P-3B PROJECT DATA SYSTEM (PDS) CHARACTERISTICS
GTE-PDS (P3-B Only)
The PDS system on board the Wallops P3-B is the primary aircraft data acquisition, display, and distribution system (Figure G1). This system is comprised of two(2) Pentium Pro PCs, instrumentation required for base measurements and interface to aircraft systems, a serial data distribution system, a video distribution system, and a printer (weight and space permitting). The PC's and printer are interconnected via an internal Ethernet network.
The Pentium Pro PCs are used for data acquisition and distribution purposes. The data acquisition PC collects data from various sources on the aircraft. These include the Flight Management System (FMS) and the Inertial Navigation Unit (INU) via a Condor ARINC-429 interface card. Other sources of data provide analog voltage signals which are sampled and collected using a National Instruments data acquisition card. These signals are converted to engineering units and employed to make other flight parameter calculations. Selected PI signals are also recorded through these analog input channels. Time and GPS position data are received through a Bancomm bc627AT card. The PDS time is synchronized to UTC and is available via an IRIG B format signal to PIs as requested.
Alpha-numeric display screens are available via the video distribution system for visual presentation of selected flight parameters and selected PI measurements. The primary alpha-numeric display screen is shown in Figure G2 while other displays will be generated as needed. Graphic presentation of selected parameters using real-time trace plot format (Figure G3) are also
available for mission scientists to assess overall mission status and make in-flight decisions to enhance the successful completion of mission goals. The data distribution system transmits flight data electronically via RS-232 serial data link (refer to section 6.4.2; Serial Distribution System). Serial data parameters are listed in Table G1 and the block format shown in Table G2. PDS analog input parameters and origin are listed in Table G3.
The data stream is divided into 7 blocks of 56 characters each (Table G2). Each of the 7 blocks begins with a letter identifier (C through I) and ends with an ASCII carriage return and a line feed. Parameters within a block are separated by a space and each block is padded with blanks, when necessary, to occupy the full 56 locations. This structure is similar on both aircraft. Blocks H and I are available for augmenting the data field to include additional parameters by the Project Manager as required.
The video distribution system (refer to section 6.4.3) provides PIs different perspectives of the overall mission by providing options to display images from the data distribution PC, forward and nadir camera viewing, or storm scope.
Table G1. P3-B Serial Data Parameters
Output at 19.2K Baud
Variable | Measurement | Format | Units |
---|---|---|---|
EVENT |
Block Number |
aaaaa |
number |
JDAY |
Julian Day |
bbb |
days |
UTMTIM |
UTC Time |
ccccc.cc |
seconds |
FMSALTP |
Pressure Altitude from FMS |
ddddd |
feet |
FMSTAS |
True Air Speed from FMS |
eeee |
knots |
FMSTS |
Static Air Temp. from FMS |
ffff.f |
degs C |
FMSLAT |
Latitude |
gggg.ggg |
degs |
FMSLON |
Longitude |
hhhh.hhh |
degs |
FMSGS |
Ground Speed |
iiii |
knots |
FMSTRG |
Track Angle (True North) |
jjjj.j |
degs |
FMSHD |
Heading from True North |
kkkk.k |
degs |
FMSWNS |
Wind Speed |
llll.l |
knots |
FMSWND |
Wind Direction, True North |
mmmm.m |
degs |
PITCH |
Aircraft Pitch Angle |
nnnn.n |
degs |
ROLL |
Aircraft Roll Angle |
oooo.o |
degs |
DP1011 |
Dew Point |
pppp.p |
degs |
TTDEGC |
Total Temperature |
qqqq.q |
deg C |
J(NO2)Z |
J(NO2) Zenith |
r.rrrrrr |
1/s |
J(NO2)N |
J(NO2) Nadir |
s.ssssss |
1/s |
SURTEMP |
Surface Temperature |
tttt.t |
deg C |
ALTRATE |
Altitude Rate |
uuuuu |
fpm |
PSMB |
Static Pressure |
vvvv.v |
mb |
DIFFMB |
