Engine upgrade

[VictorBravo]

Re: Engine upgrade

I owned a BC-12D with a non-electric 85 "bolted on". I have no idea how the annuals were signed off, because I never found a 337 or STC in the paperwork. To be honest, I had it annualled that way and just kept my mouth shut, and the IA didn't say anything either. He probably (mistakenly) assumed that an 85 was on the type certificate so that was that.

However I also realize this was probably not exactly up to FAA paperwork standards under the current rules.

As with probably everyone else here, I strongly support the Foundation making an argument for, and applying for a blanket approval, to bolt on an 85 non-electric with the minimum changes and no weight increase. This would allow Mr. Harer to still have a valid, valuable product to sell for the increased weight and avionics capability, but also allow people to get more power without tearing apart the entire front end of the airplane and requiring a new mount and cowl. The Foundation can also offer the FAA that it will bring a lot of "bootleg and barnyard" installations into conformity and thus offer an increase in safety. Perhaps the approval could be written so that existing installations must be inspected and signed off by an IA to conform before being approved under this new arrangement.

I support this type of proposal since it would make sense to the FAA, increase safety, and allow an improvement in aircraft performance without any big downside. AS LONG as the new approval also covers my pre-war Taylorcraft!!!!!!!!

Bill Berle

[Rich. Anderson]

Re: Engine upgrade

My field approval for installation of C-85-f cont. with a 337 was done in july of 1955. The only change made was the fuel injector had some rust so a carb. replaced it. Just a bolt on change to N96861 a 1946 BC12D.

It has been flying ever since with no fuel problems from the two wing tanks draining into the header nose tank. No mods to the struts or spars or fuel system. I did have the prop repitched from 74-43 to 74-42 for better mountain flying. The same prop I had on the 65 hp. I operated for a while out of dirt strips above 8000 feet elevation in the mornings and evenings during the summer. Many flights above the 10,000-12,000 foot altitude to clear the mountains. RBA in central Idaho

[fearofpavement]

Re: Engine upgrade

We received an STC for installing an O-200 on a BC-12D and there is no electric system or weight change. It was quite a process to go through and required the plane to go into the experimental category for a series of test flights and then was issued a normal Airworthiness Certificate. The exhaust is a somewhat homemade affair (no muffler) and I am not sure if the engine mount was modified or not. I was not involved in the modification and have been searching these forums to see what is involved in conversion to a Model 19 or F-19 but although this plane has many of the characteristics I haven't seen anything in the paperwork indicating a gross weight increase. I also don't know if the engine mount was changed. It doesn't look (to me) different from the average T-cart but must admit this is the only one I've flown since the 1970's.

[Dick Smith]

Re: Engine upgrade

Herman, do you have an STC just for that particular aircraft (Nxxxx) ? or do you have an STC that can be purchased and used by others? I can see a plane in my head...keep it light, already legal basis, a good strong 0-200, a long prop, an exhaust system going down and out, instead of crossing behind the engine mount, a B & C 20 amp alternator, a good first class lightweight battery, a lightweight starter if you can make it fit...really handy in a river, 2 landing lights for those dark, dark, Amazon nights if you ever found yourself coming home later than you should, and removable passenger seat, so you can put weight where you need and want it, and a really tight set of 1320's...tight since they will be low in the water once in a while and since you already own them...on second thought, get Baumann to sell you some floats at dealer cost, since you can be the South American rep! Where in Alaska did you live and operate? Dick

[barnstmr]

Re: Engine upgrade

Eric,
I think you're on the right track here. If you need any DER services, let me know. I will be glad to help. My authorization is in powerpolant installation.

[fearofpavement]

Re: Engine upgrade

We hold a "one time" STC for the O-200A install on a BC-12D. (SA00790AT) I think there are a lot of similarities to what we did and what Dutton did previously. The application was filed in June of 1995 and we received the STC in August of 1996. This is no small project to do one of these and I suppose if someone wanted to allow it to apply to additional aircraft the complications would be greater. We have put nearly 500 hours on the conversion and no related problems.

There is a "packet" the FAA provides that guides one through the process. I wasn't involved in this at the time but from after the fact knowledge it involved the application, getting an experimental type certificate issued, flying a test flight regime under strict conditions, having to have all the instruments and gauges calibrated and certified, then there were additional inspections and eventually we were issued a standard airworthiness certificate. (we received the STC and referenced that on a 337 for the actual approval on the plane.) New flight manual stuff required too.
Curiously, this #STC doesn't show up on the FAA website listing STC's not sure why. Am looking at the actual document as I type this. There is probably a hundred pages of "stuff" related to this endeavor. There were a lot of faxes from the FAA on thermal paper and much of that is barely legible.

[fearofpavement]

Re: Engine upgrade

Herman, do you have an STC just for that particular aircraft (Nxxxx) ? or do you have an STC that can be purchased and used by others? I can see a plane in my head...keep it light, already legal basis, a good strong 0-200, a long prop, an exhaust system going down and out, instead of crossing behind the engine mount, a B & C 20 amp alternator, a good first class lightweight battery, a lightweight starter if you can make it fit...really handy in a river, 2 landing lights for those dark, dark, Amazon nights if you ever found yourself coming home later than you should, and removable passenger seat, so you can put weight where you need and want it, and a really tight set of 1320's...tight since they will be low in the water once in a while and since you already own them...on second thought, get Baumann to sell you some floats at dealer cost, since you can be the South American rep! Where in Alaska did you live and operate? Dick

The STC was for one plane. I flew out of Skagway. (wheels) Most of my float flying was in Louisiana doing oil related stuff and a bit in Brazil and Michigan.

[barnstmr]

Re: Engine upgrade

Eric,
Just checking back in. How is your STC project coming along? Can you give us an update?

[tim]

Re: Engine upgrade

yes u can a firend of mine who has the stc for the sky light is a t-craft expert and i told him what im doing with my plane he told me that i can put a c85 elec on my plane with a c65 engine mount and if u want more room u can modify the fire wall to clear and if u want to get a hold of him i can give u his number

[JohnH]

Re: Engine upgrade

Tim,
I would be interested in talking to your friend. Can you send me his phone number?
Thanks,
John

[Sloanlow]

Re: Engine upgrade

x cuse me but i have a question! UHHHHM, ah I have a 1938 A, with a 65 hp STC, is there a way that I can ah, get a little more horse power in the model A.

Thanks
Jim

PS its a lot warmer in these parts yellow duck.

[Acroeric]

Re: Engine upgrade

I backed off th eSTC due to being so busy with other stuff. I still think we should go for it- I just do not have much time.

If we could find a really old 337 (before 1954 I think) they can be used as APPROVED DATA- In other words - it is good on multiple installations without FAA Approval.

Any IA's want to double check my date? 1954 seems right but I may be wrong.

[Garry Crookham]

Re: Engine upgrade

Eric:
Per AC 65-19: 337's approved in 1955 or earlier may be used as approved data.

Garry Crookham
Tulsa

[Acroeric]

Re: Engine upgrade

Thanks Gary.. . . . .I am on dial up and that AC would have taken an hour to open!

Rich Anderson- if you have a copy of your old 337 it is approved data and it can be used on other planes.

[Ragwing nut]

Re: Engine upgrade

Why would anything more than a 337 be required to install a C-85-8? The installation is already approved on the TC data sheet as a BC12D-85 and is on the same TC data sheet A-696 as the BC12D. I have done 2 engine upgrades using the TC data sheet as approved data on the 337's. Unfortunately a lot of the approval problems are regional and every office acts as an independant agency. We have are issues here too, but they are not as bad as others I know of.

Mike