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External Brake Lines - crack
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etandrews(at)westnet.com.
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PostPosted: Wed Jul 06, 2011 2:51 pm    Post subject: External Brake Lines - crack Reply with quote

Everyone,

I have found a fatigue crack in one of my external brake lines just outside the fuselage where the aluminium tube curves back to the gear leg. I noticed my brake fluid down on the left hand side after my flight and then went to investigate. On my previous flight, I had inspected the wheel region and pumped up the tires and no leak was evident... so the final failure must have occurred on my last flight. I am now planning to replace the solid aluminium tube with flexible hoses as per Tim’s web page. For the last 18 months I have operated out of a grass airfield that I expect has contributed to the extra movement in the gear during taxi and landing etc.

Has anyone found any issues with use of flexible brake hoses and if so what hose type did you use?

Evan Andrews
RV10 150hrs Flying








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speckter(at)comcast.net
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PostPosted: Wed Jul 06, 2011 3:50 pm    Post subject: External Brake Lines - crack Reply with quote

I too fly on grass and had the same issue as you. I replaced them with Bonaco. They have the lengths you need, you don’t even have to measure.

Gary Specketer


From: owner-rv10-list-server(at)matronics.com [mailto:owner-rv10-list-server(at)matronics.com] On Behalf Of E & T Andrews
Sent: Wednesday, July 06, 2011 5:47 PM
To: rv10-list(at)matronics.com
Subject: External Brake Lines - crack


Everyone,



I have found a fatigue crack in one of my external brake lines just outside the fuselage where the aluminium tube curves back to the gear leg. I noticed my brake fluid down on the left hand side after my flight and then went to investigate. On my previous flight, I had inspected the wheel region and pumped up the tires and no leak was evident... so the final failure must have occurred on my last flight. I am now planning to replace the solid aluminium tube with flexible hoses as per Tim’s web page. For the last 18 months I have operated out of a grass airfield that I expect has contributed to the extra movement in the gear during taxi and landing etc.



Has anyone found any issues with use of flexible brake hoses and if so what hose type did you use?



Evan Andrews

RV10 150hrs Flying






















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Bill Schlatterer



Joined: 09 Jan 2006
Posts: 195

PostPosted: Wed Jul 06, 2011 4:05 pm    Post subject: External Brake Lines - crack Reply with quote

Bonoco will have the lines ready made for your make and model. Super quality with abrasion sleeving over braid. Using them on my 7 and love them. 50 hours and no apparent wear at all.

Bill S
7a

From: owner-rv10-list-server(at)matronics.com [mailto:owner-rv10-list-server(at)matronics.com] On Behalf Of E & T Andrews
Sent: Wednesday, July 06, 2011 5:47 PM
To: rv10-list(at)matronics.com
Subject: External Brake Lines - crack

Everyone,

I have found a fatigue crack in one of my external brake lines just outside the fuselage where the aluminium tube curves back to the gear leg. I noticed my brake fluid down on the left hand side after my flight and then went to investigate. On my previous flight, I had inspected the wheel region and pumped up the tires and no leak was evident... so the final failure must have occurred on my last flight. I am now planning to replace the solid aluminium tube with flexible hoses as per Tim’s web page. For the last 18 months I have operated out of a grass airfield that I expect has contributed to the extra movement in the gear during taxi and landing etc.

Has anyone found any issues with use of flexible brake hoses and if so what hose type did you use?

Evan Andrews
RV10 150hrs Flying








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rv10flyer



Joined: 25 Aug 2009
Posts: 364

PostPosted: Thu Jul 07, 2011 4:49 am    Post subject: Re: External Brake Lines - crack Reply with quote

Bonaco on mine.

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PostPosted: Thu Jul 07, 2011 9:50 am    Post subject: External Brake Lines - crack Reply with quote

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]--> Tim,

I was looking at your website and noticed that your original brake line installation went directly to the caliper. Did that work OK? Why did you loop around the axle on your Bonaco line install?

