Mechanics saves Air Force millions
By Kandis Murdock, Tinker Air Force Base Public Affairs
/ Published June 05, 2007
Tinker Air Force Base --
That is the time required to reach a safe breathing altitude if fresh air stops circulating through the cabin of a KC-135 due to an environmental control system failure.
However, officials say the testing process to determine whether in-dock cabin pressure can be sustained for four crucial, life-saving minutes was inefficient and costly.
To ensure this pressure is maintained, a team of mechanics with the 76th Maintenance Wing's 564th Aircraft Maintenance Squadron was able to tighten up the process and save the Air Force nearly $4.2 million annually.
Garry Richey, Oklahoma City Air Logistics Center executive director, honored the team as part of his new Lean Recognition program, a program started to align Tinker with the Air Force Smart Operations for the 21st Century initiative.
Both programs are designed to do things smarter, better, cheaper and faster, Mr. Richey said.
"This is a great example of how our expert workforce is having a direct impact on improving warfighter support," Mr. Richey said. "We're often tempted to say, 'This is the way we do this or that process.' But the pressurization team accepted the challenge to take a fresh, analytical approach.
"The result is a process that is faster, has more quality, and at lower cost. I'm proud of the team. They are true warriors supporting warriors."
Tinker aircraft planner Brian deFonteny, who made the discovery along with six mechanics including Josh Dobbs, Tim Wilson, Larry Adams, Shayne Walden, Shane Spencer and Mitch Calhoun, said before the improvements were made the cabin pressure testing process was repetitive and tedious.
"We were repressurizing aircrafts over and over to pass a four-minute leak down check and 17 of 20 aircrafts still didn't pass after two (tests)," said Mr. deFonteny.
In fact, on average, it took more than four testing events and 171 working flow days per aircraft to make sure the plane was fit to fly.
Mr. deFonteny and his Six Sigma team decided to tackle the issue through a Black Belt training program sponsored by the Lean Institute at the University of Oklahoma.
The program encouraged a statistical approach to problem solving. Over the course of eight months, every element of the problem was researched, data was collected and no inferences were made.
The goal of the program was not to simply repair the obvious problem, but to provide a solution by finding the source of the problem according to the data.
Mr. deFonteny said the logical solution was that all the leaks were not being found, which caused the aircraft to fail the test multiple times.
That was not the case, he said.
The data showed that the leaks were found, but were not being repaired with enough precision.
The mechanics devised a method to add a half pound of pressure while sealing the leak, allowing the pressure to suck the sealant precisely into the gap of the leak.
To tidy up the process, the team also created an 84-point checklist of possible leak points as a guide to identify leaks quicker and prevent overlooking a possible leak site.
"Between the half pound of sealing, plus revising all the paperwork, and training the mechanics on how to find leaks, we are down to one and a half events per aircraft," Mr. deFonteny said.
Not only has the team reduced cabin pressure checks from four to an average of 1.5 checks per aircraft, but they also eliminated 125 working flow days on 48 aircraft annually.
Mechanics can now focus on other tasks instead of constantly fixing leaks, testing and then re-testing the planes. The changes also help ensure the tightest possible air cabin is provided to the customer in a shorter amount of time, Mr. deFonteny added.
While the Six Sigma approach to problem solving is a new approach for Tinker Air Force Base, it is proving to be time well spent when the solution is not overtly intuitive. Data collection drives the decision making and the subsequent results are more reliable in the long term.
This particular Six Sigma Black Belt project was indicative of the changes that can come about when the root cause is addressed rather than just the symptoms related to a production problem.