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Robinson R44

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Robinson R44

Old 19th Feb 2009, 18:12
  #1141 (permalink)  
 
Join Date: Oct 2003
Location: Michigan USA
Posts: 58
Yes, like Mutt said, it would be a clearance problem with the blade to tail. It's only an issue to new pilots IMO. Once you get used to flying it, it's like flying anything else so why bother even trying to change the design?
You said you instruct "now in the 44 as well," which implies that it is a fairly new machine to you? You'll notice the more you fly it the less it'll be an issue and as you see your students progress, you'll see it's of little issue to them as well... especially if they come from the 22 into the 44.
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Old 19th Feb 2009, 18:44
  #1142 (permalink)  
 
Join Date: Mar 2006
Location: Aust
Posts: 88
The best way to stop a 44 swaying on landing is to ease up on the pedals the swaying will disapear
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Old 19th Feb 2009, 18:46
  #1143 (permalink)  
 
Join Date: Mar 2006
Location: Aust
Posts: 88
and cross winds from the left are the most difficult
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Old 19th Feb 2009, 20:07
  #1144 (permalink)  
 
Join Date: Oct 2003
Location: USA
Posts: 123
I am fairly new to the R44 but with over 5,000 hours I am not new to helicopters. I agree that the pedals start an oscillation but I am still curious as to why it was designed with such a small yoke and long mast. Any ideas?
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Old 19th Feb 2009, 20:11
  #1145 (permalink)  
TRC
 
Join Date: Aug 2006
Location: Wiltshire, UK
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...why it was designed with such a small yoke and long mast. Any ideas
Because it's a Robinson - designed by Walt Disney.

I'm out of here.....
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Old 19th Feb 2009, 20:43
  #1146 (permalink)  
 
Join Date: Mar 2008
Location: A land not far from here.
Posts: 68
Sarcasm.... Not very nice....

Why the long mast you ask???

Lets just say this, i'm sure franky has designed it to its best capabilties!! Hence, looks don't really come into effect... If the aerodynamics work... Then dont f*** em up, and leave it as is... Thats probably how the design came about....!

If you think thats bad, picture the look o the due R66!!??

The pendulum moment doesn't come across as a problem, more of a factor to adapt to i think... the worst problem ive seen with the robbys (R22 mostly) is the tail boom, never had a problem with it myself, but ive seen them clobbered a couple of times, not nice at all!!

Luckily helis on the ground at time! Tail booms sent back to california for repair.... Yeowser...
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Old 19th Feb 2009, 20:44
  #1147 (permalink)  
 
Join Date: Dec 2006
Location: Denmark
Age: 69
Posts: 2
R 44 in the envelope

I have one R 44 Clipper II in a JAR-OPS 3 setup in Denmark sinse aug 05 Factory new delivery. Short intro: S-61 Royal Danish Air force SAR aprox. 500 hours and amongst others some 50 "life saving missions" in the North Sea, typical november, lowpressure 960 or less, night, iceing conditions, rain sleet or snow up to 100 knot windspeeds, high waves, what have you.
I was 22 (1972) and now I am too old for any of that hot shit.
Comming back to the Robinson 44 - I have done some 1500 flights over 3 years and I say "I don't like it, I love it ! "
The R-44 is one friendly thrustworthy ship to operate. As with any other pease of technology, if you operate in accordance with the design philosophy and applicable limitations, she will take you there and back with a great deal of confidence in your stomace.
If you take a Ferrari through a long high speed curve along the lee side of a wood in fall, and fly off the road due to slippery leaves on the road, don't blame the car ...
Hope this was not to direct, it is just that my R-44 and I are pals ...
Fly safely youall ...
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Old 19th Feb 2009, 21:56
  #1148 (permalink)  
 
Join Date: Nov 2008
Location: UK
Age: 61
Posts: 905
I understand you can reduce the pendulum tick tock in the hover by gently stirring the stick in a small circular motion.
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Old 19th Feb 2009, 22:22
  #1149 (permalink)  
 
Join Date: Mar 2006
Location: On the move...
Age: 54
Posts: 359
I thought the pendulum was from stirring the pot.
The Robinsons are very sensitive. The aircraft will only move because you make it!
IF you came from a B47 and your handling skills were a bit 'sloppy' then you will be moving about in the R44. I don't mean this as a criticism, just an observation. I went from an MD500 to a robbie and my handling skills were lousy. Simply being too heavy on the controls.
Be really light and don't move and it will stay where you want it to.
Try jumping to and from an R22 to a B206 and back on the same day, same handling skill needed.
As one of my chief pilots asked me, are you flying it or is it flying you?
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Old 19th Feb 2009, 23:34
  #1150 (permalink)  
 
Join Date: Jun 2003
Location: PUDBY
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My instructor (15000+ hrs of heli time) claims that the R44 is the squirreliest heli on landing that he has come across - specifically its tendency to sway around just when you thought you were about to land. Speaking from the height of my 16 hrs or so of heli time, it seems to be something you get on top of fairly quickly. I've noticed that my instructor does "stir the stick" noticeably during touchdown. (I can't say what I do, at my level if I started trying to observe myself at the moment of touchdown it would certainly go wrong.)

n5296s
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Old 20th Feb 2009, 17:31
  #1151 (permalink)  
 
