Welcome to the Timber Tiger ST-L Subforum - Introductions

[Dfegley]

Empty weight: 800-830 lbs
Gross weight and limit loads: 1,420 lbs @ 3.8G+/2.0- G
1,350 lbs @ 4G, 1230 lbs@ 4.4+/2- G
Clipped wing option: 1,200 lbs @ 6 G limit, 1,420 lbs @ 4+/2-G

Engine options from 100-140 hp.

The original Ryan ST series had an inverted inline Menasco pirate engine ranging from 100-150 hp. The Rotax 912, it is a very light engine by comparison, and for the Timber Tiger ST-L design to faithfully follow the lines of the Ryan ST, a bit of nose ballast is necessary to bring the CG to where it needs to be. That said, a higher firewall forward weight isn't likely to be a problem giving you more engine options. Figure the max engine weight is around 230 lbs. The caveat is selecting an engine that fits the narrow confines of the inline appearing cowling.

We have a builder using a Verner 7 cylinder radial, and another using the UL Power. We also show options to use a small Continental with the cylinders poking out the sides kinda like a cub.

Hey Glenn,

I’m a new ST builder, and loving all your posts and photos! We met at Oshkosh ‘24. Q: What is the internal width of the cowling, i.e., I’m thinking of what engines can fit that width? The ULPower option would have the great sound of direct drive, but it’s wider. I have more questions later on your landing light installation, etc. Thanks!

 

[32fordboy]

Hey, Dwight! Glenn must be busy getting his hangar filled back up after painting his floors. Your timing is uncanny, though. A builder who is currently installing a UL Power engine needed some additional cowl drawings, so I whipped some up today. I'll send them to you.

The UL Power engine will fit from a power and weight perspective, but the cowl will need either cheeks to clear the cylinders (think Vans RV-4), or will need cooling eyebrows of some sort, similar to a Cub. One of our other builders is using a LyCon O-235 with 140 hp and is opting for the hot rod look of the cooling eyebrows.

 

[SierraWhiskey]

Hey, Dwight! Glenn must be busy getting his hangar filled back up after painting his floors. Your timing is uncanny, though. A builder who is currently installing a UL Power engine needed some additional cowl drawings, so I whipped some up today. I'll send them to you.

The UL Power engine will fit from a power and weight perspective, but the cowl will need either cheeks to clear the cylinders (think Vans RV-4), or will need cooling eyebrows of some sort, similar to a Cub. One of our other builders is using a LyCon O-235 with 140 hp and is opting for the hot rod look of the cooling eyebrows.

Nick,
Has anyone asked about the higher horsepower Vikings and/or Aeromomentum engines? (People have feelings about the suitability of these engines, so you might not want to go there ...)

 

[32fordboy]

That has been a common question. I don't know much about either brand, but we did obtain a CAD model to verify that the Aeromomentum AM15 will fit. It will if it has the higher thrust line gearbox. That's about all I know at this time. As with any engine, it really boils down to the honesty, knowledge, and support of the manufacturing company along with proper planning of the installation on the part of the builder. From what I've seen of poor engine installations, people usually deviate from accepted aviation practices or start plumbing the fuel, oil, or coolant with zero clue what they're doing and no desire to research/learn. I call that "blind confidence".

 

[SierraWhiskey]

Thanks, Nick. Both companies appear to be building credible hours, especially Viking with the Zenith 'bread box' crowd.
Time will tell ...