RC-CAKES

My Feedback: (4)

Hello all. A buddy and I are assembling a Hobbico Avistar 40. I read about some of the mods to improve the aerobatics and better landing abilities. My question is what is a good engine to put in it? I want something with power - but not too big so that its extremely nose heavy. I was considering a 50 size or bigger.
ANy thoughts? I see some models claim the same size/weight as a 40 but with power of a 60 (or something).

The 40LA is weak... what is your experience?

Thanks!

AB Bob

My Feedback: (20)

A .46 would be plenty of power. If you do try a .60 engine, reinforce the wingjoint.....

SunShyne

My Feedback: (68)

a 46fx will haul the mail on that airplane. Anything heavier you are risking it imo. I dont think it is the end of the world if you went to a 60 but balance, flying weight, performance issues etc etc come up

My friend went from 40LA to 46fx and it was night and day

good luck

matt

AB Bob

My Feedback: (20)

Some pics from rcplanecrashes.com which might help change your mind. If I had a sixty sized plane, I'd use a sixty sized engine...FWIW. [sm=thumbup.gif]

http://www.rcplanecrashes.com/profil...239.php?page=3
http://www.rcplanecrashes.com/profil...186.php?page=7

ramboy

I don't see any epoxy in the second picture where the wings are joined together.

GaryHarris

Magnum .52 or Saito .56 four stroke. [sm=thumbup.gif]

RC-CAKES

My Feedback: (4)

thanks for the responses. I am considering keeping it a 2 stroke. Deciding between a TT or Magnum... perhaps the OS

ANy pros/cons between these? I want this to be a kickaround zippy aerobatic trainer... that i wont get bored with-> but I want to have a buddy fly it for training too. I plan to beef up the gear some to give it better clearance incase I want to throw on a bigger prop.

Suggestions?@! What would you do to have a zippy, fun trainer that zooms by! But is still fairly tame for a rookie with a buddybox.

Ernie P.

My Feedback: (3)

My grandson has two Avistar's; one trike and one taildragger. Beginners need a spare. (-: The taildragger has an OS .46AX; and the trike has a Magnum .46. Both haul the plane around with authority. I don't think any more power is needed with this plane; especially with a beginner. At full throttle, either engine will pull the plane faster than he needs to go; vertical performance is impressive with both. Any more power and it would be too easy to pull the wings off. He solo'ed yesterday; but the Avistar will still be a staple in his flying for a while yet.

Both the Magnum and the OS will do nicely; but you simply can't beat an OS 2 stroke. No trouble since the day it was installed new; never a deadstick; never a hiccough; just fuel and go. Beginners have enough to worry about, without adding in engine problems and adjustments.

An engine alone won't give you a "zippy aerobatic trainer". An OS .46 will certainly make it "zippy"; but anything beyond basic maneuvers will run the risk of leaving the wing behind. Some beefing up would be in order. Just my opinion from watching my grandson put hours on his planes. Thanks; Ernie P.

Texastbird

For my money I would use a Thunder Tiger .46.

Kostas1

Hello Sir!

My experience?

Ok,

the Avistar 40 ARF was my 1st and for sure most loved airplane i've ever had.
We all have sth to love most,right?

If i recall correctly,
i have bought it 5 years ago,
when i was a student by that time...

And immediately after my purchase ,
i started saving again,
for an OS engine.

I knew that it was going to be an OS LA series, cheap,trust worthy,easy to start/fly/maintain.

Eventually after 3~4 months i bought an OS 46LA.

Man,
that engine....never ever quit on me.

I don't even know what i did so good,
but that engine worked every time,during day,during night,hot wetaher,cold weather,0% nitro-15% nitro,full throttle until fuel tank empties.
Whatever you wish to,this engine was capable to do (ofcourse,LA's are not ringed...so not powerful to compete with ringed engines)

But for an Avistar the OS 46LA ,for me, worked excellent.

I believe though,
that because you mentioned the OS 40LA,well, that's going to be underpowered.

I also installed std size servos ,Futaba S3003 and S3004.Realtively cheap i guess.
Mmmm,
what else.
And for the engine i always worked it with APC 11x6.

If you want to ask sth more ,post it here!

Konstantinos
Athens/Greece

PS. I am so angry with myself for selling the Avistar after 3 years of continous flying...but you know...when you're a student you must sell sth,save some money and then buy sth more expensive (...and better flying/capable of course)

hugger-4641

My Feedback: (6)

I teach a lot of people to fly and currently have 3 Avistars that I use for this purpose. Two of them still have the Os .40 La and have plenty of power for basic flying if tuned properly with the right prop. But for aerobatics and performance, I put a Magnum .46 xls on one of my Avistars. It has all the speed and power this airframe needs and idles better than my Os .46 ax and fx engines on other planes. It has never deadsticked unless I wanted it to. I also took the dihedral out of the wings, made a larger rudder, and set my CG at the aft limits of the reccomended range.
Taking the dihedral out had a minimal benefit for inverted flight, but there is not much dihedral in the stock wing anyway, so you would be fine with a stock wing.
Enlarging the rudder made Knife edges easier to perform, but it still won't hold altitude forever in a knife edge, a .55 ax probably would help this, but would be harder to get the Cg aft.
Moving the Cg aft allowed a slower landing and more responsive control, but is still a very stable flyer. To get the Cg aft, I had to put the battery way back in the fuse and put the rx as far back as it would go. Hope this helps, and hope you enjoy the Avistar as much as I have!