Todd I am new at turbines but you are saying the exact opposite of the jet cat install manual for placement of the fuel shut off. They show the shut off after the pump and the ball valve after that.
http://www.jetcatusa.com/PDFFiles/In...l%20V6.0J2.pdf

Yes, and that same diagram was in my P-80 manual back in 2001 .... From a safety stand point, locating it before the pump has proven to be prudent deviation.

thinking back those old JetCat manuals, for many of us they were the definitive guide on a Jet installation. I do agree however, agree its safer to place the valve on the suction side ... this conversation can go on for pages about valve placement as it has in the past, lol ... if anything, at least there is atenion being drawn to safety. Whats actually worse is complete lack of understanding or complacency.

Another proper install how-to that comes to mind, which can be critical actually ! is to properly orient your fuel filters ! most if not all are directional and intended for fuel flow only in one direction. Running fuel in reverse through some filters will allow air bubbles to accumulate and sporadically be released in larger quantities .... flame out ..


its also a good idea to secure/mount fuel filters vertically with "upward" fuel flow through them. This allows easy passage of any bubbles that make it into the system to pass through without accumulating. When i start up i usually shake the side of the fuse, or the filter directly and many times i see this dislodge bubbles thorough the plumbing on start. If fueling through most antibubble tanks, there is still air that often makes its way into the fuel pump draw side ..



Voy

I don't understand how somebody hasn't come with the idea of making a video with a step by step buildup of a jet. There's a lot of us out there that could benefit of this kind of information and learn from the masters. For some people, servo installations, linkage, powerboxes, programming, etc could bee seen as an easy thing, but for sure for several people is not.

In other hobbies (like plastic model airplanes), there's plenty of videos available that will guide through the complete buildup and painting process. Those videos are very popular and sell very well. The important thing is that it allows somebody that is completely new to the hobby to come up with a nice decent model without having experience at all.

We are always talking about safety and a good assembly video could be a good way of making sure that people are aware of how things need to be done in order to prevent accidents.

Somebody wants to pick up the ball ?

I would be purchaser NÂş 1.

I know!!! Love to see under it to see how neat it is looking!! I try and try, even used snake skin to hide all of the wires, air hoses, etc, and covered it all with carbon fiber, and mine is still a mess!

Dave Platt has jet videos available. I have never viewed them but they may be an option.

Beautiful install Kasper! Very creative layout! That Carbon would concern me just knowing it could create an issue

I notice "Former" in the description, has it been lost?

Years ago, RCU was peculating with all sorts of brilliant educational, informative, instructional build, technical and install information. It is really sad to see RCU's forum go from "the learning channel" to "Jerry Springer" in just a few years [:@] The "rookies" are the ones that suffer [] The info is still here, somewhere.... Unfortunately, RCU search engines make finding those threads all but impossible.

build thread: http://www.rcuniverse.com/forum/m_10...m.htm#10853367

yes. i made a landing i wassent sattisfied with, i took the desision to go again and make a better, but i forgot how short the grassfield was, i never made it, i ran down into a ditch in the end. and the fiberglass was dead. i wanted to make a new with just the fiberglass piece from skymaster, but they wanted 2600$ for bare fiberglass. so i sold the gear.

I tend to agree on placing the shut-off on the suction side of the pump but be careful about restrictions.

Its not a good idea to 'add' restrictions on the suction side, free flowing fuel is the key so the pump can run with stable rpm's at any given turbine rpm, those Festo gate valves are very good but the restriction inside them in terms of the narrowing down of the bore is quite big and this will add restriction to flow and in some installations it might add to problems too.

marcs

Hi Marc,
Great points! Although the SMC and Festo 6mm ball valves have adequate flow rates for our applications. Restrictions on the suction side can be a common problem, especially on 160+ class engines. Most restriction induced issues I have seen are sourced at the tank/air trap using inappropriate tubing/fitting sizes including tank bung, clunks and vents. We have used Festo and SMC 6mm ball valves inline on the AMT Titan engines, consuming 40oz/min WOT without any fuel restriction issues. Of course, the GBR Jet composite air traps do help with flow restriction!!

I completely agree, the filter should be mounted vertical with one additional piece of advice; don't actually "Mount" the filter! leave the body of the filter itself free to move around a bit, securing the fuel lines in/out. This allows the filter to move around a bit during flight to assist the release of smaller bubbles. If mounted solid, the filter (especially the Jetcat supplied one) tend to hold the small ones till the bubble gets large enough to break surface tension.

Kasper, sorry to see this plane has been lost []

I put shut off valve after the pump.
Never know you can suck air in from the low pressure side.
Even Festo or other the shut off valve been very reliable.
But for peace of mind limit air suck in put shut off valve on high pressure size.

Hi Todd. Great thread, (and a good diversion from FEJ woes).

I personally have not experienced a confirmed static discharge problem, BUT, have had a receiver issue that might have been static related. I would be very interested in any practical advice on how to avoid it.

