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Building a J230


eckertwa
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Hello! My name is Wayne Eckertson and I live in Eugene Oregon, USA. I have 500 hours of flying time and a Sport Pilot license. I am a member and past president of my local EAA chapter.

 

I am in the early stages of building a Jabiru J230. I also have a HKS 700E powered Rans S-14 which I put together in 2007. I documented that build at http://s14build.blogspot.com.

 

To pay for my airplane addiction, I work as an Electrical Engineer.

 

I appreciate any advice and help I can get for my J230 build.

 

 

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Welcome to the forum Wayne. I recently finished a UL450 build and now have a real appreciation for paint prep and pin holes. You'll get to know what I mean. I used the Stewart Systems water borne paint system and ended up with a nice finish. I am not a painter but followed the instructions and it worked. Please pay great attention to your engine installation and cooling set up.

 

Regards, Laurie

 

 

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  • 3 weeks later...
Hello! My name is Wayne Eckertson and I live in Eugene Oregon, USA. I have 500 hours of flying time and a Sport Pilot license. I am a member and past president of my local EAA chapter.I am in the early stages of building a Jabiru J230. I also have a HKS 700E powered Rans S-14 which I put together in 2007. I documented that build at http://s14build.blogspot.com.

 

To pay for my airplane addiction, I work as an Electrical Engineer.

 

I appreciate any advice and help I can get for my J230 build.

Welcome Wayne,

I too work in the electrical game to pay for the fun times.

 

 

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IF you add a little bit here and there it will end up heavier than the factory built one by a bit more than you might think.. They fly OK . Just run out of trim effectiveness at both ends of the speed envelope. Nev

 

 

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Hello Keenaviator. I am a long way away from painting. Do you have a website with photos of your build?

 

I have spent the last several hours browsing Captain's J230 build posts, mainly the photos , and only gotten a through page 8 of 18!

 

There is lots of good info on there for me. Thanks Captain!

 

One of the mods I am planning for my J230 is to remove the mechanical trim and add electric trim. I plan to cut a section out of the trailing edge of my elevator and use a Ray Allen servo. Anyone have a suggestion for elevator trim tab size?

 

 

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Build it carefully. (the trim tab mechanism or it will flutter if it disconnects). Size Get the % area from a similar design. Some have the trimtab move as the elevator moves to Auto servo it. Be careful with all of that. At least it isn't a full flying tail. Nev

 

 

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rgmwa. Most airplane design engineers regard them as a critical part that MUST be very carefully designed , inspected and maintained. It's efficient but can have flutter consequences. I have owned a Twin Commanche which is a lovely plane in many ways . See the Vid on flutter with one on this forum. Nev

 

 

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Hello Planesmaker,

 

That would be great if you could send me some photos. Please provide the dimensions too. I would also like to know how much throw your trim tab is capable of and how much you actually use.

 

How effective is your trim tab? Would you recommend one of the same size or a larger?

 

My understanding (from what I have read) is that the J2/4 series planes are light in aileron athority but slightly twitchy in pitch. If this is true, I won't want to enlarge the elevator by adding an external trim tab. Building the trim tab into the elevator will also be more aesthetically pleasing. Comments?

 

I assume that a trim cut out of trailing edge of the elevator will have less chance of fluttering. (Does "assume" have the same, humorous, meaning for you guys in the Southern Hemisphere as it does up here?) A trim tab cut out of the trailing edge will be thicker and therefor more ridged than one made to extend from the trailing edge of the elevator.

 

I will also need to ensure a bullet proof connection to the Ray Allen Servo and mounting. I may consider mass balancing the trim tab or adding some friction to the hinge.

 

Thanks for the help.

 

 

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Hello Planesmaker,That would be great if you could send me some photos. Please provide the dimensions too. I would also like to know how much throw your trim tab is capable of and how much you actually use.

 

How effective is your trim tab? Would you recommend one of the same size or a larger?

 

My understanding (from what I have read) is that the J2/4 series planes are light in aileron athority but slightly twitchy in pitch. If this is true, I won't want to enlarge the elevator by adding an external trim tab. Building the trim tab into the elevator will also be more aesthetically pleasing. Comments?

 

I assume that a trim cut out of trailing edge of the elevator will have less chance of fluttering. (Does "assume" have the same, humorous, meaning for you guys in the Southern Hemisphere as it does up here?) A trim tab cut out of the trailing edge will be thicker and therefor more ridged than one made to extend from the trailing edge of the elevator.

 

I will also need to ensure a bullet proof connection to the Ray Allen Servo and mounting. I may consider mass balancing the trim tab or adding some friction to the hinge.

 

Thanks for the help.

I assume you have flown the standard trim set up in a J230, in which case disregard my comment.

 

I find the trim change is so small that I wouldn't worry about it. Rudder trim now that's a different story - I have spoken to a person (don't have his details unfortunately - from Victoria somewhere) who has done this and claims 4 hour flights with even fuel burn with no input from the pilot required.

 

PS he used a sprung centering arrangement on the top of the nose wheel leg with a vernier control on the dash. Sounded like the ducks guts.

 

 

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I have very little flying experience in a Jabiru. I have done a couple of intro flights but that is it. I have to admit my main reason for the interest in the electric elevator trim tab is due to my S-14 having a very sloppy mechanical trim. I bought the Ray Allen servo for my S-14 but found no easy way to attach the servo to the elevator due to the tube and fabric construction. Since I have the servo, I might as well use it on my Jab!

