Fuel hose

[Warmi]

I need to replace a short section of fuel hose ( in the cabin so basically between the tank and the aux fuel pump  ) - I think it seems like this hose should work at 5/16 - any better options perhaps  ?
 

https://www.aircraftspruce.com/catalog/appages/parkersuperflex.php

 

Thanks

[Roger Lee]

You can buy 5/16" ID hose locally from an auto parts store. You can make it either fuel injection or carburetor (vapor recovery) hose. I prefer the carb hose for carb engines and only fuel injection for the 912iS engine. I use Gates hose same as Rotax. They use Gates in Europe on the Rotax.

[Jim Meade]

Please wait while I pop a batch of popcorn.

[Tom Baker]

A Sting I just worked on had the Parker Super Flex. I did a wing pull, and the 5/16 hose seemed to fit the connections just fine. I did not have any other connections loose. 

 

[Roger Lee]

There is more than one company that makes adequate hose for our fuel system. Companies i.e. Gates and Parker plus many more. This may also depend where in the world you live. Then you have Teflon hose.

[Tom Baker]

Roger, when you reference "our" airplanes I can only assume that you mean the CT series, because this is the CT forum. The OP owns a Sting S4, not a CT, that is why I referenced the hose on the Sting I recently worked on. 

Also adequate is not the right word to use when selecting fuel hose, the word the FAA uses in these situations is acceptable. You need to determine if the hose is acceptable. Considering the construct of the ASTM standards and the FAA acceptance this puts approval of the hose in the hands of the manufacture. Any hose that is listed in the parts manual by specification and size would be acceptable. Any hose that has been approved through a manufacture approval, like the 1" safety stripe heater hose in place of the 25mm coolant hose would be acceptable. The last option for acceptable is an individual MRA approval for the hose installation on the airplane. Using a hose that does not fall under these three choices for fuel hose would not be acceptable, even it you think it is adequate. 

 

[Warmi]

The reason I asked is because …

- for one, there is no specific Sting forum

- our planes share the same engine so pretty much 95% of engine related info is derived from Rotax recommendations and is applicable to both 

[Tom Baker]

3 minutes ago, Warmi said:

The reason I asked is because …

- for one, there is no specific Sting forum

- our planes share the same engine so pretty much 95% of engine related info is derived from Rotax recommendations and is applicable to both 

Rotax uses, or at least they used to use, 5/16" hose that was factory attached to the fuel pump on the inlet side, and 1/4" on the outlet side. On some airplanes the hose from the splitter to the carburetors is a Rotax part, and others they do their own thing. Other than that the aircraft manufacture chooses the hose size and specification. I would recommend using what the manufacture list in their maintenance manual, parts catalog, or other manufacture's approved document unless you are experimental. 

[Roger Lee]

"our planes share the same engine so pretty much 95% of engine related info is derived from Rotax recommendations and is applicable to both"

Correct. There is nothing special on an FD vs the Sting 912UL or ULS Rotax. You can use the same fuel hose. I do at least a dozen or more hose changes on all kinds of LSA every year and just use Gates 1/4" & 5/16" carb fuel hose unless I work on a 912iS and that requires several form fitted specific hose and some 3/8" in places.

Rotax uses Gates fuel hose just made in Europe in metric. This has changed some over the past couple of years with other types of hose in certain areas. The 17mm coolant hose is made by Conti-Continental.  

Tom,

Remember in the maintenance manual and an SB that you are allowed to use an Equivalent  because Rotax just names and uses things from the European market. These things are not accessible around the world.

This is just like Loctite 5910 for the gearbox RV seal. Here in the US we use Loctite 598. It is the equivalent. 

[Tom Baker]

1 hour ago, Roger Lee said:

Tom,

Remember in the maintenance manual and an SB that you are allowed to use an Equivalent  because Rotax just names and uses things from the European market. These things are not accessible around the world.

This is just like Loctite 5910 for the gearbox RV seal. Here in the US we use Loctite 598. It is the equivalent. 

Roger, I am not quite sure where you are going with this. The excerpted notation in the Rotax manual would make substituting equivalent consumable materials to those on that list acceptable. Trying to bootstrap that in to making substitutions for parts specified by the aircraft manufacture for the airframe is not acceptable. 

