Fuel Line Routing

For general discussion of the Just Aircraft family of aircraft.
Includes: Highlander, Escapade, Summit and SuperSTOL.
Post Reply
jjacky
Veteran Member
Posts: 239
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Fuel Line Routing

Post by jjacky »

Woke up last night worrying about how I routed the fuel lines on the Highlander. The worry is... if a slug of water gets in a dip in the fuel line will the hydro-static pressure of the fuel shove it to the gascolator. I routed my fuel lines under the floor and seats. Now I'm thinking running them down the rudder cable fair-leads would be a better solution...what did you all do?
Plan not to be the first at the scene of the accident!
User avatar
Tralika
Veteran Member
Posts: 385
Joined: Thu Oct 08, 2009 12:49 pm
Location: Wasilla Alaska

Re: Fuel Line Routing

Post by Tralika »

Along the bottom stringer under the seats.
John Nealon
Wasilla, Alaska
Highlander Extreme #191
mykitlog.com/jnealon
User avatar
BucF16
Veteran Member
Posts: 463
Joined: Sun Mar 23, 2014 11:47 am
Location: Alexandria, Ohio

Re: Fuel Line Routing

Post by BucF16 »

same
Bruce Johnson Highlander # 393
"Because I fly, I envy no man on Earth"
Builder web site:
http://www.bruceshighlander.blogspot.com
User avatar
SheepdogRD
Proprietor
Posts: 930
Joined: Tue Nov 30, 2010 5:41 pm
Location: West of Atlanta, GA

Re: Fuel Line Routing

Post by SheepdogRD »

Tralika wrote:Along the bottom stringer under the seats.
Same here.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
User avatar
alan
Veteran Member
Posts: 398
Joined: Fri Feb 04, 2005 1:39 am
Location: Baytown, TX

Re: Fuel Line Routing

Post by alan »

Ditto.
If I had known I would live this long I would have taken better care of myself.
jjacky
Veteran Member
Posts: 239
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Re: Fuel Line Routing

Post by jjacky »

Fantastic, now I can sleep again. Just a caveat, a friend of mine (a fuel systems engineer) warned me to watch out for freezing temps
and frozen water slugs but, if you're conscientious about your fuel management, this should not be a problem.
Thanks All!
Plan not to be the first at the scene of the accident!
FredHoffman
Veteran Member
Posts: 136
Joined: Fri Mar 23, 2012 8:57 pm

Re: Fuel Line Routing

Post by FredHoffman »

I made sure the lines ran in a descent (in 3 point attitude ) from the tank to a sump drain under my seat and from there in an ascent to firewall. If the fuel lines go lower than your header tank sump drain water can collect in that fuel line which is now the lowest point. Ethanol fuel can suspend a significant amount of water and can precipitate out as the temperature changes. It could collect in that lower line and stay there until say something like a very nose low high power setting while (buzzing your friends) sucks the water into the engine !
User avatar
SheepdogRD
Proprietor
Posts: 930
Joined: Tue Nov 30, 2010 5:41 pm
Location: West of Atlanta, GA

Re: Fuel Line Routing

Post by SheepdogRD »

FredHoffman wrote:I made sure the lines ran in a descent (in 3 point attitude ) from the tank to a sump drain under my seat and from there in an ascent to firewall. If the fuel lines go lower than your header tank sump drain water can collect in that fuel line which is now the lowest point. Ethanol fuel can suspend a significant amount of water and can precipitate out as the temperature changes. It could collect in that lower line and stay there until say something like a very nose low high power setting while (buzzing your friends) sucks the water into the engine !
A couple of years ago, I was at the Plane Fun Fly-In in Brasstown, NC (https://www.planefunaircraft.com). Co-host Vic Payne pointed out the same thing: that the header tank is not the lowest point in the fuel system. In testing, they used clear fuel lines in the cockpit, and they saw water collect in the line between the header and the fuel valve.

Vic showed me a Highlander with a fuel system that resolves that problem, and I took some pictures. This system has the fuel line from the header angling down along the fuselage side panel to the fuselage tube that crosses behind the seats.
1.jpg
It turns toward the center of the aircraft to the inboard right seat rail...
2.jpg
...and then turns forward to a gascolator mounted on the seat rail. This is the low point of the system.
3.jpg
Then the line angles up to the fuel valve. From the valve, it angles up across the right side of the control tunnel.
4.jpg
At the forward doorpost, it goes up along the angled tube in the cowl side panel, and then to the engine.
5.jpg
Vic said the advantage to the system is that the gascolator is at the lowest point in the system in both tail down and tail up configurations, so water that gets past the header tank naturally goes to the gascolator.

