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-   -   AS350 Astar/Squirrel (https://www.pprune.org/rotorheads/229370-as350-astar-squirrel.html)

Devil 49 23rd Oct 2002 17:56

Now I feel really bad-I can pull 100% NG at 3000 hp and 22 C, and not hit tq limit in cruise...

Turbomeca is on a call back, forwarded a pile of numbers from previous power checks.

My opposite got a sat power check with a max power climb to 3000, establish cruise and then autorotate to 2000 for the power check, or so he claims.

chopperdr 31st Mar 2003 02:59

as-350 b3
 
looking for operator feedback concerning the as-350 b3 with crash attenuating seats.
question: do you find the cyclic grip too low, or uncomfortable, and would you be interested in an adaptor to raise the height of the cyclic grip.
thanks

tigerpic 4th Apr 2003 23:14

as350b3 normal procedures
 
i wished the world could be more black&white when it comes to helicopters.

starting up and shutting down the arriel 2b engine is described in the operating handbook something like this:
- to start the engine, go from OFF to ON (flight) with the starting selector, except when below -20 deg C when you must wait until oil temp is >0 deg C before switching to ON.
- shutting down: after setting down the helicopter, wait 30 sec on full RPM (flight idle) and the go from ON to OFF directly with the selector

the technicians in marignane, france, told us that the shutting down procedure is to prevent carbon build-up in the engine.

what happened to the cooldown issue? i was at the american eurocopter factory, and the test pilot told me what the book said as stated above, but good procedures was to wait at IDLE both up and down.

what do you b3-pilots out there think? what do you use for procedures?

cheers,
tigerpic

John Bicker 5th Apr 2003 00:53

Believe the frenchman. I remember guys coming from Allisons to the Arriel and doing 2 minute rundowns. Longer on the Arriel is not good for it. The temperature in the bearings initially goes down but after 30 secs it goes all over the place. The problem is low oil flow at idle. In fact if you do idle an Arriel it is better to run it back to "Flight" for a period prior to shutting down. Operate IAW the RFM, simple.

cpt 7th Apr 2003 01:38

I have always complied with the RFM on the B3. This sort of procedure, based also on experience, is not lightly determined by the manufacturer, and untill now I have never heard of something different.

Steve76 29th May 2003 20:45

Astar Engineer req.
 
Hey Lads,

Does anyone know anybody with an Astar engineering ticket who needs some work for the Canadian season?
It will be contract on fires with employment during winter at a major SW Ontario city. Really good conditions and a great boss.

Immigration assistance will be provided for the right person.

Kinda getting urgent too....

Thanks in advance :ok:
Please contact:
[email protected]

Rob_L 30th May 2003 15:38

email address is failing, can you correct

Steve76 30th May 2003 21:28

Mate,
There should be a underscore between the collective and bias. I think the underline is absorbing it.
Try again and if it doesn't work I will get another address for you.

EESDL 18th Jul 2003 20:17

Thanks, thought there would be more to it!

beetlenut 26th Jul 2003 14:23

AS350 info wanted pls
 
Hi all,

Can anyone clarify the system used to record cycles operating the AS350.

I can understand 1 start--shutdown = 1 cycle...............but have been told a percentage of a cycle is recorded each time during a landing when N1 reduces below ???%

Can't remember the figures.....................anyone?


Cheers

Bn

Devil 49 26th Jul 2003 21:16

Without cycle count sheet or RFM handy, I hope the following is helpful-
A normal NG cycle is one start and warmup, takeoff, and 30 sec ground idle cooldown. IN that instance, your cycles would be determined by your maximum NG, a K1 value.
In the real world, you may have many power changes with various high power settings, the highest of which would determine your K1.
You could also have low power settings between starts, so you add a cumulative K2 to the max K1.
Example- I start and takeoff, normal power on approach and cooldown- max Ng 96%, cycles logged 0.6.

Alternate, 1 start and takeoff 96% Ng, K1 0.6, log 0.6 cycles
HOGE power check, max NG 97%, new K1 0.7 log 0.7 cycles
Agressive approach, min NG 85% adjust cycles with a K2 of 0.1, terminate at hover without exceeding previous high NG. No change K1, cycle calculation K1 0.7 + K2 0.1 log 0.8 cycles.
I land from hover and roll back to ground idle, adding a K2 of 0.15 to previous 0.1, total K2 0.25. If I shutdown, cycles would be K1 0.7 + K2 0.25, log 0.95 cycles.
NO engine shutdown, max power departure 100% Ng yields a K1 of 1.0. Then sobered by previous hairy approac, I make a normal power on approach (without exceeding previous high NG) to hover, land and cooldown. Cycles K1 of 1.0 and sum of K2 0.25, Log 1.25 cycles.
Not as complicated as it sounds. Max NG between starts equals K1, add sum of K2 events yields cycles to log.