Roger
40291
[quote] ---


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Tim Olson



Joined: 25 Jan 2007
Posts: 2872

PostPosted: Thu Jul 07, 2011 10:10 am    Post subject: External Brake Lines - crack Reply with quote

My original lines were flex too. I routed them in the loop
because I wasn't thinking clearly and was being an
idiot. It works fine, but with flex, you could just go down
the leg and turn to the caliper. I did it to mimic the
loop with the hard lines....which of course we now
all know aren't holding up well. I've heard from quite
a few folks with breaks in those hard lines, especially
up near the fuselage for some reason.

If you just order the standard bonaco lines you'll be fine.
Don't be an idiot like me.

Tim Olson - RV-10 N104CD
do not archive
On 7/7/2011 12:46 PM, Roger Standley wrote:
[quote] Tim,
I was looking at your website and noticed that your original brake line
installation went directly to the caliper. Did that work OK? Why did you
loop around the axle on your Bonaco line install?
Roger
40291

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robin(at)PaintTheWeb.com
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PostPosted: Thu Jul 07, 2011 10:34 am    Post subject: External Brake Lines - crack Reply with quote

You're not an idiot you are an early adopter & pioneer.

Robin
Do Not Archive

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taildragon(at)msn.com
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PostPosted: Thu Jul 07, 2011 10:43 am    Post subject: External Brake Lines - crack Reply with quote

<?xml:namespace prefix="v" /><?xml:namespace prefix="o" /><![endif]--> So you are recommending to forget the axle loop and go direct to the caliper with the Bonaco flex line? Do you know the length of the standard bonaco lines? I believe yours were 46" with the loop.

Thank you!

Roger
40291



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dave.saylor.aircrafters(a
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PostPosted: Thu Jul 07, 2011 10:47 am    Post subject: External Brake Lines - crack Reply with quote

One of my original hard lines broke the other day at the caliper. I
used a local hose shop to fab new flex lines since we were leaving on
a trip and in a hurry. Definitely a weak spot.

Dave Saylor
AirCrafters
140 Aviation Way
Watsonville, CA 95076
831-722-9141 Shop
831-750-0284 Cell

On Thu, Jul 7, 2011 at 11:07 AM, Tim Olson <Tim(at)myrv10.com> wrote:
[quote]

My original lines were flex too.  I routed them in the loop
because I wasn't thinking clearly and was being an
idiot.  It works fine, but with flex, you could just go down
the leg and turn to the caliper.  I did it to mimic the
loop with the hard lines....which of course we now
all know aren't holding up well. I've heard from quite
a few folks with breaks in those hard lines, especially
up near the fuselage for some reason.

If you just order the standard bonaco lines you'll be fine.
Don't be an idiot like me.

Tim Olson - RV-10 N104CD
do not archive
On 7/7/2011 12:46 PM, Roger Standley wrote:
>
> Tim,
> I was looking at your website and noticed that your original brake line
> installation went directly to the caliper. Did that work OK? Why did you
> loop around the axle on your Bonaco line install?
> Roger
> 40291
>
>    ---


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PostPosted: Thu Jul 07, 2011 11:03 am    Post subject: External Brake Lines - crack Reply with quote

Well I truly believe that one reason that Vans has so many solid line issues is the product they ship. I would never use 301 based lines in anything on an airplane. So I will order 5052 alum tubing for all my fluid lines I need to make and will for sure go with Branco flex lines for the lines on the gear legs and to the calipers.

I have heard to darn many issues with vans tubing provided in the kits, from broken fuel lines to leaking fuel lines. I do not understand the going cheap on materials for a kit that has so much relying on it. Like peoples lives.

Just my 2 cents worth

John Cumins
A&P should be a IA if I get off my butt. Wow 31 years now.
40864 Emp done Wings working on skins
Sweeting in the 100 degree heat

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Tim Olson



Joined: 25 Jan 2007
Posts: 2872

PostPosted: Thu Jul 07, 2011 11:10 am    Post subject: External Brake Lines - crack Reply with quote

Yeah, I don't see the need for a loop if you're using flex.
I don't know the standard length, but I'm sure they're
shorter than mine. You could fabricate something similar
to use as a model, but Bonaco knows the length you'd need
so I'd just have them sell you the standard. I don't
know the measurement on the standard ones.

