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-   -   Robinson R44 (https://www.pprune.org/rotorheads/189931-robinson-r44.html)

rotorboater 25th Sep 2006 15:28


Originally Posted by REDHOTCH0PPERPILOT (Post 2871453)
Done! Did I mention it has only been dynamically rolled once.

Did I mention I printed the money on my new colour photocopier!;)

bvgs 3rd Oct 2006 05:43

R44 to R44 clipper
 
Does anyone know if it would be permisable to retro fit pop-out floats on a R44? I know that this doesn't make it a clipper as there are various other things re tail rotor fin, position of battery, extra anti corrosion etc etc, however, would have felt more confident flying over water knowing that I had floats than without. I know that in the UK they're not certified anyway.....whether or not that would make a difference I don't know. Any comments would be great....oh and please lets not digress into single engines over water etc.

helicopter-redeye 3rd Oct 2006 07:07

You can make a Clipper into an IFR Trainer as it uses standard parts from the parts list.

So if the bottle, skid units, pipes & etc exist as parts in ther latest pink parts list it should just be a local workshop job to retrofit. You would want the tail fin wing as well.

You would need a new weights calculation as this would change the numbers permanently.

But what is a Clipper but a Raven I/II with a couple of extra bits on?


PS E&OE, not expert opinion, get approval from EASA, ask your engineers, etc

h-r;)



NB Clipper floats are not certified for commercial work, they still float privately...

sebdiazs 20th Nov 2006 15:40

Oil Level
 
Hello friend, i'm new on the list and I got a R44II (2004 s/n 10380) on September 2006. I have a doubt with the oil level if I filled up to 9 qt the first qt goes very fast and the level get stable arround 7 qt. It's that normal ?. Also always spill some oil after shoutdown, belive me that it's not confortable to put a piece of a newspaper under a "new machine"
Thanks and Regards.
Sebastian Diaz-Santelices
Private Pilot
Santiago, Chile
Baron B58 2001 TH-1971 - Robinson R44II 2004 S/N 10380
www.casablancawines.com/sebastian

8P-AUL 20th Nov 2006 15:59

Although the maximum oil quantity according to the book is 9 quarts, they tell you in the factory that it will always burn or blow down to seven.

Seven quarts is an acceptable level for flight.

rotorspin 20th Nov 2006 16:11

expect it to burn down to 7.5ish quarts and remain that way for 4-5 hours of flight before needing topping up. Just keep an eye on it, each machine it different, but this is the rule of thumb

the excess oil is blown out or burnt out to 7.5ish.....hence the oil on the floor after shutdown

Bluthyme 20th Nov 2006 20:00

Leaning Robbies
 

Originally Posted by Gaseous (Post 2156539)
Hi H,
I have written loads on mixture/leaning in the past.

Mixture adjustment is standard procedure on suitably equipped Enstroms and I always lean. Usually to 80-90 degrees lean of peak. Although this degree of leaning is outside the POH advisory limit, it it the best way to run a Lycoming. The injection system on my aircraft had to have a lot of work to get it to run smoothly at this mixture but it is now dead smooth to 100 degrees lean. If you go too far there is an increasing roughness and power loss way before the engine cuts dead - and yes I have done it.

On the contrary I don't feel happy running full rich. it wastes fuel, makes the engine run hot and clogs up the valve guides with crap. Cockpit carbon monoxide levels drop from 30 ppm to zero when lean. (I carry a digital detector) Fuel consumption drops from 14 to 10 usg/hour. A useful increase in range.

Running a carb Robbie lean is not possible as the mixture distribution is too poor. The injected Raven is ideal to run lean but unfortunately is not suitably equipped and you aren't going to get approval to modify it. You have no choice but to run full rich.

The risk with leaning is the brainstorm that makes you pull the knob when you want to go full rich. The silence is such a surprise and yes, I have done that as well, followed by an airborne restart.

Proper leaning and engine management of a piston heli is certainly possible but is not for the feint hearted or inexperienced.

Get it wrong and you will destroy your engine. Get it right and it turns the Lycoming into just about the most fuel efficient gasoline piston engine on the planet including modern automotive designs.

