Canard Community Forum  

Go Back   Canard Community Forum > Firewall Backward and Forward
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 12-19-2005, 01:43 PM
neverquit's Avatar
neverquit neverquit is offline
G.Norman
 
Join Date: Sep 2004
Location: Lathrup Village, MI
Posts: 1,481
Default Twin Powered EZ

Pulled this out of Rough River 2003 just for fun. Anyone know about this beast?
Attached Thumbnails
Click image for larger version

Name:	twin-EZ2.jpg
Views:	126
Size:	8.8 KB
ID:	1698  Click image for larger version

Name:	twin-EZ.jpg
Views:	133
Size:	7.1 KB
ID:	1699  Click image for larger version

Name:	twin-EZ3.jpg
Views:	165
Size:	75.7 KB
ID:	1700  
Reply With Quote
  #2  
Old 12-19-2005, 02:18 PM
Joe Berki Joe Berki is offline
Member
 
Join Date: Apr 2004
Location: Elyria,Ohio @LPR
Posts: 77
Default

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
Reply With Quote
  #3  
Old 12-19-2005, 02:34 PM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

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
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
  #4  
Old 12-20-2005, 03:51 PM
Control's Avatar
Control Control is offline
Member
 
Join Date: Sep 2004
Location: Stockholm, Sweden
Posts: 131
Default

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
Reply With Quote
  #5  
Old 12-20-2005, 04:38 PM
ShaleDC ShaleDC is offline
Member
 
Join Date: May 2004
Location: Alexandria, VA
Posts: 673
Default

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!)
__________________
Plans #000

Redesigned 4-place canard.
500+ hrs into prototype build, Start Oct. 1, 05

(also build a MkIV fuselage, w/plans #1279)
Reply With Quote
  #6  
Old 12-20-2005, 04:51 PM
Spodman's Avatar
Spodman Spodman is offline
Wannabe - with plans
 
Join Date: May 2004
Location: Victoria, Australia
Posts: 486
Default

Quote:
Without feathering props, a twin is MORE dangerous than a single, IMHO
I suppose it DOUBLES your chances of an engine failure!
__________________
Mark Spedding - the Spodman
Darraweit Guim, Australia
Theoretical Cozy IV 1331 - Celebrating 2 years of not building anything
Reply With Quote
  #7  
Old 12-20-2005, 05:12 PM
JonC's Avatar
JonC JonC is offline
LEz - N555LE Q - N555QA
 
Join Date: Jul 2004
Location: Mountain View, CA
Posts: 997
Default

Quote:
Originally Posted by Spodman
I suppose it DOUBLES your chances of an engine failure!
Ok, you guys are just wearing that quote out. Oddly enough I always seem to hear it from people who fly singles and not from guys who fly twins. Twins are a larger workload than a single engine aircraft, and yes a twin does have double the equipment to fail of a single... however a twin will also keep you in the air if you lose half of the equipment, if you know how, and practice to fly it with a single engine. As with any complicated airplane they are inherently more dangerous to fly than a simple airplane if you do not know what you are doing.

Personally, I'd take a Cessna 303 with a failed, feathered engine to a LongEZ with no engine any day. I know the 303 is going to make it to the next airport as long as that other engine keeps running, plus if I absolutely, positively had no other choice I could do a go-around in the 303, not so in the single.

Lets face it... with a well designed twin, and the knowledge and experience of how to use it you will make it to the next airport. If you do not have the experience or knowledge of how to, you will make it to the scene of the accident, just the same as you would in a single. So lets get off this idea that twins are more dangerous and move on.

And yes, this is a sore point with me.
__________________
~Nathan
Reply With Quote
  #8  
Old 12-20-2005, 06:11 PM
neverquit's Avatar
neverquit neverquit is offline
G.Norman
 
Join Date: Sep 2004
Location: Lathrup Village, MI
Posts: 1,481
Default

Have to side with you on that one Nathan. There's some very good twins out there and some real dangerous ones. I might say the twin EZ is slower and obviously more expensive to run but that might change with tweaking. Heck, the guys got fixed pitch props! I think it's just great to see what guys are trying out with canard planes. Can't wait to see what comes in the future.
Reply With Quote
  #9  
Old 12-20-2005, 07:02 PM
satch satch is offline
Member
 
Join Date: Aug 2005
Location: SWFL
Posts: 76
Default

Just to follow up on JonC's comments ... when is the last time you heard of an off-field landing in a twin?

The downside is, of course, that when you do hear of one it's usually at the bottom of a crater or inverted. More often than not, I'd wager that while a contributing factor was engine out, the causal factor was (gasp) pilot error.

Here's how it goes:
- pilot looses engine,
- pilot looses SA at critical time,
- pilot reefs nose, wraps it up, or slams on remaining throttle
- plane stalls or otherwise out of control (not enough power, too much AOA, too much power, too much yaw or some combination of all)
- plane hits ground w/ steep decent angle or inverted.
- everyone says, should've been a single

Tirade over. I want a twin.
Reply With Quote
  #10  
Old 12-20-2005, 08:34 PM
MarbleTurtle's Avatar
MarbleTurtle MarbleTurtle is offline
Member
 
Join Date: Apr 2004
Location: Dalton, GA.
Posts: 1,344
Default

Anyone have a picture of that twin-Velocity XL 5?
__________________
Past performance is no guarantee of future results.
Reply With Quote
  #11  
Old 12-20-2005, 10:38 PM
argoldman argoldman is offline
Rich
 
Join Date: Dec 2004
Location: chicago area
Posts: 481
Default

Quote:
Originally Posted by satch
Just to follow up on JonC's comments ... when is the last time you heard of an off-field landing in a twin?

