New 170B owner and Pilot - Avionics questions..

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GAHorn
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Re: New 170B owner and Pilot - Avionics questions..

Post by GAHorn »

It's probably not just an "Alaska" thing....
Going from one uncontrolled field to another uncontrolled field in low weather, regardless of locale, ...especially for short distances over known territory... it's fairly common to avoid the troubles for an IFR clearance... especially as neither field likely has a departure or arrival procedure. What's ATC likely to do for you in such a case?

But either way, those gyros are important equipment, IMO. An inadvertent entry into the clouds makes them paramount for survival in such cases, regardless of clearance/legalities. (I'd sooner fly with a tach, oil temp or oil press gauge inop in such circumstances.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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GAHorn
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Re: New 170B owner and Pilot - Avionics questions..

Post by GAHorn »

n2582d wrote:
gahorn wrote:... Yes...because the regulations also require that they be operable if-installed.
The way I read FAR 91.213 you are completely legal with the instruments placarded inop. provided that there is an entry in the maintenance log to go along with that action. The FAR starts with "Except as provided in paragraph (d) of this section" ... . Here's paragraph (d):
(d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided—
...
(3) The inoperative instruments and equipment are—
...
(ii) Deactivated and placarded “Inoperative.” If deactivation of the inoperative instrument or equipment involves maintenance, it must be accomplished and recorded in accordance with part 43 of this chapter;
In other words, forget all the mumbo-jumbo about MELs. You can placard the instrument "inop" if it's not required for the type of flying you're doing. That being said, I still agree with George's conclusion:
You should either repair/replace or remove them.
I agree with Bill's idea's on troubleshooting;
3958v wrote:You might check a few other things. First is there a filter on the gyros. If so replacing them might help. If your instruments have no filters you might check to see if the inlet screens are plugged with lint. Another possibility would be old vacuum hoses that are cracked. Bill K
You could be showing adequate suction but if the filters or screens are clogged you won't be getting adequate flow to turn the gyros. If both instruments went belly up at the same time I'd also be checking the suction relief valve as seen in Fig. 77 of the IPC:
Suction Relief Valve.jpg
Not trying to start any controversy over this, but.... That strict reading of the FAR leaves a lot to be "assumed", IMO. For example, it makes no mention of a need of determination by an appropriately-rated person for the reason those instruments are inoperative. For example, what if the reason they are inoperative is because a vacuum pump stripped a gear and dropped parts down into the crankcase? If the pilot simply says to himself, "oh..lookee here... no problem, I'll just placard them "inop" and get on down the road..." Then the stripped gear causes an engine failure on takeoff. Whoops.
My point is that just because a piece of installed equipment is inoperative... that condition alone may not be sufficient reason to judge a flight with it inoperative..to still be safe... unless other considerations are made.

In this case, a new owner has accepted an airplane that has just undergone an "annual/prebuy" inspection that has returned to service with inoperative equipment. Hopefully that inspector made some sort of determination that the two air-driven gyros are failed because of a reason which does not make the aircraft otherwise questionable to fly other than to simply put an "inop" sticker on the inst. face. (likely the case in a venturi-driven vacuum system but nonetheless an important if minor point. I'm just for the sake of discussion, offering an example of how what might appear to be a simple matter might actually be otherwise.)

The AOPA article introduces a similarly misleading assumption. It leads one to believe that a pilot, landing at an off-route airport for a hamburger...then returning to the aircraft and on taxy-out discovering an inop gyro ... could simply placard it "inop" and fly home in VFR conditions. That implies that no other serious reason could exist for a non-essential equipment failure.... which is simply wrong.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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lowNslow
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Re: New 170B owner and Pilot - Avionics questions..

Post by lowNslow »

I disagree George. The AOPA article is not making any assumptions in regard to your scenario, the FARs already address what is acceptable. The AOPA article addresses how long you can delay resolving the malfunction. Here is the applicable FAR:

FAR 405(c)requires that equipment permitted to be inoperative under § 91.213(d)(2) must be “repaired, replaced, removed, or inspected at the next required inspection.”

According to this it perfectly legal to continue the flight. Now whether or not it is wise to continue is another question and that is when those pilot in command decisions come into play.
Karl
'53 170B N3158B SN:25400
ASW-20BL
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GAHorn
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Re: New 170B owner and Pilot - Avionics questions..

Post by GAHorn »

The point I'm thinking of is related to those words " or inspected at the next required inspection.

In the scenario mentioned above, after the hamburger is paid for and the failure is discovered on taxi-out.... might not be anywhere near "the next required inspection." Something more serious than a failed gyro might be causing that gyro to appear failed.

I'm dotting the "I" and crossing the "T" , I realize... but the AOPA article seems to imply the pilot can continue the taxi-out and go fly off into the blue... when in fact, the actual cause of the perceived failure should be determined by someone appropriately rated to do so... IMO. I don't feel that a new owner who has no pilot certificate (as of yet) should be advised they can continue to fly with inoperative equipment unless that determination has been made by an "appropriately rated person" who has actually seen the equipment.

