You're in Singapore...
You timed this business trip to coincide with your SR22’s annual inspection. You dropped the airplane at the Service Center before you left. Now, a week later and half a world away, you get an e-mail from the SC listing 88 discrepancies with repair estimates totaling nearly $25,000, and asking for your approval to proceed.
Now what do you do?
Here's what Savvy did...
The aircraft owner emailed Savvy and attached the Service Center's estimate. He explained that he had never used this particular Service Center before, and in the six years he'd purchased his 2004 Cirrus SR22, his annuals had always cost between $4,000 and $6,000. He was floored by this estimate of almost $25,000, didn't know what to do, and asked if Savvy could help.
As a general rule, Savvy does not take on clients in the middle of an annual inspection, but we decided to make an exception in this case. We asked the owner to email the Service Center, advise them that he'd engaged Savvy to manage the maintenance on his aircraft, and instruct them not to perform any repairs until receiving written approvals from Savvy. Once he'd done this, we opened a ticket on our online system and started managing the annual on the owner's behalf.
We were quite familiar with this particular Service Center, and had seen these kinds of stratospheric estimates from them before. It was clear that the owner hadn't done any due diligence before deciding to use this SC for his annual inspection. Had he done so, he'd have almost certainly chosen a different shop. But that was moot now. His airplane was in pieces. The SC had presented him with an 88-item discrepancy list and a $25K estimate. There was no choice but to deal with it.
How can an SR22 annual cost $25,000?
We went through the SC's discrepancy list and repair estimate. Here are the highlights (or lowlights if you prefer) of what we found:
- Annual inspection flat-rated: $3,645.
- 5-year flex hose replacement: $1,900.
- 5-year fuel drain valve seal replacement: $180.
- 5-year gascolator seal replacement: $150.
- 5-year aileron-rudder-interconnect shock cord replacement: $160.
- 500-hour alternator #1 overhaul/exchange: $1,440.
- 1,700-hour alternator #2 overhaul: $790.
- 6-year/1,800-hour propeller overhaul: $3,720.
- 4-year overhaul of both magnetos: $1,700.
- 2-year main battery replacement: $700.
- 2-year TKS anti-ice filter replacement: $320.
- Annual fuel injector nozzle cleaning: $200.
- Replace cracking TKS prop boots: $860.
- Repair heat damage to lower engine cowling: $940.
- Repair disbonding wing root fairing caps: $950.
- Replace both mufflers, flame cones warped: $2,280.
- Replace ACK E-01 ELT with 406 MHz ELT: $1,750.
- Multiple paint touch-up items: $1,620.
- 50 additional minor discrepancies: $1,425.
Total estimate (parts and labor): $24,730.
Before discussing how Savvy dealt with this mind-boggling repair estimate, it's important to understand Savvy's reliability-centered approach to aircraft maintenance.
Reliability-centered maintenance
Fifty years ago, in the 1960s, aviation maintenance was predicated on the belief—held almost universally by the aeronautical engineers and maintenance experts of that era—that every aircraft, subsystem and component had a predictable “useful life” during which it could be expected to operate reliably, and after which it needed to be replaced or overhauled in order to prevent failures. (Many GA mechanics and aircraft owners still believe this to be true.)
However, research conducted by the airlines in the late 1960s—notably the work of Nowlan and Heap at UAL—demonstrated that this belief was flat wrong in almost every instance they investigated. This resulted in a paradigm shift in the way maintenance was done in the air transport industry. The new "reliability-centered maintenance" (RCM) way of thinking about maintenance included:
- Understanding that the vast majority of failures are not age-related, and that a very large number of them are either infant mortality or maintenance-induced;
- Changing from efforts to predict life expectancies to trying to manage failures;
- Shifting from fixed-interval, time-directed maintenance to on-condition maintenance;
- Eliminating most TBOs and life limits in favor of condition monitoring and failure prediction; and
- Recognizing that that many component and subsystem failures have acceptable consequences, and that “run to failure” is often the best maintenance strategy.
