out of sight but here goes again;
Been waiting for this to appear on the website to save me typing it out the hard way.
It is IMHO the final word on the fallacy of "see and be seen" in the modern environment at least the one that I work in.
See-And-Avoid A Dangerous Way To Separate High- and Low-Performance Aircraft
Jan 17, 2007
By Patrick Veillette, Ph.D./Business & Commercial Aviation
The smoke plume on the east side of Los Angeles on the afternoon of Aug. 31, 1986, was clearly visible from the balcony of our apartment adjacent to LAX. The local news was reporting that an airliner had crashed into the suburb of Cerritos. My roommates, all Los Angeles-based pilots from a half dozen airlines, stood on the balcony watching that sick black plume rise. No one said the obvious, that the dark column marked the place of death for many.
We subsequently learned that a pilot of a Piper PA-28 had errantly wandered into what is now Class B airspace without a clearance and without an operative altitude encoding transponder. The flight crew of the Aeromexico DC-9 had only the slimmest of chances to spot and avoid the Cherokee, and unfortunately luck wasn't with them on that day. When the NTSB finalized its report, it found limitations with the "see-and-avoid concept to ensure traffic separation" as a contributing factor to the disaster that took 82 lives.
That inflight collision was eerily reminiscent of another eight years earlier when a Pacific Southwest Airlines Boeing 727 lost sight of a Cessna 172 while on approach to San Diego's Lindbergh Field. The flight crew of the fast moving 727 lost sight of the Cessna and thought they had actually passed the slower aircraft. Unfortunately they had not and 138 people died in the collision that followed. A photograph of the last moments of the 727's dive serve as a gut-wrenching reminder of the inadequacy of eyeballs as a primary collision avoidance tool.
On Jan. 15, 1987, a Mooney M20 pilot was practicing holding patterns near the extended approach path into Salt Lake International Airport and inadvertently entered SLC's airport radar service area. Approach Control wasn't receiving an altitude read-out from the Mooney's transponder and unfortunately the practice holding pattern roughly coincided with the traffic pattern for Salt Lake City Municipal No. 2 Airport, a general aviation facility located roughly six miles to the south of SLC, thus adding further confusion as to the exact location of the Mooney. At the same time a SkyWest SA-227 Metroliner was being vectored to the final approach course for SLC, its pilots attempting to locate traffic pointed out by ATC. Despite the good weather, the Metro pilots never spotted the Mooney because the two aircraft collided over Kearns, Utah, raining aircraft parts on the residential neighborhood and killing the 10 people aboard the two aircraft but somehow avoiding any loss of life or injury to people on the ground.
Just five days later, a U.S. Army U-21 King Air collided with a Piper Chieftain near Independence, Mo. Six people died in that crash. The NTSB determined that the probable cause of the accident was the failure of radar controllers to detect the conflict and to issue traffic advisories or a safety alert to the flight crew of the U-21, and the inadequate vigilance of the pilots. However, the Safety Board also cited deficiencies of the see-and-avoid concept as a primary means of collision avoidance, and the lack of automated redundancy in the air traffic control system to provide conflict detection between participating and nonparticipating traffic.
Shortly thereafter, the NTSB recommended the FAA "expedite development, certification and production of various low-cost proximity warning and conflict detection systems for use aboard general aviation aircraft."
Unfortunately, that recommendation was still unrealized when five years later, on Sept. 11, 1992, an MU-2 pilot attempting to pick up an IFR clearance while departing VFR from Greenwood (Ind.) Municipal Airport, collided with a Piper Saratoga inbound for the same airport. The controller pointed out the Greenwood airport to the PA-32's pilot when the aircraft was approximately three miles out, at which time VFR radar service was terminated. The MU-2 had just departed the airport and asked ATC for his IFR clearance to CMH. The controller looked away from the radar screen to locate the proper flight progress strip and did not see the fast-moving turboprop depart from Greenwood. The controller then issued a squawk code and altitude to establish radar identification. It was during those seconds that the incoming PA-32 and outbound MU-2 collided. The Mitsubishi pilot and four passengers and the Saratoga pilot were killed. Two people on board the Piper were seriously injured.
The NTSB determined that the probable cause of the accident was "the inherent limitations of the see-and-avoid concept of the separation of aircraft operating under VFR that precluded the pilots from recognizing a collision hazard and taking actions to avoid the collision." The report concluded that the accident "again underscores the need for low-cost proximity warning and conflict detection systems for use aboard general aviation aircraft."
Now, 20 years have passed since the NTSB issued its original recommendation to expedite development, certification and production of low-cost proximity warning and conflict detection systems for general aviation. And while some systems are in place, "see-and-avoid" remains the primary means of separation between high-performance turbine and low-performance general aviation aircraft sharing the same airspace.
While a "Mode C veil" has been erected 30 nm around Class B airports that seems effective at preventing inflight collisions there, a system-wide solution for preventing collisions in other airspace, especially where high-performance turbine aircraft mix with lower performance general aviation aircraft, has yet to be implemented.
In the meantime, the wreckage continues to pile up. On April 4, 1998, a Cessna CE525 collided with a Cessna 172 over Marietta, Ga., killing five. On June 23, 2000, a Learjet 55 collided with an Extra 300S over the busy skies of Boca Raton, Fla.; four people died as a result. On Oct. 17 of that same year, a Gulfstream GIII collided with a King Air C90 while both aircraft were on approach to Van Nuys (Calif.) Airport; the pilots managed to land their aircraft without injury to anyone aboard. Most recently, a Hawker 800XP descending into Reno collided with a Schleicher ASW-27 sailplane near Minden, Nev., a popular soaring location. Somewhat miraculously the glider pilot managed to parachute to safety and the crew of the damaged Hawker was able to execute a single-engine, gear-up emergency landing at the nearby Carson City Airport. Everybody walked away.
FAR Part 91.113 places the responsibility to see and avoid other aircraft squarely on the pilot, stating, "When weather conditions permit, regardless of whether an operation is conducted under IFR or VFR, vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft."
Using this regulatory precedent, the NTSB has found "failure to see and avoid, inadequate visual lookout, or failure to maintain visual and physical clearance" as the probable cause in 94 percent of the inflight collisions. The Safety Board can keep issuing such causal statements, but that won't change the underlying problem that the see-and-avoid concept isn't reliable as a primary or even secondary means of separating traffic.
Harold Marthinsen, former director of the Air Line Pilots Association (ALPA) safety engineering department, asks, "Do pilots really need a regulation telling them to avoid midair collisions? Pilots have a self-vested interest in preventing that from occurring. It is publications like the FAA's Advisory Circular on collision avoidance that help perpetuate the idea that all you have to do is pay attention, look out the windshield, and you won't have a midair collision. Rather, the FAA should be telling pilots how dangerous the see-and-avoid concept really is as a means of separating aircraft."
See-and-avoid involves a number of steps, all of which are inherently prone to error. First, the pilot must be looking outside the aircraft. Second, pilots must search the visual field and detect objects of interest, most likely with their peripheral vision. Next, the object must be looked at directly so it can be identified as an aircraft. If the aircraft is identified as a collision threat, the pilot must decide what evasive action to take and then follow through correctly and in a timely fashion.
So how well does the concept work? According to Craig Morris of the DOT's Bureau of Transportation Statistics, each year there are an average of 15.6 midair collisions in U.S. civil aviation, and that number may only hint at the scope of the problem. In an average year, NASA's Aviation Safety Reporting System (ASRS) receives approximately 577 pilot reports of near in-flight collisions between various types of aircraft. Specifically with regard to business jets, the FAA's near midair collision (NMAC) database included 226 NMAC reports filed by pilots of business jets for a recent 10-year period. In addition, the ASRS database for the same 10-year period had 806 reports of near midair collisions involving business jets. Just how close did some of the aircraft approach each other in these reports? Half of the reported incidents had a separation of less than 500 feet; some were even closer than that. And those are just the reported events. We really don't know how many close calls went unreported or how many pilots were simply unaware of a near disaster.
