annual inspection - questions

[200hr Wonder]

One thing I can also suggest is always ask for replaced parts back. Something I always do with a car or truck. For example if you go in for break work and the shop tells you that you need new rotors, ask for the old ones back. If they look f*cked then cool, if you are not sure take em in to a parts shop for a measuring. Same goes for a plane, at least the first few times. Ask for any worn out parts to be returned, just to keep em honest. Can't hurt right?

[qa guy]

Here's how it works at our shop, and frankly, I believe this is how it should be everywhere.
The first time an airplane goes through the shop, the customer is billed 2 hrs. for a detailed log book evaluation. This determines which ad's, sb's, and whatever other publications are deemed as necessary by the manufacturers, or the governing authourity. It will be the best $150 the owner ever spent! After this we look after everthing!
Then, a PROPER annual is carried out. This includes all items included in CAR 625 "Out of Phase tasks" (By the way if you're going to bill the customer for it , better do it)! Otherwise, tell him the compass swing is a "big waste of time" and save him the hour of labour. Dont bill him for
!@#$ you didn't do!
Once the inspection is complete, and all the snags are recorded, the customer is briefed on his quote. This could be in person, by telephone, or these day's usually by e-mail. At this point he chooses what he wishes to repair, and what mandatory requirements he would like to comply with.(Hopefully all.)
Whatever the owner chooses to defer is his responsibility. It is in our best interest to record if necessary that "This defect was deferred by the owner", and thats exactly how we phrase it on the work package.
Finally, carry out the work that was authourised by the owner, "according to the applicable standard of airworthiness" and everybody's happy!
Then again, I know it's rarely this easy!

[MCRS]

Yes, sometimes you run into the planes that have had major modifications carried out by some one that should not have.
Like a non certified Wipline door on a 206 with no STC or any supporting documents other then this piece taken from wreck so and so this piece taken from another wreck different model so and so and so on and so on. At that point I am sorry, but you will look far and wide for an AMO (That is above board! )/ AME (That is above board! ) to sign off on that.
It does happen, I have seen it! That is a bit extreme but you get the picture! Just remember the AMO/AME doesn't have to sign off the log book if he deems the non compliance with certain AD's, SB's or conformance are not upto par. This however, appears not to be an issue with you from the way you have been looking at things you shouldn't have a problem.
Especially if you follow the great advice from the posters above.

[Strega]

Yes, sometimes you run into the planes that have had major modifications carried out by some one that should not have.
Like a non certified Wipline door on a 206 with no STC or any supporting documents other then this piece taken from wreck so and so this piece taken from another wreck different model so and so and so on and so on. At that point I am sorry, but you will look far and wide for an AMO (That is above board! )/ AME (That is above board! ) to sign off on that.
It does happen, I have seen it! That is a bit extreme but you get the picture! Just remember the AMO/AME doesn't have to sign off the log book if he deems the non compliance with certain AD's, SB's or conformance are not upto par. This however, appears not to be an issue with you from the way you have been looking at things you shouldn't have a problem.
Especially if you follow the great advice from the posters above.

Yes and no, if an AME does an annual, to the applicable standards, but there are still some ADs left outstanding, then he still needs to sign off the annual.


Also IIRC the 500 hr inspection on the Mag inpulse coupling is a SB, NOT an AD, Compliance is not reqd for a private operator.

[Hedley]

500 hr impluse coupling mag AD:

http://www.tc.gc.ca/aviation/applicatio ... -12-06.htm

[Strega]

500 hr impluse coupling mag AD:

http://www.tc.gc.ca/aviation/applicatio ... -12-06.htm

Ok my bad,


But what if you have slick magnetos?

[MCRS]

Strega
Yes, sometimes can be a gray area here. I have had some DOMs say if anything fails the Annual inspection ie find a bald tire, and owner doesn't want to change it, then you don't sign off the Annual.(Bit of a lame example but you get the idea!)
Then I have worked for other DOM's who say you sign off the Annual if you have carried out everything listed in the Annual
again example. Inspected the tires check (regardless if they are bald or not!) then put down the finding on a defect sheet like the tire was Bald! then once everything is done and the owner is consulted and decides he wants to run on said bald tire, the entry would state like what QA posted. Annual completed, Owner defered Bald tire........
This is a whole new list of defects that could infact keep the Aircraft grounded, without the AME/AMO signature, This was more or less what I was refering to in my post. If it still isn't making sense could be the hour I am typing this 22 hours no sleep right now! Good thing I am not working on a Airplane at present!
Time to hit the hay!

