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RAM EA81 airplane part


Phizinza
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Look at what I'm on about here To save USMB some band width

 

I saw this on the RAM engines site. Thought, maybe a crawler gear setup for a offroad subie? Just plug the output on a subie clutch and gearbox. And you have half'd your end gear ratio? Also good for lifted rigs? As the output is lower then the imput. Probably the only draw back, $XXX? Have we covered this option on USMB before? Just thought I'd share this with all, because all those posts Scott posted.

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wow! that sounds great! .... errr what IS it? *edit* ok I got it now ... it's a gearbox ... how would you put this on with your reg tranny?

 

I love the sound of cuting the gear ratio in half, but I am confused as too how exactly it attaches... and at my current set-up with a weber'd ea81, I no longer have a 4th or 5th gear ... I have two over-drives! :-p so, I don't think that cutting my gear ratio in half would hurt me much ... how much is it? might it be easier than adding on a set of nissan T-cases?

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That RAM redrive is pretty cool, nicer thank most I've seen. Would be sweet to slip one between engine and trans. Maybe NSI at Arlington has an EA81 redrive unit laying around they'd sell for cheap? Probably not...if it flies it costs. But maybe they get too worn and tired to fly, but still good enough for land use? Here's a couple of lists of aircraft conversion vendors incase anyone wants to troll for redrives. Powerplants

Engine Accessories

If I was rollin in cash, I'd like to put one of those Klune V reduction boxes between the trans and divorced t/c. Pics and article here: Klune V

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just a thought does this airplane redrive reverse the direction , or keep it normal ?

 

Good point. Heres more info about it http://www.autoflight.co.nz

 

I'm going to go have a look now.

 

As for fitting it, what I would do is bolt it to the engine,probably put the flywheel and clutch on the out put side of it (keeping it in the trans side of the flywheel housing. And if I were really surius, I'd get a engine side flywheel casing and build the "gearbox" into it. I just asked the NZ autoflight guys how much it would cost plus shipping to AUS. I asked RAM, but they told me to save some money and goto the autoflight site itself.

 

Time to go find out if it stuffs up the direction.

 

On a side note, I'm lucky to be on my computer right now, last night my hard drive turned itself off while in windows. Then the computer crashed, I had to do a complete reinstall. Lost all my emails and stuff, but cos I keep all my important files on another partition I still have most of it. Just took me 5 hours last nigh fixing this damn thing :( Glad I know quite a bit about computers.

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Thinking of a Sube application is cool.

I would first find out about the reverse drive... but then:

Consider that these assemblies are designed for a propeller cutting through air. Its case, bearings and gears may not be up to the load that will exist between an engine and pavement, let alone the variations of transmission or tires. It may completely blow apart in 1st gear - dunno??

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Thinking of a Sube application is cool.

I would first find out about the reverse drive... but then:

Consider that these assemblies are designed for a propeller cutting through air. Its case, bearings and gears may not be up to the load that will exist between an engine and pavement, let alone the variations of transmission or tires. It may completely blow apart in 1st gear - dunno??

At a propeller's designed speed, air is approaching its compressability limits... tires on pavement might provide LESS load and stress...

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tires on pavement might provide LESS load and stress...

Yes, but on-road gives more shock stress. And you are always letting out the clutch, where as this device in a plane would only have to start up once, and then its smooth running from there. So the question is, will it take shock? Something to ask the manufactures. It has to be tough and reliable to go in a plane. But who knows.

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  • 1 month later...

yeah its been discussed before... but that does bring a couple interesting ideas to mind... possible rear engine 4x4? dual engine rig? take an extra engine and mount it on the hood or in the back where the hatch used to be and put a prop on it? kind of an interesting idea actually.. would be waaay heavy but...

post-16176-136027605846_thumb.jpg

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for these redrive systems, maybe there are other vendors or fabricators that could design what you guys are looking for that isn't intended for flying ($$$$). there are industrial, farm and other gear driven applications that might be more economical. has to be someone out there that can make something like this for the trail.

 

on to more boring and off topicing stuff

 

would the air have time to compress before it is displaced off to the side of the blade?

 

air isn't "deflected" by the curvature of the blade. it locally speeds up across the blade (or wing - cross section of a wing and propellor are similar) creating a pressure difference between the front and back (or top and bottom of a wing) which creates the thrust (or lift). if it were only

displaced or redirected so to speak it wouldn't do anything. this is cool ....imagine squeezing your garden hose to make it come out faster (air and water are both fluids to engineers). picture the "humps" in the wing of an airplace (similar design to a propellor) as your finger on the garden hose. at the very tip of the wing you're not really pressing the hose much. then towards the middle "the hump" is where you're pressing hard and the water is coming out much faster. picture an imaginary wall 1 foot above the wing, the air is confined between the wing and this wall as it travels front to back speeding up just like your garden hose as you squeeze it. as velocity increases pressure must decrease (physics, etc). so the velocity increases and pressure decreases on the top. but the bottom of the wing is flat so the pressure remains about the same....so the pressure decrease on the top means the bottom is at a higher pressure and that creates lift. that simple (well, not really) principle is what lifts airplanes weighing in at 100's of thousands of pounds. crazy huh?

 

in terms of compressing the air into a smaller area yes, but in terms of compressing the density i don't think that has much impact in terms of drag on these applications. in this instance drag is typically regarded as a function of the boundary layer seperation which does increase with increasing density (compressibility so to speak), but that is one of a number of factors in the Reynolds number which is the value of interest in most aerodynamic analysis. i would guess props are designed for limited boundary layer separation and any that did occur would be isolated to the tip (highest localized speeds).

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"....so the pressure decrease on the top means the bottom is at a higher pressure and that creates lift. that simple (well, not really) principle is what lifts airplanes weighing in at 100's of thousands of pounds ...."

 

Or, to restate the concept in it's simplest state, "the wind don't BLOW, it SUCKS.

 

Also true of weather my friends.

 

Admirable explanation grossgary, but my version is easier to rremember for the FAA written.

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if you mounted a redrive of this sort, their would be no tranny.we would want an adapter redrive .kinda like an "inbetween" gearbox .they make those for combines,tractor pto's ....things like that.the hard part is finding a case that fits.would have to make one.

 

 

we could really make our own transfer cases.for mount inbetween the tranny and engine.a bolt on affair.all we need is a reduction gearing .

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  • 2 months later...

uhhh... rear engine might be cool

 

there was a job opening for a PTO counter person at six states, truck/driveline shop, they do a lot of other stuff there too dealing with almost anything in the drivetrain from the clutch/transmission to the hubs. would have been able to get a LOT of information for us... maybe they're still taking applications. being able to get parts at COST, and all the differant parts they can get in or even make, and having a machine shop, and all the incredible number of books and catalogs... ughhh I wish I had applied

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