If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#111
|
|||
|
|||
"Andy Durbin" wrote in message om... "Paul Bart" wrote in message news:x2Gvc.4102 however given that GPS can *potentially* reduce an error, by up to 1000 ft it should be seriously considered. I wonder if the resistance to change is mainly due to the high average age of the gliding fraternity? Paul You seem to have missed the frequently stated point that the difference is not an error. An error free measurement of pressure altitude will not be equal to an error free gps (geometric) altitude except under rare conditions. No I did not. You are correct, I have incorrectly used the word error if one considers it's meaning in a relation to the output of the measuring device, however that was not my intention. Recognition of this fact may have something to do with age, but the real issues are recognizing what is to be measured, Height above ground I would have thought. If I understand the preceding discussion correctly, pressure altitude was used because there were no other viable options, not because it was a good measure of height above ground. why it is being measured, To either establish benchmark, or to fulfill some requirements. For each of these I would rather know the actual distance above ground, not a measure that depends on prevailing meteorological conditions. Unless, of course, you consider Martin's observation, that the effort to climb to a particular pressure altitude takes about the same effort regardless of the geometric altitude and also assuming that it is the effort that is important, rather then the actual height above ground. and then determining whether it is reasonable to change to measuring something else. Thank you for your observation. Paul |
#112
|
|||
|
|||
Have I got this right? We use barometric pressure to
measure altitude, difference in height, whatever. It actually measures pressure which has to be converted to height. We know that this 'measurement' will be inaccurate dependent on temperature and the pressure situation at the location, the amount of the accuracy is completely unknown. Two height diamonds gained on the same day at different locations will have to 'gain' different amounts of height. GPS measures the height above a known datum, with error correction the height readouts are the same everywhere, GPS measures the altitude in the units we use (Metres or feet), there is no conversion required. The question I am asking is why are we clinging on to and outdated and inaccurate system when a much more accurate system is available. We measure distance over the globe in feet or metres and happily use GPS for that, why do we not use it to measure the vertical directly distance as well? Perhaps we should revert to measuring in cubits At 09:54 04 June 2004, Paul Bart wrote: 'Andy Durbin' wrote in message . com... 'Paul Bart' wrote in message news: however given that GPS can *potentially* reduce an error, by up to 1000 ft it should be seriously considered. I wonder if the resistance to change is mainly due to the high average age of the gliding fraternity? Paul You seem to have missed the frequently stated point that the difference is not an error. An error free measurement of pressure altitude will not be equal to an error free gps (geometric) altitude except under rare conditions. No I did not. You are correct, I have incorrectly used the word error if one considers it's meaning in a relation to the output of the measuring device, however that was not my intention. Recognition of this fact may have something to do with age, but the real issues are recognizing what is to be measured, Height above ground I would have thought. If I understand the preceding discussion correctly, pressure altitude was used because there were no other viable options, not because it was a good measure of height above ground. why it is being measured, To either establish benchmark, or to fulfill some requirements. For each of these I would rather know the actual distance above ground, not a measure that depends on prevailing meteorological conditions. Unless, of course, you consider Martin's observation, that the effort to climb to a particular pressure altitude takes about the same effort regardless of the geometric altitude and also assuming that it is the effort that is important, rather then the actual height above ground. and then determining whether it is reasonable to change to measuring something else. Thank you for your observation. Paul |
#113
|
|||
|
|||
|
#114
|
|||
|
|||
I'm new on this forum, and this thread has captured my attention because the theme is really popular in the gliding world. So I'll try to give my opinion on a number of posts I read. It always strikes me as odd that we fumbled with cameras and expensive barographs, plus the problems of sealing them and finding an Official Observer, for all these years without complaining, and that the whole gliding world now seems to resent the approved loggers just for being more costly than the typical off-the-shelf GPS. My barograph cost me about half the price of my Volkslogger, but with the 20 years difference in time, even with modest inflation rates, I think the price is not that far off. And indeed, finding an OO is still often the hardest part of the administrative burden. Luckily it's only necessary for badge flights, if you are using an approved FR. I don't now if you have decentralized contests in Oz, like the OLC in Europe. For this kind of flights, who are certainly as interesting as badge flights, the use of an approved FR allows one to be completely free of paperwork and OO's. In most