Cowling Fasteners missing C172

chickencanfly

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Chickencanfly
Recently I had a checkride and DPE noticed that one of the Cowling Fasteners is missing Cessna172 (I did not notice it in the preflight). Asked him for time to investigate if safe to fly with one fastener missing; so I called a mechanic and he did not know the official answer. So I asked for a discontinuance.

Did I do the right thing, asking for a discontinuance?

If I answered, yes it is safe to fly and it is not, then he would have failed me, right?

I cannot find the proper answer to how many Cowling Fasteners can be missing and still be safe and airworthy to fly. Where can I find an answer from an official source?
 
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If they are Southco's I'd say none. Those things are barely doing the job as is.
 
I cannot find the proper answer to how many Cowling Fasteners can be missing and still be safe and airworthy to fly.
The infamous check ride missing screw question. If I had a nickel for every...:)

No fasteners can be missing from an airworthy standpoint. So canceling the checkride probably indicated to the DPE you possessed proper regulatory decision making skills. ;)

FYI: there are some larger aircraft that have MEL relief to fly with "some" missing fasteners for a limited time, but as stated above I haven't seen such relief for a 172.
 
No fasteners can be missing from an airworthy standpoint. So canceling the checkride probably indicated to the DPE you possessed proper regulatory decision making skills. ;)

Discontinuing was the right call. I'd bill the FBO for the retest fee.
 
No fasteners can be missing from an airworthy standpoint.
There’s a lot of un-airworthy Cessna training aircraft out there than. I’d bet a good fraction of the 172’s sitting on flight lines across the country have missing fasteners.

Since it was during a check ride, the right decision was made, but in reality, it really doesn’t matter much. One or two missing? Not going to make a difference.
 
Accidents are usually a sequence of events with any one item in the value chain could have halted the events stopping an errant outcome.

2 or 3 ineffective or missing cowl fasteners might be OK, until an unusual attitude causes pressures on the cowling to flex and pop another fastener. Vibration could now cause cowling to fail in flight, creating a bad day in the air.

It's up to the PIC to make sure the ship is in good order and determine if any squawks would potentially impair safety. We all probably know someone on our field no one will fly with due to the ramshackle maintenance practices. That would have no problem flying with 2-3-4 missing or flakey cowl fasteners.
 
You guys would whine like a rupture duck, If I downed your 172 for a missing fastener.
The OP did not ask what I thought was reasonable or prudent. They asked what the “right” answer was to number of fasteners allowed to be missing and whether or not it was appropriate to stop the check ride.

On a side note if you released an aircraft to me after an inspection signed off/airworthy and there were cowl fasteners missing it would be the last time you worked on my equipment.
 
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I’d bet a good fraction of the 172’s sitting on flight lines across the country have missing fasteners.
Last 150 I rented had at least a dozen missing from various places (one here, one there). Cracks in many fairings. You could wiggle the front of the cowl up and down nearly an inch. Rear tie down was rattling around loose. Structural Bondo blobbed on the wing tip. Generally loosey goosey. Don't remember what else, it's been a few years. But, it didn't seem likely to me that it would fall out of the sky in the next few hours (and I was right :) ).
 
To answer the question, it's never a wrong answer to not fly if you have doubts about the airworthiness of the aircraft (or the weather, or your personal suitability for flight).

The word is "discontinuance" by the way.
 
Is it just me or does the OP look like he has the cowl fastener, and he's missing the 172
 
You guys would whine like a rupture duck, If I downed your 172 for a missing fastener.
How does that exactly work--your "downing" an aircraft?
 
but in reality, it really doesn’t matter much. One or two missing? Not going to make a difference.
It depends... Said the guy whose cowling remnants I collected from a field one day...:rolleyes:
 
It depends... Said the guy whose cowling remnants I collected from a field one day...:rolleyes:
There was more than just one or two missing fasteners if that happened.
 
There was more than just one or two missing fasteners if that happened.
No. There were exactly 2 missing. We found them in his jacket pocket. They just happened to both be in the wrong place at the same time. Remember, not all aircraft are created equal grasshopper.;)
 
You guys would whine like a rupture duck, If I downed your 172 for a missing fastener.
That's why you keep a bag of the most common fasteners in the glove box.
 
That's why you keep a bag of the most common fasteners in the glove box.

Unfortunately for the OP, he couldn't install one, it needs an A&P. You might stretch the notion of maintenance removing the cowling and say that a pilot can do it, that's between you, your A&P and the FAA. But if you recall, the OP was at their checkride, so either way...it was a no go.
 
