Embedded Files
North American Aviation proposed a true systems solution to the tactical reconnaissance mission. This approach was named, "Integrated Operational Intelligence System." It was composed of two major components: the RA-5C aircraft and its supporting infrastructure, and a dedicated facility on large deck carriers, called "Integrated Operational Intelligence Center" or IOIC.
IOIC, located on the 03 level roughly amidships on Forrestal and subsequent classes, was the principal space for air wing planning, briefing and debriefing. Most wing Air Intelligence functions were carried out here as well. AI staff, though generally formally assigned at the squadron level, had their work spaces and offices here as well. Cyclic operations were briefed to ready rooms though closed circuit TV. Major air wing wide operations, such as alpha strikes, were held in IOIC spaces.
The part of IOIC that directly supported the IOI "System" was primarily located in the "multi sensor interpretation area", highlighted in the diagram nearby. This contained a number of 'Multispectral Interpretation Viewers," also shown nearby. These devices were used to view and analyze sensor imagery, primarily photographic film. The viewer automatically displayed ground position, and allowed the photo interpreter to perform all required photointerpretation tasks in a semi-automatic manner. For example, selected imagery segment could be viewed at high magnification. Image mensuration could be carried out automatically as well.
The "multispectral" portion of the nomenclature is derived from the ability of the equipment to process data from multiple sensor modalities employed by the RA-5C: framing and panoramic cameras, Ku band real beam side looking radar, as well as signals intelligence collection.
The system worked well, in theory at least. The automatic processes were helpful mainly in processing film for new operational areas, where determination of ground features was paramount. Since during the 1967 Westpac cruise the air wing was operating over essentially the same geographic area for weeks and months at time, this ability to quickly analyze new terrain was less advantageous. There was a labor overhead in loading the film into the viewer that mitigated against its use in most cases.
There was another issue with the use of the viewers. One problem facing the system designer was how to embed metadata from the flight into the imagery. On other aircraft, this was done by including a clock in the corner of the film frame. This was inadequate for the planned use of the viewer, which required virtually all flight data: position, altitude, airspeed, attitude in three axis, ground speed, etc. This information was available in digital form internally to the RA-5C. How to transfer to Viewer?
The solution?
A combination of ingenuity and simplicity. The film was still to be used for the data transport medium. Instead of an analog image of a chronometer, the complex data collected by the RA-5C's AN/ASB-12 nav system was embedded "digitally" on the film. The RA-5C film format is shown nearby on the right for a panoramic camera, in the the KA-58 18" pan. A small area between frames is used to store the data. Information stored on the "code matrix block" includes:
Date
Time
Unit
Sensor ID
Sensor mode
Barometric altitude
Heading
Drift
Roll
Pitch
ASB-12 mode
Radar Altitude
Longitude
Latitude
ESM data (for Passive Electronic Countermeasure set only)
See template nearby for actual data format.
Instrumentation in the IOIC itself is used to read the code matrix block and display it to the photo interpreter. The concept, while a good one in principle, didn't work so well in a tactical environment. Mounting film reels in the large PI consoles was not a trivial task (see photo above of the Multisensor Interpretation Viewer in action). Plus, PI's become very familiar with terrain features during the course of a combat cruise so the geoposition data and the like was not generally needed. Also, for the system to work properly, all components in the system had to be in good working order for the overall process to work. Take navigation for example:
the ASB-12 needed to generate accurate nav and attitude data
The nav data needed to be transferred to the sensor without error
these data needed to be accurately imaged on the moving film
The viewer needed to properly read the code matrix block
The data needed to be properly displayed.
Needless to say, this requires a lot of work to optimize all the elements involved in this process. Most of the time on Yankee Station in 1967 it just wasn't worth the effort.
An exception was the ALQ-61 passive ECM collection system which stored its data digitally on computer compatible magnetic tape, which included a representation of the code matrix block. This is one part of the systems that was used often and was impressive in action. The tape was unloaded from the aircraft and mounted on the reader/processor in IOIC. Reading and processing the tape was, to the untutored eye, a more less automated processes which produced a map of emitters across North Vietnam very quickly once a tape was mounted.
IOIC was the focal point of collection and compilation of tactical reconnaissance infromation. This information was processed and reviewed by Air Intelligence Officers for use of their various squadrons (note: AI's were assigned to squadrons but spent most of their time in IOIC or other intelligence spaces.)
We RA-5C crews generally planned our own missions, independent of the air wing. We did this in dedicated squadron spaces known as "the Vault." I spent a lot of time here trying to get up to speed on threat data, order of battle, and other important information.
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