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Being practical with the homebuilt.vs. certified decision

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Dan Thomas

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Let me compliment you on your choice of a homebuilt (Bearhawk). Thats one of the benefits of a homebuilt, most everything is new and you don't have to deal with wear and tear creeping up on you from accumulated hours. I'm not knocking Cessnas, they had to be a heck of an airplane to accumulate so many hours...but now that they have accumulated all those hours you have to wonder when they become a liability. As you mentioned, fatigue cracks were found after the airplane was destroyed on the ground by high winds. You have to wonder why those cracks weren't discovered at the last inspection, and how long they had been spreading.
Maybe the wind destruction was a lucky thing after all. I would think that any annual inspection should include thorough inspection of all cables and pulleys not only on Cessnas but even homebuilts.

Excerpt from site below: " If you will notice, the lower bearing for the rudder is made into the bellcrank. It is quite common for the bearing to be extremely worn." Has this been dealt with on the
10,000 hr 150 that was inspected by the nonworking/father A&P and his GA knowledgeable friend? Look at the site and it has some good info. I would think it would be somewhat expensive to
deal with these repairs properly and that deciding when to replace it would be somewhat subjective ($$$).

Cessna 150 rudder inspection and modification.

Cessna publishes Service Bulletins all the time, many of them dealing with issues related to aging airplanes. Fatigue cracks are not unusual, and when Cessna sends out SBs we get serious about them and have a look, and sure enough, we might find exactly what they're talking about. It's no different from old cars with many miles on them. The 172 tends to crack at the bottom of the aft doorposts, where the post meets the gear box. The horizontal stab's forward spar cracks, as we've seen. Some models would crack the forward doorposts at the door lower hinge. The engine mount attach points inside the firewall sometimes crack inside the channel, where it's hard to see. A borescope catches that. The engine mounts of some would crack at the lower transverse tube welds. The mufflers and exhaust risers crack, but that's no different than many other airplanes. The carb air box falls apart. The flap cove skins and their stabilizing brackets in the wings will crack. The flap lower skins crack at the the trailing edges, through the rivet holes. The flap rollers cut the flap support arms and can cause failures. See, there's plenty of information for the serious maintainer. I would not be at all surprised to find fatigue cracks in airplanes maintained by people who don't pay attention to service bulletins.

As far as the 150's lower rudder bearing: there's an SB AND an AD on that regarding the rudder stops. ADs are too often overlooked.
 

ekimneirbo

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Cessna publishes Service Bulletins all the time, many of them dealing with issues related to aging airplanes. Fatigue cracks are not unusual, and when Cessna sends out SBs we get serious about them and have a look, and sure enough, we might find exactly what they're talking about. It's no different from old cars with many miles on them. The 172 tends to crack at the bottom of the aft doorposts, where the post meets the gear box. The horizontal stab's forward spar cracks, as we've seen. Some models would crack the forward doorposts at the door lower hinge. The engine mount attach points inside the firewall sometimes crack inside the channel, where it's hard to see. A borescope catches that. The engine mounts of some would crack at the lower transverse tube welds. The mufflers and exhaust risers crack, but that's no different than many other airplanes. The carb air box falls apart. The flap cove skins and their stabilizing brackets in the wings will crack. The flap lower skins crack at the the trailing edges, through the rivet holes. The flap rollers cut the flap support arms and can cause failures. See, there's plenty of information for the serious maintainer. I would not be at all surprised to find fatigue cracks in airplanes maintained by people who don't pay attention to service bulletins.

As far as the 150's lower rudder bearing: there's an SB AND an AD on that regarding the rudder stops. ADs are too often overlooked.
Dan, if someone owns an older Cessna that had been annualed say three months ago and the owner of the airplane ...after reading some of this thread...decided he had second thoughts about how thorough his
annual inspection was...and whether all the applicable safety modifications may have been performed on his aircraft.....then what would be the best way to insure his airplane was safe?

Where could he get a comprehensive list of things to inspect and be sure that all things had been complied with? While the owner cannot effect the upgrades or repairs, it might be of interest to perform his own
cursory inspection to insure nothing had been overlooked. Does Cessna provide some type of updated chart on things to inspect for that is available to all A&Ps or do they just have to compile their own list and
hope they didn't miss some Service Bullitin?
 

djschwartz

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Dan, if someone owns an older Cessna that had been annualed say three months ago and the owner of the airplane ...after reading some of this thread...decided he had second thoughts about how thorough his
annual inspection was...and whether all the applicable safety modifications may have been performed on his aircraft.....then what would be the best way to insure his airplane was safe?

