EC135 ARRIUS2B2 start problem

[Icaros212]

Good night to everyone.

During the first start of the day the engine always makes a restart, on other flights always starts well. Has this happened to anyone? Does anyone know any solution?

Thank you very much in advance.

[albatross]

What is a restart?

[hueyracer]

One of the issues in aviation is the failure to communicate to engineers.....

1. Which engine is it we are talking about-°1 or °2?
2. How old is this engine?How many hours does it have?
3. How long has the problem been there?
4. What was changed/repaired before the problem occured?
5. What is the temperature/humidity/elevation for this problem?
6. What are the figures on start (battery voltage, Eng Oil Press, Eng Oil Temp)?

[Helilife100]

It's almost certainly air getting into the fuel system. The first possibility is air entering the HMU through it's engine pad seal. Take a look at the clear plastic tube running from the pad and see if it is full of fuel. If so ,then change the HMU.

[jayteeto]

Information for non 135ers, if the engine doesn't start first time, it does an automatic restart sequence. Ours would do it when it was cold and damp/volts were low or insufficient fuel priming had been done.

[MightyGem]

Never heard of that. I obviously never had one that didn't start full time.

[handysnaks]

Care to elaborate on what you mean by 'automatic restart sequence' JT?

[skadi]

Information for non 135ers, if the engine doesn't start first time, it does an automatic restart sequence. Ours would do it when it was cold and damp/volts were low or insufficient fuel priming had been done.

Never heard that either in my 19 years flying the 135....

skadi

[jayteeto]

Our police cab didn't have the modification Dave, that is why you didn't see it!
If you carry out a start and it fails to light up, the starter motor cuts out, winds down and then at a specified rpm it attempts a restart. Can't give you the mod details because I can't be arsed looking!
Your later aircraft may have had the mod, but it never failed to start. We went through a month of this happening regularly, I have only seen it once recently

[skadi]

And how does the modification handles the required cooldown times between startergenerator activation?

skadi

[SilsoeSid]

... and does that mod also take care of the vent run?

[jayteeto]

The start/restart happens pretty quick, you don't bust the run time. Sid, as for the vent run, who knows? It just does it! Get the engineers to explain it! As I said, it does it and it's legit. That's good enough for me

[MightyGem]

Our police cab didn't have the modification Dave, that is why you didn't see it!
Glad about that. Thought old age was starting to get me. :)

[FloaterNorthWest]

Jayteeto,

Think it's TU 130 or 160. The Arriel in the 145 does it too.

FNW

[SilsoeSid]

The start/restart happens pretty quick, you don't bust the run time. Sid, as for the vent run, who knows? It just does it! Get the engineers to explain it! As I said, it does it and it's legit. That's good enough for me

Jay, if I may use part of your 'location details'; "calm down, calm down kinda!!"
:hmm:


https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiOgZbV5s7QAhUBDcAKHf4fAJEQFgguMAA&url=http%3A%2F%2Fsavback.se%2Fdownload.php%3Fid%3D3003&usg=AFQjCNHJSGeXNjLP1m3CJaj6Lllsx-JX0Q&bvm=bv.139782543,d.d24

ESB 319-73-2130
Rev No: A
EECU software update, to improve engine starting TU-130.
Valid for T2 a/c, with EECU post TU128. Valid for 0214.
Both EECU's to be mod simultaneously.

[jayteeto]

Thanks chaps, I was getting frustrated at the mini inquisition, I'm not exactly a "books" man.
Frustration apart, it's a handy modification, I have seen pilots snag the aircraft when they witness it for the first time!

[SilsoeSid]

Doesn't tell us much though!

Isn't it a bit strange that this mod has been implemented, with few knowing what it is and what it does?
I wonder, should the engine shut itself down and then try to restart itself, wouldn't some of us think wtf! and move the engine switch to off?

[TeeS]

This may be of use, I wrote it in an attempt to explain the difference between the starting logic of the EC135 (with TU130 embodied) and the EC145T2. I hasten to add that it is my understanding of the accumulation of information from Turbomeca, Airbus and the relevant RFMs - on that basis it may not be exactly what was intended by the manufacturers :-)

EC135 ARRIUS 2B2 and EC145T2 ARRIEL 2E STARTING LOGIC

Both the EC145 and the EC135 (where Turbomeca Service Bulletin TU130 has been installed i.e. all BAS aircraft) will automatically attempt a second engine start in the event of a failed first start.

There is a tendency for us to abort a start, in the absence of a TOT rise, within a few seconds of selecting IDLE/FLIGHT; however, it is important that the start cycle is allowed to continue through the full automatic re-start sequence UNLESS the circumstances requiring the start to be aborted (listed in the relevant RFM Sect. 4.4.1.2) are met.

