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Appendix D

Maintenance Management Tools

The following paragraphs discuss some of the procedures/tools used by maintenance managers to ensure an efficient workflow throughout the unit. Some of these procedures/tools (tub file, DA Form 2405, manual flowchart) may be replaced by the automated management system-ULLS-A. ULLS-A provides maintenance managers with more and faster information, however, it does not guarantee good maintenance management. PC must ensure flight operations, flight companies/ platoons, maintenance, shops, QC, and technical supply work together to provide safe and reliable aircraft for missions.


D-1. The PC officer should conduct daily aircraft PC meetings. Representatives from the flight platoons/companies (leader/sergeant/ maintenance officer) should attend. These meetings should also be attended by representatives from QC, technical supply, maintenance platoon, and shops. The major goal of each PC meeting is to identify any aircraft maintenance problems as soon as possible. PC must work with the flight platoon/company representative to coordinate the support necessary to correct the deficiencies in the least amount of time with the highest possible aircraft readiness rates. Flight platoon representatives should bring their most current aircraft status reports to the meeting to update the aircraft maintenance officer. They should also be prepared to discuss any special maintenance or supply support required for their aircraft by QC, shops, maintenance platoon, technical supply, or the AVIM company.

D-2. The aircraft maintenance officer will tell the flight platoon representatives which aircraft will be worked on next, which aircraft need to be moved to the AVUM or AVIM hangar, and which, if any, special aircraft preparations the crew chiefs require. Representatives should also discuss deviations from the flying schedule and make minor changes to the schedule as needed. These changes allow for mission change and for scheduled aircraft anticipated to be grounded for maintenance or services during the time of missions they were to support.


D-3. A scheduling system that promotes efficient workflow is needed to ensure that customers receive their aircraft with the least possible delay. Many factors must be considered to develop a scheduling system. These factors may include the current workloads and priorities of the supported units, the availability of tools, and the supply of major components, parts, and hardware.

D-4. A successful PC operation requires a scheduling system and preplanned workflow. The PC element must track the following information to establish maintenance workweek priorities compatible with the unit's mission:

  • Mission requirements and priorities of supported commanders, to include numbers of aircraft and specific capabilities required for those aircraft.
  • Aircraft maintenance flow, by flying hours remaining for each assigned aircraft until upcoming scheduled maintenance inspections.
  • Current total number of flight hours, status of avionics and armament, and the operational status of each assigned aircraft.
  • AVUM-level work in progress and work deferred.
  • AVIM-level work in progress and work deferred.
  • Time-change requirements for components, by individual assigned aircraft tail number.

D-5. Coordinating, planning, and scheduling are closely associated. Experienced PC officers and NCOs handle planning and scheduling. They should specify in detail the work required to achieve the desired results. When preparing intrashop DA Forms 2408-13-2, 2408-13-3, and 2407, PC should coordinate closely with QC personnel. DA Forms 2408-13-2, 2408-13-3 and 2407 should specify in detail all work required or inspections to be performed. The following procedures apply to a typical PC section:

