stevekott

OK, yes I did it! I fueld my plane with the fuel shut-off valve open yesterday. I admit it so don't give me a lot of safety lectures.

But on a handful of occasions I've gone through start-up forgetting to open it and had the embarrasing dead start. So I'm working on my attention deficit disorder (I've had it all my life) which might explain why I left it open.

And there is a fuel shut-off solenoid that shuts the fuel off anyway, right?

So two successful flights, fueled up for the third .. initiated the start. Everything seemed fine then .. 24" long yellow flame out the back coughed itself out .. Then the paint on the fuse started to get darker .. and darker .. Panic, I mean preparedness, set in and simultaneously shut down the turbine and pumped 2-1/2lbs of Halatron into the inlet.

A few melted wires, some burned panels, probably 5 or 6 nights of repair work.

I won't mention the brand of turbine as I don't thnk that would be fair. They all have solenoid valves and they are all similar. And it's being checked out now and I don't want to state what is not confirmed.

My point of this post is to possibly keep someone else from going through what I went through.

Yes there is something wrong with the turbine/valve/fuel system, it needs to be fixed. It most likely won't happen to you but, I put more faith in those solenoid valves/fuel system than I should have. And I'm sure many guys are fueling with that little valve conveniently left open depending on the dependable little solenoid/fuel valves.

My point is that IF I had closed the fuel shut-off, even with a defective turbine/valve, I would most likely not have had the FIRE I had.

Just a helpful hint to pass along.

Flame On! Happy Flying!
Steve

Eddie P

My Feedback: (4)

You most certainly also want to replace the exhaust pipe - an over heated pipe.. well it's been beaten to death here on the forums so yes replace it (unless it's a Boomerang with no pipe!). Check the bulkheads and airframe for heat related structural damage - the paint getting dark tells me you had some serious heat on the airframe structure!

Good job aborting the start before it got worse. It always gets worse on a torching start!! Best to quit while one is ahead of the pile of flaming debris and you did that, saving the airframe so good work on that in the "heat" of the moment.

I did the same thing you did once on my Reaction 54 - after about 30 flights I got careless and fortunately the only damage was to my removable home made, Home Depot stove pipe starting pipe.

David Searles

My Feedback: (49)

Steve,

Experience is always the best teacher! I made the exact same mistake on my second jet, but I compounded the mistake by not having a fire extinguisher at hand! Total loss! Your lesson was less costly than mine, for sure!

A great reminder.

David S

stevekott

That Darn Experience Teacher! Yes, I usually learn from my mistakes. Indirectly I learned from this guys:

www.youtube.com/watch

His plane burns down to the grass WHEN THERE IS A FIRE EXTINGUISHER RIGHT NEXT TO HIM sitting under the table!

I got caught in a fire when I was 22 and I never forgot that experience, things happen VERY fast.

A few fun facts: I had about 25 successful flights on this install. The filter was inline AFTER the fuel pump. If there was some crud in the line I don't know where it could have come from. After the fire there was about a 2' x 2' kerosene stain on the ground under the jet. Had I not had the extinguisher I think I would have looked like the video

Nhalyn

That's the best teacher you will not forgot...

For the vid', I think the extinguisher is :
A/ his extingisher but empty after servicing on this plane (probabely not the good answer, should not have been under the table, but we don't have the start and first minuts actions)
B/ not a CO2 extinguisher
C/ not his extinguisher and he don't want to use it... (strange...)
D/ panic mode !


The valves that are used for fuel control are not designed to support the high pressures endured when we are fuelling our tanks (4 to 5 liters in few minuts, far less that it will take to empty the tank in flight). A mechanical valve can endure that.

Keep cool when doing pre-check (close valve, fuel up, air up, battery charged), pre flight check (valve open, Tx-Rx on and checked, all working), and also a post flight check (close valve, close Rx-Tx, eye in the plane and all OK)

When I fly my jet, people around me knows that during my check I will not answer questions or joking around... I'm still waiting for THE mistake, I know it will come one day or another. Thanks to help us to remember this can arrive. Hope your jet will fly again ASAP.

madmodelman

Steve, I have to admit I sometimes forget to turn the tap off after a flight and refueling for the next one.
I won't do it again! Thanks for the heads up.

shepp

I once heard that a smart man learns from his mistakes, but a wise man learns from others mistakes. I will try to be wise here. lol. Thanks for the heads up on something we all know but seem to forget.

