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  #1  
Old 12-19-2005, 01:43 PM
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neverquit neverquit is offline
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Default Twin Powered EZ

Pulled this out of Rough River 2003 just for fun. Anyone know about this beast?
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  #2  
Old 12-19-2005, 02:18 PM
Joe Berki Joe Berki is offline
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Yes, he removed the two engines and went to a O360. It burned more fuel and was slower with the two engines.

Joe Berki
Limo EZ
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  #3  
Old 12-19-2005, 02:34 PM
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Quote:
Originally Posted by Joe Berki
Yes, he removed the two engines and went to a O360. It burned more fuel and was slower with the two engines.

Joe Berki
Limo EZ
sounds like a twinn to me
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Old 12-20-2005, 03:51 PM
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But after having an engine without power for about 2sec @ 600ft agl in IMC during my last IFR lesson, I'm beginning to see the benefits of having a spare engine
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  #5  
Old 12-20-2005, 04:38 PM
ShaleDC ShaleDC is offline
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I seem to have read something to the effect that the Twin-EZ couldn't climb or maintain altitude w/only one engine, which defeats the purpose of having 2 engines.

If true, that's not surprising, since the Twin-EZ pictures show that he used fixed pitch props . Certified twins use variable pitch, feathering props, so that if an engine (or prop) fails, it feathers to reduce asymetric drag. Without feathering props, a twin is MORE dangerous than a single, IMHO.

Props or underpowered engines aside, it seems like overkill for a bird as small as a long-ez. A velocity XL might benifit more from twin engines, and properly designed, it could be nice to have the safety margin when carying your family of five on board. (I've seen pictures online of a model of a twin-Velocity. Looked pretty cool!)
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  #6  
Old 12-20-2005, 04:51 PM
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Quote:
Without feathering props, a twin is MORE dangerous than a single, IMHO
I suppose it DOUBLES your chances of an engine failure!
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  #7  
Old 08-09-2006, 05:29 PM
SteveWrightNZ SteveWrightNZ is offline
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Quote:
Originally Posted by ShaleDC
I seem to have read something to the effect that the Twin-EZ couldn't climb or maintain altitude w/only one engine [...] he used fixed pitch props. [...] Without feathering props, a twin is MORE dangerous than a single (*windmilling prop)
warning - contains math !
I still like this idea, but obviously that windmilling prop has to be feathered, or *stopped*. What about a simple exhaust brake ? To stop the prop, kill the ignition or fuel or both, open the throttle, and close the exhaust brake. The engine should stop dead in its tracks in less than a second.. certainly does on diesels.

If someone attempted to stop the wrong prop, likely it would fart very loudly also. Dunno.

Would ME rated people share - what is the performance hit from a windmilling prop ? Conceivably, would a descending ME aircraft with a windmilling prop, turn into a climbing aircraft with a stopped prop ?

If I understand correctly, with conventional GA twins, the risk of engine failure is much less by a factor of more than just two ? Doesnt the risk muliply and not simply add ? TWO engines statistically has double the rate of having problems, but 1 TENTH of the rate of that occurring simultaneously ?? Who knows about the math on this ?

But in a sitation where if one engine fails, but also kills the second engine (windmilling prop scenario) arent we actually worse-off by a factor of TWO over a single ?

nb. [...] = snippage, (*comment) = my comment.

S
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