180 legs

[fly dakota]

wondering about stc and someone who has done this mod changed to 180 legs i mean

[blueldr]

What is it that you want to know?
The STC is now required to make the installation "legal".
The earliest type 180 legs will raise the nose a few inches.
The mid type legs will also have the axle line moved forward 3 3/4" and will add very slightly to the tail wheel load.
The late type legs are also common with the C-185 and are heavier duty.
They will all bolt in to the C-170 box, but may require modification of the locking wedges.
They will all be noticeably stiffer than C-170 gear and weigh a little more requireing a possible weight and balance change.

[fly dakota]

wondering if this can be done with just a log book entry or if there is more to it then that thanx

[blueldr]

After about fifty years of this modification being done rather simply, the FUZZ, in their infinite wisdom, granted someone the STC that it now requires.

[Bruce Fenstermacher]

Saying the same thing as BL but differently.

Today the FAA does not like to make individual approvals preferring (REQUIRING) people to use available STCs if one is available. If no STC is available they prefer (REQUIRE it seems) for a person to go through the STC approval process even to get an approval for one plane.

A lot depends on the FSDO management you are working with, the Safety Inspectors in that FSDO and their relationship with your IA and this can all be related to the area of the country you live in. It is entirely possible you could ask for and receive a one time approval to install 180 gear legs just by asking as it has been done for nearly 60 years. But if you want to guarantee the installation approval, buy the STC.

[minton]

Having done it field approval way for years and now the newer requirements of AC 210 (Application for Field Approval) It is now more cost effective to buy the STC if you have to pay your AI by the hour for his time involved in the field approval process.

The AC 210 application paperwork requires half a days typing and research. Then the meetings with FAA. Then the wait to see if you are going to get lucky and win approval on the first try. It can add up to 6-8 man hours just for the FAA stamp on your 337.

STC and 2-4 hours installation labor and you are done.

STC is the best way to go.

[blueldr]

I cannot help but disagree with having to pay the sometimes excessive cost for a STC for a item that has been done for many,many years and with many,many sample 337s to attest for it. The Installation of the C-180 gear legs on a C-170 is a perfect example. After all these years, why should some guy get a "permit' to allow you to do a job that has been done for years.
I tend to get the idea that the FAA, due to their "dumbing down" program, is afraid that their aircraft maintenance overseers are too incompetent to do the things that were historically done by their predecessors.

[fly dakota]

thanx for info i have found the stc# sao1756ny the holder is QCR Aviation in canada have googled them but no luck with that

[jrenwick]

It's the same as if the patent office were to grant a patent for something that's historically common practice. If an STC were like a patent, it could be challenged in court, and in a case like this, it probably wouldn't stand.

[GAHorn]

wondering if this can be done with just a log book entry or if there is more to it then that thanx

No. A "logbook entry" only would imply this to be a "minor alteration" which it is NOT, based upon the definitions you can find in FAR 43.
Eric LeClerque, is listed elswhere in these forums and a former member, who owns and sells this STC quite reasonably.

[blueldr]

I don't give a big rats a-- how reasonable the STC is. Why should they require a STC after fifty years of previous use and experience?

I've heard that the STC is $200.00. What justifies that for an action that has been in common use for all those years?
Are all those airplanes that were "grandfathered in" prior to the issuance of the STC now unsafe?

[HA]

I hear you BL, the company I work for has been modifying airpanes for cloud seeding and research work for 40 years

specifically we've been running C90 King Airs with certain mods for about 10 years, suddenly the Fargo FSDO asked a question to Chicago Region FAA and just like that we are required to do the exact same mods under an STC. that was a year and a half ago, next week I'll be doing the test flights that should be almost the last step before we get our STC for the mods we'd been doing and flying for years. hundreds of thousands of $$ later we'll be allowed to perform the same mods as before, with over a year and a half of lost business in between.

I'm sure the STC airplanes will be ever so much safer than the other airplanes we have, that are still legal to use in their modified statre by the way because they're grandfathered in. what a crock.