Those of us who fly the line don't need a bunch of statistics to tell us that flying into Martha's Vineyard or Nantucket (or Santa Monica, Van Nuys, etc.) on a VFR summer weekend is akin to running a gauntlet.
Writing in Aviation, Space and Environmental Medicine, a peer-reviewed journal of the Aerospace Medical Association, Morris held that "The 'see-and-avoid' concept has considerable physical and behavioral limitations such that pilots cannot reliably see and avoid conflicting traffic." A panel of reviewers would not permit an author to make such a statement unless it was backed by a preponderance of respected scientific research. Morris is among many respected aviation authorities who have expressed concerns regarding the limitations of the see-and-avoid concept.
The Australian Transport Safety Bureau issued a lengthy research report entitled "Limitations of the See-and-Avoid Principle" that stated, "Numerous limitations, including those of the human visual system, the demands of cockpit tasks, and various physical and environmental conditions, combine to make see-and-avoid an uncertain method of traffic separation." In addition, the Australian Bureau of Air Safety Investigation stated that "see-and-avoid is completely unsuitable as a primary traffic separation method for scheduled services."
Marthinsen stated in the International Society of Air Safety Investigators (ISASI) Forum (December 1989) that "See-and-avoid was originally a maritime concept developed for slow moving ships that is now out of place in an era of high-speed aviation." He went on to say that "No one is suggesting that see-and-avoid is not a useful tool for general aviation airplanes operating at uncontrolled airports -- it's the only thing available, and it works most of the time in this environment for which it was adapted. But it should not be relied upon to separate high-performance aircraft from lower performance general aviation aircraft -- a situation for which it was not designed."
There is a big difference between seeing an object under laboratory conditions vs. detecting another aircraft on a possible collision course out in "the real world." The NTSB considers 0.2 degrees as the threshold angle for detection (that is, the viewer could detect an object 20 feet wide at a distance of one mile -- Ed.), although Marthinsen says that figure should be increased by a factor of two or three for targets with low contrast or difficult patterns. The former ALPA director believes no one minimum visual angle can be specified because none can accommodate all variety of conditions such as haze, visible moisture or smoke. He noted that many visual acuity studies were done under favorable light conditions and with the subject staring directly at the object, in which case the image is focused directly on the fovea of the eye. The fovea contains the majority of the eye's cones and is responsible for the sharp vision we use in daylight conditions. If an object is six degrees from the fovea, that is, six degrees off a direct line by the viewer, it would have to be twice the size of an object directly in line in order to be detected. The threshold acuity drops off very rapidly for objects placed at angles away from the fovea. Further, all of these theoretical studies were conducted with fixed targets and viewers, never in motion.
FAA Advisory Circular 90-48C provides military-derived data on the time required for a pilot to recognize an approaching aircraft and then execute an evasive maneuver. The calculations do not include search times but assume that the target has been detected. The total time to recognize an approaching aircraft, recognize a collision course, decide on action, execute the control movement and allow the aircraft to respond is estimated to be around 12.5 seconds. Therefore, to have a good chance of avoiding a collision, a conflicting aircraft must be detected at least 12.5 seconds prior to the time of impact. It should also be noted that this study is over-optimistic for aircraft reaction time because the military study was in reference to agile fighter aircraft. The higher inertia and lesser maneuverability of civilian transports would add considerably to aircraft reaction time. The NTSB has used 15 seconds as the absolute minimum time for detection, evaluation and evasive action if the collision is to be avoided. Other studies suggest somewhat higher values.
Target detection is primarily a function of target size and target contrast, with size being, by far, the more important parameter in the ability to detect other aircraft. Unfortunately business jets and general aviation aircraft are on the "small" side of this spectrum and thus would be very difficult to see at sufficient distances to avoid a collision.
Detecting a target at jet speeds leaves very little time to see and avoid. For example, a jet descending at roughly 400 knots groundspeed covers 1.39 nm in 12.5 seconds. Let's say that the intersecting general aviation aircraft is on a roughly perpendicular flight path, thereby presenting more surface area to be detected and making it easier to see. Both the visual angle and its rate of change remain very small until imminent impact. At seven seconds to impact, a 40-foot-long aircraft would subtend only a 0.5-degree angle, which is still very small.
Walton Graham and Robert H. Orr, in a research paper entitled "Separation of Air Traffic by Visual Means: An Estimate of the Effectiveness of the See-and-Avoid Doctrine" and published in Proceedings of the IEEE (Volume 58, 1970) stated, "As speed increases, the effectiveness of 'see-and-avoid' greatly decreases. It is estimated that see-and-avoid prevents 97 percent of possible collisions at closing speeds of between 101 and 199 knots but only 47 percent when the closing speed is greater than 400 knots."
Morris continues, "Pilots can find it physically impossible to see converging traffic, especially when climbing or descending. Also, because human information processing is biased toward detection of contrast and sudden change, the small, motionless, camouflaged target projected by a rapidly converging aircraft is difficult to detect within the random and narrow window of opportunity to see it."
The human visual system is particularly attuned to detecting movement but is less effective at detecting stationary objects. Unfortunately, an aircraft on a collision course will usually appear to be a stationary object in the pilot's visual field. From each pilot's point of view, the converging aircraft will grow in size while remaining fixed at a particular point in the windscreen.
FAA Advisory Circular 90-48C recommends scanning the entire visual field outside the cockpit with eye movements of 10 degrees or less to ensure detection of conflicting traffic. The FAA estimates that approximately one second is required at each fixation. Thus, to scan an area 180 degrees horizontal and 30 degrees vertical could take 54 such fixations at one second each. A jet descending at an approximate groundspeed of 360 knots would cover roughly six miles per minute, so a pilot who faithfully follows the procedure exactly as spelled out in the Advisory Circular would see an entirely different kind of scene before completing the scan. Marthinsen has a rather negative opinion of the FAA scanning technique, stating, "It is incompatible with the physiological capability of the human eye. The time it would take to scan is substantially longer than the time available to see-and-avoid in many of the midair collision accidents."
Do pilots practice the recommended scanning pattern? According to research cited in the Australian Transport Safety Bureau's report, "Visual scans tend to be unsystematic, with some areas of the visual field receiving close attention while other areas are neglected. Areas of the sky around edges of the windscreens are generally scanned less than the sky in the center, and saccades [motion of eye between fixations -- Ed.] may be too large, leaving large areas of unsearched space between fixation points."
Furthermore, researchers have known for many years that in the absence of visual cues, the eye will focus at a relatively short distance. In an empty field such as a limitless blue sky, the eye will focus at around 56 centimeters (1.8 feet). This effect is known as "empty field myopia" and can reduce the chance of identifying a distant object. Because the natural focus point is around a half meter (1.6 feet) away, it requires an effort to focus at greater distances, particularly in the absence of visual cues.
A U.S. study in 1976 found that private pilots on VFR flights spend about 50 percent of their time in outside traffic scan during cruise flight, although this drops off to 40 percent during departure and approach. Even motivated pilots under ideal conditions frequently fail to sight conflicting traffic. A research project conducted by John W. Andrews of the Massachusetts Institute of Technology's Lincoln Laboratory involved 24 general aviation pilots flying a Beech Bonanza on a VFR cross country. The pilots were not aware that their aircraft would be intercepted several times by a Cessna 421 flying a near-collision course. The pilots spotted 36 out of 64 encounters, a 56-percent detection rate. Keep in mind that this study involved comparatively low-speed traffic operating under ideal detection conditions. The MIT study concluded that the ability of pilots to detect aircraft on near-collision courses is not great.Capt. Harry Orlady, a well-respected human factors researcher and former United Air Lines pilot, published a paper with the National Research Council estimating that airline pilots spend about 20 percent of their time in outside scan. A United-ALPA study of airline crews determined that "no one is looking during climb at least 62 percent of the time and 52 percent of the time during descent."
cont'd
Been waiting for this to appear on the website to save me typing it out the hard way.
