The International Cessna^® 170 Association

I am working on a 1950 170A that was brought to my attention after a purchase. The A/C had a minor issue while on the way home. I corrected the issue and signed it off and sent them on their way. However, the next day during preflight the pilot called and said that he only had 1 (one) flap extend. The flap cable was improperly installed and subsequently from flexing it finally broke. The A/C was due for an annual inspection by month's end and I reluctantly agreed to take it on. (reluctantly=back logged with other A/C, etc.). I began the inspection and of course found minor and some not so minor issues. However, there is 1 glaring issue that I would entertain input from the forum on. The installation of a new instrument panel and sub panel to accommodate a radio stack. According to the 337, dated way back to 1988, the work done was thus listed on the 337:

1. Removed original instrument panel and sub-panel.
2. Installed new instrument panel per drwg. ARG 170P-6001
3. Installed new glare shield per STC SA152NW
4. Removed the original Cessna "T" style yoke p/n 411-2 per STC SA152NW
21-3 and replaced with Cessna "Y" control yoke p/n 0460128-1.
5. Shortened aileron cables using Nicopress method per AC 43.13-1A chapter 4, para 196 and attached to control yoke with AN 115-21 shakles.
6. Rigged the ailerons to manufacturers specifications and checked travel limits.
7. Aircraft weighed and C of C computed and entered into the logbooks.
8. The above work was done in accordance with STC SA152NW and AC 43.13-1A

As I read as much as possible the owner of the STC SA152NW was a member of the TIC170A. Indications are that the STC involved only a glare shield? All the paperwork the owner has is a copy of the STC cover letter. The same information you can get off the FAA’s website. I know this rather lengthy, but I have to describe a picture of this installation the best I can. So to start,

The control column is NOT a Y control yoke as mentioned. It is not the original either and the p/n should have been written down as 0411221 (mistyped and left off some digits?). I have the p/n written down of the currently installled column, unfortunately it’s in my toolbox at the hanger. I do remember it is a control column from a 172 later model. Next problem, the Nicopressed splices bump the pulleys on the control column and the ailerons do not hit the stops. Anyone ever have such an ordeal? Am I missing something? It is a real head scratcher. My guess is that someone has installed the current column, made Nicopress splices and DID NOT document the work. The AN115-21 shackles are not present either.

Any insights would be welcome!

Just off-hand I’d mention that not many STC’s apply solely to “removal” of items…. but even if so,…the concern is Less of what was removed…and more importantly about what was “installed”…as to basis of approval.
There are a number of stories about 170s which had their “T” yoke removed and either modified or replaced by a “Y” yoke to accommodate center-stack radios. Many of these stories end-up in a fog-cloud of “not approved” or ignored….hoping no one as knowledgeable as yourself will notice.

It sounds as if someone owns an airplane with unapproved flight control modifications and, as inspector, you are doing the moral-thing in questioning it. I hope there are some Members and Participants here who can help with solutions they have found tolerable.

@gahorn, thanks that is exactly what I was hoping for. The broken flap cable (improperly installed) was a red flag. When you start finding "weird" things you start looking a lot closer.

STC SA152NW applies to the installation of R. J. Schroers’ glare shield.

It would be helpful if someone can upload the details on the STC to this site.

The 172 control column length must be modified to fit a 170. There should be plenty of run available below the centre pulley for the direct cables to have full deflection of the ailerons without fouling so it may just be a rigging issue or the wrong cable lengths installed.

The owner is very fortunate his flap cable broke while safely on the ground. Given your description of the primary flight controls, he may have had a serious problem if that occurred during a low level landing approach.

Your description of this airplane raises red flags. My advice is to carefully document discrepancies that indicate an improperly altered condition or other defects and present these to the owner. If possible, also a recommendation for corrective action that would allow you to complete an annual inspection and return to service. Then it is up to the owner on how to proceed and you have the right to fit this in your schedule.

Having started an annual, you face a dilemma, as an IA because you are expected to make entries in the maintenance records concerning any discrepancies (Others here may argue otherwise and I would leave that up to you to decide). If you can correct them, it’s simple. But if correction involves more than rigging or changing hardware and you don’t have the time or an owner lacks resources; how do you handle a situation like this? This is one of the downsides of dealing with 70 plus year old airplanes that have changed hands through the ages.