[GAHorn]

Not a defense of what otherwise should be common-sense:

I appreciate the frustration of this seemingly-ridiculous matter but....the problem is one of execution. In the distant-past, it was acceptable that if YOU changed your airplane and could get the "FUZZ" (to borrow a term) to "OK" it... then I could do something similar and tell a different fuzzy-guy "Hey! ... They let DICK do it!" ...and he'd have to cave-in and let me do that something-similar to my airplane too.
However, just because YOU have a "field approval" in which your aircraft had it's cabin-heat system changed to the later "post-'53" system (or whatever other modification you might wish to mention) .... doesn't always translate to an identically-executed modification of another airplane using your basis-of-approval. (YOU may have used genuine parts from a salvage airplane and altered your airplane exactly like Cessna later mfr'd it...or you may have merely made up some sheet-metal boxes and accomplished a similarly-functioning system. Or you may have used papier-mache' and PVC plumbing-pipe that releases cyanide-gas when it is heated escessively. The fact you used rubber inner-tubing for gasketing makes for dangerous cabin fire fumes, or perhaps your hookup to your home-made "Y" fitting to your carb-heat box allows gasoline fumes to enter the cabin when your carb-float/needle sticks/fails.... those conditions having never been looked at by anyone even remotely-qualified to design such a system.... make the first mod dangerous, and without documentation, allows every other ad-hoc mod based upon it to be equally or more so.
And.... the FSDO/GADO guy who approved yours had neither the requisite aeronautical-engineering experience nor the detailed-description/documentation of such a qualified-person to attest to the safety/function of that first mod...much less that of the second, seemingly-similar but actually different modification. (Yet he was personally "on the hook" for any fatalities that might result.)

This is the situation that has caused FAA to re-design the approval-basis system.

In theory at least, STC's must be properly engineered/approved/documented and that's why they are superior in most cases to field approvals. The installation and completion/testing of the mod must be properly described so as to assure that each subsequent mod is completed in an IDENTICAL manner as the approved one.

Think of the old field-approvals as a "one time STC, which had the strong-possibility of being designed and tested and approved by the undocumented/unqualified" using materials which may have never been properly vetted for applicability.

I admit that using salvage parts from a Cessna to (essentially) modify another airplane in a well-known manner seems simple enough. But without the details/documentation of which parts, what pre-disposed conditions and parts-testing, and what methods/techniques are to be used in making the alteration, then even such a simple matter as this conversion does not meet the uniformity required when individual airplanes are cobbled together from the junk yard.

Frustrating, but the process needed amending. Don't like having to buy an existing STC? Fine. Do your own....you can either provide a basis for approval and get a "one time STC/field approval" ...or you can do it so you can pass it along for others to use. Either way it is YOU who decides what your efforts are worth. (Thank you Ron Massicot for being so generous as to virtually give your work-product to the rest of us.)

[ron74887]

Well, after George actually accused me of being economically challanged for selling the STC at the low end he now says THANKS. Now having said that--I still have pretty good relations with the FUZZ (have all their email addresses still on the computer) and if I can get a bunch of copies of the 337's I will attempt to get an STC issued in the Associations name. Your 337's should have gear leg numbers and some installation procedure. I would need one for each model 170 A,B. If you have them let me know. Emailor call me and you can fax it to me. There can be more than one HOLDER for a given STC application. BRUCE did you see this coming!!!! might need help in writing the procedure. Even though he's a YANK he can write a pretty good procedure (he puts it in English inlieu of Cajun). He helped tremendously on the B engine in the 170's.
I don't want to step on anyone's toes but is the holder a member?

BL if we only get $ 75 for and engine we can do alot for the gear leg that is up to your board!!!!
Ron

[minton]

I cannot help but disagree with having to pay the sometimes excessive cost for a STC for a item that has been done for many,many years and with many,many sample 337s to attest for it. The Installation of the C-180 gear legs on a C-170 is a perfect example. After all these years, why should some guy get a "permit' to allow you to do a job that has been done for years.
I tend to get the idea that the FAA, due to their "dumbing down" program, is afraid that their aircraft maintenance overseers are too incompetent to do the things that were historically done by their predecessors.

Just scared of loosing their feathered nest