Parts Interchangeability

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Includes: Highlander, Escapade, Summit and SuperSTOL.
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tlbrush
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Parts Interchangeability

Post by tlbrush »

Hello everyone. I am new to the forum and have read many of the posts. I have not purchased a kit yet but have some questions for some of you with some building and flying experience under your belt.

1. How hard would it be to swap wings after construction is complete? Say moving from the standard Highlander wing to a SS wing? Would that even be a good idea?

2. Could I mount Highlander wings on a SS XL fuselage? Would that be a good idea?

3. Would any of the other Avid derived aircraft (ie Kitfox) wings fit on a Highlander?

Thanks in advance,

Tony
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danerazz
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Re: Parts Interchangeability

Post by danerazz »

I have wondered this, as I would like a XL with standard wings. I believe they would mount fine, and I am pretty sure some of the early SSs were standard highlanders with gear mods and the new wing. Should be able to do the reverse.

I would actually prefer a standard highlander XL, with the regular gear setup, but so I could put a slightly heavier engine on it. Might want to add a foot or so to each wing.

To answer your questions (and somebody may correct me)

1. I believe they physically will mount right up, may need fairing changes at the root and new control cables, plus the “fuselage rib” will change

2. I think it would work that way too, just not sure about wing loading between the wings (see note about extra couple feet added to span). I think it is a good idea, but what do I know?

3. I can’t address this as I have no knowledge, I would be surprised. There are significant control differences just for starters. Also, neither company will likely want to support such a venture.
Dane

Paralysis by analysis
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tlbrush
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Re: Parts Interchangeability

Post by tlbrush »

Thanks Dane. I don't know what the extra length of the XL would do to CG if much at all. I agree that a lengthened wing would be a good addition as well. Not sure how much additional weight this would add.

It seems to me that the added fuselage length may decrease prop clearance a bit but that may not be much of an issue with bush tires on it and may make view over the cowl a bit better.

As far as swapping out the wings, I was just wondering if I might be able to come up with a faster wing for cross country flights and put on the original Highlander wings for back country operations. I wasn't sure how much work would be involved and if I would run into any issues with and experimental with the FAA when swapping major parts like that.

I know these questions might be very naive but I need to start my understanding somewhere.

Tony
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danerazz
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Re: Parts Interchangeability

Post by danerazz »

The longer fuse is meant specifically for larger engines (lycoming O-320/O-360 and such). It is longer both at the nose and tail, but balances better with more weight on the firewall.

Swapping the wings would be a major change and require a Phase 1 testing period again, but probably only a 5-10 hour one. That probably would only be for the first swap, as the handling would then be known after that.

The hassle of actually removing and reinstalling wings would probably not be worth it, unless you were doing A LOT of x-c flying then maximum performance STOL competition. You run the risk of damaging the wings, have to deal with draining fuel tanks, potentially having to replace fuselage control cables, possible fuselage fairing changes, etc. The performance increases either way would likely not be worth the efforts.

But, some things are worth it to an individual, like putting a radial engine on :wink:
Dane

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tlbrush
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Re: Parts Interchangeability

Post by tlbrush »

Dane when you say bigger engine, you specifically mean longer and heavier (which normally means more powerful) which would reduce useful load on an 1320 max aircraft correct? A higher horsepower engine like an Apex that is not significantly heavier would not be considered a "bigger engine" in this case as it would not move the CG significantly?

Moving back to the tail feathers....any benefit from swapping those with other planes in the family?

Tony
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BucF16
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Re: Parts Interchangeability

Post by BucF16 »

Hi Tony, Highlanders and then SuperStols were sized to accommodate the Rotax 912 ULS 100 hp engine. It weighs just over 150 Lbs. The SS XL is sized for the Titan engine 274 hp that weighs 260 -290 Lbs. Therefore the XL length.

Cheers,
Bruce
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
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SheepdogRD
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Re: Parts Interchangeability

Post by SheepdogRD »

tlbrush wrote:... when you say bigger engine, you specifically mean longer and heavier (which normally means more powerful) which would reduce useful load on an 1320 max aircraft correct? A higher horsepower engine like an Apex that is not significantly heavier would not be considered a "bigger engine" in this case as it would not move the CG significantly?
Not necessarily longer and heavier. It's a matter of maintaining the CG. If you've ever seen a turbine Otter, the radial is replaced by a turbine --- which is much lighter -- way out on an extended nose.

The Apex is heavier than the Rotax, especially with turbocharger and intercooler, so it should sit further back, but the firewall is in the way. An Apex installation might benefit somewhat from the longer airframe, but it's not as heavy as a Titan, so it might require a longer nose to maintain the proper CG.

You don't have to lose useful load, because you can increase the gross weight... as high as 1550, I believe.
tlbrush wrote:Moving back to the tail feathers....any benefit from swapping those with other planes in the family?
If you're going to modify the tail, you might be better off changing what you have, instead of trying to make someone else's stuff fit. Jim Pekola put a full flying tail on his "Highlander Extreme", so significant changes are possible.

The "family" of airplanes has some of the same DNA, but parts interchangeability is severely limited. The Avid is a static design, but the Just and Kitfox lines continue to evolve well apart from the Avid and from each other.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
tlbrush
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Re: Parts Interchangeability

Post by tlbrush »

Thanks for all your insight. Sounds like my first build should be pretty standard and then see if there is anything that really stands out as needing improvement.
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SheepdogRD
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Re: Parts Interchangeability

Post by SheepdogRD »

tlbrush wrote:Sounds like my first build should be pretty standard and then see if there is anything that really stands out as needing improvement.
Yep, that's what Troy told me when I first started my Highlander: decide on the options you want, and build it stone stock. Don't make changes, because they take way longer than you think they will. After you get the first one done and flying, decide what changes you want. You can build them into your second one, which will go a lot faster because you have experience.

If I'd followed that sage advice, I'd have been flying her years ago, and be well into the second or third one.

It's a lot like cooking: the first time you make something, just follow the recipe.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
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BucF16
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Re: Parts Interchangeability

Post by BucF16 »

Good Morning Tony, I completely agree with Richard. There are however a few mods that take little effort that will enhance the capability of your NEW Highlander/Superstol. I purchased a Highlander with extreme gear. In my case I went straight stock, except ......
Billy Payne's Chrome molly doors.
Molded windshield (I don't know who is manufacturing these today).

From Steve Henry:
TK Racing"s tailwheel assembly (It's uses a nitrogen shock) In hind sight, I would just order the SuperStol tailwheel assembly for my Highlander.
Leading edge cuff.
Firewall forward with apex engine.

Oratex covering.

MGL avionics

All of the above is to get this aircraft in the air sooner.

When I finish Phase one testing I will, Through Steve, purchase TK Racing's new new Highlander Extreme Gear and shocks.

We shall see how this all turns out. After all this is "Experimental Aviation". :D
Bruce
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
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BucF16
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Re: Parts Interchangeability

Post by BucF16 »

Crap, I forgot to mention Chris Wallen’s Flying tail Mod of the original stock tail feathers, and aerodynamic jury struts.
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
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