It is IMHO the final word on the fallacy of "see and be seen" in the modern environment at least the one that I work in.
See-And-Avoid A Dangerous Way To Separate High- and Low-Performance Aircraft
Jan 17, 2007
By Patrick Veillette, Ph.D./Business & Commercial Aviation
The smoke plume on the east side of Los Angeles on the afternoon of Aug. 31, 1986, was clearly visible from the balcony of our apartment adjacent to LAX. The local news was reporting that an airliner had crashed into the suburb of Cerritos. My roommates, all Los Angeles-based pilots from a half dozen airlines, stood on the balcony watching that sick black plume rise. No one said the obvious, that the dark column marked the place of death for many.
We subsequently learned that a pilot of a Piper PA-28 had errantly wandered into what is now Class B airspace without a clearance and without an operative altitude encoding transponder. The flight crew of the Aeromexico DC-9 had only the slimmest of chances to spot and avoid the Cherokee, and unfortunately luck wasn't with them on that day. When the NTSB finalized its report, it found limitations with the "see-and-avoid concept to ensure traffic separation" as a contributing factor to the disaster that took 82 lives.
That inflight collision was eerily reminiscent of another eight years earlier when a Pacific Southwest Airlines Boeing 727 lost sight of a Cessna 172 while on approach to San Diego's Lindbergh Field. The flight crew of the fast moving 727 lost sight of the Cessna and thought they had actually passed the slower aircraft. Unfortunately they had not and 138 people died in the collision that followed. A photograph of the last moments of the 727's dive serve as a gut-wrenching reminder of the inadequacy of eyeballs as a primary collision avoidance tool.
On Jan. 15, 1987, a Mooney M20 pilot was practicing holding patterns near the extended approach path into Salt Lake International Airport and inadvertently entered SLC's airport radar service area. Approach Control wasn't receiving an altitude read-out from the Mooney's transponder and unfortunately the practice holding pattern roughly coincided with the traffic pattern for Salt Lake City Municipal No. 2 Airport, a general aviation facility located roughly six miles to the south of SLC, thus adding further confusion as to the exact location of the Mooney. At the same time a SkyWest SA-227 Metroliner was being vectored to the final approach course for SLC, its pilots attempting to locate traffic pointed out by ATC. Despite the good weather, the Metro pilots never spotted the Mooney because the two aircraft collided over Kearns, Utah, raining aircraft parts on the residential neighborhood and killing the 10 people aboard the two aircraft but somehow avoiding any loss of life or injury to people on the ground.
Just five days later, a U.S. Army U-21 King Air collided with a Piper Chieftain near Independence, Mo. Six people died in that crash. The NTSB determined that the probable cause of the accident was the failure of radar controllers to detect the conflict and to issue traffic advisories or a safety alert to the flight crew of the U-21, and the inadequate vigilance of the pilots. However, the Safety Board also cited deficiencies of the see-and-avoid concept as a primary means of collision avoidance, and the lack of automated redundancy in the air traffic control system to provide conflict detection between participating and nonparticipating traffic.
Shortly thereafter, the NTSB recommended the FAA "expedite development, certification and production of various low-cost proximity warning and conflict detection systems for use aboard general aviation aircraft."
Unfortunately, that recommendation was still unrealized when five years later, on Sept. 11, 1992, an MU-2 pilot attempting to pick up an IFR clearance while departing VFR from Greenwood (Ind.) Municipal Airport, collided with a Piper Saratoga inbound for the same airport. The controller pointed out the Greenwood airport to the PA-32's pilot when the aircraft was approximately three miles out, at which time VFR radar service was terminated. The MU-2 had just departed the airport and asked ATC for his IFR clearance to CMH. The controller looked away from the radar screen to locate the proper flight progress strip and did not see the fast-moving turboprop depart from Greenwood. The controller then issued a squawk code and altitude to establish radar identification. It was during those seconds that the incoming PA-32 and outbound MU-2 collided. The Mitsubishi pilot and four passengers and the Saratoga pilot were killed. Two people on board the Piper were seriously injured.
The NTSB determined that the probable cause of the accident was "the inherent limitations of the see-and-avoid concept of the separation of aircraft operating under VFR that precluded the pilots from recognizing a collision hazard and taking actions to avoid the collision." The report concluded that the accident "again underscores the need for low-cost proximity warning and conflict detection systems for use aboard general aviation aircraft."
Now, 20 years have passed since the NTSB issued its original recommendation to expedite development, certification and production of low-cost proximity warning and conflict detection systems for general aviation. And while some systems are in place, "see-and-avoid" remains the primary means of separation between high-performance turbine and low-performance general aviation aircraft sharing the same airspace.
While a "Mode C veil" has been erected 30 nm around Class B airports that seems effective at preventing inflight collisions there, a system-wide solution for preventing collisions in other airspace, especially where high-performance turbine aircraft mix with lower performance general aviation aircraft, has yet to be implemented.
In the meantime, the wreckage continues to pile up. On April 4, 1998, a Cessna CE525 collided with a Cessna 172 over Marietta, Ga., killing five. On June 23, 2000, a Learjet 55 collided with an Extra 300S over the busy skies of Boca Raton, Fla.; four people died as a result. On Oct. 17 of that same year, a Gulfstream GIII collided with a King Air C90 while both aircraft were on approach to Van Nuys (Calif.) Airport; the pilots managed to land their aircraft without injury to anyone aboard. Most recently, a Hawker 800XP descending into Reno collided with a Schleicher ASW-27 sailplane near Minden, Nev., a popular soaring location. Somewhat miraculously the glider pilot managed to parachute to safety and the crew of the damaged Hawker was able to execute a single-engine, gear-up emergency landing at the nearby Carson City Airport. Everybody walked away.
FAR Part 91.113 places the responsibility to see and avoid other aircraft squarely on the pilot, stating, "When weather conditions permit, regardless of whether an operation is conducted under IFR or VFR, vigilance shall be maintained by each person operating an aircraft so as to see and avoid other aircraft."
Using this regulatory precedent, the NTSB has found "failure to see and avoid, inadequate visual lookout, or failure to maintain visual and physical clearance" as the probable cause in 94 percent of the inflight collisions. The Safety Board can keep issuing such causal statements, but that won't change the underlying problem that the see-and-avoid concept isn't reliable as a primary or even secondary means of separating traffic.
Harold Marthinsen, former director of the Air Line Pilots Association (ALPA) safety engineering department, asks, "Do pilots really need a regulation telling them to avoid midair collisions? Pilots have a self-vested interest in preventing that from occurring. It is publications like the FAA's Advisory Circular on collision avoidance that help perpetuate the idea that all you have to do is pay attention, look out the windshield, and you won't have a midair collision. Rather, the FAA should be telling pilots how dangerous the see-and-avoid concept really is as a means of separating aircraft."
See-and-avoid involves a number of steps, all of which are inherently prone to error. First, the pilot must be looking outside the aircraft. Second, pilots must search the visual field and detect objects of interest, most likely with their peripheral vision. Next, the object must be looked at directly so it can be identified as an aircraft. If the aircraft is identified as a collision threat, the pilot must decide what evasive action to take and then follow through correctly and in a timely fashion.
So how well does the concept work? According to Craig Morris of the DOT's Bureau of Transportation Statistics, each year there are an average of 15.6 midair collisions in U.S. civil aviation, and that number may only hint at the scope of the problem. In an average year, NASA's Aviation Safety Reporting System (ASRS) receives approximately 577 pilot reports of near in-flight collisions between various types of aircraft. Specifically with regard to business jets, the FAA's near midair collision (NMAC) database included 226 NMAC reports filed by pilots of business jets for a recent 10-year period. In addition, the ASRS database for the same 10-year period had 806 reports of near midair collisions involving business jets. Just how close did some of the aircraft approach each other in these reports? Half of the reported incidents had a separation of less than 500 feet; some were even closer than that. And those are just the reported events. We really don't know how many close calls went unreported or how many pilots were simply unaware of a near disaster.
