New Taylorcraft owner !!!

[Falcon10]

This is my first post on the forum. I recently purchased a 1934 BC. I am trying to track down some information, any help would be greatly appreciated.
There are several modifactions that have been done without any paperwork.
the ones that worry me are the addition of Hyd brakes and the instilation of a C85-12. It was certified with a C-75-12 in 1953. But it had this 85 hp engine installed recently. From the research done here on the available STC'S I dont think that I can get the 85 approved. Can I just change the Jetting in the carb to bring it back to a 75 ?. It also is swinging a CM7150. It seems to be over pitched ? what pitch would be best If I bring it down to a 75hp.
Any opinion on leaving it a 85hp and placarding a rpm restriction to keep it legal ? My trim is slipping any ideas ? Thanks in advance.
Jim.

[VictorBravo]

Re: New Taylorcraft owner !!!

This is my first post on the forum. I recently purchased a 1934 BC. I am trying to track down some information, any help would be greatly appreciated.
There are several modifactions that have been done without any paperwork.
the ones that worry me are the addition of Hyd brakes and the instilation of a C85-12. It was certified with a C-75-12 in 1953. But it had this 85 hp engine installed recently. From the research done here on the available STC'S I dont think that I can get the 85 approved. Can I just change the Jetting in the carb to bring it back to a 75 ?. It also is swinging a CM7150. It seems to be over pitched ? what pitch would be best If I bring it down to a 75hp.
Any opinion on leaving it a 85hp and placarding a rpm restriction to keep it legal ? My trim is slipping any ideas ? Thanks in advance.
Jim.

Jim, you have a rare bird indeed. There were no Taylorcrafts produced in 1934, and the BC model came out in 1938 at the earliest.

You didn't happen to buy the plane from a guy named David Guntly did you? Somewhere in the Dakotas or Wisconsin?? That airplane has been for sale off and on for a while and reportedly has several things that need to be addressed in terms of making everything legal. It originally had an O-200 bolted on illegally, and I heard a rumor that he took off the O-200 because the FAA wouldn't buy it.

Regardless....

First, you need to figure out what type of modifications were done to allow the installation of the C-75. Did they just bolt it on, or did they change anything on the airplane, in the spars, the fuel line, the spar fittings, etc. You need to see exactly on what engineering basis the FAA allowed the change.

You CAN certainly have an 85 engine approved in a Taylorcraft model B or BC. there is an STC available and several "field approvals" you could base your own field approval on.

The 71CM50 might already have been twisted back to a lower pitch and perhaps not re-stamped. If your airplane flies properly and has adequate takeoff performance with two people and full fuel, then leave it for the time being. You can deal with having the prop re-pitched or inspected or recertified once all the larger problems are sorted out.

DO NOT screw around with the carburetor jets if the airplane is running properly now. You will find it possible to do a field approval for the C-85 and no airframe modifications, creating a BC-12-85, with no increase in gross weight. I believe there are several such field approvals in the hands of some members of this Forum. You might persuade one of them to allow you to borrow it.

Placing any operational restrictions, such as RPM or anything else, sounds like it will be more trouble than it's worth. Even though it makes sense mechanically, and the 75/85 engine weight difference is almost nil, the FAA will probably not make it as easy as it should be. Further, you don't want to lose the benefit of having an 85 on your airplane.

Look in the logbooks. You are looking for the word Harer, or the word Gilberti. or the STC number SA1-210. If you have this STC SA1-210 installed, or the old "Gilberti STC" installed, you can bolt the 85 right on. Or, look in the logbooks for the phrase "11/16 spar bushings".

Look on the airplane where the struts bolt underneath the wings. If the metal fittings have little 2 by 3 inch rectangular plates welded on them, that is a good sign.

While you're at the plane, look at the data plate, and look closely at the upper door hinge tabs where they are welded onto the fuselage. There should be a number stamped into that steel hinge tab. Write that number down, and then see if it matches the serial number on the data plate. Then see if ANY of those numbers match the serial number on the airplane's paperwork.

Now look at the side of the fuselage under the stabilizer. Is there a little movable flipper that rotates (the old style trim tab)? Is there a little crank on the cabin roof above the instrument panel, or is there a thumb sized lever under the front edge of the pilot's seat? The little flipper and thumb size lever were on the Taylorcraft up until mid 1941. The crank above the panel was put on just before the war and it operated a standard trim tab in the back of the elevator.

Hydraulic brakes.... that could be very good news or very bad news. If there is no paperwork at all it is bad news, and if there are Cessna style toe brakes on the rudder pedals it might be very bad news. Sit in the airplane and move the control wheel back and forth. Does the big steel thing under the instrument panel attached to the control wheel bang into your feet? Can you move the rudder pedals all the way back and forth without your feet smacking that steel yoke? You need to sit the former owner down and have him come clean on where all the modifications came from. You need to find out what type of wheels and brakes are on the airplane, what type of master cylinders, etc. Some people have field approvals on hydraulic brakes, and if your airplane is close enough to one of those field approvals then you might get legalized with a few minor modifications and a paperwork shuffle.

But first, more than anything, you need to figure out what you have bought. Did you buy a real factory built Taylorcraft, or did someone start with a wrecked airplane and build an experimental out of it. Did you buy a pre-war airplane or a post war airplane?

Bill

[DannyDot]

Re: New Taylorcraft owner !!!

Try getting the records from the FAA at:

https://amsrvs.registry.faa.gov/e.gov/ND/AirRecordsND.asp

This will tell you what has been filed with the FAA on your airplane.

[Falcon10]

Re: New Taylorcraft owner !!!