The shift from traditional to RCM-inspired maintenance in the late 1960s and early 1970s was a watershed event. It resulted in massive reductions in maintenance expenditures and scheduled downtime by eliminating most TBOs and life limits and slashing both the amount and frequency of preventive maintenance. To the astonishment and disbelief of most maintenance experts of the time, component failures and unscheduled downtime plummeted.
This defied the conventional wisdom of the time. How could it possible that by doing less preventive maintenance to the aircraft, it actually becomes more reliable?
The Waddington Effect
It turns out that this seemingly counterintuitive result was first discovered during World War II—more than 20 years before Nowlan and Heap did their pioneering RCM studies at UAL—by a brilliant British scientist named Conrad Hal (C.H.) Waddington (1905-1975). The British RAF asked Professor Waddington to investigate the problem of what today would be called “force readiness.” Specifically, the RAF’s B-24 “Liberator” bombers were spending an inordinate amount of time in the maintenance shop, both for scheduled preventive maintenance and for unscheduled resolution of what the British called “breakdowns” or “downs” or “gripes” and that we’d call “squawks.” Obviously, the more time bombers spent in the shop, the less time they could spend hunting and killing German U-boats. At any given time, half of the B-24s would be down for maintenance.
Conventional wisdom held that if more preventive maintenance events were performed on each aircraft, fewer problems would exist—and potential problems could be caught and fixed—and thus the effectiveness of the fleet would surely improve. Conventional wisdom was, as is so often the case, wrong. It would take C.H. Waddington to prove just how wrong.
Waddington and his team started gathering data about the scheduled and unscheduled maintenance of these aircraft, and began crunching and analyzing the numbers. When they plotted the number of unscheduled aircraft repairs as a function of flight time, they discovered something both unexpected and significant: Such unscheduled repairs increased sharply immediately after each scheduled 50-hour maintenance event, then declined steadily over time until the next scheduled 50-hour maintenance, at which time they spiked once again.
When Waddington examined the plot of this repair data, he concluded that the scheduled maintenance (in Waddington’s own words): “…tends to increase breakdowns, and this can only be because it is doing positive harm by disturbing a relatively satisfactory state of affairs. Secondly, there is no sign that the rate of breakdown is beginning to increase again after the 40-50 flying hours, when the aircraft is coming due for its next [scheduled preventive maintenance event].”
In other words, the observed pattern of unscheduled repairs—now known as “the Waddington effect”—demonstrated that:
- The scheduled maintenance was actually doing more harm than good; and
- The 50-hour scheduled maintenance interval was inappropriately short.
The solution proposed by Waddington’s team—and ultimately accepted by the RAF—was the development of an improved maintenance program that:
- Increased the time interval between scheduled maintenance events; and
- Eliminated preventive maintenance tasks that were not demonstrably beneficial.
Once these recommendations were implemented, the number of effective flying hours of the British Coastal Command bomber fleet increased by more than 60%.
How Savvy dealt with the $25K estimate
Savvy meticulously went through the SC's discrepancy list and cost estimates, evaluating each recommendation and estimate as to its merits. We wound up approving some of the items and declining many of them, based on RCM principles. There were a number of iterations between Savvy and the SC over these items. In the end, here's a summary of what was agreed to:
- Annual inspection flat-rated: $3,645.
Approved. Although this was considerably higher than most Cirrus SCs charge for a flat-rate, it turned out to include numerous preventive maintenance items that most SCs charge for separately. So after some due diligence, Savvy accepted this charge. - 5-year flex hose replacement: $1,900.
Declined. Although Cirrus recommends replacement of flexible fluid hoses every 5 years, this recommendation is based on worst-case conditions of an airplane that is relatively inactive and stored outdoors. Because this airplane flew a lot and lived in a hangar, we recommended to the owner that the hoses be changed after 7 to 10 years. At that time, we will recommend that the standard rubber hoses be replaced with Teflon "lifetime" hoses that can remain in service much longer.. - 5-year fuel drain valve seal replacement: $180.