For the EC135:

1. ENG MAIN Sw - Select IDLE/FLIGHT as appropriate – Start clock

2. Monitor for conditions in CAUTION note RFM 4.4.1.2 – Abort start only if conditions met (including starter still running with no light up after 15s)

3. If N1 initially rises to 11-19% and then reduces, with no TOT rise, leave ENG MAIN Sw in IDLE/FLIGHT – (Note, the automatic restart process should commence in less than 15s)

4. N1 will reduce to approx. 11% and starter will re-engage (automatic restart) – note time or restart clock

5. Monitor for conditions in CAUTION note RFM 4.4.1.2 – Abort start if conditions met (including starter still running with no TOT rise 15s after automatic restart commences)

6. If automatic restart is aborted for no TOT rise

a. leave ENG MAIN Sw in OFF position for a further 30s
b. carry out 15s vent run in accordance with RFM 4.10
c. leave ENG MAIN Sw in OFF position for a further 30s
7. Repeat items 1 to 5 above (having ruled out pilot error e.g. prime pumps left off!)

8. Leave ENG MAIN Sw in OFF position for 30 minutes – seek engineering advice

NOTE - In the event that the engine does not light up immediately fuel may issue from the exhaust, this fuel may ignite when light up does occur. Fire guards should be briefed that if the flames are confined to the exhaust area and extinguish after a few seconds there is no cause for concern.

For the EC145T2:

1. ENG MAIN Sw - Select IDLE/FLIGHT as appropriate – Start clock
2. Monitor for conditions in CAUTION note RFM 4.4.1.2 – Abort start only if conditions met

3. If N1 initially rises to 17-20% and then reduces, with no TOT rise, leave ENG MAIN Sw in IDLE/FLIGHT

4. N1 will reduce to approx. 10% and then the start ignitors will be energised and fuel will again be fed to the injectors; however, NOTE: the starter will not re-engage unless a TOT rise occurs*

5. Monitor for conditions in CAUTION note RFM 4.4.1.2 – Abort start only if conditions met or if no TOT rise 30s after starter engaged

6. After aborted start for no TOT rise:

a. leave ENG MAIN Sw in OFF position for a further 60s
b. carry out 15/20s vent run in accordance with RFM 4.4.1.2
a. leave ENG MAIN Sw in OFF position for a further 60s

7. Repeat items 1 to 6 a maximum of 2 times followed by a 30 minute cooling period – seek engineering advice

* Because the EC145T2 automatic restart does not re-engage the starter unless there is a TOT rise, it is possible that pilots will think that the automatic restart process has not taken place even thought the restart logic has worked correctly.

NOTE - In the event that the engine does not light up immediately fuel may issue from the exhaust, this could ignite when light up does occur. Fire guards should be briefed that if the flames are confined to the exhaust area and extinguish after a few seconds there is no cause for concern.


I hope that is of some use.

Regards

TeeS

[skadi]

TeeS, thanks a lot for your info. Since I fly now 99,9% P/W and just one unmodified T2 from time to time, this mod was unknown for me.

skadi

[RotaryWingB2]

It's likely to be one of the air valves on the engine. If you PM me I'll dig out the part no of the part, i recently rectified this same problem on a EC135T2+.

[albatross]

Not aircraft or engine specific but..
In Canada we used to burn Jet-B.
With the demise of Jet-B we were obliged to use Jet-A or A1.
It became normal, on occasion, to have a flameout on the first start of the day on a "Cold Soaked" helicopter which had not been preheated.
Wait a minute or two and restart...no problems for the rest of the day.
I miss Jet-B.

[nodramatwo]

As Helilife100 has said, the 'auto re-start' on a TU130 modified engine is most frequently triggered by air in the fuel of the HMU system during start.

There can be several reasons for this:

The most common I encounter is if there has been a maintenance action that disturbed the HMU fuel system prior to the start. For example, the HMU has been removed/refitted or replaced, the fuel filter has been replaced, or sometimes if the main fuel line has been disconnected for a supply tank de-fuel.

As Helilife100 stated, if the HMU splined drive shaft seal is leaking badly (lots of fuel in the plastic drain tube), air can find its way into the HMU. The seal can be replaced in a couple of hours.

A known problem is also air leaking past the seal of the metering valve cover on the HMU. This can be rectified by SB 319 73 2838 which introduces an improved seal and cover. Again, the HMU doesn't have to be sent away and can be fixed in a couple hours.