  • Prephase Test Flight. Whenever practical, maintenance test pilots should perform a prephase test flight on aircraft scheduled for phase or periodic maintenance. The maintenance and the PC officers should review the results to determine which platoon or section will do the required maintenance. Faults noted on the appropriate phase checklist become a part of the phase inspection. The TI assigned to make the phase inspection on the aircraft should accompany this test flight when possible.
  • Aircraft Arrival. When the aircraft arrives at the maintenance activity, PC receives DA Form 2407 and the aircraft's equipment logbook assembly (records). PC personnel review the DA Form 2407. When they accept the aircraft, they log it on a DA Form 2405 and set up a records file jacket. They send the records file jacket, containing DA Form 2407 and the logbook assembly, to the QC section. Units using ULLS-A will follow the procedures in the ULLS-A end user manual. AVIM units operating under the SAMS-1 will follow the procedures outlined in SAMS-1 end user manual.
  • Paperwork Flow. PC personnel will complete Block 24 of DA Form 2407. A copy of the receipt and the carbon of the inventory sheet go to the supported activity's representatives. These personnel direct the workflow through the various shops, entering all maintenance requirements on the PC board. The records file jacket is placed in the PC section of the tub file. As work progresses through the shops and sections, QC personnel conduct in-progress inspections. QC personnel conduct inspections on intrashop maintenance requests as they are completed and route them to the PC shop. Faults are recorded on DA Forms 2408-13-1, 2408-13-2, 2408-13-3. PC personnel extract the necessary information from the completed intrashop maintenance requests and DA Forms 2408-13-1, 2408-13-2, and 2408-13-3 and enter it on DA Form 2407.
  • Final Inspection. PC personnel receive and consolidate all accumulated documents relating to the maintenance performed on the aircraft. This indicates that the required maintenance is complete. They then request the QC shop to make a final inspection of the aircraft, and they furnish the necessary paperwork, forms, and records for this purpose. This inspection, plus the recorded in-progress inspections, ensures quality maintenance and an airworthy aircraft. It also verifies that inspection plates and panels have been properly reinstalled and that the aircraft has been properly serviced and cleaned. QC personnel also check forms and records in the aircraft's equipment log assembly (records) to ensure that all entries are neat, correct, and up-to-date.
  • After the final inspection, the TI signs or initials and enters the Julian date in Block 26 of DA Form 2407. This indicates that he has inspected the aircraft and verified that all services and repairs have been done. If the maintenance or repairs requested are recorded in the faults or remarks block of DA Form 2408-13-1 as a red-X item, the technical inspector must sign in the correcting information block. This signifies that he has inspected the items and that they have been corrected. The TI determines whether a test flight or MOC is required according to TM 1-1500-328-23 or appropriate aircraft manuals. If so, he notifies PC that a test flight is required. The basic issue item list gear and loose equipment required for test flight purposes is removed from the loose equipment storage area and reinstalled in the aircraft. If an MOC is required, it will be annotated in the aircraft logbook.
  • Post-Test Flight Inspection. If a test flight is performed, the test pilot will perform a post-test flight inspection of the aircraft. If maintenance test pilots do not release the aircraft for flight, they make the required entry on DA Form 2408-13-1. The aircraft is again prepared for a test flight. All equipment belonging to the aircraft is placed in the aircraft after the test flight, and then the aircraft is released. QC personnel return the completed paperwork, forms, and records to the PC shop. PC personnel notify the owning unit that the aircraft is ready for delivery.
  • Release of Aircraft. The QC personnel or crew chief and the supported activity's representative perform a joint inventory of the BIIL gear and loose equipment. The maintenance request clerk enters in Column h of DA Form 2405 the Julian date when the aircraft maintenance was completed. The supported activity's representative completes Block 27 of DA Form 2407 signifying acceptance and delivery of the aircraft.


D-6. Phase/periodic inspection planning is a critical part of mission readiness for aviation units. Aviation commanders/PC must ensure aircraft phases are planned well into the future. Although many factors influence the best time for accomplishing aircraft phases, training exercises and deployments can have a major impact on the unit's bank time. Flying more than one or two aircraft into phase at a time can severely reduce the unit's operational readiness. To alleviate crisis management, the unit's flying hour program, deployments, training, bank time, and the availability of resources (tools, maintenance personnel, repair parts, special equipment) must be carefully considered when planning phases.

D-7. The aircraft flowchart is an important tool for scheduling aircraft for phase and for deciding which aircraft should fly certain missions. Figure D-1 shows an example of a typical flowchart for a UH-60 unit. The diagonal line represents the optimum bank time, or time until phase, for each individual aircraft. This flowchart demonstrates a unit with good total actual bank time (above optimum) and good separation between phases (periodic inspections).

Figure D-1. Flowchart with Good Bank Time

D-8. If every aircraft were exactly on the optimum line, this would be the ideal bank time, or 2,500 flying hours, available. Obviously, this is unrealistic as some aircraft will be above the line and some will be below the line. Therefore, the only way to obtain the actual bank time is to add up the total flying hours remaining on all aircraft until the next phase/periodic inspection. Thus, total actual bank time is only a relative indicator of how well the maintenance scheduling process is working compared to the ideal, or optimum bank time, formula. Under heavy flying conditions (surge), bank time available will obviously be lower than desired.