Tim Olson - RV-10 N104CD
do not archive
On 7/7/2011 1:38 PM, Roger Standley wrote:
[quote] So you are recommending to forget the axle loop and go direct to the
caliper with the Bonaco flex line? Do you know the length of the
standard bonaco lines? I believe yours were 46" with the loop.
Thank you!
Roger
40291
---


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rv10flyer



Joined: 25 Aug 2009
Posts: 364

PostPosted: Thu Jul 07, 2011 11:49 am    Post subject: Re: External Brake Lines - crack Reply with quote

31 1/2" -3 hose with -4 straight fittings on each end. Like Tim said they know exactly what you need. Everything fit fine on mine. The two hoses from copilot master cylinders to reservoir tee fitting were 1" too long but they still worked.

+1 for 5052-O fuel/brake lines. Van's 3003-O is going to be hauled off for scrap this winter after flying. 5052-O would have broken too...it just takes twice as long.

Back to wheel pants...oh I love fiberglass. At least the end is near as my pile of parts is getting real small. Ted Chang's BIG West trip on VAF has really got me motivated now. Looking forward to some cool fall test flying.


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PostPosted: Fri Jul 08, 2011 9:10 pm    Post subject: External Brake Lines - crack Reply with quote

Many thanks everyone for your input. Vans should consider including the
flexible hose lines in the RV10 kit... has this been raised with Vans
before?

all the best

Evan Andrews

VH-OSH Flying 154hrs

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maca2790



Joined: 26 Jan 2011
Posts: 59
Location: Australia

PostPosted: Sat Jul 09, 2011 12:27 am    Post subject: External Brake Lines - crack Reply with quote

G'day Evan,
just thought I would say hello. Good to see another Aussie builder. I'm
currently working on
The brake lines myself and I was looking at the plans and thought that the
solid lines going down
The gear leg was not an ideal way to do it.

Cheers

John MacCallum
Builder # 41016
VH-DUU

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flysrv10(at)gmail.com
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PostPosted: Sat Jul 09, 2011 2:40 am    Post subject: External Brake Lines - crack Reply with quote

I have been reading about the solid break lines and I wanted to tell everyone about my experience that seems to be completely different than what the group is thinking.

I have constructed my break lines solid all the way to the calipers on my RV6 with 1300 hrs of time and perhaps 800-900 landings and my RV10 with 530 hrs of time and 400 landings.

Both planes have not had any failures. I think that if you use the right faring tool and take care not to have nicks and cracks, solid lines work just fine. After all, having less part count, in principal, is not a bad idea.

Do not archive.

On Jul 9, 2011, at 4:23 AM, John MacCallum wrote:

[quote]

G'day Evan,
just thought I would say hello. Good to see another Aussie builder. I'm
currently working on
The brake lines myself and I was looking at the plans and thought that the
solid lines going down
The gear leg was not an ideal way to do it.

Cheers

John MacCallum
Builder # 41016
VH-DUU

--


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Kelly McMullen



Joined: 16 Apr 2008
Posts: 1188
Location: Sun Lakes AZ

PostPosted: Sat Jul 09, 2011 6:27 am    Post subject: External Brake Lines - crack Reply with quote

Van's would consider adding flex lines about the same time as they
consider stocking the correct nose wheel. They won't change the nose
wheel even though the correct one is exactly the same price. Flex
lines could add over $100 to the cost, especially if you include flex
lines in place of the crummy nylon lines in the cabin. Somehow we have
been deluded into wanting durability similar to certified
aircraft................what a crazy idea.

On Fri, Jul 8, 2011 at 10:06 PM, E & T Andrews <etandrews(at)westnet.com.au> wrote:
  Vans should consider including the
Quote:
flexible hose lines in the RV10 kit... has this been raised with Vans
before?

all the best

Evan Andrews


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PostPosted: Sat Jul 09, 2011 7:58 pm    Post subject: External Brake Lines - crack Reply with quote

Kelly,
I beg to differ but in certified aircraft that I am familiar, (Cessna)
flexible lines are used only where absolutely necessary. The
preference by certified aircraft designers is to use hard lines as
much as practicable if only so that there is no life limit on the
line.