Those of us who fly the line don't need a bunch of statistics to tell us that flying into Martha's Vineyard or Nantucket (or Santa Monica, Van Nuys, etc.) on a VFR summer weekend is akin to running a gauntlet.
Writing in Aviation, Space and Environmental Medicine, a peer-reviewed journal of the Aerospace Medical Association, Morris held that "The 'see-and-avoid' concept has considerable physical and behavioral limitations such that pilots cannot reliably see and avoid conflicting traffic." A panel of reviewers would not permit an author to make such a statement unless it was backed by a preponderance of respected scientific research. Morris is among many respected aviation authorities who have expressed concerns regarding the limitations of the see-and-avoid concept.
The Australian Transport Safety Bureau issued a lengthy research report entitled "Limitations of the See-and-Avoid Principle" that stated, "Numerous limitations, including those of the human visual system, the demands of cockpit tasks, and various physical and environmental conditions, combine to make see-and-avoid an uncertain method of traffic separation." In addition, the Australian Bureau of Air Safety Investigation stated that "see-and-avoid is completely unsuitable as a primary traffic separation method for scheduled services."
Marthinsen stated in the International Society of Air Safety Investigators (ISASI) Forum (December 1989) that "See-and-avoid was originally a maritime concept developed for slow moving ships that is now out of place in an era of high-speed aviation." He went on to say that "No one is suggesting that see-and-avoid is not a useful tool for general aviation airplanes operating at uncontrolled airports -- it's the only thing available, and it works most of the time in this environment for which it was adapted. But it should not be relied upon to separate high-performance aircraft from lower performance general aviation aircraft -- a situation for which it was not designed."
There is a big difference between seeing an object under laboratory conditions vs. detecting another aircraft on a possible collision course out in "the real world." The NTSB considers 0.2 degrees as the threshold angle for detection (that is, the viewer could detect an object 20 feet wide at a distance of one mile -- Ed.), although Marthinsen says that figure should be increased by a factor of two or three for targets with low contrast or difficult patterns. The former ALPA director believes no one minimum visual angle can be specified because none can accommodate all variety of conditions such as haze, visible moisture or smoke. He noted that many visual acuity studies were done under favorable light conditions and with the subject staring directly at the object, in which case the image is focused directly on the fovea of the eye. The fovea contains the majority of the eye's cones and is responsible for the sharp vision we use in daylight conditions. If an object is six degrees from the fovea, that is, six degrees off a direct line by the viewer, it would have to be twice the size of an object directly in line in order to be detected. The threshold acuity drops off very rapidly for objects placed at angles away from the fovea. Further, all of these theoretical studies were conducted with fixed targets and viewers, never in motion.
FAA Advisory Circular 90-48C provides military-derived data on the time required for a pilot to recognize an approaching aircraft and then execute an evasive maneuver. The calculations do not include search times but assume that the target has been detected. The total time to recognize an approaching aircraft, recognize a collision course, decide on action, execute the control movement and allow the aircraft to respond is estimated to be around 12.5 seconds. Therefore, to have a good chance of avoiding a collision, a conflicting aircraft must be detected at least 12.5 seconds prior to the time of impact. It should also be noted that this study is over-optimistic for aircraft reaction time because the military study was in reference to agile fighter aircraft. The higher inertia and lesser maneuverability of civilian transports would add considerably to aircraft reaction time. The NTSB has used 15 seconds as the absolute minimum time for detection, evaluation and evasive action if the collision is to be avoided. Other studies suggest somewhat higher values.
Target detection is primarily a function of target size and target contrast, with size being, by far, the more important parameter in the ability to detect other aircraft. Unfortunately business jets and general aviation aircraft are on the "small" side of this spectrum and thus would be very difficult to see at sufficient distances to avoid a collision.
Detecting a target at jet speeds leaves very little time to see and avoid. For example, a jet descending at roughly 400 knots groundspeed covers 1.39 nm in 12.5 seconds. Let's say that the intersecting general aviation aircraft is on a roughly perpendicular flight path, thereby presenting more surface area to be detected and making it easier to see. Both the visual angle and its rate of change remain very small until imminent impact. At seven seconds to impact, a 40-foot-long aircraft would subtend only a 0.5-degree angle, which is still very small.
Walton Graham and Robert H. Orr, in a research paper entitled "Separation of Air Traffic by Visual Means: An Estimate of the Effectiveness of the See-and-Avoid Doctrine" and published in Proceedings of the IEEE (Volume 58, 1970) stated, "As speed increases, the effectiveness of 'see-and-avoid' greatly decreases. It is estimated that see-and-avoid prevents 97 percent of possible collisions at closing speeds of between 101 and 199 knots but only 47 percent when the closing speed is greater than 400 knots."
Morris continues, "Pilots can find it physically impossible to see converging traffic, especially when climbing or descending. Also, because human information processing is biased toward detection of contrast and sudden change, the small, motionless, camouflaged target projected by a rapidly converging aircraft is difficult to detect within the random and narrow window of opportunity to see it."
The human visual system is particularly attuned to detecting movement but is less effective at detecting stationary objects. Unfortunately, an aircraft on a collision course will usually appear to be a stationary object in the pilot's visual field. From each pilot's point of view, the converging aircraft will grow in size while remaining fixed at a particular point in the windscreen.
FAA Advisory Circular 90-48C recommends scanning the entire visual field outside the cockpit with eye movements of 10 degrees or less to ensure detection of conflicting traffic. The FAA estimates that approximately one second is required at each fixation. Thus, to scan an area 180 degrees horizontal and 30 degrees vertical could take 54 such fixations at one second each. A jet descending at an approximate groundspeed of 360 knots would cover roughly six miles per minute, so a pilot who faithfully follows the procedure exactly as spelled out in the Advisory Circular would see an entirely different kind of scene before completing the scan. Marthinsen has a rather negative opinion of the FAA scanning technique, stating, "It is incompatible with the physiological capability of the human eye. The time it would take to scan is substantially longer than the time available to see-and-avoid in many of the midair collision accidents."
Do pilots practice the recommended scanning pattern? According to research cited in the Australian Transport Safety Bureau's report, "Visual scans tend to be unsystematic, with some areas of the visual field receiving close attention while other areas are neglected. Areas of the sky around edges of the windscreens are generally scanned less than the sky in the center, and saccades [motion of eye between fixations -- Ed.] may be too large, leaving large areas of unsearched space between fixation points."
Furthermore, researchers have known for many years that in the absence of visual cues, the eye will focus at a relatively short distance. In an empty field such as a limitless blue sky, the eye will focus at around 56 centimeters (1.8 feet). This effect is known as "empty field myopia" and can reduce the chance of identifying a distant object. Because the natural focus point is around a half meter (1.6 feet) away, it requires an effort to focus at greater distances, particularly in the absence of visual cues.
A U.S. study in 1976 found that private pilots on VFR flights spend about 50 percent of their time in outside traffic scan during cruise flight, although this drops off to 40 percent during departure and approach. Even motivated pilots under ideal conditions frequently fail to sight conflicting traffic. A research project conducted by John W. Andrews of the Massachusetts Institute of Technology's Lincoln Laboratory involved 24 general aviation pilots flying a Beech Bonanza on a VFR cross country. The pilots were not aware that their aircraft would be intercepted several times by a Cessna 421 flying a near-collision course. The pilots spotted 36 out of 64 encounters, a 56-percent detection rate. Keep in mind that this study involved comparatively low-speed traffic operating under ideal detection conditions. The MIT study concluded that the ability of pilots to detect aircraft on near-collision courses is not great.Capt. Harry Orlady, a well-respected human factors researcher and former United Air Lines pilot, published a paper with the National Research Council estimating that airline pilots spend about 20 percent of their time in outside scan. A United-ALPA study of airline crews determined that "no one is looking during climb at least 62 percent of the time and 52 percent of the time during descent."
cont'd
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Part the twoth
Earl Wiener, Ph.D., professor of management science and industrial engineering at the University of Miami, Florida, found that pilots whose aircraft are equipped with glass cockpits spend more "head down" time, particularly at low altitudes, as they interact with their flight management systems. These findings were also confirmed in a study (written by yours truly) published in the Transportation Research Record, a peer-reviewed journal of the National Research Council. That study concluded that pilots of automated cockpits, especially during high workload periods in terminal airspace, had a lower likelihood than pilots flying "steam gauges" of detecting aircraft on a collision course.