D-9. Figure D-2 shows a flowchart of a unit with less than the optimum bank time. This unit has 1 aircraft in phase (971) and 3 aircraft within 10 hours of phase (970, 988, 989). This unit has aircraft "stacked up" waiting for phase. Even though this unit may have a good operational readiness rate, it is unable to schedule certain aircraft for missions because of low hours. The effectiveness of the unit is reduced.

Figure D-2. Flowchart with Less Than Optimum Bank Time

D-10. The flowchart is a very simple, but effective method that has been used successfully by maintenance officers. ULLS-A provides a flowchart to assist maintenance managers in scheduling maintenance. The proper use of a flowchart—

  • Prevents an unnecessary backlog of scheduled maintenance inspections under normal conditions.
  • Prevents a corresponding sudden surge in requirements for aircraft parts.
  • Allows the unit maintenance officer a degree of control over individual aircraft hours flown.
  • Provides a graphic depiction of future scheduled maintenance requirements.

D-11. The following rules should be observed when using the sliding scale maintenance scheduling method (flowchart):

  • Update the chart at least once each day that aircraft fly (if using ULLS-A, ensure aircraft data is sent to PC daily).
  • Fly aircraft that are above the optimum line to attempt to get them down to the line.
  • Hold (do not fly) aircraft that are below the optimum line to attempt to bring them up to the line or fly minimum number of hours.
  • Count aircraft that are in phase inspection zero towards actual bank time.
  • Count aircraft that are grounded for any reason (other than phase) towards actual bank time.
  • Remember that total actual bank time is only a relative indicator of the maintenance scheduling process.


D-12. In newer TOEs, where missions may be handed down from battalion, maintenance is in one company while flight crews are in another. Therefore, scheduling aircraft for missions requires closer coordination. The use of assigned block time scheduling is a method that aids the maintenance officer in methodically and purposefully flowing aircraft into their normal scheduled maintenance intervals. It also gives the flight companies better mission flexibility.

D-13. In this manner of scheduling, flight companies receive blocks of flight hours per aircraft from the maintenance officer of the AVUM company. For such a system to work, battalion commanders must back up their maintenance officers by ensuring that flight companies do not overfly the given block times. To determine how many hours each aircraft will be allowed to fly during a given period, the maintenance officer uses the following formula:

  • Step 1: Find the average hours per aircraft by dividing the total number of hours to be flown by the number of aircraft to be flown. (Example: 180 hours to be flown divided by 9 aircraft equals 20 average hours per aircraft)
  • Step 2: Plot the average hours per aircraft on the flowchart below the highest-time flyable aircraft. Then draw a line parallel to the optimum bank time line (Figure D-3).
  • Step 3: Compute the difference between each aircraft's current position on the flow chart and the new parallel line (Figure D-4). These figures will now become the maximum amount of flight hours that particular aircraft can fly during the mission. (Example: Aircraft 955 is 26 hours above the lower optimum line (Figure D-4), so it will be given a block time of 26 hours to fly.)

D-14. The benefits of such a scheduling system are the following:

  • Flight companies have flexibility in selecting aircraft for daily missions during the operation.
  • Flight companies can match the aircraft to the mission.
  • It spreads the responsibility of aircraft assignments and staggers the aircraft on a flowchart.
  • The maintenance officer can plan his workload in advance versus having to react to everyday changes in missions and unscheduled maintenance.
  • The flowchart posture should still look good after the operation.

Figure D-3. Step 2 of Block Time Scheduling

Figure D-4. Step 3 of Block Time Scheduling


D-15. The PC board (Figure D-5) is a graphic that displays data concerning aircraft status or shop operations. Information recorded on the board is used to control current operations, plan anticipated work, and measure work performed. Although maintenance managers have quick access to information through ULLS-A, a well-planned and informative PC board (equipment status board) can serve as a highly visible source of information for the commander and other key personnel (such as platoon leaders and section chiefs). It should provide them with information on the progress of work in other shops or sections in relation to work in their activities.

