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noam
19th Feb 2014, 12:23
Hi,
Having trouble starting the Arriel 2b (AS 350 BA) engine first time every day.
It takes about 10 sec after moving the FFCL forward to have the TOT response, and then the TOT runs very fast so I must take the FFCL back a bit in order to avoid hot start. when starting second time and on, it is very smooth and the rising of the TOT is fully controlled.
Does anyone have encountered this kind of problem? If so, any ideas?
Thanks

victor papa
19th Feb 2014, 12:35
What does the batt amps and volts do during the first start?

BH06L3
19th Feb 2014, 15:34
I had a similar experience with a BA about 4 years ago. It would almost top out and then usually only ignite around 20% N1. We changed a bunch of parts finally fixed it a good while later after a few months of trouble shooting. But sorry can't remember what was actually changed that fixed the problem. I think that engine restricts and only introduces a very limited amount of fuel until around 20% where it then allows the selected amount fuel to be added. I think that was were the problem was, but I'm only a pilot with a bad memory so sorry not much help.

alouette3
19th Feb 2014, 15:48
Victor Papa is right. Since it is the first start of the day ,you may have to watch the voltage drop when you hit the start button.If it drops close to 15V or so, it may be time for a new battery.If the amperage demand is excessive ,it may be time for a new starter-generator. But, since you say it works great the rest of the day, I would say it is the former.
Alt3.

I-IIII
19th Feb 2014, 15:51
To my opinion is starting with a ramp injectors and not as usual with injectors.This is confirmed when the engine is hot you dont have any starting problems.

Art of flight
19th Feb 2014, 16:12
I'd say that the battery amps are the simplest and cheapest thing to diagnose. Most starting problems are just simple battery discharging overnight.

icedriver
19th Feb 2014, 19:55
Check your igniter boxes. Sounds to me like you may have had a box or igniter fail.

jayteeto
19th Feb 2014, 21:42
A huge percentage of car breakdowns are due to battery failure. This is also usually the cheapest part to replace. Even if it doesn't cure the problem, you will not have wasted your money. Consider using a power set for the first start to confirm if the fault is still there.

hueyracer
20th Feb 2014, 04:23
Never flew this aircraft-but it does have the "upstairs" fuel control levers, right?

In our aircraft (BK117C1) we had that problem from time to time….changing FCU did not help…..

We figured out that it was the "wire" going all the way back to the engine..

During the night (when it cooled down) it lagged….and in the morning, when we started, the FFCL was indicating 20-but the engine only showed 15.
So when starting-nothing happened…so the pilots moved the lever forward-and wham-to much fuel in the engine..

It helped to move the lever forward all the way, and then back to 20…..

Checking the primes (if your aircraft has them-never flew the AS…) might also help...

RVDT
20th Feb 2014, 11:26
BOOST/PRIME On for 20 seconds before you start it?

As per RFM.

eunecte
21st Feb 2014, 00:39
It's probably not the batterry.

1- 15 volts and more when you hit the buton you are good to start it.
2- look for good blue spark at igniter for 10 sec.
3- Look for good spray pattern at the start fuel nozzle when you remove it and simulate a start. ( check for proper shimming
4- Might be the start drain valve that leak fuel back to tank.
5- Might be clogged start electrovalve.
6- might be pressurizing valve( remove the be nut and look for fuel with boost pump, if their is you have a problem.
7- Bad FCU

I when throught that last month and it was a bad FCU.

The Tox
21st Feb 2014, 10:28
You're kidding us, aren't you? Why are you troubleshooting this problem here and not with your engineer/mechanic and what is he or she doing about it? Check the troubleshooting guide in the Engine Manual not a rumour network!

BH06L3
21st Feb 2014, 12:05
I don't see a problems asking around this forum. We had a very similar problem with ignition on the same aircraft which was the worst on first start. Our DOM called Eurocopter, friends, other operators, AMO's, and it wasn't a quick or easy fix to figure out. Eventually the aircraft was fixed. The more ideas the better.

Fun Police
21st Feb 2014, 12:10
i have seen this in 1D1's and on each occasion it turned out to be incorrect shimming of the igniters (as mentioned). one of these was on a 0 time engine from turbomeca.

no harm in asking here as far as i can see, as long as responses are not treated as gospel and the usual caveats are kept in mind.

OP; good luck

dugi212
21st Feb 2014, 18:57
Turbomeca has a problem with fuel preasure after 24 hours , try first start in a day :ignition out , starter on , move throtle to iddle an back , after that normal start. I had that situation on BKC1, of course batt. should be good
Best regards