KC-135 Structures Gate implements new plan to manage workload

Published June 17, 2016
By Kimberly Woodruff
Staff Writer

TINKER AIR FORCE BASE, Okla. -- When Tinker Air Force Base units are challenged to meet a requirement, they don't let anything get in their way of getting the job done.

In 2009, the 564th Aircraft Maintenance Squadron was asked to increase the programmed depot maintenance workload for the KC-135 to achieve an all-organic PDM capability by Fiscal Year 2012.

That same year, the 564 AMXS was successful in producing 47 KC-135 aircraft and increased production in following years with 55 aircraft produced in FY10 and 64 aircraft in FY11 to meet the 2012 all organic goal. The unit closed out FY 2015 with a record 70 organically produced aircraft.

Increased workload combined with fiscal constraints required a healthy dose of innovation, which came in the form of the AFSC Way...a production philosophy based on Continuous Process Improvement. Since 2009 the 564th AMXS had operated with a Two-Track Flow production machine consisting of two different types of structural repair plans; speedy or Extended Flow Aircraft (EFA). Speedy aircraft could complete the structures gate in less time as opposed to extended flow aircraft planned for a longer flow. This enabled airplanes with fewer issues to proceed through the PDM process quicker maximizing resources.

The 564th AMXS and System Program Office expected only half of the aircraft to come in requiring major structural repairs (MSR) resulting in an EFA gate and the other half to flow through the speedy gate for 2016. However, 2015 ended with 70 percent of the aircraft being EFA, driving up the number of docks needed to complete the work and the time the aircraft was on station. "The KC-135 airframe is over 50 years old and we are seeing more repairs as they continue to age," said Mr. Estorga of the 564th AXMS. "The majority of the repairs are structural in nature and fall within the structures build-up gate of the KC-135 production machine."

Increased structural repairs on the KC-135 aircraft are a major hurdle for the 564th AMXS. By the end of 2015 MSRs were on the rise and 93% of aircraft projected to produce in 2016 were extended flow aircraft. "We had significant challenges going into fiscal year 2016" said Col Kenyon Bell, Commander of the 76th Aircraft Maintenance Group. "Our enterprise team (SPO, supply chain, stellar 564 AMXS workforce) learned and adapted to the new landscape to meet customer requirements through our proven Continuous Process Improvement initiatives. We are confident this approach will get us to 76 aircraft for the year."

To overcome the increased demand generated by the increase in MSRs, the 564th took a page from "The AFSC Way" book and implemented a new plan.

First, they developed a new production machine, or script, to refine deliberately planed work. The new production machine anticipated a 93% percent major structural repair rate, so the two-track flow plan was stopped. A standard flow day target for the structures gate was applied to all incoming aircraft.

A second tool to overcome the increase was to implement a "queue" to manage the workload. "Queueing" aircraft is a deliberate decision to not apply resources to a particular jet. This ensures resources such as personnel and equipment are not spread too thin and enables the unit to efficiently manage Work in Process (WIP). This technique ensures one aircraft completes a particular process prior to an additional aircraft starting the same process. So far this year, there have been up to three aircraft queued to the structures gate.

"Queue enabled the squadron to position the aircraft for successful completion of the structural requirements," said Mr. Estorga. "Prior to the implementation of queue, aircraft would start the structures gate outside of facilities designed to support MSRs. MSRs require the aircraft to be jacked. Due to facility constraints in Building 3001, trapping aircraft on jacks is a major concern."

The 564th AMXS also used subject matter experts and continuous process improvement events to refine the overall PDM process and maximize the number of repairs that can be completed at the same time. One of the most successful projects was the Major Structural Repair Concurrency Work Event.

Structural maintenance subject matter experts worked together with KC-135 System Program Office engineers to create a plan to maximize concurrent structural repairs, resulting in more work getting done safely in the same amount of time. These solutions are cataloged in a "Concurrency of Work Matrix" that identifies tasks that can be completed concurrently and the number of flow days required to complete the job.

As a result of the event structures has reduced flow days from 72 days at the end of FY15 to 54 days currently and driving down to a high 40's day average. Work in progress in the structures portion of PDM has enabled the structures gate to meet the increased workload requirement. Refinements in the structures gate are key as this is the most complex and labor intensive of the 5 production gates used to move a KC-135 though PDM.

Refinements in each gate lead to a more efficient overall process, ultimately resulting in more available aircraft for our nation's defense.