Engine replacement

[Aztec Driver]

Since the STC's are no longer offered for the 200 hp Lycoming conversion for the Twin Comanche, I was wondering what the possibilities of obtaining the necessary hardware and having the installation field approved? Anyone have any experience in that realm?

Bryon

 

[Henning]

Since the STC's are no longer offered for the 200 hp Lycoming conversion for the Twin Comanche, I was wondering what the possibilities of obtaining the necessary hardware and having the installation field approved? Anyone have any experience in that realm?

Bryon

Are the design papers still available? It shouldn't be too hard, but why do you want to go to the IO 360s? Are you looking for speed down low or up high? Would turbos do what you want?

 

[bbchien]

Did Miller withdraw the STC? Or did he just stop supporting it?

 

[Dave2]

If the STC hasn't been withdrawn and you cannot contact the holder, the FAA has a method of obtaining such an STC.

 

[poadeleted20]

Expect to spend a minimum $30K and six months on testing to meet FAA certification requirements after you've spent the money to buy and install the engines. It might be cheaper to trade up to an airplane which already needs your needs/wants rather than modifying your TC.

 

[SCCutler]

Expect to spend a minimum $30K and six months on testing to meet FAA certification requirements after you've spent the money to buy and install the engines. It might be cheaper to trade up to an airplane which already needs your needs/wants rather than modifying your TC.

So, Ron: Let's say Bryon and some enterprising and talented soul (especially a mechanic/engineer type) do just that-

If they spend that $30G and take that six-plus months and demonstrate to the FAA the scope of their genius and skill, can they get an STC which they then can sell?

Assuming (without knowing) that it takes more, how much more?

Inquiring minds want to know. Mine, too.

 

[charlie]

If you want a Miller Twin Comanche buy one. If the mod were available today the cost would easily exceed $100,000 less the vaue of the old engines, props and other parts left over. Charlie Melot Zephyr Aircraft Engines and PA-30 owner

 

[flyingcheesehead]

If you want a Miller Twin Comanche buy one. If the mod were available today the cost would easily exceed $100,000 less the vaue of the old engines, props and other parts left over. Charlie Melot Zephyr Aircraft Engines and PA-30 owner

Charlie,

Is that just for the engines, or for the whole Miller package? (Engines, nose, nacelles, dorsal fin, etc.)

Wouldn't the old engines and props be worth a fairly significant sum too?

 

[charlie]

My guesstimate is just for the engine conversion. Runout IO-320-B1A's are hard to sell at all. Mid timers might go quicker but they only fit Twin Comanches so it's a limited market. Props are easier to sell because even though they only fit the TC the demand is there.

 

[poadeleted20]

If they spend that $30G and take that six-plus months and demonstrate to the FAA the scope of their genius and skill, can they get an STC which they then can sell?

Yes, but they'll need your legal expertise to help manage the liability they accrue with each copy of the STC they sell. The insurance to cover that ain't cheap.