Roto Flow fuel tank

[bigblueswope]

Ohio AV8TOR;17354 wrote: Thats why I use the Walbro felt clunks to help hold more fuel when it is not in the fuel. Might not be needed but I feel better. Also makes you wonder why we don't use bladder tanks.

After looking at that video, how do our engines not die after a long downline?

 

[Ohio AV8TOR]

stangflyer;17261 wrote: As I understand it, "G" force on downlines keeps your fuel at the back of the tank. That same force keeps our clunks back there also right? If it ain't broke, don't fix it.

Have you even flown full scale aerobatics or been in a plane doing a downline or hammerhead? Down lines are negative G's not positive. Gas in our tanks are more influenced by gravity than G's. G's just make the fuel weigh more and have more pressure in the position gravity puts it.

 

[Ohio AV8TOR]

bigblueswope;17358 wrote: After looking at that video, how do our engines not die after a long downline?

They are usually at idle or low throttle in a downline and there is enough fuel stored in the line. Do it from 5,000 feet and you will run out of fuel

 

[bigblueswope]

In the video, even the powered downlines didn't keep the fuel all the way to the clunk-end of the tank.

 

[Crashin' Keith]

jaybird;17221 wrote: Clunk stays in the back of most any tank. It should anyway.



The Rotoflow, seems like a good enough idea, but way to many moving parts to solve a problem that doesn't really exist with a conventional tank with a felt clunk. I have deadsticked a couple of my planes out of fuel with a felt clunk, and it gets every drop.

The clunk does not stay at the back of the tank during a down line. If it did it would be dry when all the fuel is at the front during a downline.

 

[bigblueswope]

Ohio AV8TOR;17366 wrote: They are usually at idle or low throttle in a downline and there is enough fuel stored in the line. Do it from 5,000 feet and you will run out of fuel

Makes sense. I guess the amount of air pulled in isn't enough typically to kill it. Tks.

 

[jaybird]

Crashin' Keith;17381 wrote: The clunk does not stay at the back of the tank during a down line. If it did it would be dry when all the fuel is at the front during a downline.

Ok. Whatever you say man.



I have been doing this for a while, assembled quite a few tanks, and on none of them does the clunk fall to the front when you point the nose down.

It does stay at the back, and yes it is dry for a short period of time.

 

[Ant]

I know for a fact my clunks all stay at the back of the tank, because I put a drinking straw over the fuel line to prevent it from going to the front. been doing that for 3 years and never had a problem and I fly hard.



In my opinion, you don't want the clunk line getting curled up, or what if it did go to the front and get hung up, then you go into a hover and bye bye engine.

 

[Flatspinjim]

Ant;17405 wrote: I know for a fact my clunks all stay at the back of the tank, because I put a drinking straw over the fuel line to prevent it from going to the front. been doing that for 3 years and never had a problem and I fly hard.



In my opinion, you don't want the clunk line getting curled up, or what if it did go to the front and get hung up, then you go into a hover and bye bye engine.

Same set up for me. I've never had a deadstick after a downline. I have seen clunks get balled up in the front of the tank and the results weren't good....

 

[Knife-Edge]

Pbilt024;17332 wrote: 32 will get you 10-11 minutes with reserve left over

Ah ok..thanks! A guy at our club is selling a new 40 oz roto flow since he's selling the plane he got it for. It already has a tank in it so I thought about buying it. But 32 oz seems to be giving enough time so will order that now.