Quite a few Ppruners have flown with me and non have asked to get out when I do the lean bit.



At altitude it is standard procedure - on startup up, after warming up at 75% take up to 100% and lean to best rpm (and a little richer).

Gaseous 20th Nov 2006 21:26

I'm curious why my above post has been brought up from a year ago. For the full discussion see page 34 of this thread onwards.

Bluethyme you wrote

"At altitude it is standard procedure - on startup up, after warming up at 75% take up to 100% and lean to best rpm (and a little richer)."

That aint standard procedure in any helicopter I've ever flown - but I'm only rated in Robbies and Enstroms. Nobody in their right mind leans a standard Robbie and Enstrom SOP is to lean to <1650EGT or 100ROP(depending on model) - IN THE CRUISE. If you take off while leaned you WILL push the engine into detonation.

More relevant to current discussions. Enstroms also chuck the last quart out of the breather if filled to maximum. If I run between the minimum mark and half full I dont have to add any between changes.

HeliDriverNZ 21st Nov 2006 06:15

with regards the oil levels in the R44 we operate 2 of them and just run them on the 7 quart mark otherwise it just blows it all out the breather till it gets to this level so it's just wasting oil.

jemax 21st Nov 2006 17:02

New Question ref Max continuous vs Take off
 
A thought occured, to which I would be grateful for an answer,

I've not got the flight manual in front of me so excuse if the figures aren't 100% accutate.

Why is it that the difference in Max continuous and the 5min take off rating is 0.9" in a Beta 2 R22 and a Raven 2 R44 it is 2.9". My logic would have suggested that the two figures would be similar. Alternatively is the R44 significantly more downrated in the cruise?

I've asked around, but not yet got a conclusive answer I am happy with.

Thanks

Gaseous 21st Nov 2006 19:59

I would presume that the limit is temperature related, either oil or CH temp will go overlimit under test conditions if take off power is used for more than 5 minutes. In other applications these engines have different or no limits. The MAP which allows 5 minutes of operation will probably have been found experimentally on a fully instrumented engine. MCP keeps everything in limit under test conditions.

Any better theories anyone?

HFT 21st Nov 2006 21:33

Buying R44
 
Is it possible to buy a new R44 from the US and ship to another country say Aus and maintain full warranty. Web search shows that there is about 10k price difference advantage after o/s purchace and import. Thats allowing for all costs ins,freight,cofa,crates etc. thanks in advance

topendtorque 21st Nov 2006 22:01


Originally Posted by Gaseous (Post 2978754)
I would presume that the limit is temperature related, either oil or CH temp will go overlimit under test conditions if take off power is used for more than 5 minutes. In other applications these engines have different or no limits. The MAP which allows 5 minutes of operation will probably have been found experimentally on a fully instrumented engine. MCP keeps everything in limit under test conditions.

Any better theories anyone?

I'd only add a couple of points,
1) how fast do you really want to go in a R44, i think you'll find MC gives you an airspeed of a fairly quick clip,
and 2) after tooling around LL for quite some hours in '47 J models where a fully clothed engine compartment runs equally if not hotter than the 44 engine bay and where fuel vaporisation was a BIG risk, even without the standard method of no cowls, i'd suggest backing off a bit more in anything above 30 degrees ambient.

Where i work its been up to 45 and 46 c free air temp on several days of late, admittedly a bit unusual.

For sure the J models we used were turbo charged not just gravitry fed but i'd still think about it, any sort of a cough could herald fuel starvation.

We used to have as critical go / nogo, the seviceability of the aux furel pump on the J's. Thing is they blow up very frequently if left on, so we would operate on a critical CHT above which you could oft observe the fuel pressure starting to fluctuate about three or four seconds before the engine might stop. At the critical temp, aux pump - ON. The switch was right by your left index finger, amazing how observant one was of the CHT and FP.
Some turbo charged '47's were fitted with a fuel pressure sensor coupled to the aux pump which meant that the aux pump cut in if set on the auto position when fuel pressure went below a set pressure, usually 6 psi. Of course you must first set the engine driven puimp at 7 - 8 psi. It was a very good mod.
Fuel pressure below 4 psi can be injurious to heart and health.
cheers tet

Gaseous 21st Nov 2006 23:35

Hi tet.
I know some pilots who would do 200kts in a 44 if it would.:ooh:
I havent heard of fuel supply problems in flight in a 44. Anyone??
The 47 fuel system sound terrible. Things have got a bit better, fortunately.

