Wanted! Specification of .igc file-format
cirrus
Michael Deleo
Does anyone have specifications for the .igc file-format?
-- ______________________________________________________ Michael Deleo - Market Development Engineering Sun Microsystems Computer Company Tel: 650 786-4084 Fax: 650 786-9555 Email: michae...@eng.sun.com
Dave Ellis
>
> Does anyone have specifications for the .igc file-format?
I was unable to find the original document at the FAI site:
http://www.fai.org/gliding
Here is a brief description of Cambridge .IGC files:
===============Flight Log File Description =========================
ACAM00043 "A record - CAMbridge + 4 digit Serial number"
HFDTE050696 "UTC Date 5 June 1996"
HFFXA050 "This is the "Fix Accuracy" Statement"
HFSITSite: Rayskala "PC database site name"
HFTZOTimezone: 3 "Local time offset from UTC"
HFDTM100Datum: WGS-84
HFPLTPilot: Uli Schwenk
HFGIDGlider ID: KS
HFCCLCompetition Class: OP
HFUNTUnits: km,k/h,m,m/s
I033638FXA3941ENL4247REX
"The I record describes B record extensions"
LCAMN00001 60 44.549N 024 07.080E 00121.0 TAH Rayskala
LCAMN000026045130N02354580E001500T Porras
"L Records are turnpoints in the GPS-NAV database"
B1336576104081N02309954EA0017800129045025060001
"A typical flight has more than 2000 B records"
B1337256104316N02309846EA0011000126060048075001
B1337296104325N02309763EA0011000091045094060003
"B Records are for each fix, see below"
G8E9FD407ECB7FFE37FBA3522A9965B7EC5264A0345B5F13B28B2965B17B2C276CFA9
"G records are the security signature for the IGC flight file"
============ Guide to Interpretation ==============================
0 1 2 3 4
1 234567 89012345 678901234 5 67890 12345 678 901 234567
B HHMMSS DDMMMMMN DDDMMMMME A PPPPP GGGGG FXA ENL REX
B 133729 6104325N 02309763E A 00110 00091 045 094 060003
Description Size Element Remarks
Time UTC 6 bytes HHMMSS Valid characters 0-9
Latitude 8 bytes DDMMMMMN Valid characters N, S, 0-9
Longitude 9 bytes DDDMMMMME Valid characters E,W, 0-9
Fix valid 1 byte V A: valid, V: nav warning
Press Alt, Meters 5 bytes PPPPP Valid characters -, 0-9
GNSS Alt, Meters 5 bytes GGGGG Valid characters -, 0-9
Pressure Altitude is referenced to 1013.2 mBar
I NN SS FF MMM SS FF MMM SS FF MMM
I 03 36 38 FXA 39 41 ENL 42 47 REX
(This is the the Cambridge "I" record extension for the "B" record)
Description Size Element Remarks
# of extensions 2 bytes NN Valid characters 0-9
Start byte number 2 bytes SS Valid characters 0-9
Finish byte number 2 bytes FF Valid characters 0-9
3-letter Code 3 bytes MMM Valid characters alphanumeric
Bytes 36-38 are FXA, horizontal fix accuracy in Meters (0 is 2D fix)
Bytes 39-41 are ENL, engine noise level (000 - 196)
Note: GPS-NAV ENL display is .IGC file number multiplied by 21/8
Bytes 42-47 are REX, reserved for Cambridge use
Bytes 42-44 are Vertical EPS (fix accuracy) in Meters.
Bytes 45-47 are the decimal representation (0-255) of a Status byte
(Bit 0 On-task, Bit 1 Engine-On, Bit 4 GPS Recorder software error,
Bit 5 Dead Reckoning, Bit 6 NAV recvr warning, Bit 7 Invalid GPS data)
============= End of Document =======================
Regards,
Dave Ellis
Cambridge Aero Instruments
cdeerinck
> cirrus wrote:
> >
> > Does anyone have specifications for the .igc file-format?
> I was unable to find the original document at the FAI site:
> http://www.fai.org/gliding
So for those that come looking behind me, here is the answer:
The official FAI IGC File format document as of 2022 can be found here:
https://www.fai.org/sites/default/files/igc_fr_specification_2022_with_al7_2022-1-31.pdf
New versions (if/when they become available), should be here:
https://www.fai.org/igc-documents
then go to Flight Recorders, and then under IGC-approved Flight Recorders - Technical Specification