Stratoflex Hose Useful Life

Rob58

Pre-takeoff checklist
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What is the practical useful life for hydraulic hose such as Stratoflex 111? I have recently pulled a couple of hoses off my plane with date tags from 1959. They weren’t leaking but not very flexible either. Looking for feedback from the POA experts. Thanks!
 
I cant give you the number, but I’d bet its a lot less than 60 years.
 
I changed out all of my hydraulic hoses on my Aztec last year. Most were 17 years old. Found a couple that were original Piper from the 1979 manufacture date of the airplane.

Some people I've spoken with suggest they should be changed every decade, but that seems overkill for a private plane that will likely see few hours.
 
There is no set time by the faa, unless mandated by AD or ICA,as in the piper oil hoses. However, when inspecting, any leaking ,abrasion, or stiffening is grounds for rejection.
 
1959 is way too old. Not only are the years hard on that stuff, but the fluids slowly degrade it inside. And then there's the fact that some of the newer hoses are made of better stuff.

What's even scarier is the ancient hoses found firewall-forward. Fuel and oil hoses, baked thousands of times, carrying stuff that can be hot and/or hostile. Cessna recommends five years for Buna hoses and ten for teflon. Maybe a bit conservative, but 15 or 20 years? Who wants a hose failure in flight? Lose the airplane and your health, maybe your life, for the price of a few hoses?
 
1959 is way too old. Not only are the years hard on that stuff, but the fluids slowly degrade it inside. And then there's the fact that some of the newer hoses are made of better stuff.

What's even scarier is the ancient hoses found firewall-forward. Fuel and oil hoses, baked thousands of times, carrying stuff that can be hot and/or hostile. Cessna recommends five years for Buna hoses and ten for teflon. Maybe a bit conservative, but 15 or 20 years? Who wants a hose failure in flight? Lose the airplane and your health, maybe your life, for the price of a few hoses?

I'd like to think an overwhelming majority of aircraft owners are aware of the obvious issues involved with using critical parts subjected to high pressures and heat for over half a century, and wouldn't need advice regarding their replacement.
 
I'll repeat a story I've told somewhere (maybe here) recently. About 20 years ago, I visited a nearby airport where a fellow kept his P-51. When I went in his hangar, everything was covered with oil and he was deep in the belly of the P-51. Long story short, an oil hose had failed and the Merlin puked most or all of its oil. To the best of his knowledge, the hose had never been replaced.

Don't be that guy.

If it isn't a teflon lined hose, you probably owe it to yourself to replace it after 10 or so years.
 
1959 is way too old. Not only are the years hard on that stuff, but the fluids slowly degrade it inside. And then there's the fact that some of the newer hoses are made of better stuff.

What's even scarier is the ancient hoses found firewall-forward. Fuel and oil hoses, baked thousands of times, carrying stuff that can be hot and/or hostile. Cessna recommends five years for Buna hoses and ten for teflon. Maybe a bit conservative, but 15 or 20 years? Who wants a hose failure in flight? Lose the airplane and your health, maybe your life, for the price of a few hoses?
I might not have been clear on my original post. Of course I would never consider a 60 year old hose serviceable. I am working on a new-to-me aircraft and pulling all of the hoses preparing to replace any or all of them. All of your points are well taken and I have seen the leaching from the rubber on the inside of the hose that you mention. My question was very simply to get an opinion on a conservative useful hose life; I realize that some application of good judgment must be used in addition to reviewing the guidelines published by Parker (thanks Bell206). Thanks to all for the helpful feedback!
 
I'd like to think an overwhelming majority of aircraft owners are aware of the obvious issues involved with using critical parts subjected to high pressures and heat for over half a century, and wouldn't need advice regarding their replacement.
I'd like to think that, too, but finding such stuff suggests that either the owner is complacent, or doesn't know about it because his mechanic is complacent.

In aircraft maintenance we have the Dirty Dozen, the factors that lead to maintenance mistakes. Look at number 5:

1. Lack of communication
2. Distraction
3. Lack of resources
4. Stress
5. Complacency
6. Lack of teamwork
7. Pressure
8. Lack of awareness
9. Lack of knowledge
10. Fatigue
11. Lack of assertiveness
12. Norms
 
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In aircraft maintenance we have the Dirty Dozen, the factors that lead to maintenance mistakes. Look at number 5:
This is a good list Dan. My observation is that at least half of this list would apply to the problems with my aircraft (the several vintage planes that I own). My interpretation for "Complacency" is expanded to include laziness, incompetence, greed (do the minimum work to get paid the maximum $$ from the owner) and then simply a lack of integrity. Failing to replace a 60 year old hose is just one example. I know some really, really great mechanics so my comments are in no way meant to be a broad generalization. What troubles me is there seem to be a group of "shade tree" mechanics that gravitate to performing annual inspections on older, lower value aircraft, probably to meet the demand of owners who refuse to spend the money to properly maintain their planes. I can't begin to recall how many annual inspection logbook entries I have read that say nothing more than "serviced battery, performed landing gear retraction, repacked wheel bearings, verified ELT battery date, checked for AD compliance. I certify this aircraft to be in airworthy condition". Essentially they get paid to make a logbook entry. This is why I get deeply involved with the maintenance of my aircraft. This is why I ask a lot of questions on forums.
 
...I can't begin to recall how many annual inspection logbook entries I have read that say nothing more than "serviced battery, performed landing gear retraction, repacked wheel bearings, verified ELT battery date, checked for AD compliance. I certify this aircraft to be in airworthy condition". Essentially they get paid to make a logbook entry. This is why I get deeply involved with the maintenance of my aircraft. This is why I ask a lot of questions on forums.