Frank is conservative and likes to give limits. Good on him. Enstrom dont give any limits. They rely on the pilot watching the crap gauges so as not to cause meltdown. It doesnt always work.

3top 22nd Nov 2006 00:06

Hi all,

unless I had a CHT indicator for EVERY cylinder I'd rather stick with Robinson's manual.....

Oil-level is kept at 8 quarts - the 9th is blown out the breather-tube in no time.
Has anyone ever tried one of the oil-seperators on the market?
Any problem with STC or field installation?

Buy the R-44 from the local dealer! The small amout you save by buying in the US ( ...the dealer gives you some of his commission as a rebate, because he knows he will never see you again:))
However as good as the Robinson is, it still needs good maintenance. Your local dealer will not touch it unless you PAY for it! If it is a Robinson issue, Robinson will pay for it - while under warranty.
In my opinion the saved money doesn't warrant the possible trouble you are looking for....

3top
:cool:
... a little over 5k hrs in R44

jemax 22nd Nov 2006 07:10

Thx for thoughts ref MCP vs Take off, I do stick to limit's but just wondered the definitive answer before the inevitable question comes from a student.

Smart money is on CHT or oil temp limits at the mo then

topendtorque 22nd Nov 2006 12:16

Yes the turboed fuel system on the ’47 certainly took some understanding.

A so called redundancy system that was guaranteed to fail if left on and therefore would not be available to take over when / if the engine driven one failed. :confused:

I reckon that anyone who flies or allows continuance of that system without modding it to the auto pressure cut-in mode has got to be possessive of the dimmest intelligence imaginable, right up to and and including regulatory airworthiness types.

Jemax,
Best advice you can give them is, “your engine is your life – look after it.”

When you next chop the throttle whip out a card at the same time covering the MAP, OP and CHT instruments and challenge them to quote verbatim the last readings. No doubt all of your students would pass with flying colours, not forgetting at the same time to be doing all of the life-saving things that they are supposed to when you chopped the noise, EH?

It may help to adopt a waiting – staring at them pose at the same time, it may help them think that they were supposed to be learning something there.

Cheers tet

Hairyplane 14th Jun 2007 10:15

R44 Cyclic friction
 
Advice for a newbie please.

I now have 300 hours in my Raven 2.

I received the best possible training and customer service from Heli Air at Wellesbourne - no wonder they are the worlds leading Robinson dealer ( Ref: Rotor Torque magazine Summer 07).

A minor matter on the operation of the R44. I have spoken to many pilots about the use of the cyclic friction in flight and have yet to speak to anybody who applies it.

The Raven 2's controls are extremely light and sensitive. I find that in less than smooth air it is impossible to avoid 'pilot induced turbulence' through uncommanded cyclic control inputs, simply due to your own body being moved around.

I therefore routinely apply the collective friction after take-off and leave it set throughout. I also have no problem in leaving it set to some degree throughout the landing, and, again believe that this is of great benefit to me, especially if there is turbulent air around - often the case in confined areas etc.

So, a control lock on the ground only or a useful flight control?

Try it and see.

Hairyplane

moosp 14th Jun 2007 10:40

Hairy,

You will find that the Robbo community will split into two camps here, as it sometimes becomes contentious.

For me with a little over 500 hours on Robbos, and 18 instructors, (continuity training is my thing,) my distillation of the wisdom of these instructors is that careful use of the collective friction in cruise is useful and acceptable to them.

One occasion when it is useful is when the blade rigging is out. Then you will get either a rise (rare) or dropping of the collective when you take your hand off it. A TOUCH of friction will prevent this. Another case is when the carb heat control (not on your Raven II of course) has a friction drag with the collective control. i.e. when you pull carb heat the collective drops. A TOUCH of friction will control this.