The increase of inside-the-cockpit duties (such as programming FMSes, running checklists and adjusting systems) has an additional negative effect on the see-and-avoid principle. The human eye is brought into focus by muscle movements, which change the shape of the eye lens. It takes time for the eyes to refocus from viewing objects inside the cockpit to those outside. This process is called "accommodation."
A young person will typically require about one second to accommodate to a stimulus; however, the speed and degree of accommodation decreases with age, which is a separate issue from the general degradation in visual acuity that often occurs with aging. Of further concern is the increased time required for accommodation as a pilot becomes fatigued.
The average person has a visual field of about 190 degrees, although field of vision varies from person to person and is generally greater for females than males. The field of vision begins to contract after age 35, and in males, this reduction accelerates markedly after 55 years of age.
A number of transient and psychological conditions such as vibration, fatigue, hypoxia or, more than likely, cockpit workload can cause the effective field of vision to contract even further. Experiments conducted at the NASA Ames Research Center indicated that a concurrent task could reduce pilot eye movements by up to 60 percent.
The small visual angle of an approaching aircraft may make it impossible for a pilot to detect the aircraft in time to take evasive action. Since thin wings on aircraft such as gliders are almost invisible when viewed from ahead or behind, such an aircraft must approach even closer before it presents a target of detectable size. In a special study conducted by MIT's Lincoln Lab for the NTSB's investigation of the 1986 Cerritos accident, the estimated probability of visual acquisition of a general aviation aircraft with one pilot looking out the cockpit is just under 20 percent at a range of just one mile.
Further limiting the ability of pilots to see and avoid is the design of flight deck windows. Most cockpits severely limit the pilot's field of view. Obstructions to vision can include window posts, instrument and annunciator panels, glareshields, sun visors, eyeglass rims, windscreen bug splatter, windscreen imperfections, wings and the pilot beside you. Obstructions will not only mask some of the view completely, but will result in certain areas of the outside world being visible to only one eye, making it less likely to be detected. The eye has a natural blind spot at the point where the optic nerve exits the eyeball. Under normal conditions of binocular vision, the blind spot is not a problem as the area of the visual field falling on the blind spot of one eye will still be visible to the other eye.
However, if the view from one eye is obstructed (such as by a window post), then objects in the blind spot of the remaining eye will be invisible. Bearing in mind that an aircraft on a collision course appears stationary in the visual field, the blind spot could potentially mask a conflicting aircraft. The blind spot covers a visual angle of about five degrees horizontal, which is roughly 18 meters (59 feet) at a distance of 200 meters (656 feet), or enough to obscure a Hawker. A second undesirable effect of a window post or similar obstruction is that it can draw the point of focus inward, resulting not only in blurred vision but distorted perception of size and distance.
When the size of a target becomes large enough, a pilot may see the target, if he is looking directly in that direction. Assuming a pilot has adequate visual acuity and adequate vision outside of the cockpit, there are still many reasons limiting his ability to see another aircraft on a collision course.
Detecting traffic can be difficult because aircraft usually appear against complex backgrounds of clouds or terrain. The human eye is very attuned to detecting borders between objects, but in the absence of contours, the visual system rapidly loses efficiency.
So would painting all aircraft bright orange help pilots spot traffic? Not really. The color of an aircraft is less important than the aircraft's contrast, that is its difference in brightness with its background, and it's one of the major determinants of detectability. Contrast also involves reflectivity, background complexity and atmospheric visibility. A good example of contrast is the black letters on a white eye chart. With good lighting the letters can be easily observed in a doctor's office. However, out in the real world, identifying a target is much more difficult when an aircraft is viewed against the background of a city. A dark aircraft will be seen best against a light background, such as bright sky, while a light-colored aircraft will be most conspicuous against a dull background such as a forest. Contrast is further reduced when small particles of haze scatter light. Not only does haze scatter some light away from the observer, but it also scatters some light from the aircraft so that it appears to originate from the background, while light from the background is scattered into the eye's image of the aircraft.
In addition, glare can come directly from the light source or can take the form of veiling glare, reflected from crazing or dirt on the windscreen.
Furthermore, a pilot's age will affect his tolerance for glare. In general, older pilots will be more sensitive to glare.
TCAS was obviously motivated by the tragic accidents stemming from the limitations of the see-and-avoid concept. Those who have flown with TCAS know what a tremendous tool it can be. A common anecdotal observation by many colleagues is that without TCAS, they would miss the majority of traffic that would approach their aircraft at a close range. Human factors research noted by the Australian Transport Safety Bureau found that a traffic search in the absence of traffic information (i.e., no ATC alert, no TCAS TA) is less likely to be successful than a search where traffic information has been provided because knowing where to look greatly increases the chance of sighting the traffic. In fact, traffic alerts were found to increase search effectiveness by a factor of eight.
Providing additional evidence to the efficacy of TCAS-like advisories was the MIT Lincoln Laboratory study cited earlier. The same pilots in the study were given "TCAS-type" advisories as a second part of the research project. In this trial, 57 of the 66 encounters were acquired visually (as opposed to 36 out of 64 encounters without the TCAS-like advisory), with the median range of acquisition being 1.4 nm.
Has TCAS II been a successful factor in preventing collisions? Absolutely. In fact, TCAS II was cited as a factor in detecting and avoiding further loss of separation in 78 percent of reported NMACs in a recent 10-year period. Fifty-nine percent of the reported NMACs involved a resolution advisory from a TCAS II. However, like any warning system, it could not be designed to be absolutely effective in every situation. Fifteen percent of the business jets involved in NMACs were not equipped with TCAS II. In 8 percent of the ASRS reports, the "target aircraft" was not ordinarily equipped with an altitude encoding transponder. TCAS will not provide maximum protection from inflight collisions unless and until all aircraft are equipped with Mode C transponders or its equivalent.
Given the many limitations of the see-and-avoid concept, what must be done to ensure sufficient separation between high-performance and light, general aviation aircraft sharing the same airspace? Arguably, a multilayered protective system is needed in case one or two layers fail, and by design it should offset the fallibility of the see-and-avoid concept. This conclusion isn't my opinion, but rather stems from recommendations from respected organizations and authorities. The Australian Transport Safety Bureau's report stated, "Unalerted see-and-avoid has a limited place as a last resort means of traffic separation at low closing speeds, but is not sufficiently reliable to warrant a greater role in the air traffic system. Australia's Bureau of Air Safety Investigation considers that see-and-avoid is completely unsuitable as a primary traffic separation method for high-speed jet traffic."The separation of high-performance traffic from low-performance traffic has been previously suggested in the United States. In the aftermath of the MU-2/PA-32 accident near Greenwood, Ind., the NTSB suggested that "consideration should be given to establishing entry and departure corridors for high-performance airplanes that are separate from low-performance airplanes at uncontrolled airports."
Airspace separation would be just one layer in a multilayered remedy. "While visual scanning is necessary to prevent midair collisions, it is not sufficient," said the DOT's Morris, who continued, "Potential mitigation strategies include reliable altitude encoding transponders activated at all times in all aircraft, and affordable and reliable collision avoidance technologies in all general aviation aircraft, as the NTSB recommended in 1987."