Join Date: Oct 2003
Location: USA
Posts: 123
I was told to stir the cyclic to reduce the pendulum effect and I think it works to some degree. However, I come back to the original question: why not make the yoke larger and reduce the length of the mast and therefore the pendulum effect? On the Robinson safety course they said the mast length was to help with C of G but I can't see that being right.
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Old 20th Feb 2009, 18:05
  #1152 (permalink)  
 
Join Date: Nov 2001
Location: Norfolk
Age: 80
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In a two blade gymbal head rotor as on the R44, the wider the potential C of G range, the taller the mast has to be to retain sufficient fore and aft cyclic control for the extremes of Vne in forward flight and demonstrated downwind capability or rearwards movement in the hover.
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Old 17th Mar 2009, 09:50
  #1153 (permalink)  
 
Join Date: Feb 2008
Location: midlands
Age: 59
Posts: 61
Overspeed

I have been asked some questions on MR overspeed by a non-forumite ( foreigner/ poor English!). I don't feel qualifed to fully answer them, hence my post to pick the brains of you experts out there -

1. My understanding is that the spindle bearings suffer rapid wear if the thing has suffered an overspeed. If an aircraft has done, say 50 hours since an overspeed and seems otherwise perfectly normal - is it likely that the damage will be restricted purely to the spindle bearings?
2. Would you always change both bearings if one is found to be damaged and the other looks OK?
3. If the thing has suffered a MR overspeed, is there an immediate check that can be carried out? I would guess that's the time to sell a machine - 'oops, somebody elses problem'...
4. How much are the bearings from Robinsons and how many hours does the job take?

Thanks a lot.

JB
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Old 20th Mar 2009, 12:06
  #1154 (permalink)  
 
Join Date: Nov 2006
Location: UK
Posts: 444
1. My understanding is that the spindle bearings suffer rapid wear if the thing has suffered an overspeed. If an aircraft has done, say 50 hours since an overspeed and seems otherwise perfectly normal - is it likely that the damage will be restricted purely to the spindle bearings?
2. Would you always change both bearings if one is found to be damaged and the other looks OK?
3. If the thing has suffered a MR overspeed, is there an immediate check that can be carried out? I would guess that's the time to sell a machine - 'oops, somebody elses problem'...
4. How much are the bearings from Robinsons and how many hours does the job take?
1. 30hrs will show-up an overspeed. Damage depends on amount of overspeed. Generally it's just the bearings.

2. Would make some sort of sense, since both will have been oversped. Are you a pilot ?

3. Yes. Lift blades off. Takes about 2hrs with 2/3 engineers. Selling-on to a sensible customer would involve an inspection by an engineer - and the first abuse they look for is MR and engine overspeeds.

4. Suggest you call a reliable, busy maintenance company like Heli Air and get the latest prices - parts subject to dollar flucs.
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Old 20th Mar 2009, 12:31
  #1155 (permalink)  
 
Join Date: Feb 2005
Location: Australia
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Suggest you call a reliable, busy maintenance company like Heli Air and get the latest prices - parts subject to dollar flucs.
Do suggest also that you inform maintenance company how much of an overspeed that you or someone you know has had.

They will have an interesting list of costs of repair which may resemble a graph , like Y=Xcubed or maybe Y=Xto the power 4.

I bet you whatever it is it will be cheaper than someones' life if you or someone else misrepresents the true data.
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Old 20th Mar 2009, 12:47
  #1156 (permalink)  
Red On, Green On
 
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I would guess that's the time to sell a machine - 'oops, somebody elses problem'...
I expect this when buying secondhand cars, but a buyer of an R44 would hope for more integrity from a seller who knows of such a potential issue.
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Old 20th Mar 2009, 14:36
  #1157 (permalink)  
 
Join Date: Feb 2008
Location: midlands
Age: 59
Posts: 61
MR overspeed

Thanks for the reply, I was beginning to think that the R44 Corner was going a bit stale hence my fresh post.

You describe an ideal world. If only others were as responsible as you and I.

Its also possible i guess for a new pilot to inadvertantly overspeed the MR and actually not fully realise what they have done.

JB
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Old 20th Mar 2009, 17:40
  #1158 (permalink)  
 
Join Date: Nov 2006
Location: UK
Posts: 444
Its also possible i guess for a new pilot to inadvertantly overspeed the MR and actually not fully realise what they have done.
Mmmmmm. This is where we may differ. Even without monitoring the instruments, a properly-trained pilot should hear MR speed climb. The noise change is there - you just have to listen for it.

As most MR overspeeds are done whilst descending, they should be easily avoided.

Similarly, there are a lot of engine overspeeds at start-up. Simply avoided by checking the throttle is closed before pushing the button. If that means you have to look down at the arrow on the collective to remind yourself, then do so. It's a one-second check that saves about 20,000.
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Old 20th Mar 2009, 18:54
  #1159 (permalink)  
 
Join Date: Feb 2008
Location: midlands
Age: 59
Posts: 61
MR overspeed

Hi Jim,

An overspeed on start-up is a nightmare scenario and, I agree, easily done. I know of a school with a mandatory customer insurance policy - two hundred quid a year AFAIAA - on their self-fly hire fleet.

Do you share the advice of some that if you need to crack the throttle open to start a hot engine its best to switch the governor off as an additional safeguard?

So easy to overspeed the MR during Auto practice, especially in the turns.

J
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Old 20th Mar 2009, 20:15
  #1160 (permalink)  
 
Join Date: Jul 2007
Location: England
Posts: 197
Out of curirosity, and as I dont have access to the book right now, what percentage of rrpm does it have to exceed to be classed as an overspeed?
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