|James Christopher - Licensed Aircraft Maintenance Technician / Manager, Maintenance Programs at Delta Air Lines|
Delta Air Lines judicious approach to capital investments in aircraft has led to a complex array of aircraft types and configurations within the fleet. The Technical Operations division of Delta is tasked with maintaining this complex fleet and leads the industry by providing the most reliable operation in the world while preserving the uncompromised safety necessary in air travel.
Sustaining this performance is not without its challenges as exhibited by one particular C Check maintenance base. This base is tasked with performing C Check maintenance on the MD-88, MD-90, B717, and A330 aircraft as well as occasional B767 C Checks. Historically this maintenance base has been extremely reliable and performance was typically on time and in scope. Currently the base is having difficulty delivering their projects on time with the resulting overdue checks being assigned to outside vendors.
The site previously found success by employing some Critical Chain methods to manage their checks but moved away from those successes as time passed and personnel changed. Our focus was to reintroduce Critical Chain to the site. To gain buy-in and support for sustaining any efforts beyond the initial deployment we attempted to generate a grass-roots implementation of CCPM that would be driven from the supervisor level.
Why was there a need for Change – what was the catalyst for change or why did you finally decide it was time to take action?
The Turn-Around-Time (TAT) for the maintenance visits being performed by this site were slipping and the negative trend was getting worse. The percentage of visits being returned late was growing and the amount of time late was also increasing. This negative trend was impacting the business by driving the overdue maintenance visits to outside vendors for accomplishment creating a double negative for the organization. The work redirected to the vendor created additional direct costs to the organization and the transfer of work drove up the unit cost of the work being performed by the existing internal facilities and resources.
What needed to be changed? – or what was the problem as you see it?
The degrading TAT was resulting because of the following reasons:
- The work in progress in the site was beyond their capacity.
- Resources were assigned based on a subjective prioritization system that valued completion of external contract work over internal work.
- Any remaining resources were assigned based on which visit was closest to its due date.
- The planning that was completed for each maintenance visit did not adequately capture the resource or duration requirements necessary to build an achievable plan.
- The existing planning tool did not provide the clear concise priorities that the supervisors desired to manage each individual maintenance visit.
- Disagreements between local and corporate planners was creating friction in expected performance and resentment over imposed due dates.
- There was no plan to account for variability in each maintenance visit.
What was the intended future state? – if you could wave a magic wand and teleport into the future, describe a future characterized by desirable elements not present today (before the start of the implementation)
The first element necessary to achieve the future state was that ability of the site to control their work in progress. This had to be done in a manner that would protect the organization from the uncertainties of not knowing when the next maintenance visit would be inducted. The site could say "wait” but would also have to say "until when”.
The second element necessary for success was determining the appropriate amount of work the site was capable of. This could then be adjusted based on the level of throughput desired by the organization.
The third element was an equalization of the organizational prioritization system or a system that understood the overall needs of the business as well as how those priorities affected the entire business.
The fourth element was the need for a plan that could prioritize the work on each maintenance visit and account for the variability of those visits.
All of these had to happen while maintaining the robust quality and safety of flight requirements of the company and the federal oversight agencies.
How was the transformation accomplished?
Workshops were held with the local Subject Matter Experts (SME) and the site managers to develop a CCPM network plan for each visit type. The involvement of the SME and management personnel was as much to gather their input as to gain their buy-in of the solution. Each network provided a plan to flow its particular check allowing for the proper prioritization of work on the individual checks and the appropriate application of stagger to the induction of maintenance visits planned for the site.
Direct support was provided for the on-site personnel during the Proof of Concept and full implementation phases to teach proper CCPM methods, demonstrate software usage, and answer questions.
How are we measuring, refocusing, sustaining and growing the change?
The Turn Around Times, labor man-hours applied to each maintenance visits as well as overall cost of each check is being monitored. The number of C Checks that are being outsourced to vendors is reduced and the use of card burn down rates has been eliminated. The importance of flow is emphasized by focusing the individual contributors on the overall objectives of the site through the use of fever charts. Focus on individual Bay performance is replaced with the performance metrics of the entire site.
What were the lessons learned?
Involving the SME and site management in all of the decisions about the network plan increased their buy-in and ownership of the final product. They would not have accepted a plan we developed independently and forced them to use.
The site had encountered some previous success using a limited application of CCPM and for the most part they were eager to try it again. They knew the site was failing at delivering an on time product and were eager to perform well and saw CCPM as their chance to do that.
Initial modelling of the check has validated that the TAT can be reduced and further, the TAT estimations are utilized by the Planning group to determine future aircraft check durations and induction dates.
There were contractors working in maintenance positions at the site who held varying degrees of aptitude and motivation. We had to bridge the trust barriers between the full time and contract employees.
The site leaders historically used a work management system that allowed them to see the work to be accomplished in a very visual and interactive environment. The planning tool they were currently using, which lacked CCPM capabilities, had removed that visibility from them and any new solution needed to provide ways to replicate those visual aids.
The request for assistance came from lower within the site management team. We had to win the support of the site General Manager and his Director to get approval to proceed.
How each obstacle was overcome?
A lot of time was invested training the SME and lower level managers in the basics of CCPM and they were encouraged to discuss those advantages with their higher level managers. A future reality was painted for the General Manager and his interest was piqued to the point that he was asking for additional training so he could explain it better to his boss.
We also earned the confidence of the management group by designing a proof of concept into the transition process. The proof of concept allowed us to validate the logic of the network plan we had developed and gave the management team the confidence that it was a sound plan.
James Christopher has over 27 years experience as a licensed Aircraft Maintenance Technician. Spending time with both Delta and Northwest Airlines involved in heavy and intermediate maintenance visits as well as line maintenance operations. He is currently the manager of a group within Maintenance Programs at Delta Air Lines tasked with improving maintenance packaging and check performance for all scheduled maintenance on Delta’s fleet of over 700 aircraft.
Jim received his Project Management Professional certification from the Project Management Institute in early 2014 and is currently pursuing additional training in Constraints Management. The PMP and especially the TOC philosophies have allowed him and his team to deploy alternative methods of check improvement that allow more creative approaches to problem solving than traditional means.