As it is a maintenance procedure, i.e it is in the maintenance manual, you may want to contact your maintainer!

PWC 71-00-00 POWER PLANT - CLEANING

ECD 71-65-00 7-1 Cleaning Engine Compressor

Depending on the aircraft it may involve removal and blanking of the bleed air lines. Some A/C have optional quick disconnect bleed lines. Reason being that you do not want compressor wash goop in the BA heater and subsequently in the cabin.

Read up on PWC's policy with the difference between desalination rinse and performance recovery wash. They recommend a recovery wash only if it needs it as determined by power check / trend.

EC135 Fuel Tank
 

Can anyone tell me where the fuel tanks are located in an EC135.

it looks as if they're under the floor as in a Huey, but maybe someone can correct me.

Under the floor is absolutely correct.

Thanks What Limits.

Any idea of how far they extend ?

We're trying to mount a spectrometer on the floor (approx 1 meter X 80cms) in the cabin, but looking through fuel will interfere with the operation of the instrument.

Do you have any references to documents that show the location of the tanks ?

The two-piece bladder tank sits between frames 3 & 5. Frame 3 is about 1.5 ft behind the forward landing gear fitting, with frame 5 located at the rear landing gear fitting.

I/C

And then you have the 2 SUPPLY tanks after that which extend pretty much to the rear of the boot floor.

RFM Section 7 Manufacturers Data.

If your spectro is upset by the fuel system you probably won't be putting it inside a 135.

Thanks to all.

Doesn't having the fuel spread over such a large area play merry hell with the CG as it burns off. ?

Maybe this helps you to understand how it works:

http://img85.imageshack.us/img85/1775/135tank01.jpg

http://img30.imageshack.us/img30/3640/135tank02.jpg

Thanks Eivissa A picture is worth a thousand words !

(It took words to say that though):}

What about mounting the spectrometer below the fuel tank ?

I'm thinking along the lines of the "Mission Pod" as fitted to Police aircraft,
designed and fitted by McAlpines ( Now ECUK ) at Oxford -
they might be able to come up with a variation of this that might do the job,
although you may also need to factor in the cost of converting to High skids ?

http://i34.photobucket.com/albums/d1...MissionPod.jpg

http://i34.photobucket.com/albums/d1.../Coconutty.jpg

I saw the latest revision to the FLM (6.3) and I got to new Supplement 9.2-86 Night vision imaging systems / NVG.

Effectivity: observe FMA 11-24 with annex.

What is FMA 11-24 and where can I read it?

Which EC135?
 

Hi

If a company wanting to do a charter flights around Europe want to buy EC135 VIP should we buy the with PW or Arrius?

Any ideas how not to make bad decision?

Depends on the colour of your tail. P&W will smoke it up real nice very soon.

P&W - Very reliable, and comparatively economical, but also :

Some people use Airglaze to make it easier to keep the tail clean.

Turbomeccas respond faster compared to the P&W I am told.

I am also told the P&W are less fussy.

I think it's customer service what has people jumping ship to P&W.

TM engines start faster & more traditionally (TOT up to 750 ish), P&W take ages before the TOT starts to register and you wonder if they've actually lit up, as it's so benign - but they all get there in the end.

As has been said, TMs much cleaner than the P&Ws.

The biggest difference (certainly with TM's power by the hour (PBH) or P&W's equivalent Eagle programme) is that you own your P&Ws. It means that when one is removed for unexpected maintenance, you'll get a loaner, which you're then obliged to swap back for your "own" engine when they've fixed the problem, almost as soon as you've got it back, or you'll pay. TM will just replace your engine (the old one goes back into the pool when it's fixed) - so one change rather than two. For some, this may be good news (as you know how you've looked after your own engines), for others it could be more annoying - certainly if they're fitted in a 902! (yes, I know we're looking at a 135!)

P&W require a daily rinse, TMs every 20 hours, unless when operating in saline environment (recently re-defined), when it's daily. You can do a hot or cold rinse with TMs, cold only for P&W.

On a daily basis, it's a lot easier to put oil in the TM, as you can do it standing on the skid - you need to be more of an acrobat to get it into the P&W, as you're almost hanging off the blades!

We've had TMs for 6 years, 6500 hrs - fantasically reliable, start together straight away every time (with 40 AH battery). PBH, admitedly, but never had a spares problem and only shut one down once, in that time (oil loss due to bearing seal failure). Don't notice any difference in power available betwen the two.

If it were my choice, I'd go for TMs again as they're so much cleaner; start faster & more obviously; & are easier to top-up oil. Pilot's viewpoint, mind, not engineers - they might see it differently?! :ok:

EDIT to explain Coconutty's humour: if you're not familiar with British children's shows in Prague, take a look at The Sooty Show | The Official Sooty Website | Home of Sooty, Sweep and Soo! ;)

A question for all gurus out there:

H-V charts in the FLM are for Single Engine Failure, so OEI flight regime, right?
Certain emergency procedures, like T/R failure bring us to a point where we need to (in some situations) roll both twist grips off and perform autorotation.

