BARCS & SACS

T-38 Flight Recorders

The T-38 flight recorder was developed to support air force training requirements in the T-38 aircraft.  It supports the collection of video data from our HUD camera or any RS-170 video source.  Data is recorded on standard 8 mm video tapes.  The system is designed and tested for daily airborne operation with minimal maintenance.  The design has been refined and verified based on the successful deployment of over 100 systems during the past 10 years.

NASA Schlieren and Grimace Computers

PVPAEO has developed a range of digital flight qualified airborne recorders and computers.  These systems utilize the latest developments in commercial technology coupled with proven mounting and packaging methods to meet challenging airborne, marine and ground based environmental requirements.  These systems have been used for recording digital data form IR and visible sensors, navigation, and moving map displays.

PVPAEO is currently in the final stages of developing an IR imaging system with NASA-Dryden to support flow visualization studies using IR thermography. A 3-5 micron staring sensor is currently deployed in an externally mounted podlet located on the F-15 aircraft as shown. It has a fixed line of sight centered on the region of interest. Based on initial in-flight data collection efforts, this approach appears to provide consistent high quality data for a wide range of flight conditions.

IR Podlet installed on the right side of the F-15 aircraft.

The imaging system is based on a Raytheon Radiance HS camera.  The camera utilizes an InSb focal plane with 256x256 30 micron pixels.  A 13mm lens was selected to capture a complete view of the experiment with minimal background within the field of view.

To minimize the size of the podlet and resultant drag, the sensor is oriented parallel to the air flow.  This also places the line of sight parallel to the experiment.  A fold mirror is incorporated in the design to fold the line of sight inboard and down to center on the region of interest (see below).  A silicon window with an antireflection coating optimized for the 3-5 micron spectral band is installed on the inner surface of the podlet directly in front of the fold mirror.

To further minimize the volume of the podlet, the camera electronics are installed in an adjacent aircraft bay with an interface cable connection to the camera head.  The electronics package provides simultaneous NTSC, Y/C and 12 bit digital output.  The camera operational settings can be adjusted through an RS-422 computer interface.  The system is equipped with test ports and cables to enable external configuration and test support without the need for aircraft power.

Data is currently collected on HI-8 videotape using the Y/C output from the camera.  This data is digitized after collection for further analysis.  To further optimize the quality of the data PVPAEO is currently implementing an airborne digital recording system to record data from the 12 bit digital output.  The recording system will support continuous collection of 12 bit digital data for up to two hours.  Data collection can be started and stopped using a cockpit control switch.  Flight data is downloaded to a portable FireWire hard drive at approximately three times the real time recording rate.  The portable drive can be connected to a computer workstation or network for long term storage or analysis.