Stufing 51 in Skylark

[Bob Reeves]

The stuffing operation has began. Replacing the ST 46 with a ST 51 in my skylark has presented a few surprises, some OK and some not so OK.

My eyeball measurement of the front mounting holes to the drive washer was off but the combination of a narrower drive washer from a ST S 40 and a recessed Dubro plastic spinner will make the spinner fit acceptable. The Brodak spinner really looked good but it would require adding length and refinishing the nose..

The exhaust stack is higher and farther back so will have to rework the exhaust cutout in the cowl. With a sprinkler venturi the needle is going to end up the same height but is 1/8 inch farther back.

The 51 is two ounces heaver but can save 1 1/4 ounces by switching from the Big Art muffler to a Scott Dinger muffler and .2 ounces between the Brodak Spinner and plastic. Net weight gain is only going to be a little over 1/2 ounce.

[proparc]

Bob, I plan to purchase a PA 61 side exhaust from Randy for applications just like this.

[Bill Little]

Bob, I plan to purchase a PA 61 side exhaust from Randy for applications just like this.

Hi Milton,

I'm putting a RE PA 51 in my new USA-1.  Got a header muffler from Randy for it, and it's a go, Houston!

Bill <><

[Ron Merrill]

Bill, what is the reason behind a header muffler on your PA .51, instead of a pipe? is it less hazzle or is there another reason? THe reason i ask, an RC guy traded me a GMA/JETT .51/header muffler for a RC kit i was given. Info please. Ron.

[Bill Little]

Hi Ron,

I just don't want to pipe the USA-1 that I will be using for Classic.  The PA runs great on a muffler as well as the pipe, so I won't be hurting there.  Just preference for Classic.

There will be a USA-1 for a .61-.65 pipe.

Bill <><

[Ron Merrill]

Bill, i see. I am going to use the muffler also. Ron.

[Ralph Wenzel (d)]

A G.51 in a Falcon? Holy Rocketship, Batman!

[Bob Reeves]

Flew the Skylark for the first time today with the .51... Best I can say is it exceded all my expectations. I missed the ST 60 era but if this is what it was all about I really regret missing that era in this hobby. I love ST 46's because that was my classic era, I now understand why everyone went to the 60.

Just for the record the airplane weighs 55 ounces, around 12.8 ounces per foot wing loading. Still have a few small (I hope) trim issues with the airplane but that engine is great.

[Bill Little]

Hi Bob,

I'm freal glad to hear that you like the ST 51.  I've always said that it is probably the most overlooked "bigger" really good stunt engine out there.  Especially for less than $100!

I have a Skylark on the build list, and I have planned from the start to use the ST 51 in it.  I have had great luck with those engines. Just flip and fly! 

Bill <><

[Joe Gilbert]

Bob let me fly The plane today it will be very good. Engine is still  new but is running very good ,these may be a truly good engine. Oh the plane is very smooth. thanks Bob for the flight.