Airframe Life Span?
 

Evening All,

I have a question for you regarding the airframe life span of a C172. I am in the very early stages of looking for a lighty and have found a project that interests me somewhat, it is an early 1980's C172 with timed out engine and prop and just under 11,000 hours tt. I have not yet asked the question but it seems pretty obvious that it has been used for flying training.:eek:

The engine and the prop, as I understand things, shouldn't pose too much difficulty, except to the hip pocket nerve as I fork out for a new set.

However the frame time has me thinking:
What is the max time for a Cessna frame?
Can they go on forever as long as they are inspected?
If it was used by a flying school might it have suffered from the intermittent hard landings?
Is it a worthwhile project if the purchase price is right?

An explanatory note; I have never looked at buying an aircraft before and am therefore completely green, however, as part of my due diligence, I am attempting to gather as much information as I can.

Any and all replies sincerely appreciated, along with any good advice that you may offer. If you are kind enough to share your knowledge and experience, I am most grateful.

Cheers,:ok:

ABX

It might help you to know that I am in Australia.:ok:

Thanks.

I've never heard of any C172 airframe lifed components, ABX, unlike, say, PA38 or AA5 wings. As long as the maintenance schedule is complied with, along with ADs, the aircraft can be operated until fossil fuels run out. :)
Any primary/secondary damage caused by hard landings would be found on routine maintenance.
Ultimately, be sure to have a good engineer survey it before you buy.

Thanks stevef.

Are there any avionics components that wear out or need scheduled replacement?

Avionics generally don't wear out, they become obsolete and need upgrading. You may find that some of the older electronics are dead weight that should come out immediately, to be replaced at a later time.

Thanks barit1, I hadn't thought of avionics that way, now that you bring it up I guess some of the older stuff could be dead weight.

Sorry to be late to the party........... been meaning to throw my two pence in for a while...........

Dont let the hours put you off, there is no lifed component i can think of on the 172 at the moment....

A club aircraft may have several advantages

1, Its not spent 80% of its life sitting on the ground up to its Oleos in long wet grass rotting away, it will have been flown reguraly and had a good airflow through it to prevent the above.

2, It will have been maintained reasonably, a private owner is more likely to baulk at a large prospective bill and cut corners over a school who make a living off it..... Servicability here is the name of their game.

3, Hours, well while 11,000 is a lot compared to others if the 2 above items have been carried out it should not be a problem, GET AN ENGINEER TO GIVE IT THE ONCE OVER......... he will be able to warn you of any pitfalls....... He should know what he is doing and should be aware of any expensive items that you may incur... that is then a bargaining point in the sale, so the cost of an Engineer can save you thousands........ I did a survey of late and found the engine should possibly of had a shockload inspection 600 hrs previous........ that saved the new future owner thousands and he rejected the aircraft...

Where I work and maintain a fleet, we operate 2 Cessna 152's that have between 18,000 and 19,000 hrs on them......... they are fine, have the odd rivet starting to work and a little external corrosion showing externally only that i work through...... but I have seen 4,000 aircraft of the same year riddled with corrosion internally that have sat in fields for years............ mine do about 600 hrs to 800 hrs a year.......... which may seem alot but they used to be a lot busier.........

As said get the avionics assesed at the least........... they cost the earth (after the Eng and Prop)

Oh and happy flying...ask any questions and I will endevour to help :)

ABX:
If you want to look at the C172 Type Certificate Data Sheet, go to the FAA Home page and look under Mechanics, bottom right. Select TCDS and in the subsequent search box, enter 3A12.

Confirms no airframe lifed components.
Steve.

Thanks Nut Loose your answer is much appreciated, its good to get information from those (all who have replied) who know what they are talking about.

Thanks again stevef, I've saved that link.:ok:

Cheers all,

ABX

For what its worth and it may be worth investing in......... Cessna do a book and for the life of me I can't remember it's name, I will look at work as I have one.......

It's something like the 100 series progressive maintenance inspection book

This is based on their experiences from higher houred aircraft and gives you additional points to look at on your aircraft, will dig it out at work and let you know the title, it lists on hours and locations specific points it thinks should be addressed like as a rough off the top of my head example...... inspect the engine bearer to firewall mount (the bearer part) at 10,000 then every 5,000 hours for cracks etc.........

will get you the details tomorrow, memory allowed for :)

Thanks Nut Loose, that book sounds like a valuable asset.:ok:

When replacing an engine and prop that are out of hours, should you buy a brand new set, reco set, or a secondhand set - say from an aircraft that has had an incident that did not damage the engine/prop?

Normally, you send the engine and prop away for overhaul and refit them on completion. Count on a month to turn them round. There's always the possibility of a prop being out of limits and a replacement would make a fair dent in your beer money. So, part-used is an option. Whatever you do, don't buy anything without documentation ('Serviceable' label and log book) because your maintenance organisation won't (aren't allowed) fit it.

Yeah, I got the terminology a little wrong, out of limits is what I should have said - that is one reason that this 172 is so cheap.

As the above have mentioned get an experienced LAME to survey aircraft,
Your friendly local propshop can measure the prop on the aircraft to see if its dimensionally within limits and also look at corrosion etc.
With high wing Cessnas make sure somebody has checked seat rails, lower door post cracks and internal corrosion of wings and fuselage all of these can cause large labour bills. Inspect flap skins for cracks along trailing edge. also have condition of engine baffles checked as these also can consume a lot of time on engine overhaul.
An aircraft with high usage is actually less likely to give engine OH problems as oil is changed often causing corrosive oil build ups to be flushed out.Its the very low usage engines that can bite you in the hip pocket.
So long as lower fuselage / fire wall shows no signs of buckles the training enviroment should not be too big an issue ,you can also get the LAME to check main gear elastomeric bushings for extrusion as well.
I have looked after a number of 172's with over 10000 hrs training on them and they are still sound if not a bit tatty around the edges.
One way to go is to have the aircraft sold with a fresh hundred hourly from a reputatable workshop.
Hope the above is of some help
West aussie LAME

Can anyone recommend an aircraft of approximately 172 size that would be a good entry level aeroplane, that I could buy cheaply, do a little training in and build my hours in?

Would a Citabria fit that description?

The Citabria (or most taildraggers) will teach you the most about very broad airmanship skills. Fewer and fewer pilots today are learning this, so it's an asset to have this background.

On the other hand IFR training will be more practical in a 172.

In the end - you'll want to fly several different types to have a well-rounded CV. Thus you should consider the rental route - you won't be focused on a single type.

Several people have mentioned corrosion....

That's what would turn your airframe into an expensive mistake, and my two-penn'orth is get some-one who knows what to look for to go over every inch. In my experience incipient corrosion is very hard to spot until it's got beyond redemption, unless you're used to it.

It's age not hours, and the less use the more likely the corrosion will be, unless it's been kept somewhere like Arizona.

This seems to be true old, not bold, I have looked at a few since last post on this thread and the ones that have been sitting around for some time seem to have corrosion issues.

Two words should be added to the statement I highlighted, and repaired.

ABX,
There is a thread about the proposed Cessna SID for some singles, and a number of posts about corrosion in strutted Cessna wings.
Read them carefully.
Just about any aircraft will have corrosion, if you didn't find any, you didn't look hard enough. Expect to pay a LAME about the cost of a 100h inspection to do a proper pre-buy --- because it will take as long as a 100h. --- any less will not be thorough enough.
Re. overhauling engines in Australia, where you have the overhaul done is the most important criteria, not the size of the overhauler's advertising budget. There is a rather disquieting variation in results.
Tootle pip!!