This was driven home to me when I stood on the rear door of a C-17 and
looked up at all the hydraulic plumbing. With all those movable parts
and doors, NOT a single flexible line --not even at the actuators.
Where the line required movement, solid lines with mechanical (banjo
style) flexible fluid couplings were used. I took a picture of it but
I have to find it.

I know some Pipers use a short flexible line between their fuel tanks
and the fuselage fuel coupling. However on the Cardinal that; when in
doubt I ask "what would Cessna do" just as with Vans, flexible lines
are kept to a minimum and used only where absolutely necessary.

In the Cardinal fuel system, there are NO flexible lines. In the
Cardinal electro-hydraulic gear system there are only four short
flexible lines at the nose and main gear actuators. In the
retractable gear Cardinal, the brake line in the main gear is a solid
line. A the top of the RG brake line is a solid mechanical swivel
fitting and only on the lower portion by the wheel is a short easily
replaced flexible line used--remember this is a retractable gear
aircraft.

The point in all this is that hard lines ARE the standard in the
certified and military world in most areas and flexible lines are the
exception. Flexible lines are used only where hard lines are
impractical or expensive such as the movable mechanical (banjo type)
fluid connectors.

Just an alternative $0.02.

William
N237VX
On Jul 9, 2011, at 10:25, Kelly McMullen <apilot2(at)gmail.com> wrote:

Quote:


Van's would consider adding flex lines about the same time as they
consider stocking the correct nose wheel. They won't change the nose
wheel even though the correct one is exactly the same price. Flex
lines could add over $100 to the cost, especially if you include flex
lines in place of the crummy nylon lines in the cabin. Somehow we have
been deluded into wanting durability similar to certified
aircraft................what a crazy idea.

On Fri, Jul 8, 2011 at 10:06 PM, E & T Andrews <etandrews(at)westnet.com.au> wrote:
Vans should consider including the
> flexible hose lines in the RV10 kit... has this been raised with Vans
> before?
>
> all the best
>
> Evan Andrews


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Kellym



Joined: 10 Jan 2006
Posts: 1705
Location: Sun Lakes AZ

PostPosted: Sat Jul 09, 2011 8:24 pm    Post subject: External Brake Lines - crack Reply with quote

You will find that the vast majority of Cleveland brakes are connected
via flex lines. Yes, there may be hard lines to somewhere nearby, but
the movement of the gear leg and the movement of the caliper is a flex
line. For example, the brake lines on my Mooney are flexible from the
center of the gear well down the gear leg to the wheel, all flex line.
While most fixed gear Cessnas had hard line down the gear leg, the
connection to the caliper usually was flex line if Cleveland or McCauley
brakes were used, because the caliper moves. With Goodyear brakes there
was hard line all the way, because the caliper was fixed and the disk
moved inside the wheel. Fuel lines are a combination. Most Cessnas (with
wing struts) have flex line between the wing and the fuselage. My
Mooney has flex line between the wing fuel pickup and the hard line to
the selector. Where there is movement or vibration, like in the engine
compartment, flex line is used. Where there are hard lines, they are
made of higher quality tubing on production equipment, not out of soft
line with hand tools. The only place I have seen tubing of similar low
quality is the oil drainback tubes on Lycoming engines.
I wouldn't call a C-17 a certified aircraft, because like most military
only aircraft, it isn't. They have very different missions and different
maintenance practices, not to mention vastly different pricing.
On 7/9/2011 8:56 PM, William Curtis wrote:
Quote:


Kelly,
I beg to differ but in certified aircraft that I am familiar, (Cessna)
flexible lines are used only where absolutely necessary. The
preference by certified aircraft designers is to use hard lines as
much as practicable if only so that there is no life limit on the
line.

This was driven home to me when I stood on the rear door of a C-17 and
looked up at all the hydraulic plumbing. With all those movable parts
and doors, NOT a single flexible line --not even at the actuators.
Where the line required movement, solid lines with mechanical (banjo
style) flexible fluid couplings were used. I took a picture of it but
I have to find it.

I know some Pipers use a short flexible line between their fuel tanks
and the fuselage fuel coupling. However on the Cardinal that; when in
doubt I ask "what would Cessna do" just as with Vans, flexible lines
are kept to a minimum and used only where absolutely necessary.

