Aural Warning on Eurocopter EC120

[JTobias]

All,

Long time, no post but here I am.

Are any of you aware of an audible warning tone that is heard on the Eurocopter EC120B without an associated illuminated caption, on the Caution Warning Panel (CWP)?

On two recent flights, I've heard the warning tone, with no light on the CWP. Initially the tone was a single 'bong' and then this was repeated a short time later. This was later followed by a double 'bong'. When I landed I noticed that there was oil over my tail boom and fenestron. My engine oil level was also much lower than the minimum level.

I had a similar experience today whereby I heard two separate instances of the (single) warning tone followed a short time later by a double 'bong'. Immediately afterwards the Engine Oil pressure light illuminated and upon landing it was again evident that I had run out of engine oil.

Note: this trip was after visiting maintenance and it had been determined that the oil was escaping through the breather tube and it was almost certainly a seal that needed replacing, which has been ordered. I am/was therefore fully aware that I was losing oil slowly.

The point to the question is basically whether or not these audible tones without an illuminated caption (single and double) are designed to be an early indicator of an imminent 'failure' of something.

[GoodGrief]

My engine oil level was also much lower than the minimum level.

Immediately afterwards the Engine Oil pressure light illuminated and upon landing it was again evident that I had run out of engine oil.
Note: this trip was after visiting maintenance and it had been determined that the oil was escaping through the breather tube and it was almost certainly a seal that needed replacing, which has been ordered. I am/was therefore fully aware that I was losing oil slowly.See me in my office at 10am. Bring your license and a book of matches...:ugh:

[puntosaurus]

Well I think you can safely say, from your own experience, that the answer is Yes !

What was the oil pressure gauge reading whilst all this was happening ?

[jeepys]

This is going to be fun!

I am sure there must be another twist to the tale and not as clear cut as JT suggests as after all if you know your engine is going to lose oil you don't fly

[JTobias]

FFS - maybe this is why I haven't posted for a while...........

Whilst it may seem obvious what the aural notifications may or may not have been, I want to know if its fact and if so where does it state it. Two engineers that I have spoken to and a number of EC120 pilots aren't aware of any aural indication without an associated caption and so if it is an early indicator, what is it an early indication of?

What's the parameters that cause a single notification versus a double 'bong' ?

Does it give an indication of any failure or is it specifically for the main engine oil ?

If it's an indication of a failure of anything then what point does it serve if it doesn't give you an idea of what the failure might be?

The aural warning on its own therefore doesn't actually tell you anything unless it's only evident in one type of malfunction...........

To answer one of the other questions, no there were no other indicators , all T's and P's were in the normal ranges and my engineer had cleared the aircraft to fly subject to certain parameters which were maintained.

[puntosaurus]

What do airbus/turbomeca have to say about your experiences ?

[garly1]

It's hard to read this thread without shaking your head, I have no idea regarding the audible warnings but to fly it again was a silly idea! Just what parameters did your engineer stipulate? Surely these parameters didn't allow you to fly to the point that you landed without any engine oil?

[ascj]

I think it goes,
Bong
Bong-bong
Bong bong bang!


Don't quote me on that

[Efirmovich]

Yes I had a similar situation.
Straight and level flight, and one gong, looked down at the panel and no warnings, all T+P's ok,, then another, again no caption, so I thought the gong was playing up but started to look for a LZ. On the third gong and monitoring, I just saw the MRG caption light, glow very briefly then it started more regularly with the light during the auto and Pan calls !!!


Note, its important to turn the Gong off when you have established the fault as it overpowers the RT with ATC.


This was years ago before EC had decided to glue the rubber bung into the back of the output shaft, landed and the whole contents of the MRG were over the tail !
In my opinion the caption should remain illuminated for at least 5sec following an event as in my case the oil press was just dipping below the minimum for a split second enough to trigger the audio warning but not long enough to put the light on.


E.

[John R81]

I think Efirmovich has the answer.


Oil content reducing, and momentarily the pump fails to maintain oil pressure above the minimum. Caption & Bong are triggered, but as the "dip" below minimum was momentary the light is extinguished and by the time you look down - hence no caption; the system is "reset" to normal conditions. Later, this happens again.


Being myself a coward in the RH seat, my personally imposed rules for flight include "you bong, I land". With a caption, that would be immediately / as soon as possible / and theoretically "as soon as practicable" per the flight manual (though unless it is something I fully understand - I had a generator failure, for example - you will find me in a field - see above) then unless . Without the caption, I opt for "as soon as possible". I figure that working things out / chatting with an engineer on the phone whilst standing next to the machine is my personal risk-limit.

[rottenjohn]

Maybe want to go back to who ever did your type rating. Gong will sound when a red light illuminates on the cwp.Whether momentarily or not, for example it's not unusual for the mgb pressure light to come on in bad turbulence along with the associated "gong".
And the pilot who did the auto and pan pan call when the mgb pressure light came might want to read the pom.

[ersa]

Rottenjohn is right.....

Ive spoken to our old engineer, if getting Gong's in flight but no warnings on the VEMD/CWP , could be water in the system.

But if you get Gong's in flight , almost 99% a red warning would of appeared on the VEMD/CWP

If you lost the oil from the engine, there would be low pressure Gong / High Temperature Gong going off.

The Ec120 is a very good machine, you do get the odd gremlin from time to time (generally electrical)

The fact you landed (I assume ASAP) whats the problem ?, unless you continued on after the audible gong's went off could be an issue

Its hard to give a definitive answer, with all the posts above mine, you have a general idea now

[BOBAKAT]

The gong is when you use too much power...exceed the power available...