Where could he get a comprehensive list of things to inspect and be sure that all things had been complied with? While the owner cannot effect the upgrades or repairs, it might be of interest to perform his own
cursory inspection to insure nothing had been overlooked. Does Cessna provide some type of updated chart on things to inspect for that is available to all A&Ps or do they just have to compile their own list and
hope they didn't miss some Service Bullitin?
An IA pays for a subscription to the ADs. Any reputable IA should be able to look up all the ADs and service bulletins for you aircraft. That's a required part of an annual. If you doubt the IA's efforts in this regard then I would also be suspicious of other aspects of the "annual" he performed and I would find another IA.

Compliance should be listed in the aircraft log books. You can also order a CD of all records for the aircraft from the FAA. It's quite inexpensive and will contain digitized copies of all 337s file on that aircraft for major repairs and alterations among other things. If there is no record of compliance with an AD or SB but compliance can be verified by inspection then all that is required is for an A&P or IA to make a note in the logs that the work was done in the past by persons unknown and compliance has been verified.
 

TFF

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I have worked on a couple of aircraft that had not had required ADs done or removed AD compliance by putting on junk parts. There are plenty of aircraft out there that are a mess, and they have spent the last 20 years flying patterns at their airport. $100 whipped annuals. You have to know what you are looking at. If a plane has been sitting in a hangar for 20 years, there are some AD updating for sure, some might not be cheap. Good pre-buy with someone who knows the brand is hard to beat. All the ADs are now on the FAA site; although I use a subscription, not required anymore because on FAA site. ADs are required by regulation. Service Bulletins may be required by the manufacturer, but there is no regulatory requirement to do them. The FAA does not care about them without an AD attached. They are a window to what is not in the Maintenance manual, but like it or not, up to owner to have them done or not. A&P quitting the project because wanting to do them has nothing to do with the law. 99% of owners want the relevant ones done, so not much of a problem. Cirrus even rates them from "we want you to do them, to if everyone does not do them, the FAA will make it an AD." Not doing a service bulletin may void your insurance though, because they will do anything to not pay off a claim. More legal fun is answering who is responsible for the ADs getting done? The pilot per the FARs; actually in the PPL question list. Before he flies the aircraft, he is suppose to know the status of all the ADs; it is his fault for taking off with bad AD compliance. The Mechanic or IA is responsible for doing the ADs correctly, and by being asked to do the inspection, looking into what ADs are suppose to be done. Assuming no foul play, pilot is in more responsible for bad AD compliance.
 

Dan Thomas

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TFF;286935 More legal fun is answering who is responsible for the ADs getting done? The pilot per the FARs; actually in the PPL question list.[/QUOTE said:
The pilot responsible? Maybe in the U.S., but in Canada it's the owner of the aircraft.

Transport Canada's website has an AD function in which you enter your aircraft's registration, and it spits our the relevant airframe, engine and propellers ADs. It doesn't catch the appliance ADs, so the mechanic has to think about what equipment might be affected. Certain instruments, wheels and brakes, ignition switches, radios, alternators or generators, magnetos (lots of ADs on mags), vacuum pumps, seat belts, and so on. A decent AD search can take several hours, to determine relevant ADs and the aircraft's compliance status.

ADs are free on the FAA website. I don't know whay anyone would pay a subscription anymore.

If a guy has an old Cessna and is concerned about how it's been inspected, he can take it to a Cessna dealer's shop where the guys familiar with the type can look at it. They have all the Cessna manuals and Service Bulletins and Service Letters and so on. Other shops can also subscribe to this stuff but it's not cheap, and bargain-basement mechanics don't buy it. You get what you pay for, basically, and way too many airplanes have had some pretty cursory annuals that end up costing a new owner big bucks when a better mechanic looks at it. He might have been better off buying a newer airplane that had been looked after more carefully. An owner can tell the mechanic to leave defects alone, but that info will go into the airplane's logs to protect the mechanic.

If an owner is concerned about safety, he will have to pay more for better service and more thorough inspections. There is no way around it. I sure don't know of any good mechanics that work for free.
 

TFF

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In US, owner or operator; stand corrected and caught. Where I messed up was, of course, knowing not going to be commercial and not being corporate flying. Pilot and owner not necessarily the same, for being the top for responsible for maintenance. I dont pay for a fancy service; I actually share it with someone. Nice Word forms generated. I'm not a typer, so it really takes a lot of hate out of making the list.
 
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