[SeptRepair]

I hear what your saying mcds, i have been away from dealing with Cars and private operators for about 7 years but i remember the point of defects, which are hidden from the owner/operator, must be recorded as being hidden in the log book. The example being tires. If a tire is bald down to the cords and no wheel pant installed then technically it isnt a HIDDEN defect, therefor no statement in the log book needs to be made. However if that same tire was hidden by a wheel pant, then by law it must be recorded as a hidden defect. We all must remember the final statement we make when signing out. The maintenance described herein has been performed in accordance with the applicable standards of airworthiness.

[SeptRepair]

One thing I can also suggest is always ask for replaced parts back. Something I always do with a car or truck. For example if you go in for break work and the shop tells you that you need new rotors, ask for the old ones back. If they look f*cked then cool, if you are not sure take em in to a parts shop for a measuring. Same goes for a plane, at least the first few times. Ask for any worn out parts to be returned, just to keep em honest. Can't hurt right?

Well i would like to think most maintenance operations are legit. Other than obvious warpage of the disc or the disc measuring below min limits its pretty hard to justify changing the disc if its just rusty or has some small pits. There are not to many parts shops out there who are going to interfere and measure your discs for you to see if they needed changing. They are in the business to sell parts and are not trained to determine what is or isnt servicable.

[Hedley]

a bald tire

Hold on a sec here ... this is a bit of a tangent, but I want
to point out that a bald tire is NOT by definition unserviceable.

The tire tread on a buck fifty, say, provides little to no utility,
nor is a bald tire on a buck fifty unsafe.

For example, on our Pitts, which I will often touch down at
120 mph (wheel landing) I run six ply Goodyear Flight Custom
III tires, which are the best tires I can find. Don't care what
they cost. I used to run them bald, and then panic when I
saw cord, and change them.

But just for grins, when I changed the tire, I cut the cross
section of the tread where the cord was showing, and was
shocked to see how much tread was still remaining - lots
and lots!

Many people try to save the 8 ounces a side (!) and run
4-ply tires on their Pitts. Ok, says I, if that's serviceable,
then I can go through 2 layers of cord before I have to
change the tire. And that's exactly what I do - and when
I cut the cross-section of the worn tire, I surely do have
4 plies left. Looks like crap, though.

I did a little research on the subject, and it turns out
that on the CF-104, which lands faster than any aircraft
anybody here has ever worked on, they used tires with
many, many plies and thus did not panic when you saw
a bald tire, and even cord. I am told that many -104's
sitting on the ramp had yards of string hanging out all over,
and they were still serviceable. Go figure.

Sorry for the thread-jack, but the question, "Is a part
still serviceable?" is not always easy to answer correctly,
and god knows different AME's have different opinions - you
might as well ask ten economists what they think the
economy is going to do in the next year.

FWIW I am more concerned about an elderly,
weather-checked tire which has seen little use
but lots of UV, than I am by a much newer, bald
tire which has seen more landings.

[qa guy]

Some of us have a misconception that when we sign off on a private annual, we are claiming that the aircraft is safe to fly...or there are no outstanding defects....not the case gentlemen.
Back in the day(and this is before my time in the av biz) we signed off annuals as "This aircraft is fit and safe for flight......." or something along those lines. However, today we do not carry that burden. We do not have to be pressured to claim something is safe, when we know it's not.
I'll use the tire example. The tire was inspected and worn to the cords. It was addressed as a defect. Now the owner decides if he wants to replaced it, or chance it. Again, in signing the annual off we are just claiming to have inspected it. If something is deferred that I feel is an airworthiness issue, I would even have the owner sign that task right where it say's "This defect deferred at owners request" just to make sure there are no misunderstandings.
Kinda funny how that works though. Take your car in for a certification and you cant defer anything the mechanic feels is unsafe. However, it's better for us AME's this way!

