RJ100/ALF507 Soft Fault

[plhought]

Howdy,

Newish Avro operator, with previous experience on the 146. Hoping some European experts with a little more experience with these engines can shed some light.

We seem to be constantly getting the ARINC429 Soft-Fault (Code '4' in the window) across all four engines. ECU has been changed on #3 for troubleshooting, with engine harness checked (Don't have the manual in front of me but can get you harness number if required). Still same behaviour.

Reset FADEC fault and do a run - still no change. Code 4 shows up.


In addition, crews some-time complain of the autothrottle not reaching the N1 target. When it does occur it's around +/- 1.5% of the target N1. Related to above?

Is it something to be concerned with? Is this a typical soft fault on these aircraft? Should we be looking somewhere else like the DFGC's or airframe wiring?

Cheers!

[fixaBAe146]

Hi,

If I remember well the codes 4 and 8 are always alternating on the fadec when the engine is not running this is normal. Soft faults on the soft fault indicator are normally just reset, can be misleading. Remember it's a old simple system. In respect to the N1 shortcoming, is it always the same engine? If yes check if the resistor is not open circuit and you have normal indication in the cockpit, amm gives you a list of the resistance for each dash number. Cockpit indication should not be 0. Hope this helps, otherwise I come over and give you guys OJT on the RJ'S, always available as contractor. ;-)

[fixaBAe146]

The only thing you need to worry about is the codes that are between 4 and 8 those are the real fault codes.

[plhought]

Cheers for the info!

Pretty much what I figured. Knew Code 8 was the standard display check, but just wanted to clarify with Code 4. Thanks again for the heads up!

The N1 shortcoming was reported as across all four, although it hasn't been reported for a good few weeks now. It was snagged along with a bleed hogging issue that we dealt with that evening, and couldn't fault the AT or FADEC during the requisite engine runs.

Once again cheers for the help!

[hvdkelen]

Hi,

If you join Queen of the Skies - BAe/Avro 146RJ Appreciation Group on FB, you'll find a lot of knowledgable RJ/146 engineers willing to help.

[plhought]

Thanks for the reply.

Took a peek at that Facebook group. Some great stuff on there!

[Fly_high_club]

Hi
I was wondering if anybody can send me a customized version of MEL

[Engineer_aus]

It has been a while since I worked on the RJ100, however if I remember correctly the TMS actuator or down that part of the engine can be faulty.

[plhought]

No TMS actuators on the 507-1Fs...

All done in the FADEC.

[aryo barghi]

[QUOTE=Fly_high_club;9405518]Hi
I was wondering if anybody can send me a RJ MEL. i have FAA one but i do need uk Version