Number of activities
Since the establishment of SFOR on December 20, 1996, the following monitoring activities were conducted:
|Weapon site inspections||2,294|
| - BiH||783|
| - HVO||679|
| - VRS||832
COMSFOR was General Eric K. Shinseki (US Army). He reported to General Wesley K. Clark, NATO Supreme Commander Allied Forces Europe (SACEUR). SFOR Deputy Commander was General Marc Waymel (French Army). SFOR Chief of Staff was Major General John Drewienkiewicz (UK Army).
Various Component Commanders reported to COMSFOR :
July 24, 1997 (this is the last update)
To support further implementation of the GFAP, and responding to the resolution of the United Nations Security Council (UNSC), the North Atlantic Council (NAC) authorized a NATO-led operation for an 18 month period to deter a resumption of hostilities and to stabilize the peace in Bosnia and Herzegovina (B-H). The operation was designated Operation Joint Guard and was conducted by a Stabilization Force (SFOR).
The Dedicated Off-equipment Work Center (DOW) is composed of two of the original F-16 Avionics Intermediate Shops, plus additional equipment to gain MLU avionics testing capabilities.
The name of the DOW can easily be understood by understanding the term off-equipment: in this work center all F-16 avionics off-equipment maintenance is performed. It is still often referred to as AIS.
Though still part of the Intermediate level maintenance, for the Organizational level the differences between Intermediate and Depot level have faded.
The Dedicated Off-equipment Work center of the Electronic Materiel Depot — operating at Intermediate level — has several tasks, amongst which:
Changes after the F-16 Mid-Life Update
Some of the tasks traditionally performed at Intermediate level (AIS or DOW) will become obsolete once the Mid-Life Update for the F-16 has been completed. The Modular Mission Computer for instance — introduced with the MLU — can be repaired to a certain extend at Organizational level by removal/replacement of printed circuit boards. These removed items are then sent directly to the Depot level for further testing, therefore skipping the Intermediate level.
Another task that has shifted from I to O level is loading and verifying Operational Flight Programs (OFPs) of various Line Replaceable Units. With the MLU the single point OFP loading has been introduced: a single point for loading all software for all avionics subsystems as opposed to removing, loading and re-installing all appropriate avionics Line Replaceable Units separately. In this particular instance the impact on the DOW is low since most LRUs use EEROMs — enabling the loading process to be an integrated part of regular performance testing.
The Dedicated Off-equipment Work center has several test facilities at its disposal:
F-16A/B LRU test equipment (GDE Systems)
F-16A/B MLU LRU test equipment
F-16A/B test stations
When the F-16 entered service the Intermediate level maintenance was performed by the Avionics Intermediate Shop. The first test stations were delivered to the US Air Force in 1978 — the last test stations were delivered by GDE in 1994 (world-wide).
The Radio Frequency (RF) test station is used for testing the various parts of the Fire Control Radar, radio sets, and IFF equipment. The Computer/Inertial (C/I) test station is used for testing the Flight Control System, the Fire Control System, and several other LRUs. The name of this test station is somewhat outdated, since the inertial nav unit is no longer being tested at Intermediate level after the introduction of the newer Ring Laser Gyro unit in the early '90s. The Processor/Pneumatic (P/P) test station is used for testing the air data related LRUs, radar-related LRUs, and Fire Control-related LRUs. The Display/Indicators (D/I) test station is typically used for testing the aircraft's 40 kVA Generator Control Unit, as well as several instruments.
Once the Mid-Life Update has been completed, the workload of these test stations will be reduced drastically.
The D/I test station had a secondary task. With the aid of a set of special test adapters, additional test station hardware and special software this test station was also used in the repair of the printed circuit boards from the F-16A/B test stations. The majority of the cards repaired using these additions were conventional analog circuits that required accurate calibrations and adjustments. Most of the software was developped or rewritten by own personnel.
Improved Avionics Intermediate Shop
MLU specific LRUs as well as most F-16A/B LRUs can be tested using the Improved Avionics Intermediate Shop (IAIS). This modular IAIS test station basically is a combination of all four abovementioned F-16A/B test stations, depending on the configuration. It consists of 14-16 small and two-man portable transit cases which are easier and faster set up when compared to the AIS A/B stations. It was developed by GDE Systems to reduce airlift and personnel and to be independent from available power — it will use anything between 47-440 Hz. The first systems for the US Air Force were delivered in April 1993.
Photo: Based on GDE image.
IAIS test station.
Intermediate-Level Test Set
The Intermediate level Test Set is an advanced test station for the F-16 MLU radar system, in which the Radar Antenna, Radar Transmitter, Signal Data Processor, and modified Low Power Radio Frequency unit can be tested simultaneously as one complete radar system.
Photo: © 1998 A.L.P.
SUREtest 7111 ITS
Testing of Line Replaceable Units
All above mentioned test stations are computer-controlled, running the high order programming language F-16 ATLAS (Abbreviated Test Language for All Systems [Wikipedia]). The ATLAS language has been developed in the 60s by the USAF and several manufacturers. The aim was to create a uniform programming language that would enable manufacturing of uniform test equipment, which was more cost efficient. The F-16 ATLAS version used in the F-16 Avionics Intermediate Shop is a slightly altered version of the original ATLAS language.
For each specific Line Replaceable Unit a dedicated software program is started. It is required to hook up the LRU to the test equipment using a dedicated set of cables and a dedicated hardware interface. Each of the functions of the LRU will be tested in a beforehand determined sequence. The software will assist for a great deal in fault isolation and trouble shooting. Stimulus signals are generated by the test station and measurements and analysis of the measured values are made, indicating a so called Probable Cause Of Failure (PCOF) to the avionics technician in case the measured values are out of specifications. In some cases this may work perfectly fine, in many other cases it comes down to the skills of the technician to isolate the fault. Typically, repair of the LRU can be accomplished by adjusting or removing/replacing Shop Replaceable Units (i.e. Printed Circuit Boards, Power Supplies, etc.) and retesting the failed part of the software.
Shop environment v. aircraft
In theory the test software will always indicate which item in a Line Replaceable Unit is at fault. However, in many cases the fault will not be isolated after the suggested replacement. In other cases, the test software is not able to determine the faulty SRU. In such cases, the test software does not indicate any problem, while the LRU does cause a failure when installed in an aircraft.
Certain aspects contribute to this:
It is also possible that a Line Replaceable Unit has been removed from the aircraft unjustified. There is no way the test software can be able to determine unjustified removals and this will irrevocably cause a clean run on the test station, or result in reported errors that were not the cause of the original failure.
Problems like this require good communications between the technicians at Organizational and Intermediate level, i.e. the shop vs. the flight line. The decision by the Air Force to move the Intermediate level of maintenance away from the Organizational level, and thus hinder communications between the shop environment and the squadron, is therefore a questionable one.