[SeptRepair]

Hedley i have to disagree with you on operating on bald tires. When i was a younger engineer i used your reasoning on running a bald tire. Except i called the limit as soon as cords showed. A much wiser and older engineer caught me using this logic and made me think. "You work on the west coast and it rains here a hell of alot. Cars hydroplane on bald tires, do you not think airplanes suffer from the same condition if they are bald on a wet runway? If they didnt needs treads then why the hell do they put them on?" I kind of felt stupid because his logic was a hell of alot more sound than mine. I had no logic except i was trying to save the operator money by stretching his tire wear as long as possible. Here is a finding by NTSB;

NATIONAL TRANSPORTATION SAFETY BOARD
Office of Research and Engineering
Washington, D.C. 20594
May 26, 2006

When hydroplaning occurs, the tires of the aircraft are
completely separated from the actual runway surface by a
thin water film and they will continue to hydroplane until a
reduction in speed permits the tire to regain contact with the
runway. This speed will be considerably below the speed at
which hydroplaning commences. Under these conditions, the
tire traction drops to almost negligible values and in some
cases the wheel will stop rotating entirely. The tires will
provide no braking capability and will not contribute to the
directional control of the aircraft. The resultant increase in
stopping distance is impossible to predict accurately, but it has
been estimated to increase as much as 700 percent. Further, it
is known that a 10-kt. crosswind will drift an aircraft off the
side of a 200-ft wide runway in approximately 7 sec under
hydroplaning conditions.

The minimum speed, in knots, at which
hydroplaning will commence can be calculated by multiplying
the square root of the tire pressure (PSI) by 7.7 for a nonrotating
tire, or by 9 for a rotating tire.
This equation gives an approximation of the minimum speed
necessary to hydroplane on a smooth, wet surface with tires
that are bald or have no tread. For example, the minimum
hydroplaning speeds for an aircraft with tires inflated to
49 PSI are calculated as:
NON-ROTATING TIRE: 7.7 X v49 = 54 KT.; or
ROTATING TIRE: 9 X v49 = 63 KT.

[Hedley]

hydroplaning

Good point, but remember that when light trainers
first touch down, due to the considerable lift still
being generated I am doubtful as to the requirement
for perfect traction at higher speeds.

All of us have changed tires that some blockhead
pilot has flat-spotted by getting on the brakes too
early in the landing roll, before the weight of the
aircraft is on the tires.

When the aircraft slows down, and some weight
goes on the tires as lift decreases (it's a function
of the square of velocity) then the tires can provide
some braking action if required. By that point, you're
almost certainly under your calculated hydroplaning
speed anyways.

Again, I remain unconvinced of the requirement for
tread on light aircraft tires. If there was any need for it,
we would have something considerably more sophisticated
than the "double cut" tread in the tires, which mostly serve
as tread wear indicators.

I personally operate all sorts of less-than-12,500 lb
aircraft (single, twins) from many varieties of surfaces
(ice, grass, gravel, pavement, water-covered, etc) and
I really don't think it's fair to blame a lack of traction for
many accidents involving these kinds of aircraft. Keeping
the approach speed down (kinetic energy is a function of
the square of velocity) and staying on the glidepath can
help, too.

Pilots that come in high and hot in light aircraft then lock
up the brakes to try to get stopped before the end of a
5,000 foot runway have bigger problems than tire tread
pattern.

[Strega]

Hedley i have to disagree with you on operating on bald tires. When i was a younger engineer i used your reasoning on running a bald tire. Except i called the limit as soon as cords showed. A much wiser and older engineer caught me using this logic and made me think. "You work on the west coast and it rains here a hell of alot. Cars hydroplane on bald tires, do you not think airplanes suffer from the same condition if they are bald on a wet runway? If they didnt needs treads then why the hell do they put them on?" I kind of felt stupid because his logic was a hell of alot more sound than mine. I had no logic except i was trying to save the operator money by stretching his tire wear as long as possible. Here is a finding by NTSB;

NATIONAL TRANSPORTATION SAFETY BOARD
Office of Research and Engineering
Washington, D.C. 20594
May 26, 2006

When hydroplaning occurs, the tires of the aircraft are
completely separated from the actual runway surface by a
thin water film and they will continue to hydroplane until a
reduction in speed permits the tire to regain contact with the
runway. This speed will be considerably below the speed at
which hydroplaning commences. Under these conditions, the
tire traction drops to almost negligible values and in some
cases the wheel will stop rotating entirely. The tires will
provide no braking capability and will not contribute to the
directional control of the aircraft. The resultant increase in
stopping distance is impossible to predict accurately, but it has
been estimated to increase as much as 700 percent. Further, it
is known that a 10-kt. crosswind will drift an aircraft off the
side of a 200-ft wide runway in approximately 7 sec under
hydroplaning conditions.

