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Io-390 stc

jrichards

Sponsor
Supporting Member
Sponsor
South Burlington, VT
Aircraft Year
1978 580
Aircraft Type
Super Commander
Reg Number
N555LP
Serial Number
14405
Hi All,

How many interested in an IO-390 STC for 112 and 112B?

Negligible weight change.
Estimated installed horsepower increase of 30HP (18%).
Brand spanking new engines... $33K + $17K STC = $50K turn key.
Compare to current estimated $35K for installed reman IO-360.

This is a project introductory proposal. Jay Borden is on board for his 112 and would be first to fly, aiming for Dec this year with a brief hiatus in Experimental while we do the vibe survey, exhaust approval and STC test flights. Other installations would proceed starting in 2Q 2009 and would be fully certified for Standard Category.

The deal is thus:

To participate in this introductory offer, you put up a $25K project investment now which is reimbursed back to you at the rate of $500 per IO-390 STC sold by Aerodyme. If we eventually sell 50 packages, you have recouped all. If we sell eventually sell more, you recoup more up to a cap of +$25K return on the $25K invested.

When you are ready for your engine package, you pay $50K for the brand new engine and STC package, installed turn key. For installations not completed by Dec 2009, we would need to add any cumulative price increases by Lycoming with the baseline being the 2008 OEM price of $33K for the new certified IO-390's. The introductory pricing would expire at the end of 2010 but the return on your project investment would continue.

The IO-390 is a forward inlet engine and will change performance more than the rated step up of 200HP to 210HP. This is similar to how our IO-580 STC steps up 114 performance by an effective 90HP even tho the book says it should be just 60. We intend to perform this same magic for the IO-390 112's.

Many of your Commander airframes are in great shape and well set to fly ANOTHER 35 years but those 70's engine cases, cranks and cams are NOT, and most of you could well use a bit more climb and zip while hanging onto the economy of a four-cylinder engine.

This offer is limited to five participants, including Jay, thus leaving four slots of which I need three commited to start the project.

Rob H. from down under, hope all is well and might you still be interested?

Questions welcome and responses encouraged.

Jim
 

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Re: Io-390 Stc

Re: Io-390 Stc

Hi Jim; sounds like a great option for the 112s; but what could be done for the meager wing life limits? I know for most, 6945 hrs. 112s/112As and 8878 hr. 112Bs are quite a ways off for most, but would seem to make inve$tment sense w/the IO390 STC.

Judi
 
Re: Io-390 Stc

Re: Io-390 Stc

Jim

Which option are you recommending for 112TC drivers (390/540/580?)

Matt
112TC
99w
 
Re: Io-390 Stc

Re: Io-390 Stc

Any hope of an all up weight increase also

Matt
112tc
99w
 
Re: Io-390 Stc

Re: Io-390 Stc

Hi Judi,

Do you have any info on the average TIS of our fleet, particularly the 112's? If the average is around 2,500 hrs TIS then another 35 yrs would only put a few airplanes
within sight of their wing limits.

See you at the fly-in?

Jim
 
Re: Io-390 Stc

Re: Io-390 Stc

Jim; fm the ones I hv info. on, I'd say avg. still 3000-3200 hrs. or so. and yes, quite a long ways away fm 6945 hrs., but can the wing life limit get lifted?? .getting rid of that issue could really open the door for an IO390 expenditure. remember there are only 279 112s on US Registry. 112Bs? I think just 20.

hope to see ya'll next mo.
Judi
 
Re: Io-390 Stc

Re: Io-390 Stc

Hi Matt,

Anecdotally, I'd like to get one of these 390's flying and characterized because we might come very close in performance to the six-banger 114. We know from reverse proof that the IO-540 is only developing 210HP or so installed in the 114, and I think I have a good shot at achieving 190 HP with a well-engineered installation of the 390. Then, considering the 390 is a lighter engine and the 112's are lighter planes, you can see the basis for my optimism.

With that said, anyone who can afford a 580 and holding out for a rocketship should wait and go 580 once I get eligibility and approval of a weight increase for the late models. We are working now the airframe mods that will be necessary on these planes to get the six-cylinder on board and get at least the 114 certified weight. In any case, I would expect that whole package to run $125K versus less than half that for the 390.