You can see the problem. How much do you apply? I was taught to sit on on the ground with the engine off and play with the friction and the collective to learn how much is enough, and how much you can overcome if the engine fails in flight. The tricky thing is that each aircraft is different, but as the owner of one you should be easily able to learn the strength and position of the friction.

Most trainers seem to imply that any use of the cyclic friction in flight is likely to be detrimental to your life expectancy.

FWIW

O27PMR 14th Jun 2007 10:44

Hi Hairyplane

Sorry if I've misunderstood but you start off talking about cyclic friction and then switch to collective friction.

Are you saying you apply both in flight or are you just talking about the collective friction?

I wouldn't like to try flying with the cyclic friction applied:eek::eek::eek:

PR

BTW I do set the collective friction in flight once i'm happy:ok:

Twiddle 14th Jun 2007 10:52

I don't think he's talking about locking the cyclic friction fully on, just a tad to ease stick movements.

FH1100 Pilot 14th Jun 2007 14:18

Ah, we've been throught this before.

Many helicopter pilots like the loose, zero-feedback, "wet-noodle" feel of hydraulically assisted cyclics. They feel that any sort of friction at all detracts from their ability to control the ship smoothly, and that "no friction" allows them to make those necessary imperceptible control movements, especially in the hover. Maybe so.

But as the original poster declared, flying in rough air (yes, even hovering in rough air) can cause inintended cyclic movements, no matter how hard you try to prevent them. Think of it this way: *ANY* movement of the cyclic moves the swashplate a commensurate amount. If you move the cyclic 1/8th of an inch, the swashplate moves. Can 1/8th of an inch cause a diversion from "in-trim" flight? Of course!

Now, think of the pilots you know who use no friction at all. If you look at the cyclic in the hands of such pilots, it is almost constantly moving. Oh, the movements may be tiny, but it *is* moving, more than would appear to be "necessary." See it for yourself next time you fly!

My personal belief is that these tiny, unnecessary, unintended movements of the cyclic cause the overall ride quality to deteriorate. Pilots will argue this vehemently. All I can say is that I've spent a lot of time flying with other pilots over my 31-year career, and this is my observation. Personally, I use "some" friction on the cyclic where it is available.

Now, nobody in their right mind would suggest locking a flight control when the aircraft is in the air, or even applying so much friction that movement of the control is impeded. That would be lunacy. So I use just enough friction to give the stick some "break-out force" and drag. I use enough to keep the cyclic from moving if I loosen my grip or release it. I use it to dampen out unintended movements. Experimentation helps.

As an airplane pilot too, I know that flying an airplane with zero friction on the controls would be a difficult, fatiguing experience. (Try flying a simulator with no springs or any kind of dampening device on the primary control stick/wheel.) Why we helicopter pilots elect to do so when there is an alternative is beyond me. I've never understood it. But every pilot is different; to each his/her own.

My advice: If cyclic friction is available, use it.

scooter boy 14th Jun 2007 14:31

Hairyman,
I choose not to - for the simple reason that you never know when another whisk, a plank, a blimp, a bimbling engineless (radioless) plank, microplank or bloke with a parachute and big desk fan strapped to his back might violate your airspace and require a bit of rapid wrist action for avoidance.:E
I have had to do this on the odd occasion with far too little warning to go loosening frictions.

Most trips I do are 10-25 mins max so it doesn't get too tiring. I have 650 hrs (200 in R22 and 450 in R44 Clipper II)

SB

nimbostratus 14th Jun 2007 14:31

FH1100 Pilot;
Spot on!:D

Twiddle 14th Jun 2007 14:51

You're missing the point, nobody is suggesting cranking the friction on so tight you need to fight it, just a fraction to reduce the slop.

I've lifted a 44 with all the frictions on and it's no fun! (Actually, not true, for those watching it was a lot of fun apparently....:ugh:)

BHenderson 14th Jun 2007 16:29

An R44 with hydraulics will fly hands off if you give it the chance. There may be some unintended roll, but it stays level for at least 10 seconds.

scooter boy 14th Jun 2007 16:51

OK I'll try it on the way home tonight - if you don't hear from me again it's been nice talking to everyone here at PPRUNE and whatever you do don't turn up the cyclic friction.

