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#1
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Mangling of U.S. Contest Flight Logs?
I was recently asked to contribute some flight log analyses for an upcoming presentation by John Mittell for his club on his first-time competitor experience at the Seniors. I downloaded flight logs from the SSA site and started going through them in See You, and I noticed that thermals looked very funny. Instead of pentagons or hexagons or circles, I was seeing jagged back-and-forth lines. I looked at the fix times in SeeYou and discovered that fixes were 12 sec apart instead of 4 sec (or 1 sec for some ClearNav files), making thermals basically impossible to analyze, and causing See You to badly miscalculate average climb rates. When I looked directly at the IGC files with a text reader, I saw the following note embedded in the file:
LXXX LXXX Note: This IGC file has been condensed by Winscore for Internet spectators. LXXX Contact the contest organizers for the complete version of this file. LXXX (The complete version was used for contest scoring calculations..) LXXX In this day and age of ubiquitous high-speed internet, this makes little sense, and compression to this degree makes them completely useless for their intended purpose - i.e. making them available to other interested parties for education and training purposes. I'm not sure who to approach about this, but how do we get this policy of deliberate filicide (my new word for the day) reversed? Frank (TA) |
#2
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Mangling of U.S. Contest Flight Logs?
On Monday, 26 March 2012 19:02:01 UTC-6, wrote:
I was recently asked to contribute some flight log analyses for an upcoming presentation by John Mittell for his club on his first-time competitor experience at the Seniors. I downloaded flight logs from the SSA site and started going through them in See You, and I noticed that thermals looked very funny. Instead of pentagons or hexagons or circles, I was seeing jagged back-and-forth lines. I looked at the fix times in SeeYou and discovered that fixes were 12 sec apart instead of 4 sec (or 1 sec for some ClearNav files), making thermals basically impossible to analyze, and causing See You to badly miscalculate average climb rates. When I looked directly at the IGC files with a text reader, I saw the following note embedded in the file: LXXX LXXX Note: This IGC file has been condensed by Winscore for Internet spectators. LXXX Contact the contest organizers for the complete version of this file. LXXX (The complete version was used for contest scoring calculations.) LXXX In this day and age of ubiquitous high-speed internet, this makes little sense, and compression to this degree makes them completely useless for their intended purpose - i.e. making them available to other interested parties for education and training purposes. I'm not sure who to approach about this, but how do we get this policy of deliberate filicide (my new word for the day) reversed? Frank (TA) There is a parameter in WINSCORE that allows the scorer, when up loading IGC files, to compress them and to specify the minimum time between fixes. The scorer can re-upload if they so desire, have a better internet connection and have the time. Last time I was at Seminole "ubiquitous high-speed" access was not available, rather they only have satellite based internet access. Many rural areas do not have the same access to the internet as you city folks. You are jumping to conclusions and implicating hard working volunteers. There is not deliberate conspiracy issues occurring here. Take off your tainted, rose colored glasses and try to understand reality and stop beating on the volunteers that make competitions happen. Ron Gleason |
#3
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Mangling of U.S. Contest Flight Logs?
I agree file compression is silly in this case.
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#4
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Mangling of U.S. Contest Flight Logs?
Ron,
Hey, thanks for the information, and the personal attack - I haven't gotten that kind of rise out of anyone since I since last year, when I was censored at your Logan mountain-survival contest for using the U word ;-). Lets see: The zipped file size for March 16 was 655KB, which represents about 10-15 seconds at normal DSL rates (500-1000Kbs upload speed). With un-mangled files, the upload, done once per day, would have taken about 3 times longer, or about 45 seconds. Stop me when I go off track here, but I fail to see the advantage of saving 30 seconds (or even 3 minutes)/day while rendering ALL the files essentially useless for analysis. The Seniors stopped using satellite-based internet connectivity several years ago, but we still have problems with slow connections there when everyone tries to get on at once. Many of us have started using the Ubiquitous (another U word!) USB cell modems - my Verizon USB modem cost me all of $50 for 1GB data with DSL-or-better upload/download rates. However, even on bad days at the Seniors, I'm not really sure how the difference between 15 seconds and 45 seconds of upload time on a once/day basis would be significant. The scoring at this year's Seniors was done by Florin Alexandrescu. This post was not, and is not, any reflection on the superb job he did, especially for a first-time scorer. It is, however, a call to stop compressing IGC files to the point of unusability in an attempt to save an insignificant amount of internet upload time. I would be more than happy to use my own USB modem bandwidth for this purpose at any contest I attend - just ask ;-). Frank (TA) There is a parameter in WINSCORE that allows the scorer, when up loading IGC files, to compress them and to specify the minimum time between fixes. The scorer can re-upload if they so desire, have a better internet connection and have the time. Last time I was at Seminole "ubiquitous high-speed" access was not available, rather they only have satellite based internet access. Many rural areas do not have the same access to the internet as you city folks. You are jumping to conclusions and implicating hard working volunteers. There is not deliberate conspiracy issues occurring here. Take off your tainted, rose colored glasses and try to understand reality and stop beating on the volunteers that make competitions happen. Ron Gleason |
#5
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Mangling of U.S. Contest Flight Logs?
