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#31
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"Rory O'Conor" wrote in message ... Mid Air collisions are a problem. Maybe we need to pull together more information about them. There are a number of different phases of flight during which they occur: Climbing phase (high Angle of Attack) (power planes only) Circuit phase (all planes) Aerobatics (all planes) IFR & low visibility flight (all planes) Normal flight (all planes) Thermalling (soaring planes only) We need to understand the proportion of collisions occurring in the different phases and the potential contributory factors. Road Traffic Accidents happen more often in good weather than bad. It is not entirely clear that thermal collisions happen more often in competition gaggles than when there are only two in a thermal, whatever our instincts. For the different flight phases, different factors will be more or less important and the solutions and devices to prevent collisions may be different. Personnally I would be surprised if TCAS devices could cope with resolving the trajectories of thermalling gliders other than the basic level of identifying another nearby plane. Thus I suspect that the main detection instrument in thermals remains the eyeball. In which case, every effort should be made to ensure the best use of the eyeball in thermals. There may be a role for such devices in other phases eg normal flight and IFR. The only power planes that regularly fly close together are the military and aerobatic display teams. I am sure that the Red Arrows are fitted with the instruments that they best require, but I would be most surprised if they have any electronic device warning them that they are about to hit a team-mate. I expect that they do a lot of training, have superb lookout and excellent communications. I would assume that a TCAS/GPS device will be making noises at 1 mile and probably very loud noises at 1/4 mile (1500 ft). With a typical thermalling diameter of 200-600 feet and circling period of less than 20 seconds, any normal TCAS would be screaming fit to be turned off! We are also entering the area where the margin of error for a GPS (30 ft horizontally, 100 ft vertically) is a significant issue. GPS is not accurate enough to tell which side of the highway you are driving on, nor probably to determine the correct seperation of two thermalling gliders when the pilots using their eyeballs consider that they are adequately seperated. I cannot envisage an electronic GPS device for avoiding intra-thermal collisions, assuming that the planes are going to remain in the same thermal. Rory And yet another.... Bill Daniels |
#32
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"Dave Martin" wrote in message ... This is what it boils down to EDUCATION/TRAINING Training pilots how to look out. How to concentrate, What the dangers are, real and perceived and potential and where these danger lurk in a particular phase of flight. We will never eliminate accidents but by education we can reduce the opportunities. Train hard fly easy as some one said! Dave At 17:00 30 April 2004, Rory O'Conor wrote: Mid Air collisions are a problem. Maybe we need to pull together more information about them. There are a number of different phases of flight during which they occur: Climbing phase (high Angle of Attack) (power planes only) Circuit phase (all planes) Aerobatics (all planes) IFR & low visibility flight (all planes) Normal flight (all planes) Thermalling (soaring planes only) We need to understand the proportion of collisions occurring in the different phases and the potential contributory factors. Road Traffic Accidents happen more often in good weather than bad. It is not entirely clear that thermal collisions happen more often in competition gaggles than when there are only two in a thermal, whatever our instincts. For the different flight phases, different factors will be more or less important and the solutions and devices to prevent collisions may be different. Personnally I would be surprised if TCAS devices could cope with resolving the trajectories of thermalling gliders other than the basic level of identifying another nearby plane. Thus I suspect that the main detection instrument in thermals remains the eyeball. In which case, every effort should be made to ensure the best use of the eyeball in thermals. There may be a role for such devices in other phases eg normal flight and IFR. The only power planes that regularly fly close together are the military and aerobatic display teams. I am sure that the Red Arrows are fitted with the instruments that they best require, but I would be most surprised if they have any electronic device warning them that they are about to hit a team-mate. I expect that they do a lot of training, have superb lookout and excellent communications. I would assume that a TCAS/GPS device will be making noises at 1 mile and probably very loud noises at 1/4 mile (1500 ft). With a typical thermalling diameter of 200-600 feet and circling period of less than 20 seconds, any normal TCAS would be screaming fit to be turned off! We are also entering the area where the margin of error for a GPS (30 ft horizontally, 100 ft vertically) is a significant issue. GPS is not accurate enough to tell which side of the highway you are driving on, nor probably to determine the correct seperation of two thermalling gliders when the pilots using their eyeballs consider that they are adequately seperated. I cannot envisage an electronic GPS device for avoiding intra-thermal collisions, assuming that the planes are going to remain in the same thermal. Rory We've trained and trained for 100 years and yet we still have collisions. The 'Mark 20 eyeball' is a good tool but it isn't the total solution. Humans just can't maintain the vigilance required. We have plenty of evidence of that both clinical and anecdotal. Bill Daniels |
#33
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I'm surprised people still beleive that eyes are better than
