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-   -   EC135 (https://www.pprune.org/rotorheads/189945-ec135.html)

Tango and Cash 9th May 2009 19:29

My understanding is that the VEMD in the EC135 functions slightly differently than the VEMD in the AS350. Probably has to do with German airframe and French electronics, some things got lost in translation. :}

Brilliant Stuff 9th May 2009 21:11

Well in our CPDS machine from 2002 we do not get any fuel management apart from the gauge for the three tanks. Which is within 4%-6% accurate as it says in the manual. But maybe the current machines are more accurate or have more standard options.

RVDT 9th May 2009 22:29

3top,

I assumed that you may have flown a helicopter before but maybe your watch no longer works. Do you keep a log of your fuel flow/consumption based on past history?

Trusting the gizmos implicitly is probably not so wise in any respect.

Study the available tech data you have and work out what is "wrong" with the fuel system. (Read between the lines).

Get back to me when you have worked it out.

BTW MEGHAS and CPDS are not related. A B3 or a 120 are pretty simple compared to a 135.

victor papa 10th May 2009 14:44

It is simple. The b3 and/or 120 has 1 tank which serves as the storage and feeder tank. This means the VEMD display only has one transmitter telling it the fuel available for the whole system and then as you said before the DECU tells the VEMD how much it is using vs the airflow available and power setting. Simple sum for the VEMD and accordingly you get on the B3/Ec130/120 time remaining on current fuel. The 135 has more than 1 tank per engine and the "storage tanks do not feed their info to the vEMD. The result is that the vEMD still gets from the DECU how much fuel is used, but it does not know how much fuel in the system so 1 halve of the sum is gone.

3top 10th May 2009 16:41

Okay guys,

that's all good.
What I don't get, is that EC wants to charge extra, what I would call an essential item, considering the rest of the equipment.
I would certainly assume that it should be a standard/basic feature on a full-blown IFR-MEGHAS ship. Maybe on an old VFR ship you sell this as a "useful" add-on, but on a glass-cockpit-IFR ship - it should be included....

Anyway, based on the answers given, I understand there is no way to look at the panel and get a direct info on "flow + time remaining", without having to calculate - so the fuel management option will be added! (And again, it is a "no-weight option" - just software, extra charge....)

RVDT!

YOU assumed right! I have a few hours rotor time (11.5K and counting)
I know what you get at, and you certainly right!

Just as a basis for discussion, here is what I did in the past/present:

ALL VFR in mostly hostile terrain.
My first two jobs, I did not have a fuel gauge! Everything done by watch!
Of course it is possible to do it by fuel level and watch alone, but:

At my present job (long lining in a mining project) you would have an extremly hard time to do the watch thing, due to the ever changing weights you fly. Flying time with the same fuel load can vary as much as 30 min (50% fuel load).

Fuel gauges are regularly checked/calibrated (tanks drained and refilled by the gallon to check low fuel light and quantity indication).
So they are actually VERY acurate!

I got very appreciative of the "time remaining" feature on the 350 VEMD (by the way in the EC120 you have to pay extra for this too).
It is extremly helpful to know that under pick-up load time remaining may show 27 min to "zero fuel", however once under way power required drops and I will get some 7-9 min back (35 min) - indicated on the VEMD (no need to guess fuel flow and calculate).

One of the missions for this ship(EC135) will be SAR, medevac - over generally hostile terrain. Although we certainly will not plunge into this from zero, we expect to work up to night and IFR missions fairly quickly.

As it is, the EC135 seems to be a rather heavy ship already and fuel will be a limiting factor. Being able to get a few more minutes, based on exact data available may be crucial someday.

But don't worry RVDT, if I ever get close to my empirical flight times on the same fuel load and the gauges/indicators didn't change - I'll be on the ground before the big silence screams at me!

Thanks for all your inputs!

Is there anything else I should consider? experiences? suggestions?

Tomorrow (Monday) is the last round with EC to freeze the order spec sheet ....


Cheers,

3top :cool:

southerncanuck 10th May 2009 16:44

sir, for your SAR mssions, will you be using searchlight or flir camera? if so, do you need mounts?

3top 10th May 2009 21:18

If SAR becomes a need, this will be only a daylight affair for a long time to come...

why? you got mounts to spare?


3top

southerncanuck 11th May 2009 15:58

yes we do, easa and faa stc'd
send a pm, will reply with all the data
cd

Geoffersincornwall 29th Jun 2009 13:44

EC135 Certification Limits
 
Can somebody settle an argument for me and confirm that the EC 135 is certified to +45 degrees C.

RVDT 29th Jun 2009 14:02

RFM Section 2 Page 5 -


Maximum air temperature is .......................ISA+39C (max +50C)
With the proviso if you have MEGHAS (Glass cockpit) ground or hover is limited to 30 minutes with OAT ≥40C.

EASA Approved Rev. 14 P2 CPDS

Phoinix 29th Jun 2009 14:03

FLM:

2.10.1 Ambient air temperature limitations

Minimum air temperature is -35°C
Maximum air temperature is ISA+39°C
(max. +50°C)

Geoffersincornwall 29th Jun 2009 15:11

RVDT
 
Thanks, I assume that was a typo and you meant ISA +35

G. :ok:

RVDT 29th Jun 2009 15:24

Geoff,

No typo it is at it says - meaning I assume you can operate up to ISA +39 not to exceed +50.

