Two seat helicopter build.

Incidentally, you may want to rethink the main rotor lead/lag adjustment mechanism. It's probably the only thing I don't like about my RW.

I have been putting some thought into that rotor head. I think I like it so much because of it's simplicity, and making a clone head would not be too hard. The only part that would prove to be a good challenge would be those two 2.5deg holes for the feathering shafts. I would probably send the head out to a more capable shop for that part. My default line for businesses when they ask what its for, I always say it's for a "hovercraft" :rolleyes:. that way they don't loose their minds and boot me out the door.

The lead-lag issue is still one I have not figured out. I like the simplicity and that makes me not want to start articulating the head too much. I really don't want to begin putting rubber bumpers and things like that up there that absorb and release energy for lead-lag. It may be good to hinge that axis on a bolt, but it would need to be a hefty bolt and with the blade straps being used, I am not exactly sure how to do it. Last time I calculated it, each blade would pull about 16,000 lbs on the head at 520rpm.
 
Interesting project indeed.

I've been flying my Rotorway Exec 162F for nearly 18 years.

Curious what main blades you are using? As you know, the Rotorway blades are non-symetrical and you can't simply turn them upside down and run them "backwards".

Incidentally, you may want to rethink the main rotor lead/lag adjustment mechanism. It's probably the only thing I don't like about my RW.

Would you happen to know how I could get a hold of the drawings for the rotor head? I have PDF files of the Rotorway build manual, but I noticed that they are not comprehensive manuals. There is almost no information about the particulars of the head. All of the information I was able to get came from my AP school happening to have a donated Rotorway rotting away in their building. I don't have the full picture though.
 
Yeah... that oil cooler looks like it will keep the engine cool... I would definitely have an oil temp gauge though... :)
And I like your idea of an extra qt or two of oil in the system.

On the rotor head... that is obviously the magic part that keeps you from falling from the air like a rock... :blue:
I think I would consider finding a used low hour one from the factory... rather than attempting to make one in your machine shop...
I have made rotor heads for gyro's... prefer the 'sport-copter' design...
I decided it was just too risky... better to let the pro's build that crucial part... :)
After all... in experimental aviation... one only gets 'one' accident... :eek:
 
I think I would consider finding a used low hour one from the factory

I can't argue with that wisdom. :cool 2:. The one real nice thing about that head is that it uses those elastomers. I planned to buy those from Rotorway. I believe they are around $500 a piece. The only other option I know of would be to use matched angular contact bearings that are stackable. Besides that getting expensive real fast, the other issue is brinelling on the bearing surfaces from constant minimum feathering movement. The elastomers seemed like the best and easiest option to deal with.
 
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A dry sump oiling system could be beneficial, especially from a cooling, and oil volume standpoint, but would add quite a bit of complexity/expense to the equation.

Thanks for the link :). I checked out the site and it appears that they do not have anything off the shelf that I can use for the engine. The EG33 has a 17 bolt hole pattern for the oil pan.

I am not real familiar with a dry sump system, but it would appear to add weight and complexity to the engine. I would feel that going that route may be something to try after the helicopter is known to fly so that variable is not introduced along with all the other uncertainties.

My weight goal will be to try and keep the helicopter under 850lbs dry weight.
 
Jake, you should try to keep your oil temp above 212 deg., to boil off condensation in the crankcase and prevent the build up of acids in your oil. Mike
 
Thanks for the link :). I checked out the site and it appears that they do not have anything off the shelf that I can use for the engine. The EG33 has a 17 bolt hole pattern for the oil pan.

I am not real familiar with a dry sump system, but it would appear to add weight and complexity to the engine. I would feel that going that route may be something to try after the helicopter is known to fly so that variable is not introduced along with all the other uncertainties.

My weight goal will be to try and keep the helicopter under 850lbs dry weight.

Jake:
If you look at a lot of the LSA's with the Rotax engines, I believe that most of them are of dry sump configuration.

I should ask my nephew about the high performance end of things. They run 540 cubic inch engines at around 9500 rpm with a pretty decent size blower on it. 2000hp roughly, but he only has to run it for 30 seconds. LOL

Also, have you flown a heli before? ;)
 
Also, have you flown a heli before?

Yep, I sure have :). Got my license for it. Pretty much my calling in life and if the market outlook for helicopter pilot was not so bleak, I would have gone all the way to CFII. Instead, I settled for making it a hobby and going for aerospace engineering. That way I can feel good about myself designing a bolt for the executives that make all the money :rolleyes:.

:D:D:D HELICOPTERS:D:D:D
 
dry sump configuration

With weight being such an issue with this thing, I don't know if dry sump would really be that much of a benefit. Heat can be mitigated through the use of a good sized cooler and volume can be added just as easily and I would be surprised If I ever pull 3g in that rig. I wont be doing any "hold my beer" maneuvers because that's a good way to die.

I don't know, I guess I feel that dry sump is way overkill for what I am doing. I am asking the engine to run 165hp all day long. That's a fair bit of continuous power for 3.3L, but I would have been worse off with the 4 cylinder variants.

I plan to run my engine stock at first and see what happens. The EG33 had 230hp from the factory at around 5400rpm. Now, I highly doubt that engine could ever run that for any real duration (in the car engine bay with OEM plumbing) because of lots of heat being generated, but it's good to know the limits.

Before I make the 4 belt crank sheave I will need to take the completed engine in turn key state and put it on a engine dyno. I wish I could find a stock dyno map of this engine, but I was unsuccessful. So, I will have to make one so I can see what RPM can produce my 165HP. My assumption is that 4000 may just be good enough to get me there, but I am not certain. That's at 74% of the rpm range. Probably pretty close to what that engine used to have to work with when accelerating a car through the on ramp.
 
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Jake, you should try to keep your oil temp above 212 deg., to boil off condensation in the crankcase and prevent the build up of acids in your oil.

Mike, I had never even thought of that :eek 2:. I wonder what Amsoil requires for minimum and maximum temps. I had planned to use "Dominator 10W-30 Racing Oil".
 
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