Figure D-5. Example of Production Control Board

D-16. The design of the board should be simple and easy to work with. If a PC board is used, entries on the board must be accurate and prompt. The PC officer may organize the board for his own management style. Some suggestions for entries on the board are the following:

  • Current aircraft status. (this must be updated throughout the day as the status of aircraft change)
  • Priority of work.
  • Status of special tools and equipment. (hoists, tugs, AGPUs, test sets, etc.)
  • Reasons for stopped work.
  • Work awaiting receipt of parts. (can be used to track status of parts for NMCS aircraft)


D-17. This form is used when an automated/computerized work request system is not available. It provides a written chronological record for the supporting activity to identify work requests received and job orders completed. It also contains supplemental information about the type of equipment repaired, the serial number or other identification, the owning unit, and the date (Julian) when the maintenance request was received. Adequate control may require maintaining separate DA Forms 2405 for fixed-wing aircraft, rotary-wing aircraft, and components. Allied equipment may be carried on the DA Form 2405 maintained for the type of aircraft with which the equipment is associated. The purpose, uses, and preparation of this form are discussed in DA Pam 738-751.


D-18. The tub file is a manual system for keeping up with the current status of work requests in a unit. Units may use this system or an automated/computerized system to organize/track work requests. PC is responsible for ensuring an efficient system is in place for monitoring the status of all aircraft/component maintenance work within the unit.

D-19. The tub file is for active maintenance requests, which are placed in records file jackets. The status of a repair job in the shop is indicated by the location of its maintenance request and records tile jacket within the tub file. The tub file is manufactured locally and should be lightweight and portable for use when moving frequently. It should be adapted for use in the field by eliminating sections within compartments and reducing its size. Figure D-6 shows how an in-process file is organized.

Figure D-6. In-process (TUB) File


D-20. When initiated, the maintenance request in its records file jacket is placed in this compartment. The maintenance request remains in this compartment until the following actions have been taken:

  • Initial inspection.
  • Routing of intrashop maintenance requests and DA Forms 2408-13,- 2408-13-2, 2408-13-3 to the responsible sections or platoons.
  • Monitoring or reviewing of the repair parts needed to complete the job. (Disassembly during maintenance may reveal a need for additional parts.)


D-21. If work must be delayed, the maintenance request is placed in its records file jacket in one of the 32 sections in the second compartment. If some administrative matter that must be resolved before work proceeds causes the delay, the file jacket is placed in the first unnumbered section. The remaining sections are numbered 1 through 31. Each section represents one day of the month. If the delay is caused by a lack of parts, the file jacket is placed in the section that corresponds to the requisition date of the parts. This procedure provides a means of highlighting the parts shortage and serves as a reminder for follow-up supply action. It also serves as a means to determine requisitioning time on critical and routine items. This method reveals the time required to process repair parts and put them in the hands of maintenance personnel. Maintenance should not be delayed solely because all parts are not on hand. The work is started without all required parts and the file jacket is placed in the third compartment. However, the highlighting of the parts shortage is continued for outstanding requisitions by placing a strip of manila folder marked with the maintenance request control number in the section that corresponds to the original requisitioning date of the parts.


D-22. When the item is ready to enter maintenance, the file jacket is placed in this undivided compartment.


D-23. This compartment is divided and numbered like compartment 2. When repairs actually begin, the file jacket is placed in the section that represents the estimated date of completion. This alerts PC that the job may not be completed as scheduled. As the scheduled date of completion approaches, PC analyzes the information on the PC board and the daily shop status reports. If it appears that the schedule will not be met, the reason for this is determined and a revised completion date is agreed on.


D-24. When repair is completed, the file jacket is placed in this compartment. It remains there until the final technical inspection/test flight or until a maintenance operational check on the equipment is complete.


D-25. Following the successful completion of the final inspection/test flight or maintenance operational check of the aircraft, the file jacket is placed in this compartment. It remains there until the final joint inventory has been made and the supported unit accepts delivery of the aircraft.


D-26. After the supported unit accepts the aircraft, the maintenance request is placed in its records file jacket in this compartment. The records are retained or disposed of as prescribed in DA Pam 738-751.

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