Trouble with C-175 wing 337

jim4435B · Post by **jim4435B** » Fri Mar 07, 2003 6:44 pm

Trouble right here in River City. I was going to install C-175 wings on my '55B model using the Association's 337. However; the local FSDO (ABQ) and OKC say they will not aprove my applacation for 337 and that I should go the STC route using a DER and come up with all the required engineering to prove this is a safe thing to do. I know there are many 170's out there with C-175 and L-19 wings on them. Does any one have an idea as to how many are flying with these other wings installed on them. Has there be any trouble in the field with the use of C-175 wings on the C-170. For now the wings are in the corner of the hanger and maybe for sale. HELP!!!

zero.one.victor · Post by **zero.one.victor** » Fri Mar 07, 2003 7:39 pm

I wonder if it might be easier to get approval for installing 175 tanks in replacement "170B wings"? (wink-wink!)
Or it might be easiest to just install "170B wings" (again,wink-wink!) ,with no notation of bigger tanks. What's the difference,besides 8 gallons or so of tankage?
I'm not a big one for lying,but this is a pretty stupid thing for the Feds to get problematic about.If anything,the 175 wings are probably better than 170 wings as the 175 is a heavier airplane.And this mod has been done to quite a few 170's already. In this case,ignorance may be bliss.

Eric

Fri Mar 07, 2003 11:01 pm

I have L-19 wings on an A model. As part of the approval there was letter from Cessna outlining what wings would be appropriate. I'd contact Cessna with you wing part numbers and I understand they will then issue a letter in favor of your wing installation for the approval.

Email me privately and I'll send you copies of my paperwork including the letter from Cessna outlining the wing replacment proceedure.

What your probably running into is the infamous change 15 which has basically stopped all field approvals. It is interesting reading.

With all the documentation available and Cessna cooperation the DER route might not be that hard.

wa4jr · Post by **wa4jr** » Sat Mar 08, 2003 6:17 pm

I'm with Eric on this issue. Those wings in your hangar...take a look at them very closely...thats what I thought....they are INDEED C-170B wings AREN'T they. Proceed with the installation of your used C-170B wings and enjoy! Also enjoy the fact that the tanks seem to be taking more fuel than some other 170Bs and plan your load accordingly. If roadblocks are intentionally placed in your way...just go around them!

Post by **GAHorn** » Sat Mar 15, 2003 5:55 pm

Find a different inspector, or educate the one you've found. The 175 wings are acceptable replacements on the 170B. Cessna engineering has issued approval for this.
They are not simple exchanges, however. The fuel indication system must be allowed for. The 175 had electric indicators.
Change 15 still allows field approvals, you just have to include "Instructions for continued airworthiness." This should be simple. Most of the pages are N/A. Fill out the forms, and refer to the Cessna Service Manual, 100 Series, 1962 and prior.

zero.one.victor · Post by **zero.one.victor** » Sat Mar 15, 2003 10:52 pm

Jim,have your inspector call George,he'll straighten him out!

Eric

Jon Stark · Post by **Jon Stark** » Sun Mar 23, 2003 6:38 pm

Does this installation conform to the original type certificate or to any approved supplements thereto? If these wings are in the Illustrated Parts List or if there is a Cessna Service Letter allowing their installation you're in with a logbook entry.

If you need to use acceptable data that then needs to be approved by the Feds then find all the like 337s you can get your hands on tto support your case. You'll need to compose ICA or Instructions for Continued Airworthiness (very simple to do) This then goes to the ACO (Aircraft Certification Office) for their concurrance. If the data package is complete then they will concur and return it to your FSDO for approval. You may have to go back and forth a few times and ACO in and out baskets move slowly.

If you can find a DER for less than the price of the wings to go thru your data he can approve it or come up with his own. He will provide you with FAA form 8110-3 for the data package which means it is approved. Then you give it to the Feds along with your returned-to-service 337 and try not to thumb your nose within eyesight.

jon

jim4435B · Post by **jim4435B** » Mon Mar 24, 2003 5:45 am

My local FSDO isn't buying into any of this. If I used the standard 172 wings and tanks the Cessna letter would have been helpful. Using the 172-175, 26 gallon long range tanks and wings with the different wing rib and extra fuel that's a no go. They didn't like any of the 337's the other 170 owners or IAs have used in the past. They also didn't like the wording for return to service on the 337 apt that was run past them at the begining of this project.

I called Del-Air in Porterville, CA on Friday to see if he had any ideas. Del-Air has been working on a STC to use early model 172 long range wings and tanks on the A and B model 170. The part numbers are the same as the wings in the corner of my hangar. The current plan (HOPE) is that Del-Air can get an approved STC soon.

This isn't over just yet. Jim 4435B

Post by **Bruce Fenstermacher** » Mon Mar 24, 2003 1:27 pm

Jim, I'm not sure if the "Cessna Letter" you refer is from my records or not as I've sent it to a lot of people. What I understand is that you should contact Cessna and hopefully the gentleman that generated that letter. He told me that if the wings met Cessna criteria outlined in "the letter" he would generate a favorable letter specifically for your wings and installation. That should be enough for the FAA after all who should know better that the manufacturer. (Oh that makes to much sense

)

jim4435B · Post by **jim4435B** » Tue Mar 25, 2003 3:22 am

Bruce, I tried to get Cessna to provide a letter like yours with the part numbers for the wings/tanks that I had planned to use showing the SN of my 170. The reply was we sent you the generic Cessna letter and thats all we are going to do for you. The gentleman that sent you your letter retired about a year ago. Jim4435B

Post by **Bruce Fenstermacher** » Tue Mar 25, 2003 2:06 pm

That's to bad.

Those wings you have in the hanger have are looking more and more like stock 170 wings to me.

wa4jr · Post by **wa4jr** » Thu Mar 27, 2003 12:35 am

I agree with Bruce. As the WX warms up and good flying weather returns...those wings are looking more and more like stock 170B wings aren't they. Don't try to swim across the Pacific if there is an easier way! At this point, with your local FSDO playing dirty pool/stupid, then you just have to get down to work and blow smoke at them! Change the numbers if you have to in order to make them match with 170B wing numbers...use the numbers off your old wings. At this point, you KNOW the wings are compatible and SAFE. The larger tanks will have NO bearing on the performance of the wing on the aircraft with the exception of the added weight when topped off. I like to be honest and do the right thing whenever possible...but sounds like your FSDO is not at all interested in fostering an atmosphere in which you can be honest..... The old saying that honesty is always the best policy is not always true when dealing with certain entities

zero.one.victor · Post by **zero.one.victor** » Thu Mar 27, 2003 6:18 pm

In some situations like this,the Bill Clinton "don't ask--don't tell" policy seems very appropriate.

Eric

DHeal · Post by **DHeal** » Thu Mar 27, 2003 8:15 pm

Don't you guys worry about having your high-cost liability/hull insurance proceeds cancelled when your insurance company discovers after the accident that the plane is not legal/properly certificated? The insurance company would just love to discover such a nonconformance item. -- David

Thu Mar 27, 2003 10:04 pm

Yes David I might if the wings were not 170 wings.

The International Cessna 170 Association

Trouble with C-175 wing 337

Trouble with C-175 wing 337

[b]Litmus test[/b]