Unfortunately for the OP, he couldn't install one, it needs an A&P.
Why? Provided the OP had a PPL and wasn't a student, I can think of 2 prevent-mx items the fastener install could fall under plus the remove the cowling you mentioned. But agree it wouldn't have been prudent to fix or install the fastener with the DPE standing there.
 
You don't install fasteners, you fasten fasteners--no A&P required. Now if the cowl mount that the fastener fastens into needs to be replaced, that's different.
 
Why? Provided the OP had a PPL and wasn't a student,...

I guess I didn't read it directly, but I thought the OP was taking a private check ride. Am I wrong?
 
I guess I didn't read it directly, but I thought the OP was taking a private check ride. Am I wrong?
No idea. OP only said checkride hence the qualifier in my post.
 
Do you realize that many Coulings are simply screws?
the Cessna 172 / 150 cowling can have 2 other type of fastener
Product
SKYBOLT CESSNA COWLING FASTENER CONVERSION KITS

Huh? You do realize that the OP was missing the fastener and not the whole friggin' mounting assembly? Regardless of whether you're missing a screw, a southco, a dzus or whatever, you don't need an A&P to replace a missing fastener of the same type that rattled loose. If you want to convert the existing mounting system to some other mounting system, then you do need a A&P to know how to make it legal.
 
So they can rattle out and get caught in the seat track.

Another reason to fly nude so that nothing can fall out of your pockets and get caught in the seat track.
 
Regardless of whether you're missing a screw, a southco, a dzus or whatever, you don't need an A&P to replace a missing fastener of the same type that rattled loose.
Show us how to replace a deus button.
Do you have the tool? It takes a whole kit for all the sizes

https://www.aircraftspruce.com/search/search.php?s=dzus

Dzus is only one type of fastener, several require special tools.
search.php
tell us what "complex assembly "means when talking with a FAA inspector.
 
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(1) Part 43, appendix A, paragraph (c) contains the Federal Aviation Administration’s (FAA) list of tasks that meet the requirements of the preventive maintenance definition. If a task or maintenance function does not appear in the list, it is not preventive maintenance. Also, because of differences in aircraft, a function may be preventive maintenance on one aircraft and not on another. To provide for this, paragraph (c) contains the limitation, “provided it does not involve complex assembly operations” on the aircraft involved. Owners and pilots must use good judgment when determining if a specific function should be classified as preventive maintenance.
 
I guess for some people "complex assembly operations" include using a screwdriver and making a quarter turn.

Screwing a cowling on is not a complex operation and allowed for a a private pilot to perform. The OP was still a student pilot on a check ride monitored by his DPE.

A PPL holder can loosen or tighten the cowl fasteners, but installing a new cowl fastener needs an airframe log entry by an A&P.
 
but installing a new cowl fastener needs an airframe log entry by an A&P.
Why? As I mentioned above there are a couple prevent-mx line items that should cover those fasteners.
 
A PPL holder can loosen or tighten the cowl fasteners, but installing a new cowl fastener needs an airframe log entry by an A&P.
So reading that says a simple screw is required by A&P

Don't think so.
But when the cowl fastener must be assembled, the whole operation is repair requiring an A&P

Remember the brake puck example? the riveting of the puck is a complex assembly.
 
Why? As I mentioned above there are a couple prevent-mx line items that should cover those fasteners.
depends upon what type fastener. The FAA has said that when special tools are required it is a complex assembly.
when the fastener is a type requiring riveting it is certainly is.
 
So reading that says a simple screw is required by A&P

Don't think so.
But when the cowl fastener must be assembled, the whole operation is repair requiring an A&P

Remember the brake puck example? the riveting of the puck is a complex assembly.
I agree with you, my language could have been more clear. I was referring to the operation of turning the cowl fastener screw to remove/replace the cowl for preventative maintenance like an oil change; as opposed to replacing the screw captured by the fastener unit.

If someone is mechanically inclined, some of this work is pretty easy and straight forward. Easy enough to do under A&P supervision during annual inspection time or while some other maintenance is being performed needing an A&P log entry.
 
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depends upon what type fastener. The FAA has said that when special tools are required it is a complex assembly.
True. But in the context of replacing a fastener or the simple repair of the a fastener receptacle for a 172 cowling, it's been my experience these type items, among others, easily fall under preventive mx per 43 Appx A(c)(12) & (26). But, as with any regulation, it is subjective to that persons interpretation and inherent skill set whether they will be comfortable performing that type of preventative mx.
 
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