Jim
 
Re: Io-390 Stc

Re: Io-390 Stc

Jim,

Although my '76 112A is certainly not a beater (IMHO), TIS is running around 4100. Coming up on another engine in the next year or two, so the interest is there, but difficult to justify 50K engine for an aircraft w/ a life expectancy of 10 years or so (w/o wing life extension).

Some one was working on and off on a mod that would extend the life limit. That would be very valuable for all of the 112's and 112A's and the discussion was that it wouldn't be overly complcated to accomplish the task based upon similar extensions granted to other aircraft. Has your operation looked at all into that effort?
 
Re: Io-390 Stc

Re: Io-390 Stc

Judy,

My 112A has only 1700hrs. Maybe we should take a poll of all the 112 drivers here on the site to see what the average airframe time actually is.
 
Re: Io-390 Stc

Re: Io-390 Stc

do it Thomas. most aren't as low as yours.. but also not that many over 4000 hrs., either. I'm only going by the 100 or so + I hv info. on.

Judi
 
Re: Io-390 Stc

Re: Io-390 Stc

quote: [We intend to perform this same magic for the IO-390 112's.]
if IO390 is only rated @ 210 HP.. and for an already 200HP IO360.. explain more how the cost makes cents.

Judi
 
Re: Io-390 Stc

Re: Io-390 Stc

Curious ... would the STC be good for hot shot flyers as well?
 
Re: Io-390 Stc

Re: Io-390 Stc

Jim quick question.
From your statement: " We know from reverse proof that the IO-540 is only developing 210HP or so installed in the 114".
How much HP is the 580 generating on the straight 114s you have done so far?

Also you mentioned: "
This is similar to how our IO-580 STC steps up 114 performance by an effective 90HP even tho the book says it should be just 60 ".

Let me see this math. If we assume that both engins, 540 and 580, develops all their HP then the difference is 45 HP. The 580 is rated at 315HP by Lycoming while the 540 is rated 270HP. So if you say that the 540 develops only 210HP then according to you the 580 develops 90HP more than the 540 which comes out to be 300HP. a loss of only 15HP. So are you saying the 540 looses 60HP on installation and the 580 looses only 15HP?

WOW!
 
Re: Io-390 Stc

Re: Io-390 Stc

A couple of points. I was the guy who initiated the Wing Life Extension. I contacted Paul Sterling (who has the Tomahawk STC) and he has done a bunch of research and has a 112 wing in his testing device. I have not had contact with him in quite some time and do not know if he has any concrete solutions but Jim, a follow up with you on this may lead to some results.
I am due for an engine anytime now and would be interested in the IO-390 if I could retain the HS. I would think that it would require a completely new STC for use with the 390 though.
 
Re: Io-390 Stc

Re: Io-390 Stc

Curious ... would the STC be good for hot shot flyers as well?

Jim will answer, but I'd say highly unlikely. The IO-390 has the induction up front, which is where the turbo is located on the HotShot. It would also be entirely new STC, not just an "oh, let's bolt this back on here" kind of thing.
 
Re: Io-390 Stc

Re: Io-390 Stc

How many interested in an IO-390 STC for 112 and 112B?

What would you call it?

Super Commander Junior?

:D
 
Re: Io-390 Stc

Re: Io-390 Stc

Hi Alex,

Yes. Suffice it to say that the guys that did such a great job on airframe design did not have a clue how to do a powerplant!

Of note:

We dyno'd two 580's, one did 318, the other 319.
The IO-540 T4B5D is rated at 260, the T4B5 (B model engine) is 270.
For the 580, I figure we gained 60 by the book and 30 more by good engineering.

Jim
 
Re: Io-390 Stc

Re: Io-390 Stc

Hi Judi,

Good powerplant installation engineering makes a big difference! For the 390, I expect to gain 10 HP by the book and 20-30 more by good engineering. And keep in mind, this is assuming we are comparing to a brand new 360-C1D6 but there will never be any more of those. I think it all adds up to a fairly significant kick for the actual airplanes that get converted.

Jim
 
Re: Io-390 Stc

Re: Io-390 Stc

Hi Paul,

Sorry, I doubt there is any easy accomodation of the HS tech, but maybe we could approach Robin for his thoughts.

Jim
 
Re: Io-390 Stc

Re: Io-390 Stc

Jim,

I'll give you a call this week to discuss.

Bill
 
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