electronic equipment. Consider the following: 1 - You don't see behind and below, and even forward visibility is somewhat restricted, depend on cockpit style. 2 - We fly invisible aircrafts. Did you notice how quickly a sailplane disappears when it flies away? If you stand on a runway behind a launching glider it almost disappears before it reaches the end of the runway, this is less than a mile! 3 - While you can notice planty of aircrafts flying nearby, the ones on a direct collision course are the hardest to detect since they look stationary relatively to you! I once barely noticed while thermaling a strange stationary dot in the sky and wondered what was it, the next turn it turned into an airliner heading directly to me and I had to perform an evasive maneuver! Since then I am flying with a transponder and never saw an airliner nearby again. 4 - The above gets even more difficult if not impossible to detect when the threat is flying perpendicular to you. 5 - The main reason why we don't colide with other aircrafts more often is simply the fact that the sky is (still) big and the chance that 2 aircrafts will occupy the same 4 dimensions is rare. Ramy Dave Martin wrote in message ... At 05:12 30 April 2004, Graeme Cant wrote: Dave Martin wrote: Whatever happened to teaching good look out and airmanship? Nothing. It's still taught and practiced as effectively, efficiently and thoroughly as it ever was - and has been for many years. And it's just as ineffective as it ever was. Are you one of those who see it as simply a problem of laziness and complacency? You're probably right but they're both endemic in human nature and won't change now. For jobs as important as this, monitoring systems designed with built-in tendencies to distraction and complacency and with multiple duties just to top it off - are simply inadequate and always will be. All forms of training in lookout are doomed to fail because of basic human limitations. Not just optical limitations. Humans are simply bad at continuous alertness and monitoring for a very low probability threat over a long period. That's why we no longer have engineer's panels in the flight decks of large aeroplanes. There's as much or more to monitor than there always was - we've just accepted that humans don't do it well and found other solutions. Gliders have the highest rate of midairs of all forms of hard wing aviation. I'm happy with the collision threat and the things I do to minimise it and I'll go on flying gliders. If you're not happy, Dave, you need to accept that it won't be improved without electronic assistance. Isn't 50 or more years enough? Graeme Cant Graeme Where did I say I wasn't happy with the present situation ? Adding an electronic device will not ease the problem, in the majority of cases it could compound the problems faced by the average pilot. Large aircraft do not fly in close proximity to others in great numbers such as a thermal gaggle. They also have such things as transponders, outside radar support from control towers and other sophisticated equipment plus the electronic power to support all the devices. In the main they fly in regulated airspace, where everyone has the same equipment Flying in isolation such a device may help but in crowded skies I suspect the information supplied would overload the equipment and pilot, as you say above, 'Humans are simply bad at continuous alertness and monitoring for a very low probability threat over a long period.' How does this equate with a large competiton gaggle who must monitor high probability threats over long periods say several hours and during their flight will meet others not in their competition on their flight path. I suppose someone will say they train for this type of flying. Fitting units to gliders in isolation will also give the pilot a false sense of security. You ask, 'Isn't 50 or more years enough?' 1 year is too long! Dave |
#34
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We've tried "look out the window." We still have collisions. Since
human capabilities change only over evolutionary time, and training programs that encourage good use of existing capabilities have been in place for some time, we should assume that training and exhortations have achieved as much improvement as they ever will. The remaining collision risk must be reduced through some other means. The traffic pattern and thermals are two high-density traffic environments where aircraft maneuvering renders collision prediction difficult. It's not just difficult for machines, it's also difficult for pilots. During pilot training the task must be taught in several steps: 1) be aware of how many other aircraft are nearby 2) locate them 3) avoid getting close to those aircraft unless necessary 4) if proximity is necessary, watch (i.e., try to predict) the path of the other aircraft and avoid going toward the place where it is going 5) learn to anticipate possible unpredictable variations in the path of the other aircraft also and avoid going toward those areas. Level 5) is probably only required in thermals and in formation flying. When we begin thermaling, most of us have to use 3) because we're not good enough at 4) or 5). However, at the moment pilots are much better than machines at 4) and 5), while machines are much better than pilots at 1) and 2). Yet, if 1) fails, the rest is useless. The fact that machines can't do the whole job does NOT mean they can't be helpful. A machine that could inform a pilot that there are 5 other aircraft in the thermal within +/- 500 ft would be valuable to a very alert contest pilot who could account for only 4 of them. The tasks of finding the 5th, and avoiding all 5, might still have to rely on the Mark I Eyeball. Of course, pilots in gaggles know that they are in a high collision-risk situation, and they devote significant attention to seeing and avoiding other aircraft. Pilots who think they are alone in the sky devote much less mental capacity to those tasks. Insisting on "always" maintaining lookout vigilance is ill-advised: many of us have a pretty high cognitive load a high percentage of the time in flight, and if we devote too much attention to lookout we may well lose navigational or meteorological situational awareness, or even just tire ourselves out mentally, leaving ourselves vulnerable when attention is important later. This is where a machine could help, by maintaining a scan and verifying that, indeed, the collision risk is low. If that changes, the machine can alert the pilot, allowing the pilot to properly switch mental capacity to "see and avoid." In fact, this is the primary benefit of flight following during powered VFR flight, and it's no small benefit. Insisting that a technology is useless unless it can solve the whole problem makes perfection the enemy of the good. It's also, in this case, blind to the imperfection of the current technology - the Mark I Eyeball - which plenty of science has shown is, in most near-miss scenarios, far less valuable than the sheer size of the sky. |
