Unlike the U.S.airlines, the U.S. military is still flying and supporting aircraft with avionics systems whose technological heyday is long past. These systems — as well as those of more recent vintage — require constant monitoring to ensure they stay up and running. And, when problems arise, the systems need to be repaired, renewed at the component level, or replaced with more modern technology — all in an environment of budgetary challenge.
Coast Guard Petty Officer 2nd Class Terry Widrlechner,
an avionics electrical technician, performs daily maintenance
on an MH-65 Dolphin helicopter at Air Station Barbers
Keeping the aircraft and their avionics systems going is the job of the flight line maintainers, the intermediate shops, where three-level maintenance is used, and the depots. The hands-on maintainers are supported by supply chain management organizations that work the logistics angles and life cycle management experts, who at least in the U.S. Air Force (USAF), have their own organization, the Life Cycle Management Center (LCMC). As a rule, when it comes to avionics, flight line technicians replace faulty boxes, Intermediate-Level (I-Level) technicians replace boards and depot mechanics—who typically have the most sophisticated equipment — can repair boards and replace chips.
The pros and cons of three-level maintenance have been debated for years, but the current budgetary pressures will increase scrutiny. Hit by rapid-fire budget cuts — and now the sequester military chiefs are looking to save money wherever they can.
Lean and similar efficiency methodologies are a proven way to save money. The 550th Commodities Maintenance Squadron, part of the USAF’s Oklahoma City Air Logistics Complex (ALC), last year was able to increase “turns” for its total avionics inventory or systems being worked on in its shops to 15, meaning that the entire inventory was cycled through 15 times in a year, explains Lee Jones, chief of the 550th’s Avionics and Electronics Flight.
One of the unit’s best results recently has been a reduction in the flow days required to repair a pyrometer, an engine component that measures thermal radiation. With the purchase of a few fairly inexpensive testers, maintainers were able to shorten the repair process from 14 days down to eight days, Jones says.
The Avionics and Electronics Flight also has shown, in the case of certain B-1 components, that consolidation of the maintenance structure can produce savings. In this case the Air Force moved eight high-priority backorder line-replaceable units (LRU) — maintenance cost drivers — from three- to two-level maintenance, Jones explains. This means that any of these items removed on the flight line are sent directly to the depot instead of heading first to the I-Level shops. This move has been a good news story, he says, and has produced significant savings. “I can’t tell you the last time I had a priority back order on any one of those eight items,” he says.
The USAF’s recent “family of testers” initiative, which requires depots to buy automatic test equipment (ATE) from an approved list, could save money, as well, Jones says, because it could allow the three ALCs to maximize their capacity and balance the workload between themselves. Because the ALCs would be using the same testers, a depot with overcapacity could take on some of the overflow work of a depot with a significant backlog.
The depots can go deeper into the electronics than the I-Level shops can, Jones says. The depots, for example, can change chips on boards and repair chassis wiring, whereas I-Level shops swap out circuit cards. This repair expertise also saves money, he says. The Avionics and Electronics Flight, for example, figured out how to repair a group of circuit cards from the C-130 flight control actuator that previously had been considered expendable. As a result of this achievement, the Air Force changed the cards’ designation from expendable to repairable.
Managing the avionics components supply chain is also a complex affair. The 407th Supply Chain Management Squadron (Avionics) and the 408th Supply Chain Management Squadron (Electronic Warfare), for example, oversee management of more than 26,300 avionics and electronic items, supporting more than 750 avionics and electronic warfare systems, according to Bonnie Jones, director of the parent organization, the 638th Supply Chain Management Group.
|Tech. Sgt. John Kerschenheiter, an
electrician with the 191st Maintenance
Squadron, connects wiring for a new
antenna to the flight controls
of a KC-135 Stratotanker at
Selfridge Air National Guard Base, Mich.
One of their success stories is the forward-looking infrared (FLIR) system on the B-52, recalls Kim Herren, director of avionics for the 407th. The B-52 came up on the squadron’s radar because these items were failing and replacement components were not available on the market. These failures, in turn, were leading to aircraft parked on the tarmac, unavailable for their missions. “The B-52 had a big problem,” she says. The squadron, however, was able to have a part designed as a form, fit and function replacement at the item level for the FLIR, which allowed the airplanes to achieve acceptable mission capability (MICAP) levels.
One of the main tasks of the 638th Group is to track maintenance trends in order to identify problem items and work root cause issues to resolve anticipated supportability problems. This process also allows operators and the LCMC to be informed if a system redesign may be more appropriate than at the item-level solution.