Declined. We recommend that these seals be replaced on-condition (when they start to leak) We see no benefit to replacing them on a fixed timetable. - 5-year gascolator seal replacement: $150.
Declined. Replace only on-condition, for same reasons. - 5-year aileron-rudder-interconnect shock cord replacement: $160.
Declined. Replace only on-condition. - 500-hour alternator #1 overhaul/exchange: $1,440.
Declined. These alternators have a very high infant-mortality rate. If the alternator made it to 500 hours without failing, then it's one of the good ones! Last thing we want to do is replace it with a new one that might fail in 50 or 200 hours. We recommend running this item to failure, or at least to 1,000 hours. With a fully redundant electrical system (two alternators, two batteries), we do not consider alternator failure to be a safety-of-flight item. - 1,700-hour alternator #2 overhaul: $790.
Declined. This item is not even required equipment for VFR operations. We recommend running it to failure. - 6-year/1,800-hour propeller overhaul: $3,720.
Declined. The recommendation to overhaul every 6 years is based on worst-case assumptions. Because this aircraft flies so much and is hangared, we recommend deferring the prop overhaul until engine overhaul time. - 4-year overhaul of both magnetos: $1,700.
Declined. We recommend doing an IRAN (inspect and repair as necessary) of the magnetos every 500 hours. There is no valid reason to do it on a calendar-time basis, nor any reason to overhaul rather than repair. Typically the 500-hour IRAN costs about $400 per magneto, less than half the cost of an overhaul. - 2-year main battery replacement: $700.
Declined. We recommend replacing the battery on-condition, and find that they often last for 3 to 5 years. - 2-year TKS anti-ice filter replacement: $320.
Declined. We recommend replacing the filter only if the TKS system is exhibiting operational problems. These filters normally remain spotless because nothing but pure TKS fluid flows through them. - Annual fuel injector nozzle cleaning: $200.
Declined. We recommend cleaning fuel nozzles strictly on-condition, only if the engine monitor data indicates that there is a mixture distribution problem. - Replace cracking TKS prop boots: $860.
Declined. We requested photos of the prop boots, and determined that the cracking was cosmetic. We recommend replacing the boots only if they start to disbond from the propeller blades. - Repair heat damage to lower engine cowling: $940.
Approved. We requested photos of the engine cowling damage and determined that it was serious and needed to be repaired. - Repair disbonding wing root fairing caps: $950.
Approved. These fairings are held on by two-sided tape. They needed to be re-adhered to prevent them from being lost in flight. - Replace both mufflers, flame cones warped: $2,280.
Modified approval. We directed the SC to send the mufflers out for repair rather than replace them with new, reducing the cost by about 50%.. - Replace ACK E-01 ELT with 406 MHz ELT: $1,750.
Declined. We recommended the owner wait until the ACK E-04 ELT was approved, as it will be a drop-in replacement for the existing E-01 ELT, and will be one-third the cost of the unit proposed by the SC. - Multiple paint touch-up items: $1,620.
Declined. We determined these were purely cosmetic items, and after consulting with the owner, decided this could be deferred. - 50 additional minor discrepancies: $1,425.
Most of these minor repair were approved.
By the time the process was complete, the final invoice from the SC came out to be approximately $8,000. Certainly higher than the usual Cirrus SR22 annual, but nearly $17,000 less than what the SC had estimated.
The owner was both thrilled and relieved. He wisely vowed never to use that particular Service Center again.
Savvy's annual maintenance management service fee for a Cirrus SR22 is $750. We almost always save our clients many times that much every year in reduced maintenance costs. We can't promise to save you $17,000 a year, of course—although we have saved some of our clients twice that much—but we can promise that Savvy won't cost you money, it'll save you money, year after year. Cost is not the only issue, of course. Most Savvy clients feel that having a world-class team of maintenance experts to advise them and "watch their six" is priceless, especially when maintenance issues arise away from home base.