I recommend you do the best you can to help this pilot, but remember you were not the one that bought an airplane and apparently proceeded to fly it without performing the due diligence necessary to make sure it was airworthy.

Aircraft With Discrepancies or Unairworthy Conditions

If the aircraft is not approved for return to service after a required
inspection, use the procedures specified in 14 CFR part 43,
§ 43.11. This will permit an owner to assume responsibility for
having the discrepancies corrected prior to operating the aircraft.
Discrepancies or unairworthy conditions can be resolved in the
following ways:
1. The discrepancies can be cleared by a person who is
authorized by 14 CFR part 43 to do the work. Preventive
maintenance items could be cleared by a pilot who owns or
operates the aircraft, provided the aircraft is not used under
14 CFR part 121, 129, or 135; except that approval may be
granted to allow a pilot operating a rotorcraft in a remote
area under 14 CFR part 135 to perform preventive
maintenance.
2. The owner may want the aircraft flown to another location to
have repairs completed, in which case the owner should be
advised that the issuance of FAA Form 8130-7, Special
Flight Permit, is required. This form is commonly called a
ferry permit and is detailed in 14 CFR part 21, § 21.197. The
certificate may be obtained in person or by fax at the local
FSDO or from a Designated Airworthiness Representative.
3. If the aircraft is found to be in an unairworthy condition, an
entry will be made in the maintenance records that the
inspection was completed and a list of unairworthy items
was provided to the owner. When all unairworthy items are
corrected by a person authorized to perform maintenance
and that person makes an entry in the maintenance record
18
for the correction of those items, the aircraft is approved for
return to service. (Refer to appendix 1, figures 8 and 9.)
Incomplete Inspection

If an annual inspection is not completed, the holder of an IA
should:
1. Indicate any discrepancies found in the aircraft records.
2. Not indicate that an annual inspection was completed.
3. Indicate in the aircraft records the extent to which the
inspection was completed and all work accomplished.

The above taken from pgs 18/19 of FAA-G-8082-19 “FAA Inspection Authorization Information Guide” WHAT LOG ENTRY SHALL BE MADE..?? ?
FAR43.11(5) applies: “ “I certify that this aircraft has been inspected in accordance with (insert type) inspection and a list of discrepancies and unairworthy items dated (date) has been provided for the aircraft owner or operator.”

This means the Actual Discrepancies are not listed in the logs……but are given directly to the owner….. UNLESS…the Annual Inspection is NOT completed. If the Annual is NOT completed…then an entry LISTING THE DISCREPANCIES FOUND shall be made in the aircraft logs (mx records)…and NO comment be made that an “annual Inspection” was performed.

No matter how you cut it, if an IA performs an annual inspection per Part 43 (completed or not), a maintenance record is required. If discrepancies are noted, that fact is recorded in some manner and becomes part of the airplane’s maintenance history. The guidance allows some leeway as to how this is accomplished. I have seen some shops detail similar issues on a work order, presented to the owner, and leaving the airplane logbooks blank. I know some who would be content and legal in recording it on a piece of scrap paper (hopefully including aircraft ID, time in service, date, and mechanic certificate #). This is perfectly legal and then becomes the owner’s responsibility as to what to do about it. But it must be documented.

In the situation under discussion, this IA is seeking technical advice on an STC that lacks documentation and appears to have involved a faulty installation. I am suggesting that this requires seeking certainty concerning its current status. Perhaps not an easy undertaking. If this cannot be accomplished, the airplane cannot be returned to service and is deemed un airworthy by an authority (the IA) who is authorized to make that decision. The owner must be notified in writing.

This is a timely topic for owners and technicians involved with older aircraft. It is germane to the recommendation that a pre buy require an annual inspection. What if this buyer had a pre purchase annual and discovered a serious discrepancy. The airplane is now effectively grounded and the seller is forced to deal with the consequences. Maybe that’s a good thing. It is certainly worth considering when buying or selling any aircraft.

I have been relieved to find such amiable forum members. These posts are exactly my thinking and how this should be handled. I appreciate the feedback. It is a testament to those who are determined to keep great aircraft flying and legal.

I'll post more as I proceed on this endevour to correct a serious problem.

Thanks to all.