Shep

The problem with " Experience" is the test comes first and then the lesson.

DiscoWings

My Feedback: (76)

I thought most auto kero start turbines will leave the solenoids closed by default as a fail safe to prevent exactly what you are describing.

Eddie P

My Feedback: (4)

Solenoids can sometimes leak just enough to flood the engine during a re fueling - with the pressure of the re fueling acting through the tanks, UAT, fuel pump and into the delivery lines. Not enough kerosene passes by to keep an engine running with the solenoid closed, so the solenoid is indeed an engine stopper in itself even with the fuel pump running. But enough can pass through and pool in the engine during a 3 minute re fuel under just the pressure of the re fueling pump putting fuel in the tanks. Then we "might" be left with enough fuel to torch during start if we are unlucky enough. Kero start or propane start it's the same mechanism of fuel potentially slowly leaking by the solenoid for those few minutes of re fuel without the shut off valve. So shutting off the valve is a good idea. The AMA requires the manual shutoff valve as a safety measure for alternate engine manual shut down - but over time it's become best practice to use it during re-fuels. Some installations internationally don't call for a separate shut off valve. The solenoid alone will often work just fine but sometimes is doesn't as we see!

Boomerang1

Don't forget to open it either!

That was my first visit to flame city, start running fine on gas but no transition to kero.
I noticed the fuel valve off & not thinking I opened it up, of course, by then, the pump
was running at maximum speed & you can guess the rest.

My advice would be if the start has anything out of the ordinary abort the start & recheck
everything. - John.

DiscoWings

My Feedback: (76)

Not so sure about this... I hooked up a MAIN FUEL line solenoid backwards on the ECU once, pump voltage shot up to 6.55 volts but not a drop of fuel went through, at 6.55 volts that pump is close to 50 PSI.

This was with a JC p-240 on the first run.

DAN AVILLA

My Feedback: (12)

I think it is all related to the reason you should clean your jet cat fuel filter at least once a month. I do it about every 15 to 20 flights or if the jet has been sitting. I have noticed in the last 2 years that the fuel filters get a varnish looking substance on them. I run kero with a good oil and anti static. Many times when I inspect the filter it has a shine on it. It turns dull when cleaned. When you remove the filter I have a had time blowing through it with my mouth. I use brake clean on it and blow it off. Now it is easy to blow through it. I think that the fuel valves are getting gumed up and not closeing . We have all made the mistake of not shuting them off. Many times I go to events and a fellow jet buddy is having engin problems. 99 percent of the time I show them how to clean the filter and it fixs their problem. I have had flame outs because of this. Clean the filter and it is gone. Buddys have asked me about pump pressure. I have never seen it go up when the filters are restrictive. Dan Avilla

GSR

My Feedback: (145)

You also need to close it at other times. I left it open on my BVM Mig, turned the fuse upside down to work on it for a while. When I turned it back over on its wheels and started it had a big hotstart. As I had my fire extinguisher right there if was very lucky, it only cost me a pipe and a bypass. When it was upside down the tanks were higher than the engine and siphoned fuel into the engine. Just get in the habit of turning off the cock when you turn off the airplane. EVERY time. Scotty

Eddie P

My Feedback: (4)

GREAT point Dan. Do you use Festo fittings to make the removal of the whole filter assembly easier? Or do you just pull the lines off the filter and take the element out to clean? I very much dislike opening my fuel system up as it's messy and I am very cautious about getting fuel and oil mix on my skin as it's nasty stuff - latex gloves and rag time. Plus I'm always afraid I'll introduce contaminants every time I open up the system. I have to admit I don't mess with my filters nearly that much - usually only after installing a new fuel pump but I do check pump voltages and have relied on this in the past as a problem spotter. Interesting on your note about voltages and other restrictions though. You fly so much though Dan, you are clearly doing it right.. I'll have to consider your experience here as a reason to change my own routine a bit.

It sounds like there is a potential sludge problem that might not be visually seen when looking at the filter element while wet with fuel? I wonder if the anti static stuff is causing the varnish. I haven't used it before until this season, I will be on the look out. What brand brake cleaner do you use - is it a spray?

AFTERBURNER1

My Feedback: (80)

I remember that day..

