GRIP DC-8 Navigation and Housekeeping Data
Table of Contents
Introduction
The DC-8 is outfitted with a navigational recording system which in combination with REVEAL provides detailed flight parameters such as airspeed, altitude, roll/pitch/yaw angles, ground speed, flight level wind speed, temperature and many others.
The Research Environment for Vehicle-Embedded Analysis on Linux (REVEAL) system is a configurable embedded system for facilitating integration of instrument payloads with vehicle systems and communication links. REVEAL systems currently serve as onboard data acquisition, processing, and recording systems. NASA has Altair-Class REVEAL systems operating on several airborne science platforms, including ER-2, DC-8, WB-57F, P-3B Orion and G-III. This class of full-featured instrument is roughly the size of a loaf of bread and weights 10-20 lbs.
Campaign
The Genesis and Rapid Intensification Processes (GRIP) experiment was a NASA Earth science field experiment conducted August 5 to September 30, 2010. The major goal was to better understand how tropical storms form and develop into major hurricanes. NASA used the DC-8 aircraft, the WB-57 aircraft and the Global Hawk Unmanned Airborne System (UAS), configured with a suite of in situ and remote sensing instruments that were used to observe and characterize the lifecycle of hurricanes. This campaign also capitalized on a number of ground networks and space-based assets, in addition to the instruments deployed on aircraft from Ft. Lauderdale, Florida ( DC-8), Houston, Texas (WB-57), and NASA Dryden Flight Research Center, California (Global Hawk). More information about this Campaign can be found on the GRIP web site :https://ghrc.nsstc.nasa.gov/home/field-campaigns/grip
File Descriptions
The DC-8 REVEAL transfer of housekeeping data allows easy access to aircraft data by experimenter-operated computers. The data were transferred at one second intervals.
Most flights have the four files listed below. There is a mission monitor log (ASCII), which records important flight events, a raw and a quality controlled navigation and housekeeping file (ASCII), which contain detailed aircraft information. There is also a flight track kml file, which when used with Google Earth, shows the complete aircraft flight path.
File Naming Convention
The navigational and housekeeping files are named following the examples below:
GRIP_DC8_ASCII_flightxx_ddMonyyyy-tttt_NAV.txt
GRIP_DC8_CompleteTrack_flightxx.kml
GRIP_DC8_MissionLog_flightxx_ddMonyyyy.log
GRIP_DC8_QC_NAV_flightxx_ddMonyyyy.csv
where:
xx = GRIP flight number (1-15)
dd = day
Mon = month in three characters (Aug, Sep)
yyyy = year
tttt = time in hour, minute
txt = ascii text file
csv = comma-seperated value, contains a comma delimiter (for use in excel)
kml =
Keyhole Markup Language, used for google earth display
log = an ascii type log file
Navigation and Housekeeping Raw ASCII Data
GRIP_DC8_ASCII_flightxx_ddMonyyyy-tttt_NAV.txt
Detailed aircraft information is contained in these serial output (ASCII) files. This format shows seven lines, which are repeated every one second of the flight.
C aaa bb:bb:bb.bb +cc cc.c +ddd dd.d eee.e ffff.f ggg
D hhh iii jjjj kkk.k lll.l mmmmm nnnnn ooooo.o ppppp.p
E qqq.q rrr.r sss.s ttt.t uuu vvvvvv wwwww.w xxxx.x yy
F zzzzz JJJJ.J K.KKK LLLLL.L MMMM.M NNNN.N 000.0 P.PPP
G QQ.Q RR.R SS.S TT.TT UU.UU VVV.V WWW.W XXX.X YYYY.Y
H aaa.a bbb.b ccccc ddddd eeeee fffff ggggg hhhhh
I iii.i jjj.j kkkk.k lllll mmmm.m nnn.n ooo.o ppp.p
These files may be decoded using the following table:
NAV .txt decode table |
Identifier |
Parameters |
Field Format |
Units |
|
|
|
|
C |
Day |
aaa
|
day of year
|
|
Time
|
bb:bb:bb.bbb
|
hour:min:sec (UT)
|
|
Latitude
|
+/-cc cc. c
|
degrees & minutes
|
|
Longitude
|
+/-ddd dd.d
|
degrees & minutes
|
|
Pitch
|
eee.e
|
deg
|
|
Roll
|
ffff.f
|
deg
|
|
Wind speed
|
ggg
|
knots
|
|
|
|
|
D |
Wind direction
|
hhh
|
deg
|
|
True airspeed
|
iii
|
knots
|
|
Ground speed
|
jjjj
|
knots
|
|
True heading
|
kkk.k
|
deg
|
|
Driftangle
|
llll
|
deg
|
|
Pressure altitude
|
mmmmm
|
feet
|
|
Radar altitude
|
nnnnn
|
feet
|
|
Dew/Frost point temperature using GE1011 hygrometer with state flagged
|
ooooo.o
|
deg C
|
|
Dew/Frost point temperature using EG&G hygrometer with state flagged
|
pppp.p
|
deg C
|
|
|
|
|
E |
Static air temperature
|
qqq.q
|
deg C
|
|
Total air temperature
|
rrr.r
|
deg C
|
|
IR surface temperature
|
sss.s
|
deg C
|
|
Static air temperature,
|
|
|
|
calculated
|
ttt.t
|
deg C
|
|
Indicated air speed
