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-   -   Guimbal Cabri G2 (https://www.pprune.org/rotorheads/296022-guimbal-cabri-g2.html)

Hughes500 13th Feb 2014 07:17

HH

Please tell me how much heavier a fuel injected engine is compared to a carb ? If you put a carb in your hand and an injector there is very little weight difference ! Would have thought fuel injection was more efficient !

HeliHenri 13th Feb 2014 08:46

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H500,

I do see your point but as you already know, my surname is Henri, not Bruno so I don't have all the real elements concerning the integration of the engine in the G2 to answer.

If you are waiting for an aircraft that suits at 100 % all your needs, unfortunately you will have to be very patient and you're well aware of that.

I don't know why (really just a feeling) but I'm almost sure that you will take a decision before the end of the year :)

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FLY 7 13th Feb 2014 08:54

I would have to agree with the other comments about the carburettor and carb heat.


I've followed the little G2's development with casual interest, and there's a lot to commend it. But, in terms of an advanced design, the use of a carburettor fed engine seems very contradictory.


It may well work fine, but an unnecessary step backwards IMO.

heli1 13th Feb 2014 09:35

I hesitate to join this discussion but having flown a two seat helicopter with fuel injection for the past 20 plus years,I have found it reliable and worry free.Every one less thing to think about ticks my box.

John R81 13th Feb 2014 10:07

I have flown the G2 (very short) and liked it. I would like it even more with fuel injection. Shortly (this month?) I might have more regular access to a G2 and then build some hours so the carburettor is not going to keep me out of the machine but I am not buying one yet either.

If I were in charge of rules, I would not allow certification of any new carburettor engine for aircraft or certify the design of any new aircraft that used an existing approved carburettor engine. There is additional risk over the proven alternative of FI and it is risk that we don't need to take. I would like to see carburettor engines phased out of aircraft (not trying to stop any existing machine from being flown / manufactured / sold). Perhaps such a rule change is the only way to ensure that we move on.

HeliHenri 13th Feb 2014 12:30

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Hello JR81,

You're going to fly with EBG at Redhill ?:) (They should receive their new G2 at the end of this month).

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John R81 13th Feb 2014 12:55

That's the plan HH

Though when I get back to the UK Friday it will be the 120 this weekend.

Reely340 13th Feb 2014 16:13


Well, is the very good feedback given by the operators and the order book fill still next year, a good explanation to say that their choice of engine was not as bad as you had stipulated ?
No, it is not. Especially as it is not your explanation - which I was asking for - why it was a good choice. Back in the old days, Eastern Germans where cueing up to buy that plastic Trabant car. Great sales is not necessarily a sign of engineering quality.


The "stupid" Bruno Guimbal gives two reasons for that choice, weight and cost.
Here, I have to lean out of the window and claim: He is lying.

If he were right, then back in the last century Schweizer/Sikorsky would have decided just for the fun of ruining revenue and performance to modify their 300CB (carburated) training heli to a "heavier, more expensive" ((c)Bruno) 300CBi (FI) successor.
I don't buy that. :ugh:
I'd need to see serious data to back that claim.


You mean, if I have to choose between a brand new G2 and a brand new H300 ?
No. If you actually read what I asked you, you might find that I was inquiring if YOU would want to swap an FI engine in favour of an carbureted one, everything unchanged. Let me rephrase that question once again:

Given the ficticious chance, would you personally want to "upgrade" your ficticious heli's FI engine to a similarly powered carburated one, just from the technical point of view, lets assume someone else would be paying...?

If yes, please elaborate why.

malc4d 13th Feb 2014 16:32

Is it still unavailable in the US ?

HeliHenri 13th Feb 2014 16:44

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Is it still unavailable in the US ?
Hello malc4d,

The G2 should be in the US this year (as I mentionned it two pages ago ;))

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HeliHenri 13th Feb 2014 17:06

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Here, I have to lean out of the window and claim: He is lying.
Reely340,

You are going too far.

Several members of this forum know personally the person you are talking about, maybe they will add something about your statement above.

But as far as I'm concerned, I won't talk to you anymore.

.