European countries, this freedom has done much more for the generalization of cross-country flying than the badge system itself. In Flanders (Belgium) where I live, when I come home, I download my flight from the logger, upload it to the Flemish contest website, the program checks the validity and respect of airspace, calculates the points and classifies it in the correct class. Done! I can check in real time how I did in comparison with others today. In France, you can use some non-approved loggers in their NetCoupe, but because of that, the system is much less automatic, and for non-approved loggers you need indeed paperwork and an OO. I much prefer the Flemish system, even if I was obliged to get an approved FR. All clubs here have one or two FR's for rent to their members, some have one per club glider. I've read somewhere in this thread that because of different club systems between Europe and Oz / USA, it would be impractical to have the clubs buying FR's and renting them to their members. This seems rubbish to me: if a club can buy and rent something as expensive as a glider with radio, parachute, trailer etc., surely a FR can't make much difference. And I suppose it has always been done with barographs, just like here. Or does everybody have to buy his own to fly for badges? I agree that the "data security" aspect seems a bit overdone at IGC, but that's no reason to be verbally aggressive against the people who developed the norms: they are not "self-appointed geeks", as one writer put it. Geeks they may be, I don't know them personally, but as so often in gliding, they probably are the people who volunteered to do the job. Having been rather active as volunteer for lots of little and bigger jobs on club, regional and national level, it strikes me that there are very few people who agree to spend much time in doing things like studying lots of documents, participating in conferences, workshops, meetings... instead of flying. But when decisions are made by these few (always the same, hence the accusation of "oligarchy", "self-appointed", etc.), lots of people start to question them. I don't think that's fair. I sure as hell don't agree with everything IGC decides, but I write to my delegate, assemble petitions, etc., if I think it's really worth it. Just discussing it on a forum doesn't help. So if you want to get cheaper GPS units to be used for badge flights, you'll have to do some serious lobbying work. And prepare yourself to become OO, because you'll find your club needs more of them. I don't now how it works in other countries, but here it means passing an examination and following an (almost) annual refresher course. So! Now you have another pianist to shoot at. Fire away! -- stephanevdv ------------------------------------------------------------------------ Posted via OziPilots Online [ http://www.OziPilotsOnline.com.au ] - A website for Australian Pilots regardless of when, why, or what they fly - |
#115
|
|||
|
|||
"Paul Bart" wrote in message ...
Recognition of this fact may have something to do with age, but the real issues are recognizing what is to be measured, Height above ground I would have thought. If I understand the preceding discussion correctly, pressure altitude was used because there were no other viable options, not because it was a good measure of height above ground. Without any effort I can identify 3 different measurements that are curently derived from pressure based barographs and flight recorders. They a continuity of flight altitude gained following a low point absolute altitude achieved Height above ground is not a parameter that is used for any badge, award, or record as far as I know. Please don't interpret my reply as being an objection to COTS GPS. If ever there was an opportunity to change the world from pressure altitude to GPS altitude it was when RVSM was introduced. But no, many aircraft faced expensive air data system retrofits because the system was too enrenched in barometric altimetry. Andy |
#116
|
|||
|
|||
|
#117
|
|||
|
|||
X-no-archive: yes
In article , stephanevdv writes I'm new on this forum, and this thread has captured my attention because the theme is really popular in the gliding world. So I'll try to give my opinion on a number of posts I read. Welcome to the wonderful world of RAS! It always strikes me as odd that we fumbled with cameras and expensive barographs, plus the problems of sealing them and finding an Official Observer, for all these years without complaining, and that the whole gliding world now seems to resent the approved loggers just for being more costly than the typical off-the-shelf GPS. My barograph cost me about half the price of my Volkslogger, but with the 20 years difference in time, even with modest inflation rates, I think the price is not that far off. And indeed, finding an OO is still often the hardest part of the administrative burden. Luckily it's only necessary for badge flights, if you are using an approved FR. I don't now if you have decentralized contests in Oz, like the OLC in Europe. For this kind of flights, who are certainly as interesting as badge flights, the use of an approved FR allows one to be completely free of paperwork and OO's. In most European countries, this freedom has done much more for the generalization of cross-country flying than the badge system itself. In Flanders (Belgium) where I live, when I come home, I download my flight from the logger, upload it to the Flemish contest website, the program checks the validity and respect of airspace, calculates the points and classifies it in the correct class. Done! I can check