Don’t Leave Money On The Table

Accurate prediction of helicopter maintenance costs is a complex task with many factors to take into account. At companies of all sizes, it’s common to have some degree of cost underestimation, but at smaller firms, the magnitude of ongoing underestimation is generally much higher. 

The reason that tends to be the case — and also the solution to the problem — can be found in a glaring in-house disconnect, explained Beth Christianos, aircraft maintenance engineer and director of maintenance at Leading Edge Aerospace in Vernon, B.C. There’s also good news in that this disconnect is fairly easy to bridge.

“A large number of owner-operators at smaller firms may be overlooking a valuable existing resource that can dramatically improve their maintenance cost forecasting,” Christianos explained. That resource is the data analysis skills of their engineers, she said, adding that “it’s interesting to see how many companies are leaving this stone unturned.”

Episode 30 – Rotor Maintenance Mastery: Beth Christianos of Leading Edge Aerospace Part I

In short, a “silo framework” can exist in some companies where the financing department is looked upon as taking care of all the numbers, and the maintenance department is looked upon as responsible for their hands-on tasks and nothing else. This is coupled, said Christianos, with a potential lack of understanding about the scope of the knowledge and skillsets that engineers possess. “Your aircraft maintenance engineers aren’t grease monkeys,” she noted. “They are highly-trained professionals who can and should be contributing to the number crunching, working much more closely with your finance department.” 

In other words, “there’s this perception that the pilots bring in the money and the engineers cost money,” she explained. “We should change this.” Said another way, the cost of a maintenance department should therefore not be viewed simply as a necessary evil, but rather as something to invest in. 

And while the ability of engineers to decipher and translate data will greatly assist finance departments in cost forecasting, it can easily provide more benefits. Christianos explained that when engineers “are properly resourced and not pressed for time because they’re running from maintenance crisis to maintenance crisis, they can provide a large amount of data that will help not just in proper budget forecasting of maintenance costs, but in protecting the aircraft asset over the long term and extending its lifespan.” Using this strategy, she said “the entire company reaps the rewards.”

Running the run sheets

The raw data that engineers at bigger firms examine and analyze for their finance departments is found in component run sheets. These run sheets are updated daily by the flight operations department, which also works closely in this area with the maintenance department. But Christianos said that at larger companies, engineers actively analyze the sheets and communicate their findings to finance.

“At the bigger companies, the engineers are tracking and reporting that ‘We are 500 hours away, 100 hours away, then 50 hours away’ and so on, for a given part to be replaced or overhauled, for all the components and subcomponents,” she explained. “They share the data, and they are constantly figuring out what the operation needs and providing it. The finance department needs the same data on upcoming component overhaul or replacement, which they can cost out and account for in the budget, and the maintenance department needs the funds to make sure there are spares on the shelf in a timely manner — not too soon, not too late. So, they both need to look at how many flight hours are forecast to be logged over an upcoming period of time. Then they can analyze how fast they will run through the hours a given component has remaining. This way, everyone is prepared for the cost of the component overhauls or replacements as they come up, and to do the actual work.” 

Smaller companies that want to bridge this gap and get away from constant crisis management need to therefore give engineers the time required for both data analysis and communication of that analysis.  

Besides precise tracking of components (with logged flight time and future flight hour forecasts) and inspections, accurate maintenance cost prediction hinges on understanding the impact of flying environments. Factoring in the added costs of operation in salty and/or sandy conditions (increased wear and corrosion of components, increased inspection frequency and so on) becomes easier the longer you operate in those conditions. But accurate prediction can be challenging for those without much experience, and flying environment costs can also vary to some extent across models. 

Similarly, helicopters carrying consistently heavy payloads will likely experience faster rates of component wear, and if those payloads are intermittent rather than steady, it’s more challenging to predict maintenance costs. And similarly to the run sheet scenario, Christianos pointed out that in cases where the engineer assigned to look after that helicopter for the season is not communicating payload-related analysis to management, it’s another example of invaluable insight “gold” that’s sitting right in front of the company and being overlooked.  

And while scheduled helicopter maintenance events are governed by the maintenance manual and set inspection intervals, unscheduled maintenance can always crop up, explained Ron Garis, manager at Conklin & de Decker, and Kevin Mawhinney, Conklin & de Decker helicopter program manager. Jet Support Services (JSSI) acquired Conklin & de Decker in 2018. 

Inspection tracking

Christianos noted that cost of inspections can be predicted using historical data, factoring in time spent on past inspections, corrective actions taken, and defects rectified (such as worn bearings or corrosion damage). Time between overhauls (TBO) for components and service life limits (which vary across components) are measured in hours, cycles, or calendar time — and while new component costs are set by the manufacturer, maintenance costs vary if overhaul or component exchange is needed. 

Todd Reicher, an aircraft maintenance engineer and quality assurance manager at Leading Edge, explained that “accurate tracking, and frequent reviews of the tracking of these components ensures inspections aren’t missed, and full life limits are utilized before replacement or overhaul.” 

Because issues found during inspections contribute to cost fluctuation, Garis and Mawhinney point out that more corporate helicopter operators are choosing to enroll in hourly cost maintenance (HCM) programs, which JSSI offers to the business aviation industry. Indeed, half of Safran Helicopter Engines’ engine flight hours are now covered by the manufacturer’s support-by-the-hour service. Pratt & Whitney Canada (P&WC) is also seeing growing interest in its HCM programs.

HCM can help reduce the cost risk of future maintenance and also stabilize the maintenance budget. That is, this maintenance payment structure goes beyond a predictable fixed-fee and allows for more straightforward planning. “It provides visibility on engine operating costs and smooths financial flows,” said Safran spokesperson François Julian. 

John Lewis, executive director of helicopter and small turboprop customer programs at P&WC, said their HCM programs “can deliver double-digit percentage cost savings over a time and material approach, particularly for events like hot section inspections and overhauls. Savings increase if an aircraft-on-ground or unscheduled event occurs.”

P&WC offers several programs tailored to deliver optimal cost savings to customers with different fleet sizes. Some HCM plans also offer priority (faster) parts supply services, and more and more HCM programs are now integrated into other digital services such as health monitoring.

Health and usage monitoring systems (HUMS) are becoming increasingly popular across the aviation industry, and can greatly improve maintenance cost prediction accuracy. These systems measure and monitor factors such as vibration levels, rotor performance and engine health parameters to detect problems proactively and predict failures before they occur. As these systems become more widespread, manufacturers will also be using this data to provide insight into determining various issues, for example, whether an overhaul period can be extended. 

Mawhinney also explained that “the expected future inclusion of HUMS-based predictive model for both scheduled and unscheduled maintenance can provide both increased aircraft availability and reduction in repetitive, possibly unnecessary, maintenance downtime.”

Looking further forward, Christianos pointed out that it’s eventually expected that artificial intelligence-driven predictive analytics will emerge in helicopter maintenance planning, providing additional insights and even higher maintenance efficiencies.