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UPS Air: Data Analytics for 5 Billion Packages

UPS ensures aircraft maintenance delays do not impact its ability to delivery every package to its destination on time by using an extensive fleet data analytics program that takes advantage of line-fit avionics and Boeing’s airplane health management (AHM) system, among other digital analytics tools.

UPS delivered 5.1 billion packages via air and ground in 2017. The Kentucky-based global logistics company also increased flight frequencies in the Asia-Pacific region last year, while adding a five-time-per-week flight between Louisville and Dubai, its longest route at 6,691 nm. The air cargo carrier is also now operating new routes in Lithuania, Poland and Spain, and a new chartered flight between its European hub in Cologne, Germany, and Casablanca.

UPS ensures aircraft maintenance delays do not impact its ability to delivery every package to its destination on time by using an extensive fleet data analytics program that takes advantage of line-fit avionics and Boeing’s airplane health management (AHM) system, among other digital analytics tools.

“We’re flying a lot of flight critical stuff, like medical supplies that have to be delivered within a 24-hour period,” said Tom Wagner, manager of aircraft maintenance technical support and data analytics at UPS. “Having data ahead of time, and being able to get to aircraft maintenance gateways and have them understand the problem and diagnose it as quick as possible, is critical to our mission. The data allows us to do that.”

UPS’ fleet is made up of 240 aircraft, the majority of which are Boeing 757s and 767s, Airbus A300s and McDonnell Douglas MD-11s. Between 2019 and 2022, UPS will add 14 new 747-8 freighters and four new 767s.

The Pain Index

Over the past decade, the maintenance division of UPS Air Cargo has been using a combination of digital analytics tools for its fleet maintenance program. What it has established is what Wagner refers to as a “pain index.” By constantly monitoring pilot reports and service failures associated with specific aircraft types within its fleet, it has identified specific aircraft systems and components that cause the most pain. Based on the operational thresholds established for those systems, UPS receives fault-code messaging and triggered alerts, alerting it to when a system or component is on the brink of failure.

“That pain index is a compilation of delays, cancellations, pilot reports and minimum equipment list (MEL) items,” said Wagner.

The maintenance team has documented the causes of service failures using the Air Transportation Association (ATA) aircraft component and numbering system.

UPS ensures aircraft maintenance delays do not impact its ability to delivery every package to its destination on time by using a fleet data analytics program.Photo courtesy of UPS

“For example, ATA-36 is pneumatics, ATA-21 is air conditioning and ATA-29 is hydraulic power. Those cause the greatest deal of pain,” Wagner said. “We develop triggers for them to where we can impact that pain index number and bring it down by getting to maintenance ahead of time before it manifests itself in a delay, cancellation or service failure.”

According to Wagner, UPS uses a data-driven approach to monitoring the pneumatic pressures on its Boeing 767s and 747s. On every 747 and 767 takeoff, his team takes a look at the pressure of the pneumatic system at 80 kt from takeoff. If the pneumatic system’s pressure level exceeds the established pressure threshold, then the team understands that one of the components within the pneumatic system is on the brink of failure. Once the pressure exceeds the threshold, a work order is written so that the identified part causing the pressure problem is swapped out before it fails. This is best known as predictive or proactive aircraft maintenance.

“Pneumatic system pressurization problems can cause rejected takeoffs on the 747 and 767,” said Wagner. Additionally, if a pressurization system or pneumatic system is removed temporarily, airborne UPS aircraft can suffer from penalties. A penalty they could incur is not being able to land on a wet runway, because aircraft flying without a thrust reverser cannot land on wet runways. Thus, the team members try to ensure that maintenance is performed in a timely manner so that they almost never have to take off with a missing thrust reverser.

MD-11 Analytics

The MD-11 has been flying for more than 25 years with UPS, and there are no plans on retiring the airframe. In an effort to keep all MD-11s flying as efficiently as possible, UPS has developed a fleet-specific data analytics program applicable to all 37 of the MD-11 freighters it operates.

From a telemetry standpoint, the MD-11 analytics fleet health strategy has expanded in recent years to capture all of the pneumatic temperatures coming off the engines in three different stages, according to Randy Miller, who leads the MD-11 data analytics program for UPS.

