1. NCAR Aviation Facility ADS II Overview Chris Webster, National Center for Atmospheric Research

2. Overall Theme 1) Data Acquisition - ADS (Aircraft Data System) - DSM (Data Sampling Module) 2) Data Recording - discWin - Raw Data / ADS file - Removable disk 3) Data Processing - nimbus processor 4) Display - WINDS (current program) - aeros (new program)

4. Each box can sample: 64 Analog channels up to 10K samples per second (sps) 64 bits of Digital and/or counter 8 Serial ports, RS-232 and RS-422 3 PMS-1D probes 2 PMS-2D probes ARINC 429 Synchro VME Chasis 12 card cage Modular power supply vxWorks RTOS

5. Network topology display-netdata-net DSM Display TimeServer IRIG & NTP DataServer Linux PC self-recording instrument Iridium DSM

6. System Architecture; Data Flow Raw Data (ADS file) Processor (nimbus) Onboard Data Server Display (WINDS) Serial Feed Data Logger (discWin) DSM Data Acquisition and RecordingData Processing and Display Display (WINDS) Transmit to ground via iridium Inputs - Analog - Digital - Serial Shared Memory User instruments Data-net Display-net

7. Current System Architecture Raw Data Processor On The Ground netCDF file Display & Analysis De-spike De-spike Time Shift Time Shift FIR filtering (HRT) FIR filtering (HRT) Derived parameters Derived parameters Real-time Real-time Web-based Web-based Post-flight Post-flight

9. System Specifications OS: Redhat Linux 9.0 and later. OS: Redhat Linux 9.0 and later. Language: All of our code is C and/or C++. Language: All of our code is C and/or C++. GUI: Motif, tied to Unix. New developments in Qt (KDE), which is portable to MS-Win, Mac, Unix. GUI: Motif, tied to Unix. New developments in Qt (KDE), which is portable to MS-Win, Mac, Unix. Typical flight is 8-9 hours with 300-375 variables Typical flight is 8-9 hours with 300-375 variables 60-80 Analog channels. 60-80 Analog channels. 120-130 raw block data (PMS, GPS, IRS, etc). 120-130 raw block data (PMS, GPS, IRS, etc). 120-160 derived variables. 120-160 derived variables.

10. Processor Features Low Rate (1hz), High Rate (25hz), Sample Rate, Real- Time. Low Rate (1hz), High Rate (25hz), Sample Rate, Real- Time. De-spike; remove spikes up to 1 second in duration. De-spike; remove spikes up to 1 second in duration. Time shift up to plus or minus 1 second. Time shift up to plus or minus 1 second. FIR rate-change filter (HRT processing). FIR rate-change filter (HRT processing). Mask out of bad data. Mask out of bad data. Quality/Error checking (in development) Quality/Error checking (in development) Spike detection Spike detection Flat line detection Flat line detection Out of bounds/range detection Out of bounds/range detection

11. Output file – netCDF Hardware architecture independent. Hardware architecture independent. Self describing (meta-data). Self describing (meta-data). Supports multi-rate data (e.g. ATX @ 25hz, LAT @ 5hz, PMS @ 10hz, etc). Supports multi-rate data (e.g. ATX @ 25hz, LAT @ 5hz, PMS @ 10hz, etc). Fortran, C, C++, and Java language API’s. Fortran, C, C++, and Java language API’s. Interfaces: Matlab, IDL, Python, Perl & Tcl/Tk. Interfaces: Matlab, IDL, Python, Perl & Tcl/Tk. OpenDAP allows network reads via http. OpenDAP allows network reads via http. http://www.unidata.ucar.edu/packages/netcdf http://www.unidata.ucar.edu/packages/netcdf http://www.unidata.ucar.edu/packages/netcdf NCAR “Conventions” for aircraft data registered with Unidata. NCAR “Conventions” for aircraft data registered with Unidata. Used by NCAR, University of Wyoming and NOAA. Used by NCAR, University of Wyoming and NOAA.

12. NCAR netCDF multi-rate record layout 1hz 5hz 1hz1hz, vector 161hz 25hz 10hz vector 16 Dimension 1 is the record dimension, 1 record per second Dimension 2 Sub samples 1hz Dimension 3 Vector Data (PMS1D)