APPENDIX G

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

[Alpha-numeric displays of selected flight
      parameters and PI measurements]

 

 

Figure G3. PDS P3-B Graphical Display Screen

[PDS P3-B Graphical Display Screen]