MRG Chip lights

[bambybucket]

If you get one in flight you land ASAP but assuming that you have to fly for a peroid of time to get to a suitable landing area, do you maintain the power setting or reduce air speed (and therefore power) to BROC speed to try and reduce the load on a posible failing gearbox. I favor the last but I have also been told that any change in power after the indication, can increase the chance of a failure. Any thoughts please.

[BigMike]

Had this happen a few months back while over water in a 206. I reduced power and brought my speed back to about 65 kts, decended to 100 asl, and armed the floats. Checked the MRG gauges, no temp increase or falling oil pressure. Landed in a clearing just after I crossed the beach. Shut down and pulled the plug. Alot of metal. Couldn't quite read the part number on one peice. Overhaul latter found it was a mast bearing if I remember right.

Wasn't there a Puma ditched in the North Sea a long time ago when a MRG chip light came on?

Cheers BigMike

[NorthSeaTiger]

A 330 or 332 ?, I think there may have been a S61.

[outhouse]

Yes a S 61 went down a few years ago into the North Sea, big chunk missing from the combiner gear in the main gear box. As I remember a complete tooth came off the gear wheel and went down between the combiner and the free wheel output gear. Very very nasty!!! I think the chunk may have been to big to reach the chip detector though.
Outhouse.
:ok:

[Thomas coupling]

Presumably it is essential that you have to continue flt with a MRGB chip light?
Big Mike got it right in one if you ask me.

Isn't this what captaincy is all about? Risk management.

[Oogle]

Many flight manuals will have this put down as a "land as soon as possible" which means do not overfly a suitable area.

The more prevalent one is the "MGB Oil pressure" which, in most (if not all) flight manuals is a "land immediately".

That being said, as Thomas Coupling mentioned, this is why we are paid the big bucks :rolleyes: - to make these decisions.

Loss of oil pressure will invariably lead to the chip light.

(End of lesson)

I think Big Mike has got the bull by the horns in his summary. Good decision!

And please. Don't anyone bring up the old saying - "What if it is an electrical fault that just happens to bring the light on?"

[Aser]

I would do exactly what BigMike has done.
It's something I have been thinking about sometimes and I came to the same "procedure" in my thoughts...
As if I lost one of the two Hyd. sys. over water

I don't know if reducing power increases or not the risk of the failure but the manual says "reduce power", and I find it very logical.

Regards.

[SilsoeSid]

OogleLoss of oil pressure will invariably lead to the chip light. I would have thought it would bring on the MGBP light!!!

:confused:
SS

[Oogle]

Sid

You are right but I "ASSUMED" the reason you knew you had a loss of oil pressure in the first place is because the bloody MGBP light was on already!

Mental note:

"Be more careful when writing on Pprune for fear of :ouch:

[212man]

I think it is a little simplistic to say that loss of oil will lead to a chip light as a normal consequence. If you lose all your MGB oil and continue to fly to the point you start getting chip lights, you probably have gone past the PNR and won't have much time thereafter to dwell on the topic; the MGB is now in it's final death throes! On the other hand, it is quite common to get chip lights with no other associated indications and, as long as there are no further indications, generally FLM advice is to land as soon as possible (as opposed to immediately).

[offshoreigor]

Hi All

If you have a MGB Chip, follow the CL.

If you have secondary indications, ie. Hi temp, Low Oil pressure, Land/Ditch Immediately!

A dry MGB on any type is not good news. Whether you fly an R22 or an S61 this is not good.

I know a guy who flew a 212 to a container ship with all of the above and was lucky to land. He said in the future after seeing the damage, he would ditch.

An S76 recently had a chip followed by Hi Temp+ Low (0) oil pressure and flew about 50 miles and landed safely. The damage to the MGB was catastrophic.

So use your own judgement. Me, I would ditch with a secondary indication.

Cheers,

:eek: OffshoreIgor :eek: