At Dallas Airmotive, we often get questions from customers regarding TFE731 inspection intervals and at what point does an engine really need to come into the shop. We understand these intervals can be confusing due to the range of engine models they apply to and that the service bulletins issued can also extend inspection intervals. A simple logbook review with your Regional Engine Manager at an authorized TFE731 service center can answer questions about yourengine’s inspection intervals as well as highlight the opportunities to extend the inspection intervals by accomplishing specific service bulletins. For additional explanation, we’ve outlined the basic guidelines that clarify TFE731 inspection intervals below.

In general, there are three basic factors that will drive your inspection interval: Major Periodic Inspections (MPI)and Core Zone Inspections (CZI) inspection intervals laid out in the Line Maintenance Manual (LMM), service bulletins, and the life limits on key engine components.

Engine Intervals for TFE731 -20/-40/ -50/-60 Models

Resource for information: Light Maintenance Manual 7 Ch 5-20-00 scheduled maintenance checks Table 801

A Few Notes on these Engine Intervals

• -20/-40/-60 series engines are either 2,500 MPI/5,000 CZI or 3,000 MPI/6,000 CZI intervals based on specific service bulletin compliance.
• -20 series engines with engine serial number P116487 have upgraded internal parts to qualify for the 3,000 MPI/6,000 CZI extended hour intervals, but may require a few other very simple external bulletins to make the interval extension official. Our experts can clarify whether your engine qualifies for the extended inspection intervals currently.
• -40 and -60 series engines will have 2500 MPI/5000 CZI intervals unless service bulletin 72-5194 has been completed along with several other accompanying bulletins as well.
• All -50 and -40BR-1B engines are 3000 MPI/6000 CZI intervals.

Engine Intervals for TFE731 -2/-3/-4/-5 Models

Resource:

For TFE731 -2/-3/-4/-5 engine models, Service Bulletins dictate the inspection interval.

A Few Notes on these Engine Intervals:

• Almost all -2 and -3 engines that have not been upgraded to -2C/-3C/-3D have 1,400 MPI/4,200 CZI intervals.
• All -2C/-3C/-3D engines have a 2,100 MPI/4,200 CZI maintenance schedule.
• The -4/-5 engines are either 2,100 MPI/4,200 CZI or 2,500 MPI/5,000 CZI intervals, depending on which service bulletins have been accomplished.

One additional note: You can fly 100 hours beyond your scheduled MPI hours and 200 hours beyond your scheduled CZI on all TFE731 engine models.

As always, individual engines may vary from the table above depending on the service bulletins completed on the engine. Our experts can help if you have any questions.

For more information, please visit DallasAirmotive.com or HSaviation.co.uk.