The minimum speed, in knots, at which
hydroplaning will commence can be calculated by multiplying
the square root of the tire pressure (PSI) by 7.7 for a nonrotating
tire, or by 9 for a rotating tire.This equation gives an approximation of the minimum speed
necessary to hydroplane on a smooth, wet surface with tires
that are bald or have no tread. For example, the minimum
hydroplaning speeds for an aircraft with tires inflated to
49 PSI are calculated as:
NON-ROTATING TIRE: 7.7 X v49 = 54 KT.; or
ROTATING TIRE: 9 X v49 = 63 KT.

Could you derive this from first principles for me?

[twotter]

[quote]Quote:
how do you estimate "500 Wheel Miles"?


Heh. Shot in the dark: each takeoff and landing cycle
at a small airport is probably one mile. At a large
airport, with a lot of taxiing, it might be two miles. You
know how many takeoff and landings you do, so you
do the arithmetic.
[quote]

Another reason to do your wheel bearings might be if you have not used the airplane much it may have collected water in the bearings. This will cause corrosion which will not only eat the bearings but the races as well.. I would err on the side of caution here.. At least every 200 hrs or 2 years.. IMHO..

[office_supply]

Do you guys know where I can find a service manual for an O-235-C2C ? Lycoming's website seems to have nothing useful, nor does eBay. All I have is an overhaul manual which to me is rather useless. Trying to find specifics for oil filter cleaning and plug maintenance. I plan on doing on oil change over the weekend.

Thanks,
office_supply

[Hedley]

While having the manuals around it great,
I think you really need someone who knows
what they are doing, to show you how to
do the above.

Some tips:

1) you don't clean a normal oil filter, you
replace it. You're supposed to cut it open
to look for metal but hardly anyone does.
Torque it and lock wire the new one.

2) you clean oil pressure screens on older
engines that don't have oil filters. Again,
lock wire will likely be required.

3) don't drop spark plugs. If you do, the
porcelain may be cracked - throw it out.
Get a spark plug tray. Learn how to clean
and gap spark plugs, probably to 17 to 21
thou. Torque them to 30 ft-lbs. Replace
them when they are worn.

I really, really think you need someone
to show you how to do this, the first
time. There is no legal requirement for
this, but it is wise nonetheless. Your
mentor need not be a licenced AME.

[SeptRepair]

Could you derive this from first principles for me?

HUH? You kind of lost me with that question.

[SeptRepair]

Do you guys know where I can find a service manual for an O-235-C2C ? Lycoming's website seems to have nothing useful, nor does eBay. All I have is an overhaul manual which to me is rather useless. Trying to find specifics for oil filter cleaning and plug maintenance. I plan on doing on oil change over the weekend.

Thanks,
office_supply

Like Hedley said, clean the screens replace the filters. I always check the filters, its nice to know if there is any potential problem you should be aware of. Screens just catch part numbers, filters will catch slivers. Filters are a breeze to change, make sure ya dab a little oil on the gasket before installing and tighten it as per the torque instruction on the filter , if lazy and no torque wrench, hand tight and a 1/4 turn more with a wrench. Really no different than changing a filter on your car/truck. Just make dam sure you run up and check for leaks after you have changed it. As for draining oil, remove drain plug replace gasket and reinstall torque and lockwire. Most aircraft have a quick drain installed so all ya do is turn click and drain. No need to piss around with plugs and lockwiring. Best to have an engineer at least once show you how to do an oil change. As for plugs, no sense messing with them if you dont have a spark plug tester and know what your looking for when testing them. Same goes for cleaning them, to dig out any lead and not crack the porcelain is an acquired skill. If ya dont have a vibrator ( hold the jokes) then let your mechanic do it.

[office_supply]

Yea my mistake, I meant screens, not filter. I dont have a filter on the engine. According to the overhaul manual, the engine has both an oil suction screen and an oil pressure screen. Though I've only heard references to one screen. I'd assume the pressure one.

The oil change itself is simple and a process I've done before. I do have a quick drain which makes it darn easy. Run up and shut down, let it drain for about a half hour with the dip stick cap (for lack of a better word) open, then close it up, and five new quarts go in. Check leaks, run up, check for leaks again. Least thats how I figure is the best way to do the process.

I'd assume the plugs are relatively clean, I always run the engine at 1200rpm leaned out quite a bit for a minute or so prior to shutdown, taxi leaned out as well. But I figure I could get the 50hr plug inspection out of the way. The plugs though, are something I've never done. Nor cleaning or inspecting the oil screen.

office_supply

[Hedley]

I think Strega is making the point that he
has a university education and you do not,
which I am not sure is terribly constructive.

Could you derive this from first principles for me?