[Roger Lee]

So call FD and ask for that specific hose part number that matches the parts manual exactly and not something they substituted. How do you think I got all those LOA's done in the first place. FD doesn't order everything or use everything imported from Europe plus FD didn't use what Rotax specifically specified in their manual. Even now FD uses what they can get that is a fairly equal substitute since they can't and don't buy only specified hoses from Europe. You think all the FD and Rotax service centers in the US use the exact same hose from the same vender in Europe. I know for a fact they don't. I see it all the time and see their substitutions. FD says follow Rotax and Rotax says you can substitute. Order a hose kit from one service center and then from another and they will most likely be different.

If you only tried to buy what's specifically in the parts manual you wouldn't be able to complete all your jobs.

[Tom Baker]

11 hours ago, Roger Lee said:

So call FD and ask for that specific hose part number that matches the parts manual exactly and not something they substituted. How do you think I got all those LOA's done in the first place. FD doesn't order everything or use everything imported from Europe plus FD didn't use what Rotax specifically specified in their manual. Even now FD uses what they can get that is a fairly equal substitute since they can't and don't buy only specified hoses from Europe. You think all the FD and Rotax service centers in the US use the exact same hose from the same vender in Europe. I know for a fact they don't. I see it all the time and see their substitutions. FD says follow Rotax and Rotax says you can substitute. Order a hose kit from one service center and then from another and they will most likely be different.

If you only tried to buy what's specifically in the parts manual you wouldn't be able to complete all your jobs.

Actually Airtime carries the OEM Wurth fuel hose imported from Europe. The parts manual provides a specification and size for the hoses. It is not that hard to source them here in the states. I have been doing it for 15 years without issues. Rotax doesn't give carte blanche on substitution, it is very specific that it applies to the consumables list. Flight Design doesn't say to follow Rotax, they say to refer to Rotax for maintenance on the engine. Trying to use Rotax's substitution of consumable materials to make substitutions on airframe parts is a really big stretch, and I don't think it would meet the acceptable standards. Honestly, I can not think of any valid reason for not using the correct parts. 

 

[Roger Lee]

" I have been doing it for 15 years without issues."

So you're saying you bought parts from some place else when FD had a part number which then is supposed to come from only FD?

So what's the difference . FAA says if it has a specific part number it must come from FD / aircraft Mfg.

The Rotax service centers do it.  I've seen it in person. FD has done it over the years too with different items.

[Tom Baker]

20 minutes ago, Roger Lee said:

" I have been doing it for 15 years without issues."

So you're saying you bought parts from some place else when FD had a part number which then is supposed to come from only FD?

So what's the difference . FAA says if it has a specific part number it must come from FD / aircraft Mfg.

The Rotax service centers do it.  I've seen it in person. FD has done it over the years too with different items.

Roger, I have been an aircraft mechanic since 1983, with inspection authorization since 1990. I have been working on airplanes and dealing with the FAA most of my adult life. You are correct in that parts listed in the parts catalog with manufacture part numbers need to come from the manufacture. But there is an exception to that rule depending on how the part description is written. For example in the attached nav light PDF the lights should come from Flight Design, but the hardware can come from anyplace as long as it meets the specification and size. In the attached fuel system parts list any of the parts where a specification and size are provided can be sourced from other than the manufacture. Any parts that don't have a specification should come from Flight Design. Now if there was a part number, and the description just said fuel hose, then it would need to come from Flight Design. An example from the standard category world is wheel bearings. Piper and Cessna both use Cleveland wheels and brakes. The wheels use identical wheel bearings. Cessna has their part number, and the description just says wheel bearing. Piper has their part number, and the description is Timken bearing XYZ. For the Cessna you are supposed to buy the bearing from Cessna, or some other source that has a PMA bearing for that model airplane. For the Piper you can buy the Timken XYZ bearing from any where. 