Differential Pressure |
wwww.w |
mb |
TSDEGC |
Static Temperature |
xxxx.x |
deg C |
MACH |
Mach Number |
yyyy.yyy |
none |
TAS |
True Air Speed |
zzzz |
knots |
POTTEMP |
Potential Temperature |
AAAA.A |
degK |
VPSW |
Saturation Vapor Pressure of Water |
BBBB.BBB |
mb |
VPSI |
Saturation Vapor Pressure of Ice |
CCCC.CCC |
mb |
MR |
Mixing Ratio |
DDDD.DDD |
g/kg |
RHW |
Relative Humidity of Water |
EEEE.E |
% |
RHI |
Relative Humidity of Ice |
FFFF.F |
% |
ALTP |
Pressure Altitude |
GGGGG |
feet |
ALTCAB |
Cabin Altitude |
HHHHH |
feet |
RDRALT |
Radar Altitude |
JJJJJ |
feet |
CRYODP |
Cryo Dew/Frost Point |
KKKK.K |
deg C |
CORRRDRALT |
Corrected Radar Altitude |
LLLLL |
feet |
Table G2. Parameter Blocks (56 x 7)
1 | 2 | 3 | 4 | 5 | |||||||||||||||||||||||||||||||||||||||||||||||||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
C | a | a | a | a | a | b | b | b | c | c | c | c | c | . | c | c | d | d | d | d | d | e | e | e | e | f | f | f | f | . | f | g | g | g | g | . | g | g | g | ^ | ^ | ^ | ^ | ^ | ^ | ^ | <cr> | <lf> | |||||||
D | h | h | h | h | . | h | h | h | i | i | i | i | j | j | j | j | . | j | k | k | k | k | . | k | l | l | l | l | . | l | m | m | m | m | . | m | n | n | n | n | . | n | ^ | ^ | ^ | ^ | <cr> | <lf> | |||||||
E | o | o | o | o | . | o | p | p | p | p | . | p | q | q | q | q | . | q | r | . | r | r | r | r | r | r | s | . | s | s | s | s | s | s | t | t | t | t | . | t | u | u | u | u | u | ^ | <cr> | <lf> | |||||||
F | v | v | v | v | . | v | w | w | w | w | . | w | x | x | x | x | . | x | y | y | y | y | . | y | y | y | z | z | z | z | A | A | A | A | . | A | B | B | B | B | . | B | B | B | ^ | ^ | <cr> | <lf> | |||||||
G | C | C | C | C | . | C | C | C | D | D | D | D | . | D | D | D | E | E | E | E | . | E | F | F | F | F | . | F | G | G | G | G | G | H | H | H | H | H | J | J | J | J | J | ^ | ^ | ^ | <cr> | <lf> | |||||||
H | K | K | K | K | . | K | L | L | L | L | L | <cr> | <lf> | ||||||||||||||||||||||||||||||||||||||||||
I | <cr> | <lf> |
Example
1 | 2 | 3 | 4 | 5 | |||||||||||||||||||||||||||||||||||||||||||||||||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 0 | 1 | 2 | 3 | 4 | 5 | 6 |
C | 1 | 0 | 2 | 1 | 1 | 2 | 6 | 7 | 2 | 0 | 0 | 4 | . | 9 | 9 | 2 | 5 | 0 | 7 | 5 | 2 | 9 | 6 | - | 2 | 5 | . | 0 | 3 | 7 | . | 2 | 0 | 4 | <cr> | <lf> | |||||||||||||||||||
D | - | 7 | 2 | . | 0 | 0 | 0 | 2 | 9 | 1 | 0 | . | 0 | 3 | 5 | 6 | . | 5 | 1 | 9 | . | 0 | 2 | 8 | 4 | . | 4 | 1 | . | 5 | <cr> | <lf> | |||||||||||||||||||||||
E | 0 | . | 1 | - | 4 | 6 | . | 7 | - | 1 | 3 | . | 9 | 0 | . | 0 | 0 | 0 | 0 | 0 | 9 | 0 | . | 0 | 0 | 0 | 0 | 0 | 1 | 2 | . | 7 | 1 | 7 | 7 | <cr> | <lf> | ||||||||||||||||||
F | 3 | 7 | 6 | . | 2 | 6 | 7 | . | 7 | - | 2 | 5 | . | 8 | 0 | . | 4 | 9 | 2 | 3 | 0 | 2 | 3 | 2 | 7 | . | 0 | 0 | . | 7 | 5 | 0 | <cr> | <lf> | |||||||||||||||||||||
G | 0 | . | 5 | 8 | 3 | 0 | . | 0 | 9 | 8 | 1 | 2 | . | 4 | 1 | 0 | . | 2 | 2 | 4 | 5 | 3 | 1 | 7 | 8 | 9 | 3 | 2 | 5 | 0 | 0 | <cr> | <lf> | ||||||||||||||||||||||
H | - | 5 | 0 | . | 8 | 2 | 4 | 9 | 9 | <cr> | <lf> | ||||||||||||||||||||||||||||||||||||||||||||
I | <cr> | <lf> |
Table G3. Inputs to PDS P3-B
Source | Signal Type | Parameter | Institution |
---|---|---|---|
Project-Instr. |
Analog |
Dew/Frost Point Cryo Dew/Frost Point UV(Zenith, Nadir) Total Temperature Impact Pressure Pressure Altitude Static Pressure Altitude Rate Surface Temperature |
LaRC |
Project-GPS |
ARINC-429 |
Julian Day UTC Time Latitude Longitude |
LaRC |
Aircraft-FMS |
ARINC-429 |
Pressure Altitude True Air Speed Latitude Longitude Ground Speed Track Angle Heading Wind Speed Wind Direction |
WFF |
Aircraft-INU |
ARINC-429 |
Pitch Roll |
WFF |
Aircraft |
Analog |
Radar Altitude |
LaRC |
(TBD) |
Analog |
CO, CO2, CH4 |
(TBD) |
(TBD) |
Analog |
O3 |
(TBD) |
(TBD) |
Analog |
CN |
(TBD) |
Figure G2: Alpha-numeric displays of selected flight parameters and PI measurements
Figure G3. PDS P3-B Graphical Display Screen