If you want a change made document it and submit it to the rules committee prior to October of each year.
The WIINSCORE Users Manual for 2011 can be found here http://www.gfbyars.com/winscore/Winscore%20User's%20Guide.pdf Go to page 40 for the guidelines in the manual for uploading IGC files. Here is a paragraph from that section Minimum time between fixes - Typically, flight data recorders save a fix at 4 second intervals. However, if the .zip file contained every fix that each pilot made for the entire day, the .zip would be too large to send efficiently. Therefore, the scorer can set a new time interval that is used to create the .zip. If the time interval entered here is larger than what the pilot used during his flight, then some of his fixes will be ignored when his flight is put into the .zip. Using a short interval will give more detail to the Internet viewer, but will increase the .zip size and using a longer interval will give less detail to the internet viewer, but will decrease the .zip size. Testing has show that a 15 second interval to be a good tradeoff between resolution and file size. Whining on RAS does not necessarily get things changed, in my experience. Ron |
#7
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Mangling of U.S. Contest Flight Logs?
Whining on RAS does not necessarily get things changed, in my experience. Ron No, but it's sometimes a good place to find out WHO to complain to. :-) |
#8
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Mangling of U.S. Contest Flight Logs?
I agree with you, Frank, in that I would like to see the whole flight,
as logged. And that there is likely little time saved by having Winscore "reduce" the file sizes. But, how badly is the climb rate mis-calculated by dropping some data points? Unless the climb is just a turn or two, where the climb rate could have been mostly the zoom entrance, are you really losing much? What matters is bottom to top, unless you are trying to show "He shifted over a bit here, and look how much faster he went up." In that case, can you tell the shift from the drift? And if what you are intersted in is bottom to top, if you have the end points, do you lose anything by not having the middle? I can see value in showing "Thermal started to drop off here, so you should have left and not taken the next three turns." But, even at 15 seconds between samples, this would still be apparent. Less points around the turn will also damp out the zooms and dives some pilots make when thermalling, thus actually giving you a better indication of actual climb rate. Note to scorers: Please look at Winscore and set it up so the zip file it creates will go ahead and keep more of the data points. Help keep Frank happy. And a lot of the rest of us, too. :-) Hard drive space is cheap. Help me fill mine with flight files. Steve Leonard ZS |
#9
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Mangling of U.S. Contest Flight Logs?
On 3/27/2012 9:25 AM, Ron Gleason wrote:
If you want a change made document it and submit it to the rules committee prior to October of each year. The WIINSCORE Users Manual for 2011 can be found here http://www.gfbyars.com/winscore/Winscore%20User's%20Guide.pdf Go to page 40 for the guidelines in the manual for uploading IGC files. Here is a paragraph from that section Minimum time between fixes - Typically, flight data recorders save a fix at 4 second intervals. However, if the .zip file contained every fix that each pilot made for the entire day, the .zip would be too large to send efficiently. Therefore, the scorer can set a new time interval that is used to create the .zip. If the time interval entered here is larger than what the pilot used during his flight, then some of his fixes will be ignored when his flight is put into the .zip. Using a short interval will give more detail to the Internet viewer, but will increase the .zip size and using a longer interval will give less detail to the internet viewer, but will decrease the .zip size. Testing has show that a 15 second interval to be a good tradeoff between resolution and file size. Whining on RAS does not necessarily get things changed, in my experience. Ron I don't think that language requires the scorer to use a longer time interval. The language is "the scorer can set a new time interval". So I don't see why you would go to the rules committee. |
#10
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Mangling of U.S. Contest Flight Logs?
I just installed the 2012 version of WINSCORE.
The defaults I found for Flight Log Transfer a Condense IGC files - OFF If I activated 'Condense IGC Files' then the default value for minimum time between fixes is 4 and the 'Include only the top contestants' value was 15 FWIW Ron Gleason |
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