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What did you do on your airplane project today?

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Toobuilder

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...also not sure if the picture is making that chin scoop look like its just a flat plate with a hole in it?

If its like that in real life, I'm betting a few hours and some foam/fiberglass would make a streamlined add on pitot inlet that would add 5 knots in drag reduction and add half an inch of MP.
 

cblink.007

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Jul 7, 2014
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Texas, USA
I have not done so much building and such as I have been getting all my workshop stuff ready for the move up north to Maryland. I have the test model wrapped in enough seat cushion foam that you can throw the wings and centerbody off a roof, and not worry about it breaking! Once unpacked and set up, we will finish prepping the thing for initial flight trials!
 

Victor Bravo

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A note to others is to check the spinner flange on occasion for signs of fatigue. I lost a spinner during a high speed taxi test on a different airplane some years ago. The momentary vibration untill it departed the aircraft in a beautiful arc was astounding. Had the separation taken place in flight, it wouldn't have been so beautiful.
I probably shared this story before, so please forgive any repetitive preaching, but I lost a spinner in flight once. Lucky for me it was a fiberglass spinner on the front of an RV-3, and it was a wood propeller with less rotating mass than a metal prop. But it still shook the holy s**t out of the airplane and rather rudely stained a good pair of nice white underwear. The root cause of this was owner/operator stupidity and impatience, but (of greater relevance here) the immediate cause was not paying enough attention to a problem with one of the nut plates around the backplate flange.

In my case, the airplane was not damaged, and the pilot's ego required a major overhaul... but the underwear was unfortunately not repairable.
 

Victor Bravo

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...also not sure if the picture is making that chin scoop look like its just a flat plate with a hole in it?

If its like that in real life, I'm betting a few hours and some foam/fiberglass would make a streamlined add on pitot inlet that would add 5 knots in drag reduction and add half an inch of MP.
1000% agreed, that sheet metal intake scoop is pretty draggy looking. The exhaust pipe coming out at 80 degrees to the local airflow is not helping either. A couple of small aluminum fairings at the front/rear of the exhaust pipe would help, but shortening it and changing the angle would help more IMHO.

I would also like to suggest a baffle or some kind of seal behind the spinner (unless you have individual sealed plenum boxes above the cylinders).
 

malte

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Feb 5, 2011
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81
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Flensburg / Germany
Today was good. We managed to hang the engine with the help of the forklift of our racetrack-friends. It helped a lot that the fuselage is stored on wheels and can be moved in any direction. Hopefully we're seeing flight this year!
 

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gtae07

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Dec 13, 2012
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Savannah, Georgia
In the last week or two:
  • Locaed the last firewall equipment other than wiring/control penetrations
  • Drilled tailwheel strut to the airframe
  • Ran smoke oil line
  • Bored out my alternator pulley to fit
  • Ordered exhaust system, smoke system components minus pump and tank, misc other supplies, landing gear upgades,
  • Updated my to-do list (a huge help at this stage!)
  • Added wire penetrations for tail nav/strobe including turning a small delrin bushing
  • Bought a tool chest to try and stay more organized
  • Prepped firewall penetration fittings for install
And in between all that I got a little formation practice too. Still trying to nail down panel layout--in few months I'm going to be ready to start installing switches and such, at least, and I need a layout fixed before I can do that. Planning on getting it waterjet cut or something.
 

Doran Jaffas

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Jun 25, 2019
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It looks like you have several degrees downwards tilt in the engine. Is that true with the Tailwind or an illusion of the picture?
Sorry for the late reply.
It must be an illusion of the picture. The cowling slopes a bit but not the engine.
On the " What did you do on your airplane today " topic,, I and a friend of mine worked on fitting the new spinner and propeller today. Backing plate, bulkhead, cuts for the prop etc.. Unless longer prop bolts are needed the whole business should be ready for primer and paint tomorrow... hopefully. If I do need longer bolts, a call to Aircraft Spruce with excessive payment for next day shipping will be done Monday. ( Today is Saturday ).
 

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Mcmark

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Sep 24, 2013
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Owings, MD
So over the weekend I built a new suction hose from the 3 way to the pump. Finished the tidy up of hoses and cabling. Put the big battery back in the tray and gave it a whirl. Turned nicely and fired up on the 4-5 blade. Only running on 2 plugs on left mag. Pulled the mag back off and checked it. Sparking on all 4. Had trouble getting harness off, thinking I had the harness fouled in the cap. Will take another over and reinstall. The only items left are the rubber seal at the baffling, the spinner, final tune of the TBI, it’s FAT at idle. Hang wings and rig. Closer!
Ignore the bald pate and the phone kept falling over so it’s caddywompus.
 

gtae07

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Drilled the (hopefully?) last firewall penetrations for wiring and control cables. Made a new fuel return line because the previous one ran right through where my throttle and alt air cables need to go.
Riveted and sealed the firewall recess.

Next:
Brake pedal fab & assy, and rudder/brake assy installation
Firewall insulation fitting and trimming

To decide soon: hang engine first and start on cowling, or start initial fitting of canopy (minus the skirts/fairings/finish work).
 

gtae07

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Past week or two:
Installed and sealed most of the firewall penetrations. Brake and smoke oil fitings left to do.
Cut and trimmed the covering that goes over the firewall insulation.
Fabbed brake pedals, assembled them on the rudder bars, and installed them.
Ordered interior, worked on panel and electrical layout.
Drilled the rest of the tailwheel assembly to the strut.

Next:
Finish firewall, do brake system firewall aft, install some wiring conduit, and start on canopy rough-in.
 

pwood66889

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Feb 10, 2007
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Sopchoppy, Florida, USA
Worked voltage regulator and wiring; nose strut to engine mount fitting revealed a part 90 degrees ill-installed! Flinking manuals anyway...
Also a thrust washer problem in the engine - with help from this forum!
 

Toobuilder

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Did some tuft testing to see if my gear leg fairings are zero AoA in cruise. Spoiler alert - they weren't.

Did a change and while my yaw trim got better, my speed didn't improve much. New plan is to build a "section" of fairing that's free to rotate about the gear leg. Theory is to fly, let it streamline, then capture the angle/position on film.
IMG_20201127_132726915_HDR.jpg
 

mcrae0104

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Oct 27, 2009
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Did some tuft testing to see if my gear leg fairings are zero AoA in cruise. Spoiler alert - they weren't.
Which way is the local flow going? Somewhat inboard as it flows aft (due to the influence of the constricting propeller outflow)? I'm also wondering if the fairing might need to be twisted to achieve zero AoA, and how much drag you will save. Looking forward to your results.
 
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