#35
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#36
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Mike,
The FLARM concept has been painfully obvious, from a technology point of view, since the introduction of low-cost GPS. In fact, it could even have been partially implemented with LORAN, but those receivers were expensive and were never widely deployed. Unfortunately, FLARM-type collision avoidance is only going to work if it's deployed to virtually all aircraft, which would require the authorities to insist on it. This won't happen: ADS-B is the chosen approach. It seems to me that TIS-B is most likely what will first begin to provide us with the functionality we need - and actually get deployed. TIS-B (Traffic Information Service - Broadcast) is a portion of ADS-B, essentially a broadcast of the radar returns seen by ATC. At the moment it has limited coverage in the US but you can receive it - however you need to spend about $15,000 on avionics including a Mode S transponder plus a display unit designed for bigger panels than we have. Still, no doubt it will soon occur to some entrepreneur that a TIS-B receiver without all the Mode S baggage, designed for display on a PDA might well find a market (lots of Cezzna drivers think $15k is a lot of money too). |
#37
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Don Johnstone wrote: The answer is, good lookout, good situational awareness and the ability to put safety first, press on itius second. This doesn't sound like an answer to me. I do all those things, yet I've still come close to collisions. Don't expect the other guy to get out of your way, get out of his, and if that means he has an advantage, sobeit, at least you continue to fly on intact. I don't expect the other guy to get out of my way, but I've still come close to collisions. These have generally been contest situations involving many gliders, but not always. An effective, but not perfect, way to avoid collsions is to always fly well away from other gliders. It's not a perfect way, because you can't stop other glider from seeing you and joining you. I'm surprised people are willing to claim a technological solution is unworkable without any demonstration of it's ability. How can you say "The answer is, good lookout, good situational awareness and the ability to put safety first, press on itius second", when you have no data on the proposed solution? Wouldn't a better remark be "Try it, and show us the results?" -- Change "netto" to "net" to email me directly Eric Greenwell Washington State USA |
#38
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In a recent mid air in the UK it was a quiet day, bright and hazy with poor
visability. There were only 3 or 4 aircraft in the air at the same time. Percieved low risk of collision so level of lookout was low? A very experienced (10,000+ hrs in gliders) was killed. |
#39
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Anti-collision warnings
Once again a thread on RAS has polarised neatly into two camps Argument 1. The mark 1 eyeball and the USB (Universal Standard Brain) are the best! Train them and the problem is solved. Argument 2 Statistics show the above equipment is outdated for present needs it needs replacing or providing with some assistance. OK. Accept that at present theory 1 is the best we have come up with so far and that change is needed. The challenge is now how to assist the brain solve the problem. Individuals are not the probelm, it is everyone else out there who is trying to get you. Remember it is the aircraft you do not see that gets you! So all we need is a simple instrument that meets the following criteria. 1. It will detect at least 40 gliders in close proximity. 2. Plus those within a 5 nautical mile range. 3. Work out their relative positions. 4. Assess the collision threat of each and every one. 5. Feed the information to the pilot of each glider in a readable format that can be assessed within the bat of an eyelid. 6. Develop the instrument with little financial assistance from within the movement. 7. Ensure every glider has the equipment fitted. 8. Ensure the equipment works with very little power consumption. 9. Ensure that the cost is no more that a launch fee. 10. Make fitting compulsary to ALL aircraft flying in uncontrolled airspace. No one who fits any form of instrument to his glider can be accused of being anti progress. BUT until the above problems are more than half solved the practicalities of a succesfull anti collision device are low. In he mean time I return to argument 1. At present this is the best we have! If technology comes up with a reliable assistant this must be good until then WE MUST ensure that our pilots are trained on the dangers that lurk out there. Dave |
#40
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Who are you, OscarCVox? Why the nickname?
Where do you fly? W.J. (Bill) Dean (U.K.). Remove "ic" to reply. Talgarth, Nympsfield, Mynd, formerly Lasham for over 20 years. "OscarCVox" wrote in message ... In a recent mid air in the UK it was a quiet day, bright and hazy with poor visibility. There were only 3 or 4 aircraft in the air at the same time. Perceived low risk of collision so level of lookout was low? A very experienced (10,000+ hrs in gliders) was killed. |
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