The downside is, of course, that when you do hear of one it's usually at the bottom of a crater or inverted. More often than not, I'd wager that while a contributing factor was engine out, the causal factor was (gasp) pilot error.

Here's how it goes:
- pilot looses engine,
- pilot looses SA at critical time,
- pilot reefs nose, wraps it up, or slams on remaining throttle
- plane stalls or otherwise out of control (not enough power, too much AOA, too much power, too much yaw or some combination of all)
- plane hits ground w/ steep decent angle or inverted.
- everyone says, should've been a single

Tirade over. I want a twin.
Satch,

What you are missing in the above scenerio is the most important concept with a twin (center line thrust not withstanding). Whe you loose an engine, the asymetric thrust (the more power in the good engine, the more critical) trys to roll the aircraft toward the bad engine (I think). The size of the rudder(s) and amount of air passing by (airspeed) resists that tendancy. In each certificated twin, there is a published airspeed called VMC, below which the rudders can no longer keep the plane upright, and your craft follows natures dictates. Much of multi training, and recurrent training (a must) is dealing with this phenomona.

Any piston twin, is marginal with one engine out.

Add to that taking off at gross weight, or over, a little bit of heat, or high altitude and you have a fuel burning rock. As you see your aircraft descending (even though you have cleaned up the plane's exterior, feathered the prop) with full power on the good engine, it is only natural to raise the nose a little, after all you have one perfectly good engine running, get below VMC and become aerobatic. This usually happens at low altitude. The results are predictable.

Twins are great for many things, such as over water flying, etc. If you loose an engine at cruise, you can generally get to a destination, but if you are heavy or hot, the good engine may just give you the ability to choose your emergency landing spot. the single engine service ceiling on a normally-aspirated twin is only in the range of 3-5Kfeet in best conditions.

My wife used to say, two engines, double trouble. There is twice the opportunity for an engine failure.

The most dangerous thing with a twin loosing an engine on takeoff is that the pilot must make several decisions, any one of which, if guessed wrong can be disasterous. If you loose an engine in a single, your decisions are limited.

Twin currency is vital

Rich ! Rich
__________________
CANARDLY CONTAIN MYSELF
Rich
Reply With Quote
  #12  
Old 12-20-2005, 10:49 PM
JonC's Avatar
JonC JonC is offline
LEz - N555LE Q - N555QA
 
Join Date: Jul 2004
Location: Mountain View, CA
Posts: 997
Default

Rich is very correct... the worst thing to ever do with a twin is to stall it on one engine. If you are lucky you will remain upright and all will be good. Most likely however, you are going to stall and do a very hard yaw/roll away from the good engine and end up upside down in a quasi-spin.... think bottle rocket tied to a pole, all thrust, no lift, therefore no directional control. You will loose quite a few thousand feet trying to correct that situation if you even can correct it.

Twins are dangerous planes if you don't fly them correctly.... at the same time they can be very safe planes if you practice and keep practicing.
__________________
~Nathan
Reply With Quote
  #13  
Old 12-21-2005, 10:12 AM
Spodman's Avatar
Spodman Spodman is offline
Wannabe - with plans
 
Join Date: May 2004
Location: Victoria, Australia
Posts: 486
Default

Quote:
Lets face it... with a well designed twin, and the knowledge and experience of how to use it you will make it to the next airport.
Sorry mate, I wasn't trying to bag you. I have a wistful dream that somebody would get an Anson Mk I flying one day, but with 2 engines and fixed pitch props it's single engine ceiling is ground level. With it and the mentioned Long having 2 engines does not make it safer.
__________________
Mark Spedding - the Spodman
Darraweit Guim, Australia
Theoretical Cozy IV 1331 - Celebrating 2 years of not building anything
Reply With Quote
  #14  
Old 12-21-2005, 11:24 AM
bferrell's Avatar
bferrell bferrell is offline
Member
 
Join Date: May 2005
Location: Cincinnati, OH
Posts: 174
Default

Quote:
Originally Posted by MarbleTurtle
Anyone have a picture of that twin-Velocity XL 5?
Unfortunately the twin is on the back-burner. I think I had a picture of the model around somewhere. One of the nice things about having a factory, though, is ongoing development. Right now they're testing the Hartzell pusher prop, an engine installation 'kit' for the turbo 550 conti, a UAV version for the military, a ballistic chute system, an air conditioning system, and the twin.

Apparently they've already got people lined up to buy the twin, but they don't have the resources to finish it right now. I think they said they were building 5 of the UAV's.

B
__________________
Brett Ferrell
Cincinnati, OH
www.velocityxl.com www.eaa974.com
Reply With Quote
  #15  
Old 12-22-2005, 11:11 AM
Dust's Avatar
Dust Dust is offline
Super Moderator
 
Join Date: Apr 2004
Location: Troy, Michigan
Posts: 7,963
Default

hey DarrellK - just send back the email that your email account probably put in the spam folder
__________________
Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 05:14 AM.


Powered by vBulletin® Version 3.6.7
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.