[500e]

Are you all flying the same machines :confused:

[Efirmovich]

Maybe want to go back to who ever did your type rating. Gong will sound when a red light illuminates on the cwp.Whether momentarily or not, for example it's not unusual for the mgb pressure light to come on in bad turbulence along with the associated "gong".
And the pilot who did the auto and pan pan call when the mgb pressure light came might want to read the pom.


RJ


As I am fully aware of what the ROM says, however as I was directly over a military base and talking with them plus I pay for my own transmission I decided that was the best course of action !:ugh:

[JTobias]

Thanks for all the replies, I'm not certain if we've actually obtained a definitive answer though. It would appear that the aural tones can be single and/or double but with no associated caption on the panel, possibly indicating that something isn't right but not pointing to anything in particular - until a caption illuminates. I'm fairly certain that there was no 'momentary' illumination of anything because after the first one I was monitoring the panel like a hawk and I experienced the double bong without anything on the CWP.

The VEMD in particular is not perfect as anyone who flies with them will know and therefore there's every possibility that the aural tones could also be "buggy", although in my case they were clearly suggesting a problem with the engine oil. I may contact Eurocopter/Turbomeca to see if there is a method behind their single/dual bong scenario.

By the way my usual response to anything unusual (aural tone/caption illuminating) is to land, but I've had many discussions with instructors and examiners over the years and that's not always practica.l particularly if you're over water!! I am regularly getting the General Parameter Exceeded warning on my VEMD and last week I had the dreaded "OVER LIMIT DETECTED" which threw me into a total panic only for me to be told that the VEMD "sometimes does that" and you can ignore it. The technology in that equipment is now 15+ years old and the software too. There is more capability in my Apple iWatch these days.


Joel

[puntosaurus]

No question this is one for the manufacturers. You might even want to MOR it, just to put a bit of energy into getting this resolved.

To my possibly naive way of thinking, the aural warnings relating to CWP captions are exactly that, an attention getter that an important CWP light has come on. They're not some sort of generic advance warning of unspecified impending problems.

Either way, the way it ACTUALLY works should be in the RFM.

[JTobias]

Puntosaurus, I agree - there is no point in having a warning tone that doesn't indicate what the warning actually is. I'll drop a line to Eurocopter/Turbomeca.

[puntosaurus]

Up to you of course, but see below.

REGULATIONS
COMMISSION IMPLEMENTING REGULATION (EU) 2015/1018
of 29 June 2015
laying down a list classifying occurrences in civil aviation to be mandatorily reported according to
Regulation (EU) No 376/2014 of the European Parliament and of the Council

2. TECHNICAL OCCURRENCES
2.1. Structure and systems
(6) Malfunction or defect of any indication system when this results in misleading indications to the crew.

Here (http://www.aviationreporting.eu/ReportDetails.aspx?occsrc=1&countrycode=GB) is the place to make the report.

[500e]

TJobias (http://www.pprune.org/members/168323-jtobias)
Said
"Thanks for all the replies, I'm not certain if we've actually obtained a definitive answer though. It would appear that the aural tones can be single and/or double but with no associated caption on the panel, possibly indicating that something isn't right but not pointing to anything in particular - until a caption illuminates."

This is the point I was making people having no or incorrect understanding of the machines they are using , technology is great but if you don't understand it it can be fatal
If the OEM has not made it clear the regulators should have by now, this is how 30 min run dry problems started.
Surely a definitive answer is exactly that .
I am not saying you do not make a value judgment taking in circumstances.
puntosaurus :ok:

[nellycopter]

Mmmmm that bong is the least of your problems ....
you need to prepare yourself for some stress matey....
as I was told just before I bought my 120...... they are a great machine but just hope and prey you never have to deal with TM...... sure enough after six years of enjoying every min of my aircraft the time came when I had to replace the engine ( mine stared making metal) from there I think I could write a book ...... very long two year story cut short.... 4 engines in two years.... believe it or not the first one they gave me as a service exchange engine had a fault that it had been removed from THREE other aircraft around the world for ... and yet put back into service each time ... next one fell to bits inside, last one was the straw that broke the camels back and the sad time came to get rid of the aircraft .... in short TM forced me out of my lovely 120... I just couldn't do with stress and hassle anymore talk about take the P*** ..... I hear from the new owner that they are still now having some problems with the latest engine .... so I wish you luck , you really are going to need a bucket load of it ......
.......

[Rigidhead]

J Tobias,

The "parameter out of range" will show up on shut down as you do have parameters out of range when the aircraft is not running.
Regarding Overlimit warnings, they should not be ignored. Go to the overlimit page to find which parameter is showing as being exceeded. There have been some false Nr over limits that are the result of a failed resistor, but these are usually showing a very high (480 to 490 Nr) when never being in an autorotation on that flight. On the other hand, an Nr exceedance of 445 or so during a steep turn or flare during an auto practice should of course not be discounted.
The VEMD may be getting to be older technology, but it was and is miles ahead of what came before it in terms of presentation of information and taking the "maybe" out of exceedances and the maintenance required because of them.

(I freely admit a bias towards the aircraft)

Regards,
Rigidhead

[JTobias]

Thanks Rigidhead,

I have checked the over-limit page and the parameters are all Zero and my maintenance company have advised that this will be a spurious reading which can be ignored.

Joel