HUH? You kind of lost me with that question.

Back on topic ... yes, you can remove, clean,
gap and re-install your spark plugs. Most
people rotate them, which means that you
install them in a different place than you took
them out of. The bottom plugs on a Lyc always
seem to fill up with lead and require time-consuming
cleaning to remove it. I am partial to a piece of
41 thou lock wire which has been ground down
to a point, for this.

You can also remove, clean and re-install
your oil screens.

Again, unless you are a mechanical hotshot,
it really really really helps to have someone
who knows what they are doing, help you
the first time you do this, even if it is not
legally required on your private aircraft. This
person need not be an AME, they simply need
to know how to R&R plugs & screens, which
is not rocket science. Like plumbing, you can
pretty much learn this in an afternoon.

You do not want to make a mistake and damage
your very expensive engine, nor do you want
to do a task incorrectly and have it cause
problems in the air.

[Strega]

Could you derive this from first principles for me?

HUH? You kind of lost me with that question.

Im asking for you to show me where this silly plug-and-chug formula came from... I really cant see that it has much meaning,,

Hedley, yes I do have an eduacation,, and Im not trying to bewittle anyone, Im just wondering where it came from, as I dont really think it has much meaning.

[office_supply]

Hedley, the best person I can think of... without waiting on and paying the AME is a friend of mine who's an auto mechanic. But without a service manual of sorts.. I dont want to go poking around the engine blind. I'd still like to find one if possible.

office_supply

[Hedley]

I might suggest poking around this website:

http://www.sacskyranch.com/pubsem.htm

Here is the horse's mouth:

http://www.lycoming.textron.com/support ... L114AP.pdf

But I don't think you're going to be happy with
either a Lyc parts catalog, or overhaul manual.
These publications assume you are already
familiar with light aircraft maintenance.

[Bullet Remington]

Hedley:

While I understand your statements with respect to tire wear, there are specified wear limits. Therefore, if I'm doing the inspection I want to do it to some established parameters. If the aircraft manufacturer nor the tire manufacturer doesn't specify a wear limit, for 12.5 and under I use AC43.13-1B Chg 1. Specifically, Chapter 9,Page 9-14 there is a complete page addressing tire issues and limits. Refer to para 9-14 ( a) which states in part " Tires should be removed when tread has worn to the base of any groove at any spot, or to a minimum depth as specified by the tire or aircraft manufacturer.

As maintainers I believe it is my responsibility to quote the authority I referring to when I tell a driver or owner something is FUBAR'd.

And if i recall correctly CARs 571.06 states that "Specified data" such as the Ac 43.13-1B is an acceptable reference? Correct me if I'm wrong here!

My main priority is safety, and serviceablility, and both go hand in hand from my perspective. ( Not implying that you are advocating otherwise, here).

Given the discussion on here with reference to tire wear, the opinions seem to like sphincter muscles! Everybody has one but nobody states a reference to limits!!

As for your comment RE: CF104s, whom ever told you that it was "common practice" to let the tires wear to the point that cords were unravelling, that person is full of fertilizer!! I worked on this pigs at AETE in Cold Lake! We never allowed those to get worn down, not even a flat spot. Those little tires turn up to quite a speed on take-off and landings!! And trust me, I've been in one landing with a flat spots, the machine vibrates like something your G/F would love to have operating on a 28 volt truck battery!!

I am tempted to make a rebuttal to some of the "resident expert's" (Streegra) comments, but then I'd be down at the over educated, unimportant, insecure, I need attention, SDS driver level!! Fer Gawd's sake somebody start a post and tell him he's the greatest thing to enter the aviation business!!!

And before I get a bunch of smart arse pilot replies, I AM a Commerial pilot AND an " Engineer". The quotation marks were for Steegra. If i were a "Pinky" engineer, I sure as heck wouldn't be on here trying to impress everybody!!

Anybody remember that bridge collapse in Minnesota? Funny thing, aabout those "Pinky Engineers". They all wear these little"Pinky Rings" , supposedly made from material, or to symbolize the material from a bride that collapsed and killed a bunch of folks!! The bridge collapsed because of design flaws from a Pinky Engineer.!!! Unfortunately, all the new pinky Engineers won'thave to worry about running out of material for those really, really cute pinky rings!! Keerist, even my Military doctor had one!! My current lawyer has one too!! One of my business partners has one! He won't wear it though! I supposed they felt insecure and unloved as Pinky Engineers, so they switched to something more respected, like a lawyer!!!