Miller said that the MD-11 telemetry strategy focuses on capturing pneumatic temperatures produced by the aircraft engines in three stages. The first stage is a reading of the direct engine temperature, followed by an intermediate stage and a final manifold stage. By monitoring the intermediate temperature of the air coming off the engine, UPS is able to determine the health of the valves that provide the pneumatic pressure and temperature, and remove them before they fail in flight.

Between 2019 and 2022, UPS will add 14 new 747-8 freighters.Photo courtesy of UPS

“From this capturing of information over a period of time, we have learned that we can predict impending failure of what’s known as the high-stage valve,” said Miller. “That captures the highest amount of air pressure that comes off the engine, and that’s where we supplement during cruise for pneumatics and for the air conditioning system.”

Miller said the strategy is also used for anti-icing of the aircraft. “Having a precursor to an impending failure of the valves saves us a considerable amount of time when maintenance needs to be done,” he added.

By analyzing pilot reports over time, UPS also started heavily monitoring the margin between the aircraft pitch limit and aircraft pitch indicators. As the margin between the two indicators is reduced, it is an indication that the aircraft is moving closer to encountering a stall condition.

“We actually capture this information of what the aircraft pitch is versus the pitch limit and calculate the margin, and we can then make an adjustment to the aircraft,” said Miller. In the case of one of its airplanes, the team found it had been built incorrectly and needed an adjustment to the angle of attack sensor, Miller said. “This is the kind of information we couldn’t capture in the past, but we’re doing it now and getting smarter about capturing information on older, more legacy-style aircraft that typically didn’t provide this information in the past.”

Every MD-11 departure is required to go through a hydraulic pump test during the pre-flight check of the aircraft. A hydraulic system controller on the airplane monitors the functions of the hydraulic system. If there is a problem with the engine-driven pump, the test only tells you about the failure on departure, when the engine started.

“We’re working on trying to get a better handle on knowledge of that, but right now we honor all of the hydraulic pump fail messages,” said Miller. By capturing data about what’s occurring, Miller can advise the maintenance staff on what pump is causing a problem.

Using Boeing’s AHM on the MD-11, UPS is also looking at the integrated drive generators on board the aircraft and watching the generators and other elements on a servicing chart for any action that needs to be taken.

A Proactive Maintenance Future

There are still several aspects of UPS’ fleet data analytics program that it is modernizing.

An ongoing upgrade is a refresh of the cockpit avionics and embedded computing architecture of its Airbus A300s, which it first received in 2001. Across the entire A300 fleet, installations of new flight management computers, central maintenance systems and better processing power upgrades are occurring, which will allow for faster updates to those aircraft navigation databases. UPS is installing Honeywell servers on board, said Wagner.

“The reason we’re doing that is our FMS has capped out on the amount of memory it has for the nav databases, so we need bigger memory databases,” he said. “We use tablets via Wi-Fi to communicate with servers and upload the navigation databases. Instead of connecting to just one FMC at a time, we’re uploading both computers simultaneously.”

Wagner said this method cuts down on turn time. “Normally what would take 45 minutes, now it will take about 15 to 20 minutes to get them all uploaded,” he said.

Other newer analytics tools UPS is using includes Teledyne’s AirFASE flight data monitoring technology, which is capable of reconstructing flights and comparing actual data with recommended values to identify abnormal events and calculate operational trends.

In February, UPS received approval to begin using ChronicX, which is capable of helping aircraft maintenance supervisors to recognize defects faster.

Wagner said one of the key focal points for UPS will be the continued change from a reactive aircraft maintenance team to a proactive one. While the technology is doing its job, providing all of the data it needs, it will also have to continue to modernize the culture of its aircraft maintenance to be more accepting of the use of data informing changes on the aircraft. That’s a much different process than it’s used to — seeing pilot reports and reacting, versus receiving data that shows a trend toward an impending service failure and changing a part before it fails.

“The acceptance of data for proactive maintenance — we see the resistance. People are used to using logbooks and handwritten info, and react to that,” said Wagner. “The thing with that is, they may not see a logbook write-up. We’re asking them to change something on the aircraft that they don’t see.

“That’s the hardest thing for folks in aircraft maintenance, these guys are looking at a lot of data behind the scenes and are seeing the degradation of systems, and what they tell us we need to believe, versus waiting for a pilot write-up to occur with a handwritten logbook.” GCA Link