Do you expect that every annual inspection include a complete rebuild of the airframe and overhaul of the engine before it's a legitimate annual inspection? Owners that pay thousands for an annual on a simple single engine had better be getting more than just an annual inspection. If it's just an annual inspection that you contract for, then the log book entry is all you're entitled to beyond the labor to access everything needing inspection, the IA's time to eyeball everything and then the labor to put everything back together. A logbook entry saying an annual was accomplished and a list of unairworthy items was provided is also a legitimate annual inspection and lets the owner operator choose how to clear those items. A mechanic or a mechanic with IA does not declare an aircraft unairworthy. The owner/operator determines the airworthiness of his aircraft based on input from pilots, mechanics and IAs. All they can do is identify unairworthy discrepancies and leave it to the owner/operator where to go from there. I guess most owner/operators choose to have the discrepancies fixed as they are identified and that's why logbook entries for an annual get wordy because additional maintenance is accomplished.
 
Do you expect that every annual inspection include a complete rebuild of the airframe and overhaul of the engine before it's a legitimate annual inspection? Owners that pay thousands for an annual on a simple single engine had better be getting more than just an annual inspection. If it's just an annual inspection that you contract for, then the log book entry is all you're entitled to beyond the labor to access everything needing inspection, the IA's time to eyeball everything and then the labor to put everything back together. A logbook entry saying an annual was accomplished and a list of unairworthy items was provided is also a legitimate annual inspection and lets the owner operator choose how to clear those items. A mechanic or a mechanic with IA does not declare an aircraft unairworthy. The owner/operator determines the airworthiness of his aircraft based on input from pilots, mechanics and IAs. All they can do is identify unairworthy discrepancies and leave it to the owner/operator where to go from there. I guess most owner/operators choose to have the discrepancies fixed as they are identified and that's why logbook entries for an annual get wordy because additional maintenance is accomplished.
Tim, my first impression of your comment is that you are talking down to me assuming I am an uninformed aircraft owner, ignorant of the role of the mechanic and of the annual inspection process. I am not. My apology if I have misinterpreted you message. I merely stated facts based on my 47 years of aircraft ownership: some A&P mechanics (including those with IA) certify airworthiness without performing an adequate or proper inspection. Perhaps I could have better worded my comment in post #11. I am well aware that an “annual inspection” does not imply that the same person is automatically engaged to perform any maintenance or repair work as part of the inspection process. Furthermore I am aware of my responsibility as the owner/operator. No doubt many aircraft owners are grossly ignorant concerning all aspects of aircraft maintenance. However some owners may have extensive and intimate knowledge of their aircraft even if they don’t possess the A&P license. I value the knowledge gained on the various aviation forums and appreciate that you have taken time to review this thread, which I initiated. --Rob
 
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Tim, my first impression of your comment is that you are talking down to me assuming I am an uninformed aircraft owner, ignorant of the role of the mechanic and of the annual inspection process. I am not. My apology if I have misinterpreted you message. I merely stated facts based on my 47 years of aircraft ownership: some A&P mechanics (including those with IA) certify airworthiness without performing an adequate or proper inspection. Perhaps I could have better worded my comment in post #11. I am well aware that an “annual inspection” does not imply that the same person is automatically engaged to perform any maintenance or repair work as part of the inspection process. Furthermore I am aware of my responsibility as the owner/operator. No doubt many aircraft owners are grossly ignorant concerning all aspects of aircraft maintenance. However some owners may have extensive and intimate knowledge of their aircraft even if they don’t possess the A&P license. I value the knowledge gained on the various aviation forums and appreciate that you have taken time to review this thread, which I initiated. --Rob

Thank you for a civil reply. My comment was based on the impression left in your post that the logbook entry you gave as an example was on its face value, indicative of a substandard inspection, a complacent owner, or both. The inspection entry was fine but I have no idea whether the inspector in fact did follow a checklist entailing the scope and depth of Part 43, Appendix D. I applaud your intimate familiarity with your aircraft and would encourage all owners to be involved with the maintenance of the aircraft they owned to the same extent you appear to be.
 
some A&P mechanics (including those with IA) certify airworthiness without performing an adequate or proper inspection. Perhaps I could have better worded my comment in post #11.
I had come to the same conclusion as witmo on your post 11 but now see it was in error. But as to your "group of "shade tree" mechanics" comment, so long as there are "shade tree" aircraft owners around those type of mechanics will continue to prosper. It was the reason that I went strictly owner-assisted as I was tired of the "shade trees" out there. And from your recent comments, it appears you are one of those owners I would have assisted.
 
But as to your "group of "shade tree" mechanics" comment, so long as there are "shade tree" aircraft owners around those type of mechanics will continue to prosper.
No question about it! Based on my observations bad mechanics represent a small percentage of the overall aircraft mechanic population. However the aircraft owner population... well that's a different story. There is a large group of dysfunctional people within our ranks. I appreciate your feedback for sure.
 
What is the practical useful life for hydraulic hose such as Stratoflex 111? I have recently pulled a couple of hoses off my plane with date tags from 1959. They weren’t leaking but not very flexible either. Looking for feedback from the POA experts. Thanks!
We uae PHT from Oklahoma for all of our hoses. Their service life is oil hoses 5 years or 1000 hrs. Teflon lined hoses 8 years or 1000 hrs. We routinely find hoses that are 25/ 35/ 45 years old and we replace them. Cessna 210's especially have hoses this age. Cessna service life is OH of the hydraulic power pack every 5 years. The last 15 C210's only one did NOT have the factory original power pack. That being said, so not to void the warranty on most power packs, and actuators they require hose replacement.
 
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