In the Cardinal fuel system, there are NO flexible lines. In the
Cardinal electro-hydraulic gear system there are only four short
flexible lines at the nose and main gear actuators. In the
retractable gear Cardinal, the brake line in the main gear is a solid
line. A the top of the RG brake line is a solid mechanical swivel
fitting and only on the lower portion by the wheel is a short easily
replaced flexible line used--remember this is a retractable gear
aircraft.

The point in all this is that hard lines ARE the standard in the
certified and military world in most areas and flexible lines are the
exception. Flexible lines are used only where hard lines are
impractical or expensive such as the movable mechanical (banjo type)
fluid connectors.

Just an alternative $0.02.

William
N237VX
On Jul 9, 2011, at 10:25, Kelly McMullen<apilot2(at)gmail.com> wrote:

>
>
> Van's would consider adding flex lines about the same time as they
> consider stocking the correct nose wheel. They won't change the nose
> wheel even though the correct one is exactly the same price. Flex
> lines could add over $100 to the cost, especially if you include flex
> lines in place of the crummy nylon lines in the cabin. Somehow we have
> been deluded into wanting durability similar to certified
> aircraft................what a crazy idea.
>
> On Fri, Jul 8, 2011 at 10:06 PM, E& T Andrews<etandrews(at)westnet.com.au> wrote:
> Vans should consider including the
>> flexible hose lines in the RV10 kit... has this been raised with Vans
>> before?
>>
>> all the best
>>
>> Evan Andrews



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A&P/IA, EAA Tech Counselor # 5286
KCHD
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PostPosted: Sat Jul 09, 2011 8:35 pm    Post subject: External Brake Lines - crack Reply with quote

I think the decision ..... flex or hard ..... probably boiled down to
weight and cost, and the hard lines win on both counts.
Hard line failures on certified aircraft happen..... but mostly with
many, many hours on them. I have no data, but I'd bet money on the RV
brake line failures on poor flaring technique, or cheap equipment.
Scoring the tubing with the flaring tool clamp is just asking for a
stress fracture. For me it's really difficult to get a flare I'm happy
with. I had to clean up my Rolo-Flair dies because of marks on the tubing.
Linn

On 7/9/2011 11:56 PM, William Curtis wrote:
Quote:


Kelly,
I beg to differ but in certified aircraft that I am familiar, (Cessna)
flexible lines are used only where absolutely necessary. The
preference by certified aircraft designers is to use hard lines as
much as practicable if only so that there is no life limit on the
line.

This was driven home to me when I stood on the rear door of a C-17 and
looked up at all the hydraulic plumbing. With all those movable parts
and doors, NOT a single flexible line --not even at the actuators.
Where the line required movement, solid lines with mechanical (banjo
style) flexible fluid couplings were used. I took a picture of it but
I have to find it.

I know some Pipers use a short flexible line between their fuel tanks
and the fuselage fuel coupling. However on the Cardinal that; when in
doubt I ask "what would Cessna do" just as with Vans, flexible lines
are kept to a minimum and used only where absolutely necessary.

In the Cardinal fuel system, there are NO flexible lines. In the
Cardinal electro-hydraulic gear system there are only four short
flexible lines at the nose and main gear actuators. In the
retractable gear Cardinal, the brake line in the main gear is a solid
line. A the top of the RG brake line is a solid mechanical swivel
fitting and only on the lower portion by the wheel is a short easily
replaced flexible line used--remember this is a retractable gear
aircraft.

The point in all this is that hard lines ARE the standard in the
certified and military world in most areas and flexible lines are the
exception. Flexible lines are used only where hard lines are
impractical or expensive such as the movable mechanical (banjo type)
fluid connectors.

Just an alternative $0.02.