 

In-cockpit adjustable elevator trim is necessary due to speed changes and weight changes in almost every plane. Rudder trim is typically set and forget; it does not require an in-cockpit adjustment. Now my S-14 has quite a bit of p-factor being a high mounted pusher. I have adjusted my vertical stabilizer so that it flys straight in cruise. During climbs or decents (read: take offs and landings) I need to put in some rudder to keep the bubble happy. Since I have become used to this, it is not a big deal; in fact, the need for rudder adjustment in the pattern is just my plane's may of reminding me to stay on my toes (or rudder peddles ). In larger, faster, and higher flying planes, I could see the interest in adjusting the rudder trim in flight say for decents from altitude. I rarely have to come down from flight levels in my s-14!

 

What are the groups thoughts: Does the J230 or similar Jabirus need in cockpit adjustable rudder trim?

 

 

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Rudder trim is typically set and forget; it does not require an in-cockpit adjustment

It does not NEED a rudder trim. If you're happy with your statement fine, forget I even mentioned it. [i have mainly flow larger aircraft but have done over 700hrs in a J230]

 

 

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rgmwa. Most airplane design engineers regard them as a critical part that MUST be very carefully designed , inspected and maintained. It's efficient but can have flutter consequences. I have owned a Twin Commanche which is a lovely plane in many ways . See the Vid on flutter with one on this forum. Nev

Thanks Nev, I've seen that video a few times. Pretty scary. My aircraft has a stabilator too, so I hope Van's design proves to be a good one. The RV-12's stabilator is a simple rectangular shape with flat ends, so some builders have added some nice-looking aftermarket stabilator tips that add at least a couple of pounds of extra weight. There are about 350 RV-12's flying now and none have fallen out of the sky yet, but I decided against adding the tips and becoming a test pilot.

 

rgmwa

 

 

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Bill Whitney steers away from them and I regard him highly. With a large family of owners like you have with the RV's you can share info which is helpful. They also have a fair bit on Vne specifically as you might get involved with the TRUE which is limiting, rather than indicated airspeed at higher heights when descending

 

Having a separate pitch control. That you can fly with if the primary one fails is a good idea as you are dead without pitch control. A spring is not a separate mechanism but operates through the primary pitch control, so doesn't really count as a fail safe ( redundancy) arrangement.Nev

 

 

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Having a separate pitch control. That you can fly with if the primary one fails is a good idea as you are dead without pitch control. Nev

The stabilator is cable controlled and the anti-servo tab is electrically actuated with full-up to full-down in around 30 secs. Wouldn't like to have to rely on the electrics to respond fast enough if the cables failed, but it might be possible to get away with it if you were lucky/careful and the conditions were favourable. Hope I never have to find out. Apologies for the thread drift.

rgmwa

 

 

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  • 3 weeks later...
Hello Planesmaker,That would be great if you could send me some photos. Please provide the dimensions too. I would also like to know how much throw your trim tab is capable of and how much you actually use.

 

How effective is your trim tab? Would you recommend one of the same size or a larger?

 

My understanding (from what I have read) is that the J2/4 series planes are light in aileron athority but slightly twitchy in pitch. If this is true, I won't want to enlarge the elevator by adding an external trim tab. Building the trim tab into the elevator will also be more aesthetically pleasing. Comments?

 

I assume that a trim cut out of trailing edge of the elevator will have less chance of fluttering. (Does "assume" have the same, humorous, meaning for you guys in the Southern Hemisphere as it does up here?) A trim tab cut out of the trailing edge will be thicker and therefor more ridged than one made to extend from the trailing edge of the elevator.

 

I will also need to ensure a bullet proof connection to the Ray Allen Servo and mounting. I may consider mass balancing the trim tab or adding some friction to the hinge.

 

Thanks for the help.

Yeah Wayne, assume has the same meaning in the electrical industry at least. The first time I heard the full derivation of the word was when I did my first HV switching operator's ticket in the 80s. Tends to make you think.

I have a mate that lives not far from you around McMinville area, I visited him on the way to Oshkosh last year. He took me to Evergreen Aviation, Wow what a museum.

 

Regards,

 

Mike.

 

 

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Wow a Space Shuttle. I thought the Hughes Hercules was pretty damn good. The way it makes a centre piece of really effective. Do you know if there was a plan for a separate Shuttle hangar?

 

We spent several days with our friends there, Paul is a Mechanical Engineer. He also directed us to the Antique Power Museum at Salem. That was also great. You lads and lasses certainly know how to make Aussies feel welcome.

 

 

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I would follow the above trim system (added to trailing edge) instead of cutting it into the elevator.

 

A tab mounted to the trailing edge has a better leverage to work as a trim, which means it can be smaller.

 

Cutting into the elevator will mean adding a sub-spar for it to hinge on, adding weight aft of the elevator hinge, and the tab itself would then have thickness (to match the elevator) which will also add weight.

 

This will then require more counter balance weight to balance the elevator, adding more weight to the rear of the aircraft.

 

Although the Jab has a tail and elevator, it doesn't hurt to maybe incorporate a 'anti servo' system into the trim for feel and damping at speed.

 

 

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