Perhaps that was accomplished during that recent annual/prebuy... but that's neither exactly-clear in this thread, nor does the AOPA article clarify it. ( Again, IMO. I appreciate the discussion/response, and I ordinarily would consider an "appropriately rated person" to include an appropriately-rated PIC .... I just feel that more consideration should be given to operating with INOP equipment.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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ghostflyer
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Re: New 170B owner and Pilot - Avionics questions..

Post by ghostflyer »

I am astounded that the issue over inop instruments center around the legalities and who said what and how or the cost . The bottom line is mr Cessna put them there for a reason ,plus you need everything in the world to help you when it,s time for a really bad day . No one can forecast when you are going to have a bad day . Plus all our ability as a pilot is different ,
From the guy in the next hangar. MEL,s or CDL,s are designed for aircraft with multiple same systems and not to be used as a excuse for our type of aircraft unservicabilities .
Some of the instruments fitted to our are over 60 years old and are worn out. We can overhaul them and fit new bearings etc , but the tolerances internally have been compromised but still pass for the time being . How many times we read that “I have had the gyro such such overhauled 12 months ago and it s now broken again .
Plus one of our very learnered member told me he is using 30 year old radios. These radios had their internals components are soldered together and soldering joints break down over the years through vibration and chemical reaction. I had a very eye opening experience in a radio shop where a very old but serviceable radio [bendix [???] ] was compared with a new out of the box ICOM 210 radio. The clarity and range of the ICOM 210 was unbelievable and the new cost was reasonable . The power output was susposed to be similar but the Bendix was pumping about 4.8 watts [specs say 7.5 watts] and the ICOM was 7 watts [specs say 7.5 watts].
So what I am saying , the old world charm is good, but safety is better.
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GAHorn
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Re: New 170B owner and Pilot - Avionics questions..

Post by GAHorn »

Hey, Richard!.. Ya' better get rid of that 60-year-old airframe and get an Airbus! :lol: :lol: :lol: :lol:

I feel the cart is getting before the horse in this discussion. (and since I'm the one that first hinted at the regulatory side of things, I feel I should reply. I hope this doesn't "smack" of me trying to "own" this discussion... that is certainly not the case.)

The reason for the student-pilot's question is surely that the gyro horizon and compass are not required equipment for the airplane to legally fly if they're not installed at all.... so why not fly with them simply INOP?

The reason for the regulatory guidance (which being presumed to guide this discussion) is to provide supportive guidance to all who are faced with a situation that may involve safety of operation.
Every such regulation has that as its basis of existence. A more stark example of regulatory guidance might be if you've landed where avgas is not available. Would it be OK to use mogas instead?
Regulation says "Yes" if the aircraft has a mogas-STC but "No" if it lacks that STC. I'd be willing to guess that most of us wouldn't think twice about putting sufficient mogas in the airplane to get to the next re-fueling stop where we can buy avgas.... Regardless of the STC approval for the airplane applies to THIS airframe or not. Let's say, this airframe does not have that mogas STC... but we
know other 170s operates safely with mogas...so we put in mogas and taxi-out for the short hop to the next airport with avgas.

(let that soak-in for a moment)

(OK..now it's soaked in)

The next takeoff results in the engine blowing-up at 300 feet over the lake. 8O

The coroner and the news outlets ....and the accident investigators are amazed the dead pilot put automotive gas in the airplane.

Surely everyone knows that the IO-360 engine that 170 had installed required 100 octane avgas!

OK... so that's a made-up example of how regulations support safe operations.... without insuring safe operations. And that's why this thread involves the regulatory-guidance in its discussion. The regs don't make the flight safe. They only support that and should be included in the discussion. IMO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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IA DPE
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Re: New 170B owner and Pilot - Avionics questions..

Post by IA DPE »

gahorn wrote:Hey, Richard!.. Ya' better get rid of that 60-year-old airframe and get an Airbus! :lol: :lol: :lol: :lol:
It is because of the Airbus that I can afford the 60 yr. old airplane :D

For a multitude of reasons, if I were the Topic Starter, I'd get the gyros fixed. But I'm not him- just a lowly bus driver. :D We each have to make our own decisions.

He's going to have to use his 170 with repaired gyros or rent an airplane with operative gyro instruments for his training to comply with FAR 61.109(a)(3), and again to complete AO VIII on the check ride. I suspect that renting one would cost close to half what the gyro repairs would cost, so one could look at it either way. I used my C-120 and a borrowed A36 Bonanza on my Commercial checkride. The Examiner didn't charge extra, but now having the shoe on the other foot I'd understand if he would have due to extra hassle and extra time.
1955 C170B N2993D s/n 26936
1986 DG-400 N9966C
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