William
N237VX
On Jul 9, 2011, at 10:25, Kelly McMullen<apilot2(at)gmail.com> wrote:

>
>
> Van's would consider adding flex lines about the same time as they
> consider stocking the correct nose wheel. They won't change the nose
> wheel even though the correct one is exactly the same price. Flex
> lines could add over $100 to the cost, especially if you include flex
> lines in place of the crummy nylon lines in the cabin. Somehow we have
> been deluded into wanting durability similar to certified
> aircraft................what a crazy idea.
>
> On Fri, Jul 8, 2011 at 10:06 PM, E& T Andrews<etandrews(at)westnet.com.au> wrote:
> Vans should consider including the
>> flexible hose lines in the RV10 kit... has this been raised with Vans
>> before?
>>
>> all the best
>>
>> Evan Andrews




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PostPosted: Sat Jul 09, 2011 8:53 pm    Post subject: External Brake Lines - crack Reply with quote

Kelly,
 
I think we are all in agreement that the 3003 versa tube is crap and 5052 would be much better.  Also, when I said NO flexible lines are used in the Cardinal fuel system, I meant from the firewall back.  Naturally, firewall forward is one place where flexible lines are standard.

William
-----------
 

On Sun, Jul 10, 2011 at 12:32 AM, Linn Walters <pitts_pilot(at)bellsouth.net (pitts_pilot(at)bellsouth.net)> wrote:
[quote]--> RV10-List message posted by: Linn Walters <pitts_pilot(at)bellsouth.net (pitts_pilot(at)bellsouth.net)>

I think the decision ..... flex or hard ..... probably boiled down to weight and cost, and the hard lines win on both counts.
Hard line failures on certified aircraft happen..... but mostly with many, many hours on them.  I have no data, but I'd bet money on the RV brake line failures on poor flaring technique, or cheap equipment.  Scoring the tubing with the flaring tool clamp is just asking for a stress fracture.  For me it's really difficult to get a flare I'm happy with.  I had to clean up my Rolo-Flair dies because of marks on the tubing.
Linn


On 7/9/2011 11:56 PM, William Curtis wrote:
Quote:
-->  RV10-List message posted by: William Curtis<wcurtis(at)nerv10.com (wcurtis(at)nerv10.com)>

Kelly,
I beg to differ but in certified aircraft that I am familiar, (Cessna)
flexible lines are used only where absolutely necessary. The
preference by certified aircraft designers is to use hard lines as
much as practicable if only so that there is no life limit on the
line.

This was driven home to me when I stood on the rear door of a C-17 and
looked up at all the hydraulic plumbing.  With all those movable parts
and doors, NOT a single flexible line --not even at the actuators.
Where the line required movement, solid lines with mechanical (banjo
style) flexible fluid couplings were used.  I took a picture of it but
I have to find it.

I know some Pipers use a short flexible line between their fuel tanks
and the fuselage fuel coupling.  However on the Cardinal that; when in
doubt I ask "what would Cessna do" just as with Vans, flexible lines
are kept to a minimum and used only where absolutely necessary.

In the Cardinal fuel system, there are NO flexible lines.  In the
Cardinal electro-hydraulic gear system there are only four short
flexible lines at the nose and main gear actuators.  In the
retractable gear Cardinal, the brake line in the main gear is a solid
line.  A the top of the RG brake line is a solid mechanical swivel
fitting and only on the lower portion by the wheel is a short easily
replaced flexible line used--remember this is a retractable gear
aircraft.

The point in all this is that hard lines ARE the standard in the
certified and military world in most areas and flexible lines are the
exception.  Flexible lines are used only where hard lines are
impractical or expensive such as the movable mechanical (banjo type)
fluid connectors.

Just an alternative $0.02.

William
N237VX
On Jul 9, 2011, at 10:25, Kelly McMullen<apilot2(at)gmail.com (apilot2(at)gmail.com)>  wrote:

Quote:
-->  RV10-List message posted by: Kelly McMullen<apilot2(at)gmail.com (apilot2(at)gmail.com)>

Van's would consider adding flex lines about the same time as they
consider stocking the correct nose wheel. They won't change the nose
wheel even though the correct one is exactly the same price. Flex
lines could add over $100 to the cost, especially if you include flex
lines in place of the crummy nylon lines in the cabin. Somehow we have
been deluded into wanting durability similar to certified
aircraft...............what a crazy idea.

On Fri, Jul 8, 2011 at 10:06 PM, E&  T Andrews<etandrews(at)westnet.com.au (etandrews(at)westnet.com.au)>  wrote:
  Vans should consider including the
Quote:
flexible hose lines in the RV10 kit... has this been raised with Vans
before?

all the best

Evan Andrews


[b]


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