CAMO - AIRCRAFT UTILIZATION

What do I need to know?

Each Aircraft Maintenance Manual has an Airplane Utilization section which defines a lower and an upper limit of hours flown per year. This can be for example on a Citation 560XL between 200 HRS and 1,300 HRS a year. As long as the aircraft is operated in that framework the regular inspection intervals are to be used. But what if the aircraft is not used for certain circumstances and falls below the lower limit?

When to use the Low Utilization Programme

If you come to the point where the aircraft is not used for more than the lower limit on yearly hours then often you have to contact the Manufacturer/Type Certificate Holder and ask for a Low Utilization Maintenance Program (LUMP). Some Manufacturers do provide a LUMP as standard within the Aircraft Maintenance Manual or seperately.

If the low utilization is only temporarily for example if the aircraft was in storage due to a sales process and was therefore not flown more than the lower limit its always a good idea to contact your authority to discuss this matter as it will save you time and money when you have to move into the LUMP and out again in a short time period.

What changes in the LUMP

So when your aircraft will be operated under the LUMP the major of the task intervals will change from hourly to monthly intervals due to the low hours the aircraft is flying. This can drive up the costs of the maintenance on a great level since you have to do certain inspections more often than when you operate on the regular maintenance program.

Finally, when to move into the LUMP it depends on the actual hours flown in the past year, which to evaluate is part of your aircraft maintenance program effectivity analysis which should be done on a yearly basis, and on the planned flight hours forecasted for the coming year.

When in doubt it is always good to discuss this with your authority and with the Manufacturer/TC Holder to make sure the aircraft will be maintained in the best practical way.

"Please note this is a practical guide and for information only. Please refer to your company procedures and official documents."