|
uuu
|
knots
|
|
Vertical speed
|
vvvvvv
|
ft/min
|
|
Distance to go
|
wwwww.w
|
nm
|
|
Time to go
|
xxxx.x
|
min
|
|
Align status
|
yy
|
|
|
|
|
|
F |
Cabin altitude
|
zzzzz
|
feet
|
|
Pressure
|
JJJJ.J
|
mb
|
|
Mach number
|
K.KKK
|
|
|
Cross track distance
|
LLLLL.L
|
nm
|
|
Desired track
|
MMMM.M
|
deg
|
|
Track angle error
|
NNNN.N
|
deg
|
|
Track angle
|
OOO.O
|
deg
|
|
Specific humidity
|
P.PPP
|
g H20/kg air
|
|
|
|
|
G |
Partial pressure H20
|
QQ.Q
|
mb
|
|
Relative humidity with respect to ice
|
RR.R
|
%
|
|
Relative humidity with respect to water
|
SS.S
|
%
|
|
Saturation vapor pressure of water
|
TT.TT
|
mb
|
|
Saturation vapor pressure of water relative to ice
|
UU.UU
|
mb
|
|
Sun elevation in ground reference frame, refracted
|
VVV.V
|
deg
|
|
Sun elevation in aircraft reference frame, refracted
|
WWW.W |
deg
|
|
Sun azimuth in ground reference frame
|
XXX.X
|
deg
|
|
Sun azimuth in aircraft reference freme relative to the nose of the aircraft
|
YYYY.Y
|
deg
|
|
|
|
|
H |
egi True Heading |
aaa.a |
0-360 degrees |
|
egi magnetic heading |
bbb.b |
0-360 degrees |
|
egi x velocity |
ccccc |
+/- 9000 |
|
egi y velocity |
ddddd |
+/- 9000 |
|
egi z velocity |
eeeee |
+/- 9000 |
|
egi x acceleration |
fffff |
+/- 1100 |
|
egi y acceleration |
ggggg |
+/- 1100 |
|
egi z acceleration |
hhhhh |
+/- 1100 |
|
|
|
|
I |
Air Data Computer Total Air Temp |
iii.i |
-99.0 to 50.0 |
|
Rosemont Total Air Temp |
jjj.j |
-99.0 to 50.0 |
|
Potential Temperature |
kkk.k |
-999.0 to 1000.0 |
|
GPS Altitude MSL |
lllll |
-2000 - 70000 |
|
S Camex Dew/Frost point |
mmmm.m |
-100.0 to 70.0 |
|
Sun Elevation Angle wrt Earth |
nnn.n |
-90.0 to 90.0 |
|
Sun Elevation Angle wrt Aircraft |
ooo.o |
-90.0 to 90.0 |
|
Sun Azimuth Angle wrt Earth |
ppp.p |
0 - 360 |
All data parameters are in engineering units. For integer formats, the number of digits in a field may vary from one to the number shown in the field format. For non-integer formats, the placement of the decimal point within the field and the number of digits to the right of the decimal point are guaranteed as illustrated in the field format. However, the number of digits to the left of the decimal point may vary from one to the number shown in the field format. Unused leading digits are padded with either blanks or zeroes. Units are not included in the data stream.
Individual parameter fields will be filled with special characters for the following reasons:
Condition
Data was too big for parameter field
Data was too small for parameter field
Data formatting error occurred |
Special Character
>
<
? |
Additionally, invalid or unavailable data may be replaced by question marks (?), however, the absence of question marks in a parameter field does not guarantee the validity of the data.
Navigation and Housekeeping Quality Controlled Data Files
GRIP_DC8_QC_NAV_flightxx_ddMonyyyy.csv
These NAV data files have been quality controlled and are in comma-seperated value format (ascii). The data are displayed in columns with labels in the following order:
UTC
Latitude
Longitude
GPS_Altitude
Pressure_Altitude
Radar_Altitude
Ground_Speed
True_Air_Speed
Indicated_Air_Speed
Mach_Number
Vertical_Speed
True_Heading
Track_Angle
Drift_Angle
Pitch_Angle
Roll_Angle
Static_Air_Temp
Dew_Point
Dew_Point-3_Stage
TAT_Aircraft
TAT_Experimenter
IR_Surf_Temp
Static_Pressure
Cabin_Pressure
Wind_Speed
Wind_Direction
Solar_Zenith_Angle
Aircraft_Sun_Elevation
Sun_Azimuth
Aircraft_Sun_Azimuth
Mixing_Ratio
Part_Pressure_H2O
Part_Pressure_Ice
H2O_Sat_VP_Water
H2O_Sat_VP_Ice
Rel_Humidity_H2O
Rel_Humidity_Ice
Mission Manager Log
GRIP_DC8_MissionLog_flightxx_ddMonyyyy.log
These are plain text messages which record important events during the flight. They are the managers time stamped commentary of observations during the flight, annotating them with time, position, altitude, and other information.
Graphic Representation
GRIP_DC8_CompleteTrack_flightxx.kml
In addition to the text version of flight data, a kml file has been included to display flight paths during the course of the flight using Google Earth.
Contact Information
The data producer is:
David Van Gilst
DC-8 Network Engineer
National Suborbital Education and Research Center
University of North Dakota
To order these data or for further information, please contact:
Global Hydrology Resource Center
User Services
320 Sparkman Drive
Huntsville, AL 35805
Phone: 256-961-7932
E-mail: support-ghrc@earthdata.nasa.gov
Web: http://ghrc.nsstc.nasa.gov/
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