Larsen & Brusgaard VISO, Руководство пользователя

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Example: A skydiver (in a fixed freefall position) who has a terminal fall rate of
62 meters/sec at 10,000 feet will have a terminal fall rate of 50 meters/sec at
3,000 feet.
It will be seen that the difference in altitude (air pressure) makes it difficult to
compare the fall-rates when measured using TAS.
SAS. The SAS formula calculates airspeed (using the same metrics used with TAS) as
though the complete skydive had been performed at a fixed air pressure and a fixed
temperature which corresponds to 4,000 feet ASL. 4,000 feet is chosen as the refer-
ence altitude by LARSEN & BRUSGAARD since this is the average altitude at which
the working time of a skydive is normally ended.
Conclusion
Using SAS , skydivers in any body position can express their vertical speed by a
number ( SAS ). This number remains virtually constant regardless of altitude with
APPENDIX
TAS and SAS
Definitions
True Airspeed (TAS)
and Skydiver’s Airspeed (SAS) are two methods of calculating
the airspeed of a moving/flying/falling object.
TAS is a term used in aviation: It is the speed of an object relative to the surround-
ing air, regardless of the altitude.
SAS is a new concept developed by LARSEN & BRUSGAARD:
SAS is the speed of a
skydiver calculated from measurements of air pressure and
temperature and converted to a fixed air pressure (875.3 mb) and a fixed tempera-
ture (+7.080C) which corresponds to 4,000 feet ASL.
TAS . A skydiver’s True Airspeed (TAS) relative to the ground changes as a function
of the altitude (air pressure) and temperature which makes it difficult to compare
fall-rates.
APPENDIX