Reely340 13th Feb 2014 18:39


Reely340,
You are going too far.
Deliberate provocation, one has to beat the bush to stirr up some answers. :p


Several members of this forum know personally the person you are talking about, maybe they will add something.
That would be great, :D exactly what I've been searching for since hearing about the G2. :ok:
If there are personal friends of him on that forum, there must be someone knowing the real reason for him choosing an icing- and low G sensitive engine configuration for his otherswise really great aircraft. :confused:

I'm pretty sure Mr. Guimbal knew about S300C/CB/CBi engine history, R22 accidents etc. He hopefully did not draw straws while designing, hence I am genuinely interested in the underlying decision leading to a carburated engine...


But as far as I'm concerned, I won't talk to you anymore.
That's a pity. You were a cute tree to rub against :E

I'd still like to hear from you if you personally really think carburated is better than FI.

And if not, I'd hoped to hear from you as many reasons as are thinkable, be them finacial (inital cost / maintennance cost), political (no FI for the french coalition deserters ?), psychological... that might justify Guimbal's decision. I really am at the beginning of my helicopter industry intrinsics learning curve, and are craving insights into its backgrounds.

The only thing I admittedly have a problem with is statemants like "I'm right just because", I do plead guilty in that respect, especially in technical discussions. I never was good at merely believing "higher authorities", w/o being presented sesible reasoning.

RVDT 13th Feb 2014 19:35

FI or Carb?

I guess nobody has picked up on the fact that the "Carb Heat" on the G2 is "Automatic" and controlled by the EPM.

There are built in "self tests" and indications of system failures.

If you revert to "manual" or have any doubts you should select "HOT" whenever below 80% MLI.

Carb definitely starts a lot easier. FI has its own little foibles and is not the only answer.

With respect to FI - Lycoming would have to certify another engine as there is no equivalent to the current 360 model as used that is injected. It is not a case of just bolting an FI system on the existing engine.

A carburetor is lighter and cheaper to overhaul and or repair. USD 500.00 versus USD 5000.00.?

As to the zero G cuts - what were these people doing? If it was the competition the rotor probably would have departed as well.

The aircraft was developed personally by Bruno and first flew in 1992. I think his solution is a pretty good one.

Anybody ever experienced icing in a G2? Possibly not.

http://www.aviastar.org/foto/guimbal_cabri.jpg

Hughes500 13th Feb 2014 21:51

RVDT

Fuel injector on a 300 C costs £ 750 to overhaul where do you get $ 5000 from ?

HeliHenri 14th Feb 2014 06:39

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Heli Aviation (Germany) takes delivery of its eighth Cabri G2 ! :ok:

Press release*- Heli Aviation GmbH

" With the eight Guimbal helicopter participating actively in training operations, Heli Aviation is continuing to develop its global competence advantage in respect of Cabri G2 and additionally satisfies the claim of operating the largest G2 fleet in the world used in an aviation school."

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Hughes500 14th Feb 2014 08:49

Just to liven things up, pity Bruno didn't put a diesel in it ( I have discussed it with him HH before getting too excited )

HeliHenri 14th Feb 2014 08:59

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Hello H500 ;),

So what is his point of view about this subject ?

Must be interesting because if I remember well, he has worked for a firm producing diesel engines for fixed wings aircraft.

Diesel engine seems to be one of the three options examined for the G4.

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Spunk 14th Feb 2014 09:59

I'm not a fan of carburator equipped engines in aircraft either and never understood nor will understand why Bruno put one in the G2.
Frpm what I have heard he decided to do so cause a lot of pilots/flight instructors asked him to do so.
The argument was that the carburator equipped engine starts a lot easier (Personally I disagree on that one).
As far as the the zero G cuts are concerned, you really have to push it over and hold it there for a loooooong time before you get even close to cut off the engine. Not a manoeuver you want to show any of your students or to any other kind of spectators.
The Cabri is a great machine to fly with and for x-mas I want one with a fuel injector. :O


Heli Aviation (Germany) takes delivery of its eighth Cabri G2 !
Shouldn't it say SEVENTH :mad:after last weeks that little mishap :{

Hughes500 14th Feb 2014 11:11

Spunk it sums our industry up if flight instructors ( who normally have next to no experience ) asked him to put a carb in it !!
If you know what you are doing with FI then no problem. It is laughable that in 2014 we cant get a FI engine to start at a turn of a key !!! Now if your BMW or any car had the dramas that we put up with in aviation ...............
When will the regulatory bodies get their head out of the sand with certification rules. Currently Ford have a predicted failure rate of their engines of 10million to 1 bet Lycoming gets nowhere near that
G2 has a plasma start so presumably starting with FI would be no problem

HH diesel to heavy currently !! I assume too expensive to make out of aluminium ?

