Does anyone have or know of a Piper J-4A on wheels with a field approved C-85 engine? I'm looking for a 337 form that has coverd this conversion. They are approved for seaplane in the J4 type certificate, but not for landplane.
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Does anyone have or know of a Piper J-4A on wheels with a field approved C-85 engine? I'm looking for a 337 form that has coverd this conversion. They are approved for seaplane in the J4 type certificate, but not for landplane.
Post this over on j3-cub.com. There are a few guys that have j4s there. Also you could try the cub club. www.cub-club.com
Keith
This is how I found the pre Oct. 1955 Field Approvals that are considered approved data when I did my Vagabond. Go to www.landings.com and search for all J-4's. It will show what engine is installed. Write down N-number and serial number of every one with a C85. Go to www.faa.gov and request the records CD for each at a $10.00 price per CD. A week later you get the CD's in the mail, look for a 337 dated prior to October 1, 1955. It should also carry a CAA stamp. Get with your IA or FAA inspector and use that 337 as approved data for your Field Approval. Not really hard, just takes a little time.
Dave
Just be warned about the belief that pre-1955 337's are automatically recognized by the FAA as approved data. I tried to use a pre-1955 337 when installing PA-12 wings on my Piper J5A. The FAA would not recognize as approved data a 337 I found using the process outlined in the previous post. Even after I gave them a photocopy of a letter on Piper letterhead from Piper's chief Engineer that PA-12 and J5A wings were interchangeable, the FAA still would not approve it. I needed to obtain a one-time STC for the alteration. It was alot of work and took nearly 3 years. Your best chance might be to find a good powerplant DER to go through the paperwork hassle. Good luck!
-Joel Marketello
I looked up the Aircraft Specification A-703 and I do not see where the C-85 is not allowed on a J4(A) land plane.
The C-85-12 is allowed as an optional engine per item 301(b) (4). I can not find any reference to just being approved on a seaplane. It appears to me all one needs to do is install the engine and make a make a log entry and revise weight and balance and equipment list. No 337 required as this is a minor alteration because it is listed in the A/C Specs. as an option.
I agree. According to the TCDS the C-85-12 is listed as one of the engines approved on the J-4A.
The regulations say that they may be used as aproved data. I wonder if the problem is at a certain FSDO in Texas. I've heard some horror stories out of that office including grounding an airplane that had a later model of the engine that came in it that had been approved by the Atlanta FSDO 12 years previously. The inspector said the Atlanta FSDO made a mistake and you better not fly that airplane, when shown the approval paperwork.
(OP) My problem is that I am taking a C-85 from a Cessna 140 including the mufflers and metal propeller & if possible would like to get a field approval (337) on the swap. The metal propeller isn't approved for a J4 w a C-85.
In so doing I have also replaced the Bendix carburetor with a Marvel Schebler unit to handle the J4A's cowl tank's low head pressure. I now understand that Al Ziebell at Oshkosh has done a number if J4 rebuilds. Unfortunately he died last October.
THX for the inputs guys!
nrpeterson - I would be glad to take a look at your project and consider for DER approval. It really sounds like you only need approval of the prop and exhaust and perhaps something about your carburetor, etc.... but NOT approval to install the engine. email me at barnstmr@aol.com.
If all above is true, the C85 engine is already approved on the airplane. So maybe that part was unclear to FSDO and could explain their rejecting your request.
The FAA FSDO troubles everyone is talking about has to do with the FAA Order 8900.1. Volume 4 Chapter 9. This order has a list of types of alterations that can be approved as a field approval as opposed to those that must be approved as an STC. For example: It says engine changes over 10% increase in horsepower require an STC. This was not always the gospel. But now it is ORDERED as such. FSDO inspectors are required to follow the order. This document is being continually revised with less and less authority given to FSDO inspectors to issue field approvals. Also, it has made a lot of FSDO inspectors gun-shy about doing any sort of field approvals that could be considered a borderline changes close to the STC realm. The bureaucratic thumb is forever tightening. To give you perspective... in the 1950s, the first TWIN NAVION was converted from a single to a twin on a 337 - no STC.
There are numerous "one-time STC's" to put a C-85 in my Vagabond but my local FSDO won't allow that change now. They suggested I hang an A-65 (an STC is available for that) and then they could approve upgrade to a C-85. From what I've experienced, changes are mostly an exercise in patience with a system that needs more familiarity with older aircraft. Wish we could at least "shop" FSDO's.Quote:
Originally Posted by D.grimm
Update on my J4A - The local GADO office has been cooperative but it turns out there is a nasty AD on the Hanlon Wilson mufflers that I was planning to use. AD calls for 25 hr inspections for cracks - and no one is permitted to fix them. I decided to bite the bullet & now installing a C120/140/150 muffler system. Trouble is the nose bowl has some interferences so it is chop time to my cowl. But the muffler system is a much better package & I don't regret having to do it. The IA said that OK City FAA engineering would be very leary of any engine swap schemes that used that old muffler scheme.
Dawley Aviation rebuilt a Hanlon Wilson system for me. It was on a 7AC. They had some trouble though finding the seals that surround the stack on its way into the heat muff. Been a couple of years so they may not do that any more.
That sounds like a different muffler configuration than my old H-W mufflers. The H-Ws I have are one welded piece of stainless from the exhaust flange thru to the tail pipe. A second stainless stamped pair uses a number of #10 screws to hold and form the heat muff outside. The whole assembly resonates laterally on the engine with very low damping. One side was ~66 Hz and the other at ~105 Hz. I figured it would only be a short time until something fatigue cracked.
interesting topic, here's in excerpt from the 8900, and why your wings were denied possibly?
"A. Previously Approved Data for an Alteration to a Specific Aircraft. Data that isapproved by the FAA to substantiate an alteration for one aircraft is applicable only to thataircraft described in block 1 of FAA Form 337. Such data developed for the altered product isconsidered acceptable data and may be applied as a basis for developing approved dataapplicable to alterations on another aircraft involving equipment of the same make and model.The make and model of the aircraft may be different if the installation is similar."
Also, there's a nice flow chart in the chapter. Field Approval vs STC is based on is it a Major Alteration (based on CFR43 App A) or a Design Change (based on CFR 21.93). That seems to be where the discussion lies between what can get a field approval vs what needs STC.