By Vern Berry
I have been blessed with a variety of experiences in my aviation career including at one time DQC for a major airframe maintenance and repair organization (MRO). I took the job because I had never worked for a major repair station but assumed that having worked with them for years as an auditor and operator’s representative; I pretty much knew the score.
Well, so I thought anyway. My experience concerning MROs and the circumstances that make them the peculiar animal that they are was hard won and based on the patience and support of persons who worked with me during my time there.
MROs working on any type of aircraft for Part 135 or 121 entities must comply with the certificate holder’s processes. They must be approved to work on that aircraft type. They must have current repair data and tooling. Their people must be trained and qualified — then authorized to work on the aircraft by the operator’s quality unit after a thorough audit. Operators are required to provide training on their procedures. Operators having a D091 Operation Specification for substantial maintenance vendors must show that the MROs satisfy the requirements of the operation’s specification’s standards to their certificate management unit. And all that is supposed to happen before you drive through the door.
Once the operator’s airplane is sitting on the hangar floor, one would think that if the operator has done all that work in advance to qualify the vendor then why should I be concerned? Ah, but therein lies the rub.
As the only airplane in the hangar — it’s all very simple; just focus our efforts on one aircraft and the customer’s expectations. However, when there are multiple hangars, aircraft lines, and aircraft with multiple competing customer expectations and processes, things become very complex.
Production and controls
In the real world — airframe repair and overhaul is big business and the driver of that business is man-hours. An operator’s maintenance representative will be checking each day for the labor numbers related to work progress. Key to this is the repair station’s assessment of the routine maintenance and its subsequent estimates for non-routine maintenance.
Lacking knowledge of these in advance can result in unwelcome surprises during the check and sticker shock once the aircraft is finished.
Aircraft are assigned a man-hour budget that may or may not reflect the cost to the owner/operator but will be the time assessed by the MRO as adequate to complete the work. It reflects the margin between cost and profit. Project managers and supervisors driven to make their project shine to upper management work to the schedule and within their man-hour budget. Aircraft are staffed to this budget. Repair stations make their money on this margin and, in today’s economy the margins can be very thin. Finishing an airplane at or below budget makes the project/check manager look pretty good. It’s not necessarily bad for the customer so long as quality does not suffer.
The decisions made before and during the project in support of these constraints place constant pressure to move the aircraft along. Schedule slots are often assigned to backlogged aircraft by date in a nose to tail fashion. They are waiting for the spot on the hangar floor when your airplane is complete. Management monitors the work flow to assure that the revenue stream is working to projected plans. Pressures to move the aircraft drive up the risk of quality and safety failures related to workarounds and substandard work.
When multiple types of aircraft are in check at the same time things become complex — resources have to be scheduled across various lines in accordance with each aircraft flow plan. The project manager seldom has all he needs — he has to work with other managers who have the same requirements. Therefore there is competition for internal resources and this competition can be intense.
In the aviation world, risks we accept define our corporate culture and affect our day-to-day expectations