In today's era of GPS precision, digital cockpits and synthetic vision, the fact that we still depend on the old, fallible "Mark VIII eyeball" to avoid midair collisions is confounding and dangerous. The rate of inflight collisions isn't likely to improve markedly until we get serious about implementing technological and procedural remedies to address this serious, continuing hazard.
And what Chuckles said.
Earl Wiener, Ph.D., professor of management science and industrial engineering at the University of Miami, Florida, found that pilots whose aircraft are equipped with glass cockpits spend more "head down" time, particularly at low altitudes, as they interact with their flight management systems. These findings were also confirmed in a study (written by yours truly) published in the Transportation Research Record, a peer-reviewed journal of the National Research Council. That study concluded that pilots of automated cockpits, especially during high workload periods in terminal airspace, had a lower likelihood than pilots flying "steam gauges" of detecting aircraft on a collision course.
The increase of inside-the-cockpit duties (such as programming FMSes, running checklists and adjusting systems) has an additional negative effect on the see-and-avoid principle. The human eye is brought into focus by muscle movements, which change the shape of the eye lens. It takes time for the eyes to refocus from viewing objects inside the cockpit to those outside. This process is called "accommodation."
A young person will typically require about one second to accommodate to a stimulus; however, the speed and degree of accommodation decreases with age, which is a separate issue from the general degradation in visual acuity that often occurs with aging. Of further concern is the increased time required for accommodation as a pilot becomes fatigued.
The average person has a visual field of about 190 degrees, although field of vision varies from person to person and is generally greater for females than males. The field of vision begins to contract after age 35, and in males, this reduction accelerates markedly after 55 years of age.
A number of transient and psychological conditions such as vibration, fatigue, hypoxia or, more than likely, cockpit workload can cause the effective field of vision to contract even further. Experiments conducted at the NASA Ames Research Center indicated that a concurrent task could reduce pilot eye movements by up to 60 percent.
The small visual angle of an approaching aircraft may make it impossible for a pilot to detect the aircraft in time to take evasive action. Since thin wings on aircraft such as gliders are almost invisible when viewed from ahead or behind, such an aircraft must approach even closer before it presents a target of detectable size. In a special study conducted by MIT's Lincoln Lab for the NTSB's investigation of the 1986 Cerritos accident, the estimated probability of visual acquisition of a general aviation aircraft with one pilot looking out the cockpit is just under 20 percent at a range of just one mile.
Further limiting the ability of pilots to see and avoid is the design of flight deck windows. Most cockpits severely limit the pilot's field of view. Obstructions to vision can include window posts, instrument and annunciator panels, glareshields, sun visors, eyeglass rims, windscreen bug splatter, windscreen imperfections, wings and the pilot beside you. Obstructions will not only mask some of the view completely, but will result in certain areas of the outside world being visible to only one eye, making it less likely to be detected. The eye has a natural blind spot at the point where the optic nerve exits the eyeball. Under normal conditions of binocular vision, the blind spot is not a problem as the area of the visual field falling on the blind spot of one eye will still be visible to the other eye.
However, if the view from one eye is obstructed (such as by a window post), then objects in the blind spot of the remaining eye will be invisible. Bearing in mind that an aircraft on a collision course appears stationary in the visual field, the blind spot could potentially mask a conflicting aircraft. The blind spot covers a visual angle of about five degrees horizontal, which is roughly 18 meters (59 feet) at a distance of 200 meters (656 feet), or enough to obscure a Hawker. A second undesirable effect of a window post or similar obstruction is that it can draw the point of focus inward, resulting not only in blurred vision but distorted perception of size and distance.
When the size of a target becomes large enough, a pilot may see the target, if he is looking directly in that direction. Assuming a pilot has adequate visual acuity and adequate vision outside of the cockpit, there are still many reasons limiting his ability to see another aircraft on a collision course.
Detecting traffic can be difficult because aircraft usually appear against complex backgrounds of clouds or terrain. The human eye is very attuned to detecting borders between objects, but in the absence of contours, the visual system rapidly loses efficiency.
So would painting all aircraft bright orange help pilots spot traffic? Not really. The color of an aircraft is less important than the aircraft's contrast, that is its difference in brightness with its background, and it's one of the major determinants of detectability. Contrast also involves reflectivity, background complexity and atmospheric visibility. A good example of contrast is the black letters on a white eye chart. With good lighting the letters can be easily observed in a doctor's office. However, out in the real world, identifying a target is much more difficult when an aircraft is viewed against the background of a city. A dark aircraft will be seen best against a light background, such as bright sky, while a light-colored aircraft will be most conspicuous against a dull background such as a forest. Contrast is further reduced when small particles of haze scatter light. Not only does haze scatter some light away from the observer, but it also scatters some light from the aircraft so that it appears to originate from the background, while light from the background is scattered into the eye's image of the aircraft.
In addition, glare can come directly from the light source or can take the form of veiling glare, reflected from crazing or dirt on the windscreen.
Furthermore, a pilot's age will affect his tolerance for glare. In general, older pilots will be more sensitive to glare.
TCAS was obviously motivated by the tragic accidents stemming from the limitations of the see-and-avoid concept. Those who have flown with TCAS know what a tremendous tool it can be. A common anecdotal observation by many colleagues is that without TCAS, they would miss the majority of traffic that would approach their aircraft at a close range. Human factors research noted by the Australian Transport Safety Bureau found that a traffic search in the absence of traffic information (i.e., no ATC alert, no TCAS TA) is less likely to be successful than a search where traffic information has been provided because knowing where to look greatly increases the chance of sighting the traffic. In fact, traffic alerts were found to increase search effectiveness by a factor of eight.
Providing additional evidence to the efficacy of TCAS-like advisories was the MIT Lincoln Laboratory study cited earlier. The same pilots in the study were given "TCAS-type" advisories as a second part of the research project. In this trial, 57 of the 66 encounters were acquired visually (as opposed to 36 out of 64 encounters without the TCAS-like advisory), with the median range of acquisition being 1.4 nm.
Has TCAS II been a successful factor in preventing collisions? Absolutely. In fact, TCAS II was cited as a factor in detecting and avoiding further loss of separation in 78 percent of reported NMACs in a recent 10-year period. Fifty-nine percent of the reported NMACs involved a resolution advisory from a TCAS II. However, like any warning system, it could not be designed to be absolutely effective in every situation. Fifteen percent of the business jets involved in NMACs were not equipped with TCAS II. In 8 percent of the ASRS reports, the "target aircraft" was not ordinarily equipped with an altitude encoding transponder. TCAS will not provide maximum protection from inflight collisions unless and until all aircraft are equipped with Mode C transponders or its equivalent.
Given the many limitations of the see-and-avoid concept, what must be done to ensure sufficient separation between high-performance and light, general aviation aircraft sharing the same airspace? Arguably, a multilayered protective system is needed in case one or two layers fail, and by design it should offset the fallibility of the see-and-avoid concept. This conclusion isn't my opinion, but rather stems from recommendations from respected organizations and authorities. The Australian Transport Safety Bureau's report stated, "Unalerted see-and-avoid has a limited place as a last resort means of traffic separation at low closing speeds, but is not sufficiently reliable to warrant a greater role in the air traffic system. Australia's Bureau of Air Safety Investigation considers that see-and-avoid is completely unsuitable as a primary traffic separation method for high-speed jet traffic."The separation of high-performance traffic from low-performance traffic has been previously suggested in the United States. In the aftermath of the MU-2/PA-32 accident near Greenwood, Ind., the NTSB suggested that "consideration should be given to establishing entry and departure corridors for high-performance airplanes that are separate from low-performance airplanes at uncontrolled airports."
Airspace separation would be just one layer in a multilayered remedy. "While visual scanning is necessary to prevent midair collisions, it is not sufficient," said the DOT's Morris, who continued, "Potential mitigation strategies include reliable altitude encoding transponders activated at all times in all aircraft, and affordable and reliable collision avoidance technologies in all general aviation aircraft, as the NTSB recommended in 1987."
