The most I would stuff into the nose of a Nobler would be a LA .46   -- The .51 Tigre would be to much power plus the additional weight would offset the benefits. If it flew great with the B.40, I'd stick with that. Just my 2 cents worth.

I've flow both Smoothies and Noblers with: OS-35S', Brodak .40, FP-40's and LA 46. The nice thing is that if you set up your plane for one, all of these will fit. Brodak 40 is perfect for either Smoothie or Nobler, LA-46 also, especially for the Nobler. ST-51...save it for a larger plane. And yes, either plane will do the pattern, quite well in fact.  

IMHO I'd put the B-40 in the Smoothie and the LA 46 in the Nobler. As far as one being better than the other, that is more airframe design than the engine in this case with the Nobler having the edge. 

I had a Fox 35 in my Nobler, in fact two different ones.  The first one came with it - out of the flea market shop - where I bought it.  It is very nicely built but recently I flew the outside wing tip into a light pole - ouch!   My brother is putting it back together - wing in two pieces and fuselage in two pieces.   The first Fox 35 - an old one - with one bolt hole broken off the case - it ran fairly well.  Then I got one of the newest editions - it ran well but I never felt comfortable stunting with it.  It came in on me.  Finally I figured that problem out but by then it had a B-40 on it - and then I wrecked it.  I accidently hooked it to 70 ft lines instead of 60.  Well!  However, I was just getting comfortable to do stunting when it collided with the light pole.

I may have a spare Fox 35 somewhere.

Also,  what is a good plane for the the ST 51 - a Pathfinder?  Cardinal?   Vector?   

Thanks again.

The most I would stuff into the nose of a Nobler would be a LA .46

I disagree..

The question of " Is the st .51 to much engine for a Nobler " I can answer.

As far as power I'd say no - Would I put one in ? the answer is also No. - For the reasons below.

SPECS:    Bore:   23mm (.905")
          Stroke: 20mm (.787")
          Weight w/o muffler:  313g (10.98oz)
          Weight with muffler: 459g  (16.2oz)

I regularly run ( and have won multiple National competitions in Classic Stunt ) with a 1951 Nobler powering it with a Stalker .61

yes STALKER .61 - So that is far more power than your St .51 - The problem I see for the ST 51 is weight.

You can see the specs show that the weight is 459 G with the muffler - and the muffler is side mount.

2 Main problems with the ST 51 is weight and weight balance.
The muffler weighs 146 Grams Engine 313 Grams Total : 459

Having THAT much weight makes balance for a little nobler extremely difficult - As I mentioned I run the Stalker .61 and more specifically the EX Lite edition. with rear exhaust light weight muffler.

Specs on that are : Muffler weights 45 grams and Engine 315. Total : 360 ( Thats 3.4 Oz LIGHTER )

The 2nd issue is the weight balance point. With a rear muffler the total weight is actually moved back further by at least 8 - 10 cm.
So not only with the rear exhaust is the muffler lighter but its moved further back.

This makes a huge difference to the balance point. Overall the weight is moved too far forward with the ST 51 - you have a huge amount of weight in a very concentrated forward balance point.

Even when running a Tuned pipe, you have the weight of the Pipe, but its so far back behind the CG that is doesnt matter to much - compared to having that all located within the front few inches.



So to much power ? God no.. Ive even run the Stalker .66 in the nobler. If your around at the US NATS - I will have a new classic model with stalker .61 with special Ultra light Custom muffler - flying in classic so you can make your own assessment of if its too powerful.

To give you an idea the Stalker .81 is still lighter than the St 51   - I dont have the specs infront of me but i suspect the PA .75 with tuned pipe would also be lighted than the ST .51 w/muffler.



I've had several noblers ( 10 + ) with everything from Veco .29 Upward..  im not advocating everyone putting an engine of my size inside. I do agree that there is alot of engines Like the Brodak .40 that will run it PERFECTLY. and the Aero .36 works exceptionally well.

Others have flown my nobler and EVERYONE has said - Its so easy to fly - Someone said " its like cruzing down the freeway in a Musclecar with modern engine and suspecsion. Just tickin along. With that much power - Ive flown it as slow as 6.5 second laps and make it REALLY slow but still drive slowly through the pattern.. Or you can dial in your speed as you see fit. Such a wide window of operation.
I personally have mine set up like other notable experts fliers have current CLPA models setup - Big bore engine, low down thumping power constant 4 stroke, constant speed. - Simply put results speak for themselves - Lots of torque with reliable power, reliable manouver speed over various conditions and various atmospherics.