OK, we got that covered in the FLM also (autorotation). But, OGE hover T/R failure or IGE for that matter: how do we know at what height can we roll off the throttle, gain speed and land.

Do these maneuvers have to be proven for certification? If so, why there is no normal (all engine fail) H-V chart?

There is no dual engine HV chart in any twin engine helicopter I'm aware of. The reason is that the engines have enough isolation that no single failure should be able to take both engines out at the same time.
And if there was a dual engine HV chart, you wouldn't want to know how large it would be...
A benefit of having two engines.

Well I think that if both engine fail on EC135, the will autorotate as any other helicopter with similar rotor and weight. So I think the HV chart would be similar to any other heli.

Just my opinion of helicopter newbie.

ILblog, its not that simple as I'm sure you'll soon learn. Autorotational capabilities depend on rotor (disc loading, rotor inertia, rotor solidity,...), weight and some other fuselage-rotor interactions and mostly all types of helicopters have different autorotational capabilities, that also vary with atmospheric conditions.

Why would you want to do that?

With a FADEC that has frozen at (say) 20% just open the throttle when more power is needed (coming to a hover?)

You would not want to overtorque/temp one engine when the other has a perfectly serviceable manual throttle reversion that will allow you to fly (carefully) almost any profile

135 manual fuel
 

You should theoretically be able to trash the engine with excessive fuel if operated manually, since there is no supervision of the engine limits.

With full FADEC fail of one engine, you will also lose the TQ and TOT figures (its a function of where the data routes through the FADEC black boxes, whereas the N1 is direct from the motor) and also the FLI needle since it has lost 2 of 3 inputs. You can only match engines by N1 figures. This is quite fiddly, especially with stiff twist grips. An easy procedure starts with noting your take off TQ and N1 figures.

With a FADEC freeze at 20-25% TQ leave it alone as you should have sufficient power for climb, and be able to descend.

On finals, as power demand builds up thru 7.5 FLI on the good engine, set manual engine to the hover N1 figure and leave alone. This will give you both engines for hover landing. Lowering the collective, wind off power to avoid Nr rise. :)

Hope this helps.......from an EC135/145 beefer.

Hi Eddie1

To answer your question (based on my understanding of the system so could well be wrong!) yep if you keep raising the lever the good engine will continue to provide more power right up to 128% TQ (and beyond if you droop the Nr below 95%)

Whilst we aim to keep both engines below 75% TQ (on a T2) as we come to the hover, FLI 10 is actually a gearbox rather than an engine limitation so the good engine is not exceeding its limitations by going into the 2.5 minute power band. That is not to say that you won't reduce the life of that engine by using more than FLI 10, that would be up to your engineers and the TM manuals. However a mis-handling of the manual throttle leading to an overspeed or overtemp may well write the engine off!

Ox, I also find it helpful to raise the lever while in stable flight to get an FLI reading of just under 10 on the good engine. If you then note the N1 of the good engine that will give you a maximum N1 figure to open the manual throttle up to for landing.

Hope that helps.

TeeS

Just a note, based on my last IFR training flight (where my instructor failed to activate train mode and turned one engine to IDLE).

The engine has a 2.5 minute limitation and based on what we got back from eurocopter, transmission has only 2 minute limitation (not noted in any book to my surprise).
Our flight on one engine lasted for 1' 52'' so we avoided the 2' limitation by just a fraction. The engine was limited by the amount of TQ and time. 2,5' being absolute top, but at a TQ value we were at ~112% (dont hold me on that one, takem from what i remember) ment that we just made it with a 1' 52'' so the engine didn't come off. The transmission has a notice for this event, as if one XMSN chip light comes on, the transmission is of to germany.

Hi eddie,

"If you have one engine freeze at 20% Torque can I pull the 128% with the other engine? Will the FADEC of the good engine approve the 128% if the failed engine is officially only "freeze" not "eng fail". What is max. possible TRQ?"

As long as you have frozen the "ill" engine below 30 % Torque you will have the OEI-Power on the "healthy"engine. But as others already stated, why not set the Torque of the frozen engine manually as much as you need it?

Best regards
Tom

@echelipilot
so if one engine produces less than 30%TQ, the Fadec assumes OEI-Limits for the other one?
From where did you get this information? I`ve found nothing in the approbiate manuals...

skadi

Hi Skadi,
"@echelipilot
so if one engine produces less than 30%TQ, the Fadec assumes OEI-Limits for the other one?
From where did you get this information? I`ve found nothing in the approbiate manuals...
skadi"

I´ll check the books when back on duty next week.
regards
Tom

eddie1 - That's one that had to be shut down in 6500hrs flying - so it's actually 13,000 engine hours. There will be plenty of engines that have flown the full 3500 TBO without problem, and so the average that will make up the certification figures.