 

nav lights.pdf Fuel system parts.pdf

[Madhatter]

1 hour ago, Tom Baker said:

Roger, I have been an aircraft mechanic since 1983, with inspection authorization since 1990. I have been working on airplanes and dealing with the FAA most of my adult life. You are correct in that parts listed in the parts catalog with manufacture part numbers need to come from the manufacture. But there is an exception to that rule depending on how the part description is written. For example in the attached nav light PDF the lights should come from Flight Design, but the hardware can come from anyplace as long as it meets the specification and size. In the attached fuel system parts list any of the parts where a specification and size are provided can be sourced from other than the manufacture. Any parts that don't have a specification should come from Flight Design. Now if there was a part number, and the description just said fuel hose, then it would need to come from Flight Design. An example from the standard category world is wheel bearings. Piper and Cessna both use Cleveland wheels and brakes. The wheels use identical wheel bearings. Cessna has their part number, and the description just says wheel bearing. Piper has their part number, and the description is Timken bearing XYZ. For the Cessna you are supposed to buy the bearing from Cessna, or some other source that has a PMA bearing for that model airplane. For the Piper you can buy the Timken XYZ bearing from any where. 

 

nav lights.pdf 99.27 kB · 1 download Fuel system parts.pdf 181.84 kB · 5 downloads

Try to buy bearings from a Timken distributor for Piper or any aircraft,  they won't sell them to you, I've been there recently. I found it cheaper to buy better certified wheels for a cub instead of rebuilding the originals, the bearings were $200. Everyone used to buy small GA aircraft bearings from Timken years ago but now you can't. It's about money. My cub was built to a different regulatory standard which allows me to do things you can't do on later aircraft when it comes to maintenance but I still can't buy bearings the way it was always done. Again it's about money, and also beurocracy. 

 

[Anticept]

If a spec is provided, you can get any product that meets that spec. That's why we can use fuel that meets a min 91 AKI, and not required to buy specifically shell gasoline. Same with oils, coolants, wires, solder, crimp connections, etc. Some of this is covered by it just being industry standard (in standard airworthiness aircraft). S-LSA on the flip side is more stringent. But this is still in common.

If a part number is provided, you have to source that part number. As Tom said, if it's a timken part number... You can buy it from timken (if they were to sell it to you).

The importance is if it's a flight design part number... Then only flight design is the source.

If it's a rotax part number... You have to use rotax parts.

 

Will the FAA come rolling in because you used the wrong hose? Not by itself. But if there's a fatality, and that hose was found to have been the failure, there's no amount of proof you could provide that it's a reasonable substitute. The rules aren't written like that. Either it's acceptable/approved, or it's not.

[Roger Lee]

 

FD changed hundreds of parts and it never made the manuals.

So what you guys are telling me is you've never ever substituted any part on a CT and you have ALWAYS purchased your parts from FD without exception because they all have part numbers in the parts manual. You buy all your tires from them, you never used an Odyssey  battery, you buy all your nuts and bolts from them because FD has specific part numbers and the list goes on. You guys have bought parts that were not ordered from an Mfg or a perfect match to another part? Kind of like ordering front suspension dampeners, door lift struts, front suspension pins and CTSW engine mounts from me? Those are all FD specific numbered parts in the parts manual.

In the LSA industry you guys are picking and choosing at times what can and can't be done and or parts over the years. FD and other LSA Mfg's don't follow those rules either. They all substitute and so do Rotax service centers.  I know I've worked with them and bought from them. They do what they need to do and it isn't always identical to the book. I know this because I have many friends in all those places.

You can't just pick and choose. It's either all in or not. Probably 98% not over the years, not..

Just like the Timken wheel bearing. During my research project on these things the FAA said they know many do buy from the aircraft Mfg, buy buy the same bearing from somewhere else.

[Roger Lee]

"They're supposed to also spec the fuse, but the SB just says use the size for the charging current that you expect.

Regardless it's good enough, nobody's going to raise a stink.'

See Corey.

[Tom Baker]

10 hours ago, Roger Lee said:

So what you guys are telling me is you've never ever substituted any part on a CT and you have ALWAYS purchased your parts from FD without exception because they all have part numbers in the parts manual. You buy all your tires from them, you never used an Odyssey  battery, you buy all your nuts and bolts from them because FD has specific part numbers and the list goes on. You guys have bought parts that were not ordered from an Mfg or a perfect match to another part? Kind of like ordering front suspension dampeners, door lift struts, front suspension pins and CTSW engine mounts from me? Those are all FD specific numbered parts in the parts manual.