ISA +39 at sea level would be ~54 but at ~2000' it wouldn't.

Geoffersincornwall 29th Jun 2009 16:27

Temp lmits
 
Not being a 135 man I'm not sure of the implications of the 'glass-cockpit' side of things. Are these aircraft in the majority or minority and what sort of intrumentation do you have if no glass cockpit. Is it back to analogue dials and basic DH/HSI ? What if you need an IFR capability with 2 pilots?

G.

What Limits 29th Jun 2009 17:32

Although the T2/P2 option is now the weapon of choice, I believe that it is still possible to choose between the traditional 'analogue' style intruments (CDS version) or the 'digital' style (CPDS). IFR and two-pilot intrumentation is also an option for both.

I would imagine that most are of the CPDS style although a few T1 CDS linger.

skadi 29th Jun 2009 18:59


Although the T2/P2 option is now the weapon of choice, I believe that it is still possible to choose between the traditional 'analogue' style intruments (CDS version) or the 'digital' style (CPDS). IFR and two-pilot intrumentation is also an option for both.

I would imagine that most are of the CPDS style although a few T1 CDS linger.
The CPDS is not the same as "glasscockpit", just the engine instruments are "digital style, while in the CDS they are traditional. The actual machines are sold only with CPDS as standard, but you can choose between analog or digital ( "TV screens" ) flight instruments.
The reason for the temp limits with glasscockpit is, that these screens produce a lot of heat and with high OAT may come offline.

skadi

RVDT 29th Jun 2009 20:18

And so I am told, (without looking it up) the "steam" instruments are heavier.

Appreciate there are about 15 flavours of EC135.

I was also told "never again!"

The MEGHAS (which is now probably the norm) does generate a lot of heat. Add Garmin GPS, FM's etc etc...................................

Death on a hot day!

Appreciate also that the operation/installation or not of the A/C is not within the certification criteria.

We have 9 displays.

Helinut 29th Jun 2009 20:42

The boys and girls using the EC135 in the Middle East will have much better information than me, but all that glass cockpitry is a bit sensitive to high temperature. Flying for the police in the UK we occasionally get a warmish day and if the aircraft is left out on the pad it can cause problems. Various units use portable radiation shields in the cab to reduce the heat soaked into the instrument panel, which seems to help.

Generally, the glass cockpit is pretty reliable but it does play up when it gets hot. EC have setup the vent system so that it diverts the air to the instrument panel rather than the crew, so they obviously are aware of the issue. I don't have an FM to check but I recall the whole issue starts at 30 C.

vortexadminman 29th Jun 2009 22:49

Sadly nothing will pass muster with the bean counters. However in this never ending saga of 135 vs 902 for police/HEMS go and ask ALL off them what their (the user or customers) view is. Am sure all of them will say their machine is best................ then ask the ones who have used both.... or more. I prefer 902 as it is a stable. non shaky platform blah blah blah . But yes I am biased.

Phoinix 6th Jul 2009 10:37

Any information on Switzerland 635's that were grounded lately?

Phoinix 22nd Sep 2009 15:34

Can someone tell me where to find information on "VEH PARAM OVERLIMIT" displayed after shutdown on CAD's lower edge.

Phoinix 22nd Sep 2009 16:23

I cought something while doing type rating, that TOT is still high after shutdown so you are more careful during next start. The message normaly goes away until the next startup, but I want to know what exactly it is.

MightyGem 22nd Sep 2009 19:26


Can someone tell me where to find information on "VEH PARAM OVERLIMIT" displayed after shutdown on CAD's lower edge.
Yep, we get it after every flight, and ignore it. I think it's because the generator out goes out of limits for a few seconds during the start(but I could be wrong!).

handysnaks 22nd Sep 2009 20:40

MG, I think the warning may be down to an MMI issue as the nr slows down rather than a genny.

eagle 86 23rd Sep 2009 01:30

Engine T's & Pressures. Note the red lines.
GAGS
E86

zorab64 23rd Sep 2009 13:51

Phoinix - suggest you put VEMDs into maintenance mode and scroll around for the failure code. We get it regularly and, like MightyGem, give it a good ignoring.

When we first got the aircraft, we looked into every similar issue until we realised that they were invariably code 103 or similar, all occurring at 00:00secs - i.e. probably some small electrical hiccup with no likelyhood of it having occurred in flight or anything to do with handling errors.