When I learned about this, my system was already plumbed below the floor in aluminum tubing, and my inside panels were covered. I filed the information in notes for the next build.
You do not have the required permissions to view the files attached to this post.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
jjacky
Veteran Member
Posts: 239
Joined: Wed Aug 19, 2009 12:07 pm
Location: Greensboro, NC

Re: Fuel Line Routing

Post by jjacky »

Guys thanks a-bunch for the info and great pictures. My fabric person is hot to trot so I'm not going to redo the whole fuel system but, like you Dog, I'll keep this on file for the next build and I'm going to install a couple of sumps per yer suggestion Fred. Now I just gotta find a couple of simple sumps.
Plan not to be the first at the scene of the accident!
FredHoffman
Veteran Member
Posts: 136
Joined: Fri Mar 23, 2012 8:57 pm

Re: Fuel Line Routing

Post by FredHoffman »

User avatar
danerazz
Veteran Member
Posts: 1240
Joined: Tue Aug 18, 2009 9:33 pm
Location: Bangor

Re: Fuel Line Routing

Post by danerazz »

My biggest takeaway here is your seatbelts are attached to the rails.
Dane

Paralysis by analysis
#242
User avatar
SheepdogRD
Proprietor
Posts: 930
Joined: Tue Nov 30, 2010 5:41 pm
Location: West of Atlanta, GA

Re: Fuel Line Routing

Post by SheepdogRD »

danerazz wrote:My biggest takeaway here is your seatbelts are attached to the rails.
Interesting observation. Let's append that discussion to the Lap Belt Attach Points thread you started http://www.wingsforum.com/viewtopic.php?f=218&t=23964. I'll put a transition post there.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
User avatar
CanadianSheepHunter
Veteran Member
Posts: 678
Joined: Thu Feb 26, 2015 1:05 pm

Re: Fuel Line Routing

Post by CanadianSheepHunter »

SheepdogRD wrote:
FredHoffman wrote:I made sure the lines ran in a descent (in 3 point attitude ) from the tank to a sump drain under my seat and from there in an ascent to firewall. If the fuel lines go lower than your header tank sump drain water can collect in that fuel line which is now the lowest point. Ethanol fuel can suspend a significant amount of water and can precipitate out as the temperature changes. It could collect in that lower line and stay there until say something like a very nose low high power setting while (buzzing your friends) sucks the water into the engine !
A couple of years ago, I was at the Plane Fun Fly-In in Brasstown, NC (https://www.planefunaircraft.com). Co-host Vic Payne pointed out the same thing: that the header tank is not the lowest point in the fuel system. In testing, they used clear fuel lines in the cockpit, and they saw water collect in the line between the header and the fuel valve.

Vic showed me a Highlander with a fuel system that resolves that problem, and I took some pictures. This system has the fuel line from the header angling down along the fuselage side panel to the fuselage tube that crosses behind the seats.
1.jpg
It turns toward the center of the aircraft to the inboard right seat rail...
2.jpg
...and then turns forward to a gascolator mounted on the seat rail. This is the low point of the system.
3.jpg
Then the line angles up to the fuel valve. From the valve, it angles up across the right side of the control tunnel.
4.jpg
At the forward doorpost, it goes up along the angled tube in the cowl side panel, and then to the engine.
5.jpg
Vic said the advantage to the system is that the gascolator is at the lowest point in the system in both tail down and tail up configurations, so water that gets past the header tank naturally goes to the gascolator.

When I learned about this, my system was already plumbed below the floor in aluminum tubing, and my inside panels were covered. I filed the information in notes for the next build.
Is there any disadvantage to this?...Im currently planning my fuel system and have an Andair gascolator ordered and love the pics of this install. The lines coming off the top of the header tank...is there one to the forward port of wing tank and one to rear port of wing tank? Is there a vent line from header tank to one wing in these pics?

thx
User avatar
SheepdogRD
Proprietor
Posts: 930
Joined: Tue Nov 30, 2010 5:41 pm
Location: West of Atlanta, GA

Re: Fuel Line Routing

Post by SheepdogRD »

CanadianSheepHunter wrote:Is there any disadvantage to this?
I couldn't see any problem with it. I didn't follow the design because mine was plumbed already. But I sure put it on the list for my next one.
CanadianSheepHunter wrote:The lines coming off the top of the header tank...is there one to the forward port of wing tank and one to rear port of wing tank?
I don't remember whether both ports were plumbed on those wing tanks. I didn't plumb my forward ports.
CanadianSheepHunter wrote:Is there a vent line from header tank to one wing in these pics?
I don't remember the vent configuration. I used two header tanks, and vented from each header to the wing tank that feeds it.

If you plan to follow Vic's routing, it might be a good idea to contact him at Plane Fun Aircraft (http://www.planefunaircraft.com) and ask if he has any further recommendations.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
User avatar
CanadianSheepHunter
Veteran Member
Posts: 678
Joined: Thu Feb 26, 2015 1:05 pm

Re: Fuel Line Routing

Post by CanadianSheepHunter »

Thanks
Post Reply

Return to “Just Aircraft”