Reely340 14th Feb 2014 13:27


With respect to FI - Lycoming would have to certify another engine as there is no equivalent to the current 360 model as used that is injected. It is not a case of just bolting an FI system on the existing engine.
Why that? There is the proven 180HP FI engine of the 300CBi. Would it be that much a drama that it could output 35 ponies more than the stock G2's engine?

These 35 hp would have added great power reserves / hot and high capabilities / additional loading options to the otherwise great G2!

I'm still waiting for an explanation why they were not using the CBi's "heli certified" FI engine. IIRC even the mounting direction would be comparable. (e.g. no need for vertical crank..)


Carb definitely starts a lot easier.
I don't believe that either, this time from personal experience firing up FI in summer and winter:
One of our 300Cs has the standard starter, the other one some hi-torque STC(?) version. Granted they turn over the engine at different speeds but both fire up nicely, as soon as one has developed a feeling for how much throttle each type wants when cold.

Reely340 14th Feb 2014 13:54


It is laughable that in 2014 we cant get a FI engine to start at a turn of a key !!!
Basicall I am 100% with you on this one, I found out that apparently there was a long lasting dislike of any kind of electronics when designing an aircraft. To me it feels as if the engineers, while designing, constantly had been pestered by the sales guys with questions/requests like this
"and it will not rely on the battery when airborne?",
"naa, do it pnematically, no electrics please",
"jeeez, the ignition advance must be mechanical, if at all necessary"
"does the oil pressure gauge have to be an eletric instument?"
"we'd want the attitude indicator to be suction powered"
....


Now if your BMW or any car had the dramas that we put up with in aviation
*cough* a very bad example:=:
Head of IT of one of my customers drives a 320i, nicely upgrading the model every 4-5 years. He told me the story when once the engine simply died while passing, in fast lane, as if switching off the ignition. Wont start up anymore. He had it carried to the BMW mech. "Well known effect, we can fix that, we'll dump your bricked EFI controller and you get a fresh one, costs just 1500 bucks".

University collague of mine (eletronics, redundancy, automotive bus systems) claimed manufacturers see electronification mostly as cost saving feature. They do not like to over engineer their stuff to make it "russian style" bullet prove.

And IIRC the german triple-A (ADAC) once reported, that the majority of car breakdown service calls (ignoring running out of fuel :ugh:) nowadays, are electronics related.


So both things seem to hint that there HAD BEEN good reasons to stay clear of computerized systems for vital function that are not engineered with military reserves built in.

But personally I'm happy to see FADECs pop up everywhere. Honeywell has shown how far TBOs can be expanded on an individual case by case basis if something monitors engine data in real time á la HUMS. I'd say counting cycles and hours will be a thing of the past, as will hard TOT limits. The engine monitoring computer will soon output "HSI in 12:51 h from now", and the gentle pilots will be rewarded by longer TBOs. :E

cockney steve 14th Feb 2014 13:59

The automotive world had injection foisted upon it by increasingly stringent emissions requirements.
During my mechanicing days, I rapidly learned that the Bosch injection system could produce low fuel consumption and a perfect burn, as evidenced by the pale chocolate-coloured exhaust and spark-plug deposits.....However, It did not give the ultimate power...for that, you slapped on some Weber 40 DCOE's.....thirsty but delivered extra horses.
Presumably an aircraft system can be programmed differently (Chipped) to sacrifice economy for outright power, when needed.

A carb, in it's purest formis very robust, simple and efficient....I think the thousands of Rotax that have dilited the lycosaurus market monopoly, are carburetted by Bing...a simple slide and needle setup, somewhat less advanced than the constant-vacuum SU or it's ripoff Kei Hin counterpart. The SU was at it's zenith when the needle was rigidly mounted to stay concentric within the jet...the idiotic idea to spring-bias the needle so it destroyed it's own and the jet's metering accuracy,killed the product

having said that, a new biased needle and matching jet can be had for under £30, to restore "as new" performance

Single-point injection still carries a risk of icing....it's just moved "downwind" from the injector in the induction tract.......
As soon as you go on to multi-point injection, you're into an injector per cylinder and a complex and expensive box of electronics...or an equally complex and expensive mechanical injection-pump.

