TFE731 Winter 2006

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• Ignition Unit Replacement for MSP Operators
• ECTM Kits P/N 831702-All for N1 DEEC
• AD 2005-05-15, Prevention of Uncontained Failure of the LPT Stage Disk
• ECTM N1 DEEC Event Record

Ignition Unit Replacement for MSP Operators

— Lanny Renshaw

When ordering a replacement ignition unit, make sure the one that the one removed has a Honeywell P/N stamped on the data tag such as 3070378-X, 3073914-X or 3061186-X, depending on engine model. The tag should be red. If the data tag is blue and the Honeywell P/N is not stamped on the data tag, this is an unacceptable core and you as the operator may be charged the outright price for the ignition unit. Also beware that if the engine is pre- SB 74-3003, which applies to classic engine models TFE731-2/3/4/5, you will need to order a pre-SB P/N (3070378-X) ignition unit which is a “sychronous” system where both igniters fire at the same time. Post-SB P/N (3073914-X) is an “asychronous” system where the igniters are fired independently of each other. MSP will not cover the upgrade to the post-SB 74-3003.

ECTM Kits P/N 831702-All for N1 DEEC

— Lanny Renshaw

Honeywell has issued a Service Information Letter (SIL), Ground Support Equipment No. 8, that asks operators to inspect the Serial Interface Converter for a lot number (M42754) which is known to contain possible wiring faults that may cause them to fail due to an overheating issue. If you find a converter with this lot number, contact a service center who can exchange it for you at no charge.

AD 2005-05-15, Prevention of Uncontained Failure of the LPT Stage Disk

— Lanny Renshaw

This AD became effective on April 18, 2005, and applies to the TFE731-2/2C & TFE731- 3/3A/3AR/3B/3BR/3R series engines. Initial inspection for the TFE731-2/2C engines with LPT stage one disk P/N 3072070-ALL or 3073013-ALL installed is at the next MPI or access to the LPT stage one nozzle, whichever comes first, not to exceed 2,200 hours. After the initial inspection, this AD must be complied with at every MPI but not to exceed 2,200 hours. If you comply with SB 72-3704, this will terminate the AD. For TFE731-3/3A/3AR/3R engines with LPT stage one disk P/N 3072351-ALL, 3073113-ALL or 3074103-ALL installed, complying with SB 72- 3705 at the next MPI or next access to the LPT stage one nozzle (not later than 12.31.2011) will terminate the AD. For TFE731-3B/3BR engines you must comply with this AD at the next MPI or access to the LPT stage one nozzle not later than 12.31.2011. You also must convert the engine to a TFE731-3C/3CR which will require the engine to go to a heavy service center.

ECTM N1 DEEC Event Record

— Lanny Renshaw

There are three things that will cause N1 DEEC to automatically record an event record.

1. DEEC transfers to manual mode.
2. An uncommanded engine shutdown.
3. A type two exceedance.

Also the crew has the capability of doing a “Pilot Initiated Event Record” by using the SPR/FUEL ENRICH switch (aircraft that are equipped with this switch) for that corresponding engine if the pilot observes abnormal engine operation. The event record is a five-minute scan, four minutes before the event, one minute after the event and every five seconds in slow scan. The event record also takes a 30-second scan, 20 seconds before the event, 10 seconds after the event and every tenth of a second in fast scan. The “Pilot Initiated Event Record” can only be used once between downloads. If the pilot initiates another event, it will record over the first one. To view the event records, go to the “View Engine Data” menu in your ECTM program. Then select engine S/N and go to “Event Record Display.”

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