Jez 27th Jul 2003 08:24

AS350 Info
 
After just starting to operate an AS350 along side our Bell 412 I know what you are going through .

I made up this sheet for our pilots to help work through the calculation of NG cycles. This will have to be read in conjunction with the table of Max. and Min. NG found in the Maintenance Manual (Arriel).

Hope it helps

Arriel 1B Cycle Counting:

(I) REFERENCE CYCLE (Ng): Theoretical cycle used a reference for setting service life limits. Includes one start, one power acceleration corresponding to the "takeoff power" and one shutdown.

(ii) OPERATING CYCLES: A flight may consist of two types of cycles:

- Complete Cycle: An engine operating sequence including one start, one power acceleration and one shutdown.
- Partial Cycle: An engine operating sequence corresponding to a power decrease followed by a significant increase without engine shutdown. It may be defined as the number of hover events and landings.

(iii) Free Turbine: All components. One flight = One cycle

Gas Generator Equation: N = K1 + (n x K2)

K1 = Coefficient corresponding to maximum Ng (see table over page)
K2 = Coefficient corresponding to minimum Ng (see table over page)
n = Number of partial cycles carried out between start and shutdown

;) :confused: :confused:

Arm out the window 27th Jul 2003 16:17

Absolutely impractical, is it not.
You'd think in this day and age of dirt cheap computers someone would be able to design a $20 box that would record it all for you, eh?

paco 28th Jul 2003 07:22

Quite agree - I've got better things to do than count how many times I've w*nked the handle

Phil

Dynamic Component 28th Jul 2003 08:43

beetlenut,

We use max NG pulled during the flight + min NG used(only 85% or below)x the amount of times you droped the collective below 85% inflight for NG cycles.
NG95=0.6,NG96=0.65,NG97=0.7
NG81-85=0.05

I can't remember the rest of the figures, but you can find them in the Turbomeca Manuals.
As for NF cycles, 1 startup +1Flight +1Shut down= 1cycle

bellsux 28th Jul 2003 10:13

If your boss has enough coins in the bank you can buy a cycle counter that works it all out for you but it is pretty straight forward to record the cycles after a while when you get your head around it.

beetlenut 1st Aug 2003 19:19

Thanks to all respondents, think these comments sum it all up




Absolutely impractical, is it not.


Quite agree - I've got better things to do than count how many times I've w*nked the handle
Especially on a up/down/up/down survey trip the number of landings gets a bit blurred.

Cheers BN

Giovanni Cento Nove 1st Aug 2003 21:15

It seems you may have "summed it up" without any thought about the consequences. In a country that seems to have "diificulty" counting hours and cycles maybe you should have asked your maintenance engineer "Why?".

Apart from the possible financial implications it has a lot to do with the design of the engine..

The catch is the injection wheel. This wheel is subject to considerable thermal cycle fatigue. If it fails, most of the gas generator rotating assembly will leave the engine rapidly. It has been proven a few times, so don't bother.

There are units which will record what you want - 1 is a tacho box from Turbomeca and there are a few aftermarket units. Or is this a case of "can't be arsed?"

beetlenut 2nd Aug 2003 16:42

GCN Maaaate!!,


It seems you may have "summed it up" without any thought about the consequences. In a country that seems to have "diificulty" counting hours and cycles maybe you should have asked your maintenance engineer "Why?".

Nope, you got me completely wrong. This system is impractical and can be a challange to keep correctly. I personnally will get a "click counter" to ensure my tallys are right.

It just seems stupid that these "after market" accessories are not included in the initial A/C build.............. a bit like auto-relight systems (don't get me started).

Cheers BN

PS: I dont think everyone has problems with truthfully recording Hrs or Cycles.

Buitenzorg 25th Oct 2003 04:14

AS350 BA Wt & Bal
 
Don't have a flight manual handy, and I'm looking for the wt & balance information for the BA model Astar - Squirrel for Europeans. Basically, all the info required to calculate a weight and CG position - weight/CG envelope, cg positions and limits of seats and bagage compartments, etc. - except for the empty of the individual machine. Browsing the web hasn't turned up anything, does anybody know a website with this info?

Many thanks in advance.


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