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snip / flightLGo

OGN automate flightlog written in Golang & PHP
GNU General Public License v3.0
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Landing event generated from erroneous APRS data #6

Open Ventusfahrer opened 4 years ago

Ventusfahrer commented 4 years ago

The first Landing event from

https://flightlog.glidernet.org/?airfield=Bensheim&d=2020-09-06&tf=HMUTC&devID=1

has not taken place.

By chance I was running a modified version of the flightLGo software to trace APRS data in order to run my own flightlog web server. Attached you will find the data collected.

FLRDD9FBD>APRS,qAS,Bensheim:/073655h4941.41N/00835.06E'169/053/A=000482 !W23! id06DD9FBD -7404fpm +0.0rot 36.0dB 0e +1.2kHz gps28x37
FLRDD9FBD>APRS,qAS,Bensheim:/073656h4941.39N/00835.06E'170/039/A=000361 !W77! id06DD9FBD -5543fpm +0.0rot 35.0dB 0e +1.2kHz gps22x30
FLRDD9FBD>APRS,qAS,Bensheim:/073657h4941.38N/00835.07E'170/031/A=000292 !W80! id06DD9FBD -4395fpm +0.0rot 37.2dB 0e +4.6kHz gps20x28
FLRDD9FBD>APRS,qAS,Bensheim:/073658h4941.38N/00835.07E'168/025/A=000253 !W31! id06DD9FBD -3583fpm +0.0rot 37.8dB 0e +1.2kHz gps19x27
FLRDD9FBD>APRS,qAS,Bensheim:/073659h4941.39N/00835.06E'000/000/A=000351 !W57! id06DD9FBD -058fpm +0.0rot 37.5dB 0e +1.2kHz gps16x22
FLRDD9FBD>APRS,qAS,Bensheim:/073700h4941.39N/00835.06E'180/000/A=000338 !W38! id06DD9FBD -058fpm +0.0rot 35.8dB 0e +1.2kHz gps15x21
FLRDD9FBD>APRS,qAS,Bensheim:/073701h4941.39N/00835.06E'000/000/A=000318 !W28! id06DD9FBD -098fpm +0.0rot 34.0dB 0e +1.2kHz gps4x6
FLRDD9FBD>APRS,qAS,Bensheim:/073716h4941.39N/00835.06E'000/000/A=000312 !W38! id06DD9FBD +020fpm +0.0rot 33.0dB 0e +1.2kHz gps3x4
FLRDD9FBD>APRS,qAS,Bensheim:/073736h4941.39N/00835.06E'000/000/A=000315 !W28! id06DD9FBD +020fpm +0.0rot 36.5dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073756h4941.39N/00835.06E'000/000/A=000315 !W28! id06DD9FBD +020fpm +0.0rot 33.0dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073816h4941.39N/00835.06E'000/000/A=000318 !W28! id06DD9FBD +020fpm +0.0rot 33.0dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073836h4941.39N/00835.06E'000/000/A=000321 !W38! id06DD9FBD +020fpm +0.0rot 30.0dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073849h4941.39N/00835.06E'000/000/A=000315 !W48! id06DD9FBD +020fpm +0.0rot 30.5dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073909h4941.39N/00835.06E'000/000/A=000312 !W38! id06DD9FBD +020fpm +0.0rot 31.0dB 0e +1.1kHz gps3x5
FLRDD9FBD>APRS,qAS,Bensheim:/073929h4941.39N/00835.06E'000/000/A=000315 !W38! id06DD9FBD +020fpm +0.0rot 29.2dB 0e +1.1kHz gps3x4
FLRDD9FBD>APRS,qAS,Bensheim:/073949h4941.39N/00835.06E'000/000/A=000315 !W29! id06DD9FBD +020fpm +0.0rot 28.0dB 0e +1.1kHz gps3x4
FLRDD9FBD>APRS,qAS,Bensheim:/074009h4941.39N/00835.06E'000/000/A=000318 !W39! id06DD9FBD +020fpm +0.0rot 29.8dB 0e +1.1kHz gps3x4
FLRDD9FBD>APRS,qAS,Bensheim:/074029h4941.39N/00835.06E'000/000/A=000321 !W39! id06DD9FBD +020fpm +0.0rot 28.8dB 0e +1.1kHz gps3x4

It points out, that the first 4 logs of Flarmdevice DD9FBD are reporting likely erroneous high sink rates ( > 4000 fpm), whereas the difference in altitude is much less than the sink rate. Maybe this happens during initializing the pressure sensor of the Flarm??

Anyway, the first landing in the flightlog was not happening at all.

gnu zipped data file is attached.

greets

Peter

PS: thank you for the very good algorythm calculating takeoff and landing events. flightlog.glidernet.org is much more reliant than logbook.glidernet.org!!

20200906.APRS.dat.gz

snip commented 4 years ago

With a quick look we can see that the GPS initialisation is reporting wrong speed before 07:36:59. The algorithm looks only at speed. So it was thinking that DD9FBD/D-4608 was flying. So i think we need to check the GPS precision (ie gps28x37) and ignore when not precise enough.