Bill:
Thanks for the Great info!!. She is a 1939. ( typo on the 1934) The logs are pretty complete. Her serial # is 1293. N22646 .I do not see any Harer or gilberti stc. However the fuel system was modified and a fuel flow test was done, a test run for cooling was completed and endorsed by the faa. the aworthiness cert changed to reflect the 75 hp. I dont see any data in the logs to reflect a mod to the spar or attach fittings. I will check out the airplane when I get back in town. The Brakes are heel type with a remote res. It is a pretty clean instilation. No intereference with flight controls. I would rather go back to the Shinns than have to deal with the FAA! The Hyd brakes dont seem to be any better than the original anyway. The fuse appears to be the correct one. I can see a slight corrosion repair that is recorded in the logs. I Dont really want a gross weight increase. I just dont want the fed's to ground me. She was made with only left side door. the second wes added later and approved. but I dont see anything regarding the D windows. Do the wings have to be uncoverd to install the apropriate stc?? She flys well. with the current prop. 500-600 fpm 18 gals fuel and two on board at 1000feet alt
It would be great if someone could post a pic of the mods to strut attach fittings so I can compair when I return to home. Thanks in advance.
Jim.

[Robert Lees]

Re: New Taylorcraft owner !!!

Here is a picture of the plates welded to the strut fittings.

Rob

[Dano"T"]

Re: New Taylorcraft owner !!!

You do not need the gross weight increase to get an 85 approved. There is documentation available on from the foundation...or PM me and I'll send you what you need. You can buy the Harer STC for $250 and have the fuel mods inspected for complience....then just submitt a 337 stating that the fuel mods were done but the wing mods were omitted...gross remains 1200....or 1150 in your case.....unless the wing mods were already done....then you'll be all set.

[VictorBravo]

Re: New Taylorcraft owner !!!

Bill:
However the fuel system was modified and a fuel flow test was done, a test run for cooling was completed and endorsed by the faa.

The Brakes are heel type with a remote res. It is a pretty clean instilation. No intereference with flight controls.

I just dont want the fed's to ground me.

She was made with only left side door. the second wes added later and approved. but I dont see anything regarding the D windows.

Do the wings have to be uncoverd to install the apropriate stc??

First, if you don't want the feds to ground you, one of the most effective methods these days is to (unfortunately) limit the amount of information they get. This is their own doing, by abandoning common sense, letting many of the gray haired old guys who really loved aviaiton go, and a change in their federal mandate to no longer actively "promote" aviation.

What was modified in the fuel system? All you really need to do for the 85 horse engine is to go up to the -6 size fuel line from the gascolator to the carburetor, and that is even suspect. But it costs very little do do, and it goves you an opportunity to install a new firesleeved hose for safety.

Can you tell me what cooling tests were done? I'd surely like to know what test and what result was shown.

To be brutally honest I would recommend you FORGET about the brake installation. If your IA looks at it and asks where it came from, you respond "Gee Whiz, Sparky, the old timers at the airport tell me the Taylorcraft is famous for having little heel brakes... they sure is different than the ones on the Cessna 150 I learned to fly in???... but I'll sure fill up them little reservoirs whenever they's a little low if you'll just move on to talkin' about somethin' else!"

Now before the IA's all show up at my front door with torches like a bad Frankenstein movie, simmer down, I personally think that if push comes to shove an experienced IA should agree that a cleanly designed and executed hydraulic brake installation on an airplane that was certified WITHOUT brakes in the first palce is a MINOR alteration and should be viewed as such. 'specially if it looks like one of the drawings in AC 43.12.

The door and the D windows are a non-issue. One or both doors are on the type certificate and are more or less interchangable. No new-age FAA inspector will even think twice, and any old inspector knows that the T-craft "Ace" models with one door have all been upgraded to two doors. Total non-issue, forget about it. Same with the D windows. It's non structural and they're on the ATC.

The wings do not have to be un-covered to do the STC. You will have to do some patching, but you can minimize the patching if you're clever. An 8 inch square removed from the lower surface of the wing about 6 inches outboard of the root rib is enough for just removing the front spar fittings... it will be tight quarters but it can be done. Drilling out the holes for the larger bushings will be a trick, but I believe you can do it with a 90 degree drill attachment.

I want to go on record as saying the following is MY PERSONAL PREFERENCE and this is in CONFLICT with the preferences of others on this forum, as well as being in conflict with the Harer STC.

If you do the Harer STC, I recommend bonding the new 11/16" diameter phenolic bushings into the spars with an approved structural adhesive. I don't give a damn what any engineers say, or any IA's, or Mr. Harer, or Mr. Gilberti, or the Administrator, or anyone else. Under extreme load, if the bushings are NOT glued in then they become a "splitting wedge" trying to split the spars along the grain. If they ARE glued, they OPPOSE splitting the spar along the grain. Granted the plywood reinforcement plates are there to hold against these splits, but there is no justification whatsoever to make the plywood work that hard after 70 years. Anywhere you can REMOVE a potential failure mode is good. Gluing in the doublers makes a spar root that is stronger than without them being glued in. If you ever need to remove them, you will have to drill them out, but that is a small price to pay to increase safety even a little.

Just my opinion as an old broken down model airplane builder

[Dano"T"]

Re: New Taylorcraft owner !!!

What was modified in the fuel system? All you really need to do for the 85 horse engine is to go up to the -6 size fuel line from the gascolator to the carburetor, and that is even suspect. But it costs very little do do, and it goves you an opportunity to install a new firesleeved hose for safety.

You need to replace the gascolator to one that accepts 3/8" fuel line ( you can't just put a reducer from 3/8" to 1/4") and then replace the fuel line AND main shutoff valve to a 3/8".

[Falcon10]

Re: New Taylorcraft owner !!!

here is what I have on the C75 install

[Falcon10]

Re: New Taylorcraft owner !!!

more data regarding the cooling test.