Unfortunately, our experience has led us to follow the ignoring procedure above and ECD/TM (don't know whether it happens with P&W) have not addressed what appears to be a CAD/VEMD/FADEC electrical sensitivity issue to remove these "cry wolf" CAD warnings - one day it might be important/relevant, but we're unlikely to find it until the engineers download FADEC data. Only time we check it out is when we feel we might have mis-handled, which is hardly ever, of course!! :ok:

Phoinix 24th Sep 2009 07:07

Eddie, i understand your concern, but... Can you help me find a standard procedure for this indication? I might be blind for not finding it in flm or training manual.

victor papa 24th Sep 2009 08:22

Eddie1, my understanding is that the engine manufacturer will not be concerned as the VEH parameter indicate that it is caused by the airframe and not engine. If it is not electrical system related check the pitot static lines and temp probes. Had it a few times that it is caused by the VEMD not thinking that the PO and outside T can be for the same place and then records it as a VEH parameter out of range.

FloaterNorthWest 24th Sep 2009 09:09

We have a similar problem in the A109 Grand where the aircraft throws up MAINTENANCE on start due to an electrical disturbance during the normal start procedure.

In the age of software driven aircraft surely these glitches can be written out?

skadi 24th Sep 2009 09:28


@eddie1
If the warning illuminates at start up because of to high amp loads from the Generator is one thing. This indication goes off after startup.

But thats a different message : GEN PARAM OVERLIMIT

skadi

eagle 86 25th Sep 2009 07:27

At the risk of repeating myself - check my previous post (581) - on shutdown the engine and transmission oil pressures drop to zero - the VEMD detects this and sends the message - it is logical and normal - note the red lines under the pressure strips! Please don't ignore something you don't understand particularly in a helicopter as complex as the EC135!
GAGS
E86

Phoinix 26th Sep 2009 10:50

Well, finnaly I got an explanation from Ec guys. VEH PARAM OVERLIMIT is suppose to be a message warning the crew, that one of the parameters has been in the caution area - in our case MM was in yellow at one time not exceeding 7,5'' (manitenance acknowledged) - and so you don't have the safety factor of reaching that level of exceedence once again without manitenance action taken - expensive.

Funny that EC manuals don't say much about it.

skadi 26th Sep 2009 17:07

So in this case, there should have been an postflight entry in the maintenance page, section overlimits ( VEMD ) for this Flight-Nr.?

Nice to get this info finally

skadi

Phoinix 26th Sep 2009 17:24

Yes, the entry was done some time ago, but went past me.

skadi 28th Sep 2009 19:29

I went a little bit deeper into the maintenance staff. If VEH PARAM OVERLIMIT shows up in the flight report after shut down, you should switch the CPDS into maintenance mode, select FAILURES and then the approbiate FlightNr ( normaly the last one ) with the +/- Buttons. Push ENTER and you get numbers of failures for the CAD and the VEMD. Select the one with at least 1 failure, press ENTER and you get the Failure Diagnosis. The first line shows the time of the occurence and below the respective failure code. There are some more than 100 different codes in the technical manuals ( SDS System Description Section 31-65-00-9 ).
One common failurecode is 109R, which indicates a failed selftest of the MMI, but if the MMI is indicating normal, this failure could be ignored. Its caused by the selftests ( During startup of the CPDS ) of the two VEMD Lines and when the analysis of Line 1 finishes earlier than the analysis of Line 2, the VEMD deactivates the results of line 2 and the errorcode 109R may be stored in the system.

skadi

RotorDompteur 29th Sep 2009 05:50


Can someone tell me where to find information on "VEH PARAM OVERLIMIT" displayed after shutdown on CAD's lower edge.
A number of different explanations has already been offered, but I think you really have to distinguish between the various messages.

When the "VEH PARAM OVERLIMIT" is displayed on the top VEMD screen it is due to the fact that the Flight Report occupies the lower VEMD screen.

Think about it;
The situation is right after engine shut down.
Right before the Flight Report appears you have engine oil pressure low and red underlines flashing on the lower VEMD screen.
When the Flight Report appears on the lower screen this information cannot be shown anywhere.
So what the "VEH PARAM OVERLIMIT" is telling you is that some parameters are presently out of limit , that is engine and MGB oil pressure low.
The idea of the system is that you should always get an indication that there is something wrong.

The same would happen if you are shown the System Status page while having low oil pressure.

In fact, try this; next time when you are done with the Flight Report press Reset to remove it. Then press Scroll to see the System status and "VEH PARAM OVERLIMIT" will pop up again.



If you on the other hand are shown “OVER LIMIT DETECTED” or “FAILURE DETECTED” it is another story and you should consult the maintenance page for details.


RD

skadi 29th Sep 2009 07:49


When the "VEH PARAM OVERLIMIT" is displayed on the top VEMD screen it is due to the fact that the Flight Report occupies the lower VEMD screen.

RD, thats it. Thank you.
I just switched the battery on and switched off the lower screen.
VEH PARAM OVERLIMIT went on!

skadi

helipeek 30th Sep 2009 09:44

Compressor Wash EC135 P2
 
I need to do a comp wash on an EC135 P2+. But can't seem to get hold of the procedure from anyone.

Can anyone out there help please?

Either point me in the right direction or tell me what the procs. are.

many thanks

helipeek:confused: (Vainly pushing buttons hoping the bonging noise will stop!!)

Marco 30th Sep 2009 09:54

Get in touch with your engine manufacturer, Pratt & Whitney presumably?

What Limits 30th Sep 2009 13:34

Or ECUK if that is where you are.


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