In today's era of GPS precision, digital cockpits and synthetic vision, the fact that we still depend on the old, fallible "Mark VIII eyeball" to avoid midair collisions is confounding and dangerous. The rate of inflight collisions isn't likely to improve markedly until we get serious about implementing technological and procedural remedies to address this serious, continuing hazard.
And what Chuckles said.
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Chuck,
I have had this debate with Dick privately, and I have posted on here in a similar manner, so here is my bottom of the aviation food chain opinion.
Anything that flies should have a minimum Mode C Transponder and we should all be going for 100% ADSB as was being promoted last year. And the GA fleet being equipped by the savings in Radar installation and repairs being avoided.
All things that fly......OK Pelicans, crows and sparrows are exempt!
If I can have it in my plastic bug smasher, so can everyone else. Gliders RAA GA and RPT. Its not that expensive and when GA is subsidised for ADSB its a no brainer.
OK.......hard hat on.....into my bunker!
J
I have had this debate with Dick privately, and I have posted on here in a similar manner, so here is my bottom of the aviation food chain opinion.
Anything that flies should have a minimum Mode C Transponder and we should all be going for 100% ADSB as was being promoted last year. And the GA fleet being equipped by the savings in Radar installation and repairs being avoided.
All things that fly......OK Pelicans, crows and sparrows are exempt!
If I can have it in my plastic bug smasher, so can everyone else. Gliders RAA GA and RPT. Its not that expensive and when GA is subsidised for ADSB its a no brainer.
OK.......hard hat on.....into my bunker!
J
J430, agree with u mate
However, I would believe that Dick doesn't like your view on ADS-B. If Dick would so wish, he could have his cake an eat it if he promoted ADS-B with integrated MFD in all RPT aircraft. ADS-B will work outside radar coverage or even outside ADS ground coverage for that matter. Flat earthers believe that an ADS-B unit with traffic will distract an airman from looking out the window. I disagree, the result will be opposite. Alerted to traffic, you will look in the direction indicated for visual contact.
Standby, only a minimum of 5 months until the next Federal election
Just to add, TCAS is terribly expensive, ADS-B isn't!
However, I would believe that Dick doesn't like your view on ADS-B. If Dick would so wish, he could have his cake an eat it if he promoted ADS-B with integrated MFD in all RPT aircraft. ADS-B will work outside radar coverage or even outside ADS ground coverage for that matter. Flat earthers believe that an ADS-B unit with traffic will distract an airman from looking out the window. I disagree, the result will be opposite. Alerted to traffic, you will look in the direction indicated for visual contact.Standby, only a minimum of 5 months until the next Federal election
Just to add, TCAS is terribly expensive, ADS-B isn't!
In a perfect world, yes, you would have to agree that having TCAS is better than not having it.
However, when you bring in a cost-benefit analysis ... and compare the chances of Australian ATC cocking it up as against India's record ... perhaps the figures don't add up.
However, when you bring in a cost-benefit analysis ... and compare the chances of Australian ATC cocking it up as against India's record ... perhaps the figures don't add up.
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OZBUSDRIVER
thanks for that, it just makes sense, and if the GA fleet had the gear provided I would even fit it myself, (I can) and when there is a local manufacturer who has it developed and ready to go its just crazy not to.
Whats more this locally owned and locally made product actually gives you the ADSB out and in, it means Mr Bugsmasher like me can also have the traffic display like the RPT boys for not much more $$$ if we so desired.
I really fail to see any valid excuse for not doing it. None whatsoever, in fact i am that one minded on the topic now, I could almost become adament we should do it.
For those who have not looked lately go here and have a read of what is actually ready for market, or almost ready.
http://www.microair.com.au/admin/upl..._Spec_Rev2.pdf
Cheers
J
thanks for that, it just makes sense, and if the GA fleet had the gear provided I would even fit it myself, (I can) and when there is a local manufacturer who has it developed and ready to go its just crazy not to.
Whats more this locally owned and locally made product actually gives you the ADSB out and in, it means Mr Bugsmasher like me can also have the traffic display like the RPT boys for not much more $$$ if we so desired.
I really fail to see any valid excuse for not doing it. None whatsoever, in fact i am that one minded on the topic now, I could almost become adament we should do it.
For those who have not looked lately go here and have a read of what is actually ready for market, or almost ready.
http://www.microair.com.au/admin/upl..._Spec_Rev2.pdf
Cheers
J
Grandpa Aerotart
Tobzalp does that include Tiger Moths operating out of bumfeck Taswegia?
What about croppies at Wee Waa?
Sea Planes in the GBR marine park and Canadian wilderness?
Helicopers on trawlers?
Twin Otters, Islanders and cessna singles in the jungles of PNG, Africa and South America?
What about a privately owned Cessna 172 or Cherokee 180 that operates 99% of it's life in G airspace below 5000' miles from anywhere that has a Hicap RPT service...Iron Range for instance?
My Bonanza, which occassionally operates in Class C under an airways clearance and on a full flight plan has ADF,VOR,DME,GPS,Mode C and two transceivers...and now you're telling me I shold fit, at my own expence, equipment that costs somewhere close to 50-70% of the value of the actual aircraft so AsA can save millions...and for what again?
The airliners and ATC can already see me and talk to me... I don't exist to benefit the CEO of AsAs bank balance.
I think ADSB is great technology...it can save AsA huge money over many, many years while providing tangible safety benefits....but I'll be fecked if I am going to subsidise this Govt anymore than I do already.
What about croppies at Wee Waa?
Sea Planes in the GBR marine park and Canadian wilderness?
Helicopers on trawlers?
Twin Otters, Islanders and cessna singles in the jungles of PNG, Africa and South America?
What about a privately owned Cessna 172 or Cherokee 180 that operates 99% of it's life in G airspace below 5000' miles from anywhere that has a Hicap RPT service...Iron Range for instance?
My Bonanza, which occassionally operates in Class C under an airways clearance and on a full flight plan has ADF,VOR,DME,GPS,Mode C and two transceivers...and now you're telling me I shold fit, at my own expence, equipment that costs somewhere close to 50-70% of the value of the actual aircraft so AsA can save millions...and for what again?
The airliners and ATC can already see me and talk to me... I don't exist to benefit the CEO of AsAs bank balance.
I think ADSB is great technology...it can save AsA huge money over many, many years while providing tangible safety benefits....but I'll be fecked if I am going to subsidise this Govt anymore than I do already.
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Dick:
You say airline A/C should be fitted with TCAS when their capacity is 10-30 PAX. Isn't the current legislation 36+ requires TCAS? What happens to A/C between 31-35 PAX then? I am not being smart, I am genuinely interested in your campaign would like to know if what I thought was right, is actually wrong? I agree with you TCAS should be mandatory, bring on ADSB! You only need to do some research to the lives saved in Alaska in the past 12 months to show that this technology is a lifesaver. And not from a traffic perspective, more CFIT. Cheers!
BR
You say airline A/C should be fitted with TCAS when their capacity is 10-30 PAX. Isn't the current legislation 36+ requires TCAS? What happens to A/C between 31-35 PAX then? I am not being smart, I am genuinely interested in your campaign would like to know if what I thought was right, is actually wrong? I agree with you TCAS should be mandatory, bring on ADSB! You only need to do some research to the lives saved in Alaska in the past 12 months to show that this technology is a lifesaver. And not from a traffic perspective, more CFIT. Cheers!
BR
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Chuckles me old. 
In my part of the world where I guess maybe more than 60% of the hours and revenue is earned we mostly operate high performance aircraft (with TCAS) and gaggles of 19-30 seat Dash 8, Braz, Metro and B1900 (I expect with TCAS???) into often superb mining strips surrounded by many others in close proximity also populated by the charter 210's, 310's and Chieftains over and surrounded by the pastoral areas alive with mustering types in the season and the usual mix of C172 etc commuting into Karratha, Hedland Broome, Carnarvon for the mail and groceries.
And dont even get me started on the RPTs into Kalgoorlie, Broome et al.
