PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Rotorheads (https://www.pprune.org/rotorheads-23/)
-   -   As 350 B3 (https://www.pprune.org/rotorheads/300673-350-b3.html)

UnDies 16th Nov 2007 11:24

As 350 B3
 
Gents/Ladies - with the fadec system on the B3 is it still required that one should crank when needed? I’ve been told that the Fadec takes care of everything but that’s it’s always healthy to crank a hot turbine(and I`m talking about the B3 specifically) before starting but not a necessity and, if any, what would the downside be to not cranking?

arismount 16th Nov 2007 12:59

Not in my opinion
 
Haven't flown a B3 but have experience with the 2B1 installation in the B4 and it's the same. The dual-channel FADEC does indeed seem to take care of everything quite well on the starts.

I've started within 5 minutes of shutting down in temps ranging from 37C to -10C and in tailwinds without cranking, and have never noticed a problem.

Of course one should always been focused on T4 during a start and prepared to abort if there's any indication of an incipient hot start. This applies to all turbine helicopters, all the time.

However, the single most important factor in getting a good start is to have a strong battery, and using battery power to crank and reduce residual engine internal temp is a waste IMO.

If a pre-start crank was "necessary," the RFM would prescribe it. It doesn't. So draw your own conclusions.

JimEli 16th Nov 2007 15:01

>
The B3 does NOT have the same fadec as the B4. It is not a dual channel fadec therefor yes it is always a good idea to crank the engine if you feel it is to hot for start...
<

Grain of salt warning: there exist several versions of the B3.

maxtork 16th Nov 2007 15:06

Jim is correct. The newer B3s come with the same FADEC as the B4 being dual channel.

I-IIII 16th Nov 2007 19:05

re
 
the b3 plus is fullfadec dual ch,the old b3 was not full fadec but anyway don't need crank in both versions

oscar bravo 17th Nov 2007 03:11

So the B2 came before the B3 and the B3 came before the B4?!!?:}

I-IIII 17th Nov 2007 08:12

re
 
YESSS:ok::ok::eek::eek:

UnDies 17th Nov 2007 11:06

Mixed feelings
 
I fly the newer B3 with the dual FullFadec system - it seems there are some mixed feelings about the cranking option. There must be a reason why it was included as an option......I guess there`s no harm in cranking when needed.

I-IIII 17th Nov 2007 12:02

re
 
there is for wash the compressor:E
anyway if you have hight t4 during start the fadec is gettin start more slowly if t4 is greater than flight manual parameters will cut the start (you have to go overparameter more than 1 second) very easy

widgeon 17th Nov 2007 17:54

Oscar Bravo , full chronological order is B ,D BA , B2 . B3 , eC130 ( b4) , there are also DA and D2 FX1 and Fx2 models ane one or 2 allstars ( C30 engine )

Was there ever an A model and what heppened to the C model

I-IIII 17th Nov 2007 18:04

re
 
b3 plus also.......:O

rotorpol 18th Nov 2007 11:39

As 350b3
 
Hi
I fly B3 single channel fadec, so the old model.
I fly it daily in sling load operations and perform many starts a day.

We Never, repeat never crank before start regardless of T4, the Fadec takes care of the fuel adjustment, therefore controlling the temp.There is no need to crank, thats what the fadec is there for.

:ok:

Hiro Protagonist 18th Nov 2007 12:34


I fly the newer B3 with the dual FullFadec system - it seems there are some mixed feelings about the cranking option. There must be a reason why it was included as an option......I guess there`s no harm in cranking when needed.
Check out your Emergency Procedures... Fire during start...

UnDies 18th Nov 2007 15:17

Thanks
 
Thanks for all the posts - Have come to the conclusion that cranking, although not needed, is a healthy habit to have regardless of whether it is needed or not.

Safe flying yo`ll :ok:

antonk 18th Nov 2007 18:57

Cranking B3
 
I spoke to Eurocopter SA (Lanseria), and they informed me that it is NOT nessessary to crank, although the chief pilot says he does if the T4 is above 150 deg.

I-IIII 18th Nov 2007 22:47

re
 
make no sense crank in b4 and b3 plus absoluty no sense.Is use battery for nothing

I-IIII 18th Nov 2007 22:49

re
 
make no sense crank in b4 and b3 plus absoluty no sense.Is use battery for nothing.I will pay for your damage....try start up with hot engine and strong wind in the tail and tell what happen.........the start shoul take 10 second more........

Dynamic Component 18th Nov 2007 23:04

widgeon,
You forgot the B1.

We also have the B3 with the 1B engine in it and do multiple starts a day. We have always been told to monitor the T4 and abbort if need be, but cranking out in the bush leaves you with a chance for no start at all if the battries don't like it.

Just my 2c:}

I-IIII 18th Nov 2007 23:11

re
 
yes is very easy cannot start because the battery is 1 or 2 volt below normal voltage

Squirrel 19th Nov 2007 02:43

For the EC120, the RFM says crank if T4 is >150 (EC120 is not fadec). There is nothing in the B3 RFM to crank prior to start - it is not needed. I've started the B3 within 30 seconds of shutting down (yes, even on a hot day & even numerous occasions of tailwinds during start), the FADEC takes care of everything. What you have to do if it starts to go hot (ie: caused by the FADEC having a glitch vs. T4 hot prior to start), is shut off the start switch. That is why you should hold onto that switch during start.


All times are GMT. The time now is 09:34.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.