No I don't buy tires from them because of the manufacture approval attached. This makes installing this type of tire acceptable. I use Odyssey batteries because of the manufacture approval for Odyssey batteries attached. This makes it acceptable. I don't buy hardware from them, as long as it meets the DIN specification and size listed in the part description, which is acceptable. The parts catalog provides a manufacture and size for the engine mount rubber. Buying this specific part from any source is acceptable. The nose suspension dampers are a specification as well. If the ones you are selling meet that specification then all is well, because that is acceptable. I do my best to make sure the parts I install are acceptable by buying Flight Design parts when necessary, using previous manufacture approvals, using the specification and size in the part's description, or getting a MRA. 

 

08 04 10 FD Manufacturer Approval for all CTSW, CTLS_Tires.pdf 08 05 12 FD Manufacturer Approval for all CTSW and CTLS battery (2).pdf

[Anticept]

Even if someone else plays it fast and loose, it doesn't mean that we can.

They're supposed to keep that information up to date. It's part of their responsibility to maintain airworthiness.

To my point, that's how the laws and regs are written.

To Tom's credit: he has the part sources readily available for the hose, it's not like he's performing arcane arts to source those parts, so people should be using those parts, there really isn't an excuse not to other than convenience.

All that said, I do get it, some of this stuff is beyond rediculous and the mechanic shouldn't have to be the one getting stuck in the gaps. If this were standard airwortiness aircraft, this wouldn't be such a problem, because there are some lovely regs in part 23 that enable substitutions of certain parts by the mechanic.

This is part of my decision to go E-LSA. I'm done with the silliness of S-LSA. There's things I like about S-LSA but the parts and maintenance procedures is not one of them. There are a few S-LSAs that say "43.13 practices are acceptable" in their manuals and I wish flight design said it, it would help a lot.

 

[Tom Baker]

12 hours ago, Madhatter said:

Try to buy bearings from a Timken distributor for Piper or any aircraft,  they won't sell them to you, I've been there recently. I found it cheaper to buy better certified wheels for a cub instead of rebuilding the originals, the bearings were $200. Everyone used to buy small GA aircraft bearings from Timken years ago but now you can't. It's about money. My cub was built to a different regulatory standard which allows me to do things you can't do on later aircraft when it comes to maintenance but I still can't buy bearings the way it was always done. Again it's about money, and also beurocracy. 

 

It was an example to make a point. I remember the discussion from an IA renewal meeting years ago.

[FlyingMonkey]

42 minutes ago, Anticept said:

This is part of my decision to go E-LSA. I'm done with the silliness of S-LSA. There's things I like about S-LSA but the parts and maintenance procedures is not one of them. There are a few S-LSAs that say "43.13 practices are acceptable" in their manuals and I wish flight design said it, it would help a lot.

Concur 100%.  The idea of the ATSM standards and the SLSA category was to make maintenance more affordable and easy to manage, for the FAA, manufacturers, and owners, while still retaining some standards that would keep everything safe and reasonable.  Unfortunately the SLSA makers use the rules to impose a parts stranglehold on owners and make everything more expensive than it otherwise could (and should) have been.  That's one big reason the dream of $60-75k new SLSA never really materialized.

Conversely, I am actually thrilled with the ELSA rules.  It's even more flexible than EAB in many ways, like allowing a non-builder to take a weekend course and do conditional inspections on an airplane they own.  I did the math and in the first year of going ELSA I saved over $3000 (condition inspection, hose change, and some other odds and ends).  I understand that doing maintenance isn't for everybody, but the beauty of ELSA is that you can do whatever you feel comfortable with and farm out the rest to a mechanic.  And you're never stuck with an airplane down for weeks because you need a few wrenches turned that you could easily do yourself but you have to wait on a mechanic to do it.  Plus the obvious parts substitution advantages where it makes sense and/or could actually improve things.

[Madhatter]

ELSA is the only way to go and it should not devalue the aircraft depending on who does the work. I probably have the most modified SW in the world and all of the modifications were done in accordance with accepted practices and technology for aircraft. Some things take a lot of research and effort and not everything is successful to do, but it can make a much better aircraft. Someone came in my hangar not long ago and commented that I just can't leave things alone. I guess not for the last 50 years.

 

[procharger]

FD is buying their fuel hoses from somebody pretty sure they don't make their own.

[Anticept]

They do, but without that spec in acceptable documentation, we can't legally put it in.

I hate rebranded parts as much as the next person but that's the way it is.