All talking to Melbourne and Brisbane and each other and all arriving and departing within a 60 or so minute period at each end of the day.
No probs amongst themselves, it's the latterthe aircraft that puddle around in "G" 99% of the time that gets the pucker factor waaaaaay up there.
It looked for a while like they were going to get ADSB at a highly subsidised rate that would have solved ALL our problems but something happened along the way.
Now if you were to subsidise Transponders for these blokes, and they are a sight cheaper I suspect you would be a long way to home.
Which begs the question, what happened to the ADSB that I understood was the logical answer? I know we have had a long debate about it here but what was propsed seemed to make perfect sense to me for Australias unique aviation landscape. And I'm not talking about the J curve, its about the other 80% of Australia.
The US is a fair way along with NGATS.
http://www.faa.gov/news/updates/ADS-B/
and then there is this;
http://www.faa.gov/and/and500/500/do...Y_BULLETIN.pdf
Are newbies to this technology not in a solid structured mainline airline training system vis a vis the abovementioned FIFI operators going to need more training on TCAS than ADSB?
It seems there is no silver bullet.
In my part of the world where I guess maybe more than 60% of the hours and revenue is earned we mostly operate high performance aircraft (with TCAS) and gaggles of 19-30 seat Dash 8, Braz, Metro and B1900 (I expect with TCAS???) into often superb mining strips surrounded by many others in close proximity also populated by the charter 210's, 310's and Chieftains over and surrounded by the pastoral areas alive with mustering types in the season and the usual mix of C172 etc commuting into Karratha, Hedland Broome, Carnarvon for the mail and groceries.
And dont even get me started on the RPTs into Kalgoorlie, Broome et al.
All talking to Melbourne and Brisbane and each other and all arriving and departing within a 60 or so minute period at each end of the day.
No probs amongst themselves, it's the latterthe aircraft that puddle around in "G" 99% of the time that gets the pucker factor waaaaaay up there.
It looked for a while like they were going to get ADSB at a highly subsidised rate that would have solved ALL our problems but something happened along the way.
Now if you were to subsidise Transponders for these blokes, and they are a sight cheaper I suspect you would be a long way to home.
Which begs the question, what happened to the ADSB that I understood was the logical answer? I know we have had a long debate about it here but what was propsed seemed to make perfect sense to me for Australias unique aviation landscape. And I'm not talking about the J curve, its about the other 80% of Australia.
The US is a fair way along with NGATS.
http://www.faa.gov/news/updates/ADS-B/
and then there is this;
http://www.faa.gov/and/and500/500/do...Y_BULLETIN.pdf
Are newbies to this technology not in a solid structured mainline airline training system vis a vis the abovementioned FIFI operators going to need more training on TCAS than ADSB?
It seems there is no silver bullet.
Join Date: May 2005
Location: Brisbane
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tobzalp
Chuckles has a very good point. Those who operate out of site of anyone else dont benefit from it, but sooner or later that a/c makes a trip to the big smoke for whatever reason, and then to fit into the system with maximum effectiveness it should have the gear fitted.
Now, if the big end of town want "protection" from any source, be it ATC or a cockpit display, AND the folk at ASA can save heaps of money, why not subsidise the GA fit out. Its not for the GA benefit in the main, its the ASA and big boys that benefit, the little bugsmasher just has to carry it.
Simple Really......dont know why so many intelligent folk argue against it!
J
Chuckles has a very good point. Those who operate out of site of anyone else dont benefit from it, but sooner or later that a/c makes a trip to the big smoke for whatever reason, and then to fit into the system with maximum effectiveness it should have the gear fitted.
Now, if the big end of town want "protection" from any source, be it ATC or a cockpit display, AND the folk at ASA can save heaps of money, why not subsidise the GA fit out. Its not for the GA benefit in the main, its the ASA and big boys that benefit, the little bugsmasher just has to carry it.
Simple Really......dont know why so many intelligent folk argue against it!
J
Chuck, your type of aircraft should be the typical example for an aircraft owner who should be subsidised for fitment of ADS-B. The croppy at Wee Waa would be useful for a RAAFie on a LJR. GBR traffic can be busy around some destinations with both rotor and floaty ops. The trawler could have one of Dick's boxes and would know at a glance where the chopper is. The 180 just might benefit if the full low level coverage is rolled out. Last known position recorded could mean the difference if he drops off the system. AS a safety tool ADS-B has a lot going for it. The perceived security concerns are a sidetrack issue. No demonstration has ever been attempted to produce multiple false returns. The issue of knowing where an aircraft is has more benefits than risks. A radio scanner is just as dangerous in the terminal area.
Cost wise, the benefit rests solely with ASA. ASA saves the money by not having to refurb/replace radar heads. The rollout of ADS-B is cheaper by millions of real dollars even by subsidising basic equipment for all or a majority of GA aircraft. We get a safety benefit and ASA saves money and gets a modern expandable system.
I would like to here from the crews who have used the system in action to actually post their experience to let us less fortunate types know what we are missing out on. The more information that is out there, the better. It has now been over four or five months since YPWR(edit), BKE and LRE have been in operation. Surely there is someone here flying BN-PH or SY-DN who has benefitted from the extra coverage.
To answer the first post. Why bother forcing expensive equipment on one small part of the industry for a very narrow benefit when with the use of savings and subsidy everyone can get a benefit. If ASA would pay for a basic fitment I would definitely jump for a 480 or similar with a bit (A LOT)of my own money to top off the cost of fitment.
Gaunty, I have differing opinions to you on law and bureaucracy. However, I am 100% in agreeance in what you are saying. Life does not end fifty miles either side of the Hume. Not only your FIFOs and corporate iron but the RFDS also gets a massive operational benefit
Cost wise, the benefit rests solely with ASA. ASA saves the money by not having to refurb/replace radar heads. The rollout of ADS-B is cheaper by millions of real dollars even by subsidising basic equipment for all or a majority of GA aircraft. We get a safety benefit and ASA saves money and gets a modern expandable system.
I would like to here from the crews who have used the system in action to actually post their experience to let us less fortunate types know what we are missing out on. The more information that is out there, the better. It has now been over four or five months since YPWR(edit), BKE and LRE have been in operation. Surely there is someone here flying BN-PH or SY-DN who has benefitted from the extra coverage.
To answer the first post. Why bother forcing expensive equipment on one small part of the industry for a very narrow benefit when with the use of savings and subsidy everyone can get a benefit. If ASA would pay for a basic fitment I would definitely jump for a 480 or similar with a bit (A LOT)of my own money to top off the cost of fitment.
Gaunty, I have differing opinions to you on law and bureaucracy. However, I am 100% in agreeance in what you are saying. Life does not end fifty miles either side of the Hume. Not only your FIFOs and corporate iron but the RFDS also gets a massive operational benefit
Last edited by OZBUSDRIVER; 6th Feb 2007 at 10:38.
Grandpa Aerotart
I agree Gaunty...my point is that while ADSB would be most excellent it would only be most excellent for a small % of aircraft in Australia and would REALLY benefit AsA 'cause they could save several motzas on infrastructure...that only exists because of the requirements of the big end of town.
Maybe before we go down the road tobzalp suggests we could simply mandate that all aircraft capable of getting in anyones way should have a transponder fitted (that sqawks a callsign), tested annually...and hotwired to the battery bus along with the fecking beacon.
Anyone who fecks up sufficiently as to cause an airprox gets their licence ceremonially burnt in front of them and the ashes presented in a little urn with their (former) ARN engraved on it.
I think that would about fix it.
Maybe before we go down the road tobzalp suggests we could simply mandate that all aircraft capable of getting in anyones way should have a transponder fitted (that sqawks a callsign), tested annually...and hotwired to the battery bus along with the fecking beacon.
Anyone who fecks up sufficiently as to cause an airprox gets their licence ceremonially burnt in front of them and the ashes presented in a little urn with their (former) ARN engraved on it.
I think that would about fix it.