The group’s avionics and electronic warfare support work complements that of the LCMC. For one thing, the 407th handles avionics repairs and replacements at the component level, Herren explains. The unit does not undertake major upgrades.
The Life Cycle Management Center handles product support from cradle to grave, says Col. Michael Kelly, chief of the organization’s Electronic Warfare and Avionics Division. The division covers more than 70 electronic warfare systems and more than 500 avionics items. While the unit does not perform actual avionics maintenance, it contracts with industry for support of some aircraft systems and it manages major upgrades.
The division manages contractor logistics support (CLS) agreements with vendors to support the Sniper and LITENING advanced targeting pods with repair and return services. These support contracts are based on estimated use. The operators purchase support by buying groups of pod hours at a fixed price.
The division also is managing the ALQ131A electronic attack pod upgrade project. This takes the legacy ALQ131 shell, incorporates high-power transmission equipment from the ALQ184 combat pod and adds modern digital signal processing equipment. Aimed at the A-10 and F-16 aircraft, “the self-protection jammer will give them more robust protection against surface-to-air and air-to-air missiles and tracking radar as the threat environment moves to digital electronics,” Kelly says. Fielding is slated to begin in late 2014 or early 2015.
The new ALQ131A electronic attack pod also is designed with maintainers in mind. It will have almost 75 percent fewer parts than its predecessors. The Air Force also expects the new pod to more than double the mean time between failure (MTBF), compared to legacy equipment.
With its much smaller infrastructure, the U.S. Coast Guard (USCG) has a different take on avionics repair and overhaul. Unlike the Air Force and the Army, for example, “fixers” are also “flyers.”
At the USCG air station in Clearwater, Fla., Chief Petty Officer Jorge Colonniezes is in charge of the MH-60 Jayhawk avionics shop. He troubleshoots avionics discrepancies to try to isolate problems.
If an MH-60 is ready to ramp up, for example, and experiences a communications problem, the crew calls the shop, “and we go out there and see if we can fix it on the spot,” he says. If not, the flight is cancelled and the aircraft is brought to the shop’s maintenance hangar for further troubleshooting.
The shop uses wiring diagrams, schematics and many years of experience with these aircraft to determine whether there is a wiring problem or a faulty component or box. Most of the wiring-related discrepancies can be fixed in the shop although these issues can be complex and take time to nail down with a handheld multimeter to check voltages, resistance on the lines, opens, shorts and the “usual offenders.”
One issue Colonniezes recalls involved two diodes — one on each engine — that turned out not only to be corroded but also to have been installed backwards. Most of the discrepancies reported by the air crews, however, turnout to be faults in the LRUs.
The Clearwater avionics shop can replace a box but not open it up and work on it. Faulty boxes are shipped back to the USCG’s Aviation Logistics Center, or depot, in Elizabeth City, N.C.
At the Coast Guard ALC Jayhawk avionics maintenance is handled by a staff of two. They work with the air station shops to identify and correct faults and liaison with on-site representatives from the manufacturers “to go outside the troubleshooting manual,” says Chief Petty Officer Pete Van Sicklen, the Jayhawk avionics tech services chief. “It is a 24x7 job,” he says.
Most of the time this process can identify the fault, he says. If the box is under warranty, it’s returned to the manufacturer. There is also a contractor-managed avionics shop on site, which has automatic test equipment and can perform repairs.
Senior Airman Annette Bieniek trains
Airmen on the proper safety wiring in
a central gear box of an F-15E Strike
Eagle at Royal Air Force Lakenheath,
Rockwell Collins supports military customers via performance-based logistics (PBL) contracts and offerings such as FlexForce, says Craig Bries, director of Service Solutions, Americas. The company’s most successful programs have involved “true partnerships” with the military, Bries says.
Under a PBL contract with the Navy, for example, the company supports the head-up displays (HUD) on some 880 F/A-18s. Through understanding the customers’ mission needs, Rockwell Collins was able to “take their mission readiness for that aircraft from below 85 percent to 99 percent,” Bries says. “We work hand in glove with the customer,” he says, providing logistical management, OEM-quality repairs and field service engineering support.
Another Rockwell Collins PBL contract is in support of the Army’s Night Stalkers, the 160th Special Operations Aviation Regiment, a unit that requires 100 percent aircraft and avionics availability for its Little Birds, Chinooks and Black Hawk helicopters, Bries says. The company also supports its avionics systems on some 200 fixed-and rotary-wing aircraft operated by the Coast Guard.