Just kidding, I may tweak the knob a tad and see how I get on this evening (and I may adjust the friction also...).

An oscillation dampening tightness is all that is being proposed rather than a frozen stick rigidity.


SB

helicopter-redeye 14th Jun 2007 17:26

Depends on the #ship.

Personally I don't like cyclic friction on in anything.

Collective friction, every time.

But some 44's have a very tight Col friction setting that precludes a quick lowering.Personally I like it set so I can lower through the friction if needed but where it is quite tight to do so.

h-r (flown about 25 different R44's)

rotorfossil 14th Jun 2007 17:26

The problem of using cyclic friction on helicopters with powered controls but no artificial trim is that there is then a break out force; so once the cyclic is moved, it tends to be moved too far.
Collective friction ok in moderation so that turbulence doesn't disturb the setting, but probably better removed for the hover for same reasons as above.

fulldownauto 14th Jun 2007 18:07

I am 100% for using cyclic friction, esp. in the R44. Repeating what FH1000 said, in slightly bumpy air, the cyclic will move quite a bit, no matter how much the pilot tries to keep it still.

The way I apply cyclic friction is this: takeoff without friction, then after takeoff, move the cyclic slightly fore and aft (about an inch or so) while applying cyclic friction to the point where the resistance feels comfortable. Cyclic friction is of course, adjustable, there is not just 'on' and 'off'. I like to fly with quite a bit of friction, it does not impede my controlability of the helicopter at all. It makes flying in turbulence a lot more comfortable.

When using the friction, there should simply be an increase in the resistance when applying cyclic input, but there is no apparent 'break' force to move the cyclic.

Sometimes I land with the cyclic friction on, it feels only slightly different.
Even when flying the AS350, I like to use some cyclic friction on that ship to stabalize the cyclic.

All this not because I cannot control the cyclic, but again, with very sensitive hydraulic controls, it only takes a tiny amount of pressure to move the cyclic, and any movement that is not nessasary is a waste.

Hairyplane 15th Jun 2007 10:01

Cyclic friction
 
Sorry, the word 'collective' was an error in my post. In my machine the colective stays put unless a 'wider' pax moves around and gets his left cheek in the way.

The operation of the cyclic friction on my machine is delightfully linear - I just wind it up a little more as the ride gets rougher.

I dont experience breakout force at all, irrespective of the setting.

A smoother ride guaranteed with the friction applied.

Thanks a lot for such informative posts. Newbies like me need this type of feedback. Flying a heli after 31 years of fixed wing really focuses the mind!

All the best

Hairyplane

skysmurf 15th Jun 2007 15:09

How do Hairy Plane
 
I know its late in the day to add my 2 penneth to this thread but...

I made the mistake of touching the collective friction on my line check and the examiner went ballistic! ney F*$kin Berzzzzurk!

I only touched it as a " touch it so he can see your checking it..."!

ive only got a couple of hundred hours on R44 Raven 2, so will happily bow to the experienced pilots that do this for a living.

Regards
Skysmurf :hmm:

bvgs 15th Jun 2007 18:26

Hairy surely you mean his right cheek unless he's facing backwards:confused::confused:

Twiddle 15th Jun 2007 19:22

Nah, he means his left cheek with the collective left in........

Chukkablade 15th Jun 2007 19:23

PIC sits in the right seat on Helos bvgs, so hairy is spot on. It would be lardy lads left assslab thats shoving the lever down.

Edited to say we've all left the dual controls in before by accident. I know I have:{ And yes, its nearly bit ME on my harse before:(

bvgs 17th Jun 2007 10:35

I fly an R44 II so I know this, I just didn't think a low time heli pilot would allow a passenger anywhere near duals. They should be removed. With regard to cyclic friction, this device was NEVER intended for this purpose. Whether it works or not I think is irrelivant, it was only ever designed to lock the cyclic when the heli is on the ground as per Pilots Handbook.