ISTR reading a figure of ~£500 for a full Rotax carb overhaul.....It made my eyes water,anyway!...For motorcycle use, one would expect to pay less than £300 for a complete brand-new carb//// Let's see....float-needle and seat....choke-tubeand throttle-slide.....main jet and needle....Uh,, OK the return spring to push the slide back down (never seen a worn to breaking one in over 50 years! )....that's it, other than a few caskets/o-rings....Oh, go on then, add a pilot fuel or air-needle, that must be all of £3 worth :}

You *can* get a carburetted car to ice-up in the carb. but back in the seventies, a simple flap-valve was devised by the maligned BMC a bimetal strip moved the flap between a hot-air pickup around the exhaust manifold and a fresh air pickup externally....the induced air caused the strip to bend, thus automatically altering the hot-cold balance.....AFTER this, it was filtered BEFORE it went to the carb or engine....Why do Lycosaurus still feed unfiltered hot air to an engine?

I'd agree with Mr Guimbal on this one...carb is simpler, cheaper and easier to maintainand gives the best bang for the buck .

evil7 14th Feb 2014 15:37

@ Spunk

No it should not be the "seventh" Cabri for heli Aviation.

As far as I know it was not a too big deal. It will be repaired.

A few tie-wraps, some srews and abit of paint should do the job:}.

So don´t write that helicopter off too soon:ok:

Spunk 14th Feb 2014 16:35

@Hughes500

I totally agree.

As far as turning the key I love to tell my students that Hughes came up with the idea of a starter button back in the 50's and that my car sales person was trying to convince that starting the car by simply pushing a button was something new ;-):p

We've never had any problems with firing up one of our fuel injectors (neither on the 300 C nor on the Raven II, neither at -10°C nor at +30°C). However I see our competitors flooding their carb equipped ones every now and then, specially in winter time.

Maybe the Diesel modified and installed in several airplanes by a company called "Thielert" would have been a good alternate for the Guimbal. (I think it's a modified CDI 190 taken from the Mercedes A Class)

Reely340 14th Feb 2014 17:16


Maybe the Diesel modified and installed in several airplanes by a company called "Thielert" would have been a good alternate for the Guimbal. (I think it's a modified CDI 190 taken from the Mercedes A Class)
Well, Diamond Aircraft tried just that, and almost went bankrupt due to both quality issues and way overdue shipment of the engines, especially when Thielert went tits up.:E
As usual, when you want something done properly you have to do it yourself. So they foudned AustroEngine and their DA42NG now comes with AustroEngine's AE300 diesels.

That very engine the AE300 delivers 170 hp, EASA & FAA cert. in 2009, most probably way too late for Bruno to consider as powerplant. Personally I have no idea wheter it is light enough for helicopter applications.

Reely340 14th Feb 2014 17:25

CS:

As soon as you go on to multi-point injection, you're into an injector per cylinder and a complex and expensive box of electronics...or an equally complex and expensive mechanical injection-pump.
So I thought too, until Spunk pointed me to the description of the "Lycomming O360 FI System" (by Precision Airmotive) http://www.precisionairmotive.com/Pu...s/15-812_b.pdf

Very interesting reading:
  • single point metering controlled by diaphragms and what not
  • mulit injector nozzel design, one per cylinder but in intake tube
=> absolutely no chance of icing (injector is very close to intake valve?)
=> absolutely no box of electronics

Hard to beat, regarding icing resiliance and simplicity of design, I'd say.

Bravo73 20th Feb 2014 21:26


Originally Posted by Reely340 (Post 8319067)
Personally I have no idea wheter it is light enough for helicopter applications.

Lycoming 0360 is 117kg (according to Wiki).
AustroEngine AE300 is 185kg (according to their website).

A 68kg difference. Or the weight of a passenger.

HeliHenri 21st Feb 2014 07:03

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The Vilnius Gediminas Technical University (VGTU) in Lithuania has just received two Cabri G2.

They will be used for CPL and Lithuanian Air Force training.

http://nsa31.casimages.com/img/2014/...1048867401.jpg




http://http://www.vgtu.lt/en/news/vg...icopter-pilots

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Peter-RB 21st Feb 2014 16:30

Hey HH

Whenever I see a picture of this helicopter I cannot but say : What a good shape and modern flow it seems to have, it seems almost ready to fly out of the picture at me.

