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This covid-lockdown project has been going on for awhile; I hope to get the airplane flying again in the next couple months. 

The goals:

  • Better ground cowling by reducing the distance between the cowling trailing edge and the prop from 4" to <1".
  • Less airflow separation (drag) due to more gentle contours, especially at the lower trailing edge.
  • Increase groundspeed (how fast it looks like it's going while parked).

2020-11-15_16-53-12_743.heic 2020-11-28_17-15-55_839.heic 2020-12-05_16-26-13_975.heic 2020-12-05_18-29-25_959.heic 2021-01-10_17-20-00_996.heic

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Can anyone tell me how to make the attached photos display inline?

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See   https://fileinfo.com/extension/heic    Change your phone settings to save them as JPEGs.  I can open your .HEIC pics on my Mac. 

You had a pretty large gap before.  Looks more than 4", but I doubt you are going to gain much with this mod except  "groundspeed"    I am not sure a 1" gap won't make your cooling worse.  I don't think the prop pulls much air through the cowl on the ground and in flight, you might be blocking some of the cowl exit area with the closer prop.  Hard to say without before-and-after-tests so don't take that as gospel. 

If you have a ground-cooling problem, maybe you just need to shut down when there is a delay and restart just before takeoff.  There is no reason to keep the engine idling for  XX minutes when you can just shut it down.  A restart is EZ unless you are hand-proping.  🙂


-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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Amazon photos changed the file type. Will convert and repost. 

Thanks for the encouragement. I’m only a couple hundred hours in so what the heck 😕

Other canard drivers have reported improved ground cooling with a smaller gap. I’m hopeful.

An oil flow test showed significant airflow separation with the old cowling shape.  The new shape will definitely improve that; we’ll see if it leads to airspeed improvements.

And yes, I do hand prop like all self-respecting VariEze pilots. 

Edited by slk23

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4 minutes ago, slk23 said:

And yes, I do hand prop like all self-respecting VariEze pilots. 

Good for you.  I tried that for a while on my O-320 Cozy III but finally gave up and installed a starter.  But surely you don't idle long enough on the ground for it to be a problem?  Just make those Airbus A-320s wait while you get out and restart.  🙂


-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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Kent,

Yes, I do sometimes have to idle for quite awhile.  Why you are so skeptical?

This VariEze has a Lycoming O-235.  Weight and balance would not be pretty with a starter, as much as I'd like one.  But I've come to appreciate hand-propping because I am immediately made aware of leaking valves, etc.  It's also satisfying to develop the skills involved. 

More pix to follow.

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2 hours ago, slk23 said:

Can anyone tell me how to make the attached photos display inline?

 

1 hour ago, Kent Ashton said:

See   https://fileinfo.com/extension/heic    Change your phone settings to save them as JPEGs.  I can open your .HEIC pics on my Mac. 

The HEIC file format is relatively new and is catching on, but not fast enough for the forum hosting service to keep up with it. It will happen eventually, but until then JPEGs work. 🙂


Jon Matcho :busy:
Builder/Administrator
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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