in real time how I did in comparison with others today. An interesting point. While there has been considerable discussion about the use of Pressure Altitude Vs GPS Altitude, the vertical limits of Airspace are expressed in terms of Pressure Altitude, which is unlikely to change any time soon. ---snip-------------- I agree that the "data security" aspect seems a bit overdone at IGC, It may seem that way, but one objective is to avoid having the revise the level on an annual basis, which could imply annual updates to recorders at the owners expense. Better to set it higher and wait for technology to catch up. but that's no reason to be verbally aggressive against the people who developed the norms: they are not "self-appointed geeks", as one writer put it. Geeks they may be, I don't know them personally, but as so often in gliding, they probably are the people who volunteered to do the job. Having been rather active as volunteer for lots of little and bigger jobs on club, regional and national level, it strikes me that there are very few people who agree to spend much time in doing things like studying lots of documents, participating in conferences, workshops, meetings... instead of flying. But when decisions are made by these few (always the same, hence the accusation of "oligarchy", "self-appointed", etc.), lots of people start to question them. I don't think that's fair. There is much truth on what you say. I sure as hell don't agree with everything IGC decides, but I write to my delegate, assemble petitions, etc., if I think it's really worth it. Just discussing it on a forum doesn't help. So if you want to get cheaper GPS units to be used for badge flights, you'll have to do some serious lobbying work. And prepare yourself to become OO, because you'll find your club needs more of them. I don't now how it works in other countries, but here it means passing an examination and following an (almost) annual refresher course. Considering the issue of COTS units, almost all of the invective has been directed against the Flight Recorder Specification which currently prohibits them. However, I am of the opinion that changing the Specification is not the correct route to take. The specification should remain 'as is' for approved units above whatever level is deemed the appropriate ceiling for COTS. To change the specification to allow COTS also implies that each Make/model has to be submitted for approval, which would be an impossible task. What needs to be changed is the wording in the Sporting Code to allow COTS to be use up to a specific level (e.g. Gold C) and an approved Flight Recorder thereafter. So! Now you have another pianist to shoot at. Fire away! Join the club! Best regards, Tim Newport-Peace "Indecision is the Key to Flexibility." |
#118
|
|||
|
|||
A couple of thoughts:
"stephanevdv" wrote in message ... It always strikes me as odd that we fumbled with cameras and expensive barographs, plus the problems of sealing them and finding an Official Observer, for all these years without complaining, and that the whole gliding world now seems to resent the approved loggers just for being more costly than the typical off-the-shelf GPS. My barograph cost me about half the price of my Volkslogger, but with the 20 years difference in time, even with modest inflation rates, I think the price is not that far off. On the other hand, we now have the chance to use truly cheap units that cost less than a quarter of your Volkslogger and which can be viewed, tried out, etc. at your local camping supply store. I think that's what the real hue and cry is about. Not only that, you can then take that same COTS unit and use it to navigate to aunt Susie's house in your car or to go out and locate your favorite fishing hole in your boat. Try that with your smoked foil barograph. In Flanders (Belgium) where I live, when I come home, I download my flight from the logger, upload it to the Flemish contest website, the program checks the validity and respect of airspace, calculates the points and classifies it in the correct class. Done! I can check in real time how I did in comparison with others today. In New Jersey (USA) where I live, I can come home and dowload my GPS76 trace and upload it to the Governor's Cup website. I don't need to validate anything, because we use an honor system for the flight since there's really not a whole lot at stake . . . I agree that the "data security" aspect seems a bit overdone at IGC, but that's no reason to be verbally aggressive against the people who developed the norms: they are not "self-appointed geeks", as one writer put it. That's the risk we all face in taking on a job like the GFAC. I'm pretty sure that Ian, Tim, and the rest don't lose tons of sleep over this forum. I know I don't when folks object to things I do in the Governor's Cup or when I was president of a local Soaring Club. On the other hand, I sure hope that they, and the other IGC folks who lurk in the shadows can sense the fact that this is a very hot topic. One positive thing that has happened in this thread is that a number of issues have crystallized and been open to view to the entire world. My biggest complaint with the GFAC (which I have conveyed directly, privately to the GFAC members with whom I have corresponded) is that there is no visibility to exactly HOW the committee works and what the driving objectives are. The main answer I've received to date is that the GFAC exists to serve the standards as currently written ( I don't mean it to sound sarcastic - it's not intended that way) E.G. "Why do we have to use Pressure Altitude - because the