Bell 407

[mike hunt]

We did read the book, and from what I remember that is what it told us to do. I do appreciate the tip for getting the engineers to regularly to check it anyways. The engineer on site left the chip in the logbook taped to the appropriate page for future reference.

[helidude]

What? You mean you don't have to send your finds to Jet Care Laboratories in New Jersey to analyze the metal so that the engine manufacturer can then decide for you if you're grounded or not, four days after you got a chip light??

 

Wow! what an interesting concept!

 

 

 

 

 

 

 

pssssssst!! Mr. Turbomeca, are you paying attention??

[DGP]

The 407 that I fly had 670 hrs on it when I started to fly and fix it...I noticed the metal on the lower plug about 2 mths later and of course you start to get concerned...do as the book says...never got a light on for almost a year which probably was 300-400 hrs later...but when the light finally came on it was ready to blow..just lucky..the #4 bearing is one of the biggest bearing in the engine...if it had been the #2 it would not have lasted that long...for sure

[helidude]

If that was an Arriel, you would be grounded as soon as you found metal on any plug regardless of a chip light or not.

[DGP]

As I mentioned after the bearing was replaced we flew the machine for about 1yr 6mths...started doing it again...we sent it away after 2mths of operation...we never got a chip light...same thing was happening with the #4 bearing...the lower chip plug will be the one picking up the metal from the #4 bearing...if you have the #2 going it will be on the top plug...more or less...use your own discression...follow the book...but I would be pulling the engine out of service sooner than later

[RTR]

What? You mean you don't have to send your finds to Jet Care Laboratories in New Jersey to analyze the metal so that the engine manufacturer can then decide for you if you're grounded or not, four days after you got a chip light??

 

Wow! what an interesting concept!

 

pssssssst!! Mr. Turbomeca, are you paying attention??

 

I often wonder how many here have actually read the process for dealing with metal found on a chip plug as published in the prospective M&M.

 

For the Arriel series engines turbomeca has a fairly detailed table of actions that must be carried out. Wiping off the plug and performing a ground run is not one of those actions. I don't think I have ever seen any engine manufacturer recommend just that for any metal contamination.

 

I think there is some confusion on what a pilot can do in regards to chip lights and or metal found on a plug. I know that inspecting and continuity checking of self-sealing chip detectors is listed as an elementary work task, but that is a far cry from performing the required maintenance action for a contaminated plug, and the inspection requirement is far and away from what a pilot is capable of doing.

 

Any time you find metal, through a light indication or a visual inspection of the plug, it will require some kind of maintenance action. Consult the applicable M&M. I guarantee you it will not say just clean plug and ground run. There will always be a more detailed inspection that must be performed.

 

Are you grounded? You better believe it. If you are a pilot, you need an engineer to carry out the required inspections and checks. If you are an Engineer you need to carry out those required inspections and checks.

 

This "run for 30 minutes and go" is an old wives tale perpetrated by the need/want/desire to get back in the air and back on the job. It is a dangerous practice.

 

Again, there is always a level of inspection/check required beyond clean and carry on.

 

Lastly the quoted post is patently wrong.

 

RTFM kids.

 

RTR

[SuddenStop]

the main thing I have learned over the years is to know your component and know its composition.

As well as knowing what particular fragments typically look like from individual items. You can identify fairly easy the item making the metal if you know these things. Is it a bearing? is it a gear? Following the schematics, And historic information you can also get a pretty good idea which item might be failing.

The sending a sample off for analysis is a required step in my eyes to verify what you believe. But as an engineer, you can determine if you're continuing to be grounded while awaiting those results, or going to keep it in service and monitor it. Thats always an option, but be aware of those consequences.

[helidude]

How many companies do you know actually ground their Astar while waiting for the laboratory results EVERY time they find ANY metal on any engine plugs?

[SuddenStop]

not many do. thats a fact

 

how many should based on the findings??? well....thats debateable LOL

[wrench spinner]

I often wonder how many here have actually read the process for dealing with metal found on a chip plug as published in the prospective M&M.

 

I guarantee you it will not say just clean plug and ground run. There will always be a more detailed inspection that must be performed.

 

This "run for 30 minutes and go" is an old wives tale perpetrated by the need/want/desire to get back in the air and back on the job. It is a dangerous practice.

 

Again, there is always a level of inspection/check required beyond clean and carry on.

 

Lastly the quoted post is patently wrong.

 

RTFM kids.

 

RTR

 

For the C20, cleaning the plugs, and doing a 30 minute ground run is exactly what their MM calls for. If it is paste, less than 4 slivers, or below a certain size. Further action is only required if additional chips are found during the 30 minute run. To advise that this is strictly an old wives tale may cause pilots to doubt their engineers even when they ARE following the MM.C20B-ChipLights.pdf