As to your other question, the answer in my boook is No you shouldn't but Yes you can and FADEC will give you as much as you want. Basically, if you have one engine providing power, taking the other into the OEI zone is possible (the only Tq limiting factor is your left hand) but, if you do it, the engineers will be talking to ECD & doing over-torque checks on the transmission. Following the Flight Manual "If flight situation requires max engine power, Tq setting of affected engine may be increased" or similar, should be observed. :ok:

If both engines are running, even with one operating at a lower than optimum level or frozen due to FADEC malfunction, you are still in an All Engines Operative condition (they are both still working all be it one in manual) therefore you should observe the AEO limits.

But at which constellation is the system changing from AEO to OEI-Limits respective OVERLIMIT Indication? I think, thats the reason for the original question.
Is it TQ<30% on one engine or 0%TQ, is it related to N1 of the faulty engine?
Its a theoretical question, beside the option of manual override!

skadi

The good engine doesn't know and doesn't care how much power the other engine is producing. When the other engine Fadec fails, it stops communicating with you and it stops communicating with the good engine. That's why you get a 'DEGRADE' caption on the good engine.

It makes no difference to the good engine whether the failed engine is producing 10%Tq or 100% TQ, it will make a difference to the gearbox though!

TeeS

skadi - and your other questions re Tq etc.

There is no changeover to OEI limits, they're on the FLI all the time, it's only the start limits that appear & disappear. The Flight Manual tells you that the 2.5 min countdown timer activates as soon as either engine exceeds OEI MCP - but it still stands that taking one engine over OEI MCP, whilst the other is producing power, will result in a XMSN over-torque.:=

In AEO you get the red LIMIT light with gong at 75% TQ ( T/P2 ) and an steady engine exceedance for >80%/10sec. If you are OEI , you can pull more ( 86/125/128% ) MCP or time limited without the above mentioned light/tone at 75% . Thats what i meant with "change to OEI mode" . So there must be some information going to the FLI to decide whether ist OEI or AEO?

skadi

Guys this is not torque related. The system senses an engine fail (and displays ENG FAIL on the CAD) when it senses less than 50% N1. When this occurs it changes to the OEI limits. That said the engine is still running but only just.

Try winding off the twist grip next time you shutdown (make sure you go the correct way) you will see it happen before your very eyes.

A lot happens at or less than 50% N1. ENG FAIL caution, start cycle terminates and Fire bottle discharges if EMER OFF Sw pressed.

But if you put one Eng in Idle ( >50% N1 ! ), you can still pull 86% MCP on the other one without red LIMIT . Thats what we did for OEI training before the "training mode".

skadi

Quite true Skadi, however if you are still talking about post Fadec failure, selecting idle will do nothing because the switch just tells the Fadec to put the engine to idle. Sadly the Fadec is not listening to the switch at this point because it has failed/frozen.

Cheers

TeeS

and you have a FIRE indication.

Otherwise all the EMER OFF does is close the fuel valve.

Thank you Shawn. For some strange reason I found your post today.

If I understand correctly, than there is no safe procedure for a T/R failure in a hover, lets say under 500ft AGL? I remember a japanese 135 video crashing while at slow speed, low height maintenance flight.

I'm asking about this because my colegues retured from 135 sim with an idea about this. After fenestron failed in a hover 1500ft AGL they tried gaining airspeed while spinning and 1500ft wasn't enough height-red screen. Than they encountered the same situation, stopped spinning by rolling off the twist grips, entering autorotation, gaining airspeed and while at more than 65kts, roll back on the twist grips and you have T/R fail during cruise flight scenario - more survivable. They lost about 1000ft height during that maneuver.

FADEC Fail - AEO-OEI Limits
 

Hi skadi,
basically the information is from several training flights with our TRI´s. It seems that there is no written information, for example in the FADEC-system-description which says “If TQ is 27 % you have OEI Power on the good engine”. The only written evidence I could find is a NOTE in the “FADEC Fail” emergency procedure (EC 135 P2, page 3-22).
“If the flight situation requires maximum engine power, …….tq-setting may be increased. ….Do not exceed the N1/TQ value of the normal engine and the AEO limits.”
Cheers
Tom

Hmm, that's valuable information that should be entered in the FLM. Some facts about the EC135 are just not stressed enough in the FLM.


There is one more thing about these "windows" helicopters that I don't understand. A few cautions on the CAD have the importance level at which the manual says "don't start the engines, don't fly..." if one of these appears. One example is "check CAD for no INP FAIL or CAD/VEMD FAN..." that may be listed on the second page of CAD and not straight forward visible to the pilot. Why isn't the system capable of filtering those out and write accross the whole CAD screen "DON'T START, press F1 for more details". It's a straight forward caution or warning using plain logic.