My advice to you Hairy is to master the heli as you were taught, when you have several and I mean several hundred hours under your belt you may wish to experiment. Personally I wouldn't, I think Frank Robinson and his team know their machines better than anybody and what they say goes IMHO.

Safe flying.

rotors88 17th Jun 2007 10:57

As far as cyclic friction 'in flight' goes in the first instance, refer to the Flight Manual. Secondly if holding the cyclic of a hydraulic powered machine is so tiring then maybe some gym time would elevate the problem. And it aint no aeroplane. I fly 4-6 hours every day in a hydraulic boosted machine with legs up 3hrs if a get bored I sometimes swap hands or fly with my knees. I would never resort to applying friction to the cyclic in flight in the event of the unexpected, or an emergency, I little collective friction applied is different as in does not require the control finesse the cyclic does. :ooh:

HillerBee 17th Jun 2007 11:30

Totally agree with rotors88.

Cyclic friction was not designed for use in flight no matter how lightly applied, it personally freaks me out if anything is working against the freedom of the controls.

havick 17th Jun 2007 13:26

Does the Hydraulic R44 have cyclic trim like the Astro's?

If so, then keep in mind if you have a trim runaway, it will take you a lot longer to notice it and respond and accordingly isolate the relevant trims, possibly letting the trim to get to full deflection.

I agree with the previous posters, cyclic friction should not be used in flight.

3top 17th Jun 2007 14:26

Hi all,
I have about 900 hrs R22, 5000 hrs R44 (Astro, Clipper I, Raven I, Raven II, Clipper II). Training, Pilot checks, maintenance, tunaboat, external load, name it....

a) Astro - I don't use the friction there, but will switch off trim in turbulence.
Find a moment where the cylcic is not hunting in turbulence, switch off the trim and you have a neutral point that holds. If you forget to switch the trim back on, you will find out on approach :).

b) Hydraulics:
Depends - whether the machine is new or "run in":
At some point Robinson used rather tight rodends, that would need some 300 to 600 hours to loosen up. It was rather stiff, no friction needed. In a hover it was impossible to have a soft touch. I would have to apply a good grip to make the brake-out bump transparent. You could let go of the cyclic and it would not move at all.
Robinson changed the rodends on newer ships and they are rather nice now.
There is no or very little brake-out now, but a rather smooth drag on the controls. In a new helo you still can let go of the cyclic and it holds.
In well used hydraulic ships the rodends are loose (but no play, please!) and the cyclic becomes sensitive without a little friction - LITTLE friction, just enough to introduce a little drag, there is no brake-out force, as this came from the new rodends not the hydraulics. I am only refering to the rodends BEFORE the hydraulic cylinders.
No friction means the cyclic will fall wherever its own weight will push it if you let go of the cyclic...
As mentioned before, when the air gets rough a light helo like the Robinson will cause some pilot induced turbulence, allthough it is not half as bad as a EC120 or AS350.
Eurocopter instructors will insist to apply enough friction to keep the cyclic from moving in case it slips your hand. Personally I adjust it depending on weather, intended use, mood, what foot I got on the floor first that morning, whatever...

Gentleman, remember, for every pilot out there there will be a different set of rules, settings, preferences to apply.
Try it out and use it as you like, it also depends on the machine.
Those who insist, that friction is "dangerous", it is only dangerous if you lock it! In some occasions it may even prevent you from a spontaneous (panic) move - liek avoiding a bird you didn't see inthe first place...
No trim in the hydraulic ships!


Same for the collective in the Robinson.
Friction should be adjusted in a manner, that full friction application still lets you lower and raise it - never fully locked!! If you need more friction than that, put it in the shop!!
Also on the hydraulic collective, there should be NEVER a climbing collective!
(Actually in the electric trim one either....)
A decending ("heavy") collective should be only very little, basically induced only by its own weight (collective lever) with all the friction off.
If it is really heavy, into the shop!
It is may be some tedious work on the electric trim helo to get the collective right, but this is a "good" indication of bad rigging if the collective is excessivly heavy.

Hope it helps!
3top :cool:


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