You suggest we should try to avoid crossing of wires and fuel tubing, or keep a few inches separation.

I think that this would be impossible on all but the biggest jets. (You would need a cavernous fuselage.) Certainly impossible with a Bandit or Flash. And it is obvious that most of the “Nice” installs in this and the other thread have fuel lines and tanks/UATs right next to Rxs, ECUs and their associated wiring. These jets obviously do no suffer from it.. Static discharge seems to be almost a randomly arising issue!!

My Bandit install below..

And FWIW, I put the shut off valve after the pump..


A

Truly sorry Kasper...

You should have kept it. Great frame/flyer

I crashed my F4 a couple of years and kept the gear. I am about to receive another frame

Because of static, I used to route an electric wire thru the train, pipe and turbine. Once in a while route another one to the ground. I don't do it any more. Never had a problem with turbines till 160N and got lazy...

Regards

Great thread Todd! And brings back memories of "learning" all these do's & don't(s).

Regarding the shut-off location, that's a debate that will forever last as long as we use shut-off valves. Unless you have actually experience a runaway ECU, it's mostly academic for most; and is so rare, most never see it and the potential danger.

The one thing I like to do in regards to fuel system installs, is to run 6mm festo tubing as far as I can to the turbine before reducing to 4mm. I used to run 6mm to the pump, then 4mm out to the engine, but then changed it to obtain the least restrictive fuel system possible. It's very simple to stick a piece of 4mm tubing on the pump outlet (IF it has a small barb) then slide the 6mm tubing over it and safety wire, then run as far as possible.

Well, got run and get my canoe so I can make it from the trailer to the flight line at Mississippi Afterburner!

NEED NEW DESIGN SHUT OFF VALVE,, RETURN LINE BACK TO SUCKTION SIDE OR TANK..????????????

Todd, I don't really seem to understand this phenomenon, would you please be so professional to personally demonstrate it on youtube?

Hi Todd
A couple of years ago when carbon fibre was comming into favor I wraped a receiver and 3 sat's in carbon fibre and took it about 130-150 mts out the front of my house and never had a problem with reception, I have been useing C/F trays ever since whith no probs on my logger's . just my obervation....
Cheers
Mav

Attached is the Festo spec sheet for the 6mm Festo Ball valve. The valve is rated at 10 bar (145 psia) of positive pressure and 1 bar (14.5 psia) of vacuum pressure. So, when the valve is placed on the suction side of a fuel pump then its only good to 1 bar of suction pressure. Having seen how a P180 or P200 sucks in the sides of a BVM UAT, I would think that it is pulling more than a 1 bar vacuum.

We lost a jet at Miss Afterburner this weekend due to a flameout. We found the CAT empty and all fuel lines/connections full of fuel and secure, EXCEPT, the fill line which was dry. The guy had installed a 6mm Festo valve in the fill line. We concluded the P-200 had sucked air through the Festo fitting. I can't say for sure that the fill line was securely pushed into the fitting but it was cut squarely.

I've used Festo's on the suction side myself without problems but after this incident, I'm not so sure.

Craig

14.5 psia is about one atmosphere. At sea level that's about the maxim pressure you can generate pulling a vacuum, no matter how hard you suck, no matter how powerful the pump. It's about 33 feet of water column. That being said it is easily enough pressure to crush just about any thin wall fuell cell.

I think you could safely get away with putting that little ball valve anywhere you would like after the UAT. I DO think a poorly cut tube in a festo fitting is more likely to leak under vacuum than under pressure. And most certainly if someone mistakenly uses Tygon tubing in a Festo fitting. Notably if the fitting leaks under pressure you will have liquid fuel leaking out. Under vacuum, a silent killer

Happy Flying,
Steve
<br type="_moz" />

Thanks Steve and Craig. You have just resolved the whole “Festo on the suction side” issue for me..

I did a bit of research and discovered that Steve is quite correct. The MAXIMUM vacuum any pump can possibly create is 1 Bar, or one atmosphere. (Stands to reason really as one atmosphere the maximum outside pressure we will ever see, unless we go flying in a pressure chamber.)

If the Festo spec sheet is correct, these fittings will hold any negative pressure that can be applied by any pump. I will continue to use them on the suction side of my fuel system, with the proviso that the correct tube type is used, and it is cut correctly.

Thanks guys.

Some of my installs, beware, those that look nice on the top, are a mess below deck (more or less)

My Geek Brotherin' have heeded your request Barry .. http://www.youtube.com/watch?v=7m-ooPjGsQo

Hi Craig,
Steve is absolutely correct, you should never see beyond 1 Bar negative. Suction above 1 bar would also "boil" the fuel and you would be sucking air anyway! The Ball valve has the same negative pressure rating as the tubing. Most likely, the tubing walls would begin to collapse before the festo quickstar fitting seal would leak in vacuum.
Todd

Anything wrong have it on high pressure side.
I feel safer not have air suck in. Any prevention from leak is better than a chance of leak can happen.