droland

I have one of thes Yak 54 50 just arrived and read about the stablilizer failures.
All of the posts I found were dated 2007 or earlier.
So I'm wondering if they got that issue fixed now that it is 2 years later?

And I mean on the original model.
[link]http://www.nitroplanes.com/yak543d5056n.html[/link]

I know they have a Version 2 that states it has beefed up stab and fuse, but I apparently don't have Verson 2.

Anybody built one in the last year or so?

nitrostaff1

Yes that issue was solved quite a while ago. The new stabalizer it reinforced.

John
Nitro Planes

droland

Thanks for the reply John.
I was hoping some bulders/pilots would have given their latest experience though.

SkaBob

Just about finished building mine, and the wood in the stab is pretty hard. Mine was ordered in April, so I'm not sure if mine has the updated tail or not (John? How long has the new tail been in production?), but it's definitely a harder wood than in myOMPProYak's stab. Just got to give it the finishing touches, then I'll be maidening it this weekend, so it'd be awesome to know if I need to re-enforce it before Ihead to the field!

droland

Thanks Bob. I'm actually helping a bud with this one.
Although the stab seems OK, I thought the Joiner Wire looked a little weak and told him he may want to make a stiffer one.
He went ahead and put it in the stock one and sure enough.... it is so weak it will not work for sure.

It looks like our best option at this point is to go with 2 elevator servos and move the rudder servo to the pull-pull location.

What engine did you go with?

We have an Evolution 61 we are trying to use.
It's a little large for the cowl though.

SkaBob

Oh..yeah... Now that you mention it, I didn't use that joiner wire. Went heavy duty on that!

I've got a YS63 in mine. Ihear it should have it overpowered just about right

SkaBob

Well, Ihadn't heard from John in this thread about whether or not mine would've been one of the new models, so just to be safe Iput the re-enforcement bits from an old Vectorflight Edge on the tail. Should make it a non-issue Just gotta put the switch in, add some weight to the nose and take it out to maiden it this weekend!

I was surprised at how tail heavy it is, though... With the battery all the way up against the firewall, it still needed 4.5oz or so of weight added to those nose to balance at the spot listed in the manual (120mm from leading edge). Iknow the YS63 is light, but that was really surprising!

opjose

That is part of the YAK 54 design... needing to move weight forward.

I have Yak 54's from various manufacturers and ALL are quite consistent in this.

Don't add the weight as you've done though.

Instead affix the battery to the engine mount with wire ties and on foam servo tape.

This moves if further forward than the firewall, which gives it more leverage, and in turn resulting in less or now additional weight required.

I've done the same thing with my big Gasser Yaks.

droland

Well SkaBob
I was worried about my Evolution 61 being too heavy since its probably 5 ounces more than yours.

Seems that may not be a bad thing this time.

It may balance out pretty close then based on your experience.

====
And opjose, I have a 50CC YAK that is the same way, real tail heavy to start with.

Everything has to go in the cowl to get it to balance.

SkaBob

Yeah, if it's 5oz heavier than the YS, you'll be pretty close to perfect balance right out of the box!

I'll see about getting the battery into the cowl. I'm not sure there's much room in there, but that would definitely get more leverage into it...

SkaBob

Well, the stab survived the maiden, but I'd recommend you double, triple and quadruple check (and double, triple and quadruple re-enforce) the glue for the landing gear mount!

We filled the joints around it with thin CA and the parts we could reach with 5min epoxy, and figured it'd be OK. First landing, the cheap-o wood glue the factory used came apart and the whole landing gear mount snapped free, along with the triangular re-enforcement blocks that came attached to it!

Glue failure, probably not a design failure...though personally I'd have used a thicker piece of ply for that mounting plate.

Should be fixable, soIshould have it up flying in a few weeks (Katana MDon the way from PA...I'll probably get that flying before Iget the Yak back in the air).

I was surprised at how maneuverable it was for how small the throws are compared to my OMPPro-Yak! This thing really maneuvers! Really stable when we tested out it's stall behaviour, too!

It's also a lot faster flying than Ithought. With the YS63 and an APC14x4W on it, it was flying almost as fast as my Venus 40 pattern ship! Compared to a comparably sized Extreme Flight Extra, I was really surprised at how much air speed it carries... Bear that in mind when landing, if you're the type who tries to float in for landing!

droland

Thanks for the tips.

I had been looking, looking and looking again at that landing gear mount.
I just knew we should try to get some tri-stock epoxied in there somehow.
It's not going to be easy to reach.

Sorry to hear your gear got broken. You'll get it fixed up though.

We have been slow on getting this Yak in the air.

I have been spending more time on the 88 inch 50cc Edge.

Too many projects at once I guess.

Happy flying.