Peter R-B
Lancashire

Dying to have a go in one! we have a spel cheaker but no Icons why!

EDML 21st Feb 2014 23:57

Starting a FI engine
 
I come from the world of fixed wing planes. As I almost only fly FI aircraft I do know that there are some that are really hard to start - especially when hot.

The Problem is not a cold start but hot starts after 10-15min. Especially when it is hot and in a congested engine bay you will have Problems with vapour bubbles that makes starting the engine very difficult.

Some fuel injected engines start very easily (the big Lycoming TIO540 in the Mooney TLS for example), others are hard to start - especially the IO360 used in the new C172S models is a beast when it comes to starting it hot.

When I started flying the G2 I did not like the idea of the carburated engine, however the automatic carburator heat works perfectly and is dependable in all weather conditions.


Marcus

HeliHenri 22nd Feb 2014 01:52

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Dying to have a go in one!
Hello Peter R-B,

It's just a matter of time ! :)

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stingerdinger 23rd Feb 2014 12:09

And another one for the UK...

Helicentre Aviation Places Order for Fifth Cabri G2 | Helihub - the Helicopter Industry Data Source

HeliHenri 27th Feb 2014 07:29

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Not a lot of news from the HAI in the forum so I have to do something ! ;)


"Yesterday was a banner day for French helicopter manufacturer Guimbal as it marked its entry to the U.S. helicopter market, with the delivery of its first Cabri G2 light single to Newberg, Ore.-based operator and training provider Precision Helicopters."

"Precision expects delivery of another G2 in June, with more to follow next year."


"Here at the show, Guimbal notched its second U.S. customer, Heritage Helicopter Services, which expects its first delivery in March 2015. According to chief pilot Curtis Spears, the Beaumont, Texas-based company will order up to six G2s, eventually changing over its fleet entirely to the French helicopter."

"Guimbal told AIN that his company has delivered 64 approximately $400,000 G2s to 32 operators worldwide and currently has a backlog of more than 100 rotorcraft. As the orders increase, he is striving to reduce order lead time to less than a year."




http://nsa20.casimages.com/img/2014/...3308934879.jpg



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Guimbal Makes U.S., Heli-Expo Debut | Aviation International News
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HeliHenri 28th Feb 2014 07:22

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first customer in South Africa :

Starlite’s International Aviation Training Academy was one of the launch customers who were welcomed by the Guimbal family, having purchased two of their latest Cabri G2 helicopters, with another six on order.

Starlite and Guimbal, more deals on the cards | Vertical Magazine - The Pulse of the Helicopter Industry

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nocarsgo 28th Feb 2014 19:28

First in North America
 
Vertical Magazine Shot

https://scontent-a-sjc.xx.fbcdn.net/...21343791_n.jpg

People were super excited that this is finally coming to the US to mix up the training industry. It got some serious attention. A lot of people were saying this was their favorite booth at Heli-Expo.

Precisions Facebook page: https://www.facebook.com/pages/Preci...29699817089197

www.flyprecision.com

HeliHenri 6th Mar 2014 09:42

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Bruno is holding talks in the US with several (very) large flight academies linked with O&G operators.

Maybe some more good news soon :ok:

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HeliHenri 9th Mar 2014 12:40

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Aerial works with the G2 by Frontier Helicopters ( NZ ) :






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John R81 10th Mar 2014 07:42

Saturday 8th March I saw G-ETWO in place at EBG Helicopters, Redhill. Flown back from the factory in 6 hrs with 1 fuel stop and landed with an hour's fuel remaining; 6000ft over the alps, 2-up with light luggage. Very impressive.

I understand CAA paperwork is expected to be completed this week, and 2x instructors are type-rated.

helihub 10th Mar 2014 17:04

There was a Luxemburg registered Cabri flying around in the UK on Sunday. Seemed to be a bit off-patch :ok:

HeliHenri 12th Mar 2014 09:45

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There was a Luxemburg registered Cabri flying around in the UK on Sunday. Seemed to be a bit off-patch :ok:
Hello Jeremy,
That's a good news :) because when it was French registered with a commercial operator, it was sleeping in a hangar most of the times :(

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