Over kill ? Possible but as Randy smith says we now live in an age where we know how to set up engines for run characteristics that are favorable to Stunt. - Be it classic or CLPA.

Twice the size isnt the answer.. the engine is too heavy as it is..

Very interesting and informative discussion.  What are some other planes which would fly well with ST 51, beyond the SV 11 which was already mentioned?

What planes are being flown competitively with an ST 51?  This is the Chinese Version stock.  a bout 35 flights - runs great!

I ran the ST 51 on my Magnum and then for several years in my Shark 45 (at 66 ounces or so) and it flew very well.  Compared to other motors I don't think it's to heavy.  I toyed with the idea of putting it in a smaller airframe (say 630-650) but have never got around to it.

James

Compared to other motors I don't think it's to heavy.  I toyed with the idea of putting it in a smaller airframe (say 630-650) but have never got around to it.


True.. compared to a YS .120!!!!!!!!!!

Its just the weight - not the power

St51 :        459 Grams
Stalker .81  423 Grams

Im using the stalker as an example becasue ive got one here to weigh and I cannot find any weights on the PA engines - I suspect they are similar. - However if you must persist and build something an SV 11 would be ideal

I thought the G-51 was 313 grammes minus silencer ?

If you like the hair on the back of your neck bristle ,
and the rest to be on end ! Build a 52 in Span Martin Baker MB3
to Al Rabes aerodynamic Criteria . If it weighs 2 Kilo it will be
a very intresting exercise . In a 20 Knot wind the houglass
and cloverleaf are ' intresting ' .In a similar manner to being
stuffed in a drag race car , hands tied , with the throttle stuck
full on .
That said , it flew acurately and consistantly , couldve done
with the rudder connected as per his mightynesses manner .
Will do another LIGHTER one for an old Max 40 ( I hope ) .
            -----------------------------------

Italian Luchiano Compesstella did a 4 stroke thing in 1980 (enya)
I pirated the Airframe and did as a Spitfire . Similar weight (oh dear)
but very competant happy plane . Had a few obscure mods to controls
and was NOT scarey in any wind I flew it in ( 20 Kt. +).
Unfortunately the funny granching noise wasnt the Engine.
Twisting the elevators neutral once SPLIT the 2.7 wire pushrod to E. horn.
3rd flight with a Irvine 40 RE & 10x4 3blade prop, it disconected coming out
inverted from the wingover, dropped its nose from level.
The second correction the flaps acted as elevators as well .
The outer dihedraled wing was a bit second hand as was prop.
Nice trench in the field too . . .
Gotta do another 1 or 2 of them too . . . amongst other things .
Just one more !
If your useing a G-51 Id use adequate glue as you tend to get
some Forces at Work , at times. Great Fun if your not churlish.

I have plans for these monsters.

My G51 weighs 380 grams with its home made adaptor, Bolly CF Aftermuffler and silicon connector tubing. Using zero nitro fuel and a 12x5 Zinger prop it had more than enough grunt in a solid 4 stroke to haul around an 810 sq/inch 59 ounce model with ease (go on, work out the wing loading ). The engine itself is totally box stock (Italian) standard.

BTW:  Tom Dixon put one of his ST G.51 in his early orange and black T-Bird II.  He flew it really well.

Big Bear

Since it was brought it up, I remember that airplane as having a modified Royal 40 when Tom won an early VSC with it, not to say that he also didn't try it with a St-51. However, that version of the T-Bird had a 610 square inch wing, much larger than the 550 squares of the Nobler.
He did design a .51 sized T-Bird that looked identical to the 59 T-Bird but had a 630 square inch wing. It was never published but plans are available.  Built one, wing was warped, never flew right, cured me of my T-bird fixation.

Hi Pete,

Since Tom is a "local" so to speak, I have a lot of his older plans.  The .51 size T-Bird is one.  Dale Barry had a very nice flying one back in the pre fire days, and I almost built one when I saw his.  Of course, Dale's was white and PINK!  And, IIRC, he built it with an up right engine and turtle deck ala the first T-Bird, but other wise built form Tom's plans. 

Big Bear

"My G51 weighs 380 grams with its home made adaptor, Bolly CF Aftermuffler and silicon connector tubing."

Thats still heavier than a modern .61 - this was my only point.

I dont disagree with running a B 40 for that model either for a beginner.

Say Bill, I found the picture of my king size T-Bird. I ought to just cut off the tips and square off the wing...but then it wouldn't be a T-Bird.