standard says so? " I think the GFAC and IGC would do themselves a great service if there were minutes or at least position papers that explained the rationale BEHIND various decisions. I for one intend to publish a position paper that radically challenges the fundamental assumptions behind the current standards and will request that the IGC and GFAC come back with a formal response.. I sure as hell don't agree with everything IGC decides, but I write to my delegate, assemble petitions, etc., if I think it's really worth it. Just discussing it on a forum doesn't help. So if you want to get cheaper GPS units to be used for badge flights, you'll have to do some serious lobbying work. And prepare yourself to become OO, because you'll find your club needs more of them. I don't now how it works in other countries, but here it means passing an examination and following an (almost) annual refresher course. Bingo. I realilzed that about 2 weeks ago, and that's definitely where I'm going. So far, I've lined up objective data by polling a large club organization to find out exactly what GPS equipment already exists in the hands of pilots (60% in this club actually own a COTS logger, somewhat surprisingly), am in the process of polling the US State Governors and Record Keepers to get inputs on direction (so far about 75% in favor of actively pushing COTS for badges), and am putting together a formal position paper (no not a proposal) which will state that we should aggressively pursue unmodified COTS (thus adhering to the spirit of "OTS"). I would love to enlist others in the US to sign up for pro-COTS organization to work with all of the SSA directors to convince them to push our IGC representative in that direction. I would love to see the same happen in other countries. But yes, the only way to make things change is to work up the chain of command. That is both a price and a protection of these types of organizations, which I think is one of the biggest takeaways from this whole thread. I also would recommend that people who feel strongly enough about this make it an issue for their local soaring organization representatives. I think for example, if the folks in Sweden, Australia, and Poland (to pick three places where I know that there are active COTS movements) made this the primary issue for their directors and met with their IGC reps, I think things would start to move much more rapidly. So! Now you have another pianist to shoot at. Fire away! Welcome to the club :-)) -- stephanevdv ------------------------------------------------------------------------ Posted via OziPilots Online [ http://www.OziPilotsOnline.com.au ] - A website for Australian Pilots regardless of when, why, or what they fly - |
#119
|
|||
|
|||
Todd Pattist wrote:
stephanevdv wrote: [discussing OLC contests] the use of an approved FR allows one to be completely free of paperwork and OO's. In most European countries, this freedom has done much more for the generalization of cross-country flying than the badge system itself. I agree that OLC contests are a great motivator, but I don't see why approved FR's need to be used there either. Here are the requirements for different national OLCs (copy from the info&rules page): olc land validated igc-files required approved igc-FR required olc-af Africa N N olc-ar Argentina N N olc-at Austria J J olc-au Australia N N olc-be Belgium N N olc-br Brazil N N olc-ca Canada N N olc-ch Switzerland J J olc-cz Czech-Rep./Slovakia N N olc-d Germany J J olc-dk Denmark J J olc-es Spain J J olc-fi Finland N N olc-fr France N N olc-gr Greece N N olc-hu Hungary N N olc-i International J J olc-it Italy J J olc-jp Japan N N olc-lu Luxembourg J J olc-mo Aeromodelling N N olc-nl Netherlands N N olc-no Norway N N olc-nz New Zealand N N olc-pl Poland N N olc-pt Portugal N N olc-se Sweden N N olc-si Slovenia N N olc-uk United Kingdom N N olc-usa USA N N olc continent validated igc-files required approved igc-FR required olc-kaf Africa J J olc-kaq Antarctika J J olc-kar Arctika J J olc-kas Asia (Near East, East, all Asia) J J olc-kau Australia and Oceania J J olc-keu Europe J J olc-kna North America J J olc-ksa South America (Latin America, Middle and Caribic) J J olc-kw World (Panet Earth) J J Shall we treat it as a votes for COTS? /Janos |
#120
|
|||
|
|||
On Mon, 07 Jun 2004 10:09:58 -0400, Todd Pattist
wrote: Tim Newport-Peace ] wrote: What needs to be changed is the wording in the Sporting Code to allow COTS to be use up to a specific level (e.g. Gold C) and an approved Flight Recorder thereafter. Agreed. I'd let the O.O have the responsibility for verifying compliance of the GPS with a bare minimum list of required GPS features , and provide a list of COTS GPS units known to meet those standards: as in "Capable of recording time and position fixes according to WGS 84," etc. It would be simpler for all concerned if the pilot is required to demonstrate compliance with the (published) list of required features to the OO. Benefits: - the pilot has a checklist to use when buying the GPS - the OO doesn't have to understand the GPS and its documentation in the detail needed to verify compliance A demerit that nobody has yet mentioned is that of the poor suffering OO having to understand a multitude of GPS and download programs. -- martin@ : Martin Gregorie gregorie : Harlow, UK demon : co : Zappa fan & glider pilot uk : |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
us air force us air force academy us air force bases air force museum us us air force rank us air force reserve adfunk | Jehad Internet | Military Aviation | 0 | February 7th 04 04:24 AM |