[]

essyou35

My Feedback: (11)

I think your fueler is too high. pressure. If its a jersey pump, goto radio shack and get some10ohm 10amp resisters and put two in series. The uat and fuel lines should be able to allow all the fuel to flow into the tanks, you pressure is so high it is going through a much smaller line after the fuel pump and spinning the pump as well.

Just a thought, I fly a flyeagle so take my advice for whats its worth.

stevekott

A lot of great input, it's nice to see photos of modelers EXCITEDand enjoying their hobby in spite of af a few set backs.

I first need to say that the service I received from the Turbine manufacturer was outstanding. I dropped the motor off with the sales rep at 11:00am and picked it up from the Tech at 8:30PM the same day.

They had completely gone through the motor and tested it and determined the cause of the problem. ........ A little piece of crud in the starter solenoid valve.

stevekott

The piece of crud was flexible in nature like a cured RTV or polyurethane glue. It had obviously been in the fuel system AFTER the filter from the initial time of the install. It took 25 flights to manifest itself as a problem.

Where did it come from? When I installed this turbine I remember putting a new length of fuel tubing and purging out the air, but not wanting to make a mess, I did not let the fuel run for a while into a waste container prior to hooking it up to the motor. NEXT time I will do that.

Another possibility is that it was there from the manufacturer as a sealant residue. The factory could not rule that out and covered ALL of the service under warranty. I think they would have covered some of the consequential damages also. I didn't push for that as I could not rule out the possibility that the crud was mine to begin with. Also had I closed the shut-off valve during fueling it would have greatly reduced the damage. (I think)

I did an experiment where I took a length of 4mm fuel tubing, rubbed on it a little with a cloth to put a typical static charge on it. Low and behold it worked like a little vacuum cleaner as I passed it over some of the crud on my workbench. It is possible that the crud got into the new piece of tubing AFTER the filter and I didn't notice it. Again I would suggest on a new install to flush out the fuel system into a waste container BEFORE connecting it to the turbine.

madmodelman

Good news!

stevekott

Shutting the manual Fuel Valve while fueling is a prophylactic (like that word?).

If the solenoid valves are free of crud and working correctly they will prevent flooding of the turbine like I had. This morning I took a spare valve, and put pressure on it at 100 psi. It functioned fine, turning on and off! Even at that pressure.! So even if that manual valve is inadvertently left open no fuel should have flowed into the turbine during fueling even with the strongest of fueling pumps. I think the fuel cells would rupture first. That said .. with the remote chance of a failed solenoid valve it's cheap insurance to prevent significant fire damage to close the manual valve.

A word of caution: If you are seeing fuel going into the turbine rotating the plane like Scotty mentions above you most likely have a defective or impaired solenoid valve.

A way to test this would be to unplug the electrical connection for the start-solenoid and the fuel-solenoid and then run the Fuel system purge. If ANY fuel is observed flowing into the turbine the shut off valves are probably not working correctly.

Another observation, on a few occasions I did notice an 18" yellow flame during a few start ups. It quickly coughed itself out with a little white smoke and the start proceeded normally. If you have rough 'noisy' start that is unusual, maybe a little extra flame or smoke, it might be a good indication to do a valve test.

Happy Flying!
Steve

DAN AVILLA

My Feedback: (12)

Eddie P

My Feedback: (4)

Dan thanks for the thoughts. We just started using Anti Static Stuff up here in high country after one of our guys had a series of flame outs, fortunately after landing each time. The Jetcat "watchdog" message was shown as the reason for the engine stopping. Some anti static spray and anti static fuel additive have both been used, and no more "watchdog" flame outs due to static electricity. Good idea about the filters though.

sideshow

My Feedback: (11)

Nice pipe Scotty!

essyou35

My Feedback: (11)

Ive never thought that much damage from a hot start could be possible. The turbine looked like a grilled steak. That crud looks like melted fuel tubing..
I've left mine closed before. I've left it open too. I have reduced the current to my fuel pump with resistors which really helps keep the fuel in the tanks even if the solenoid is open. Those fuelers will certainly put some serious pressure on the fuel system that isnt necessary. A couple more minutes wait is well worth it.

PS just a tip, make a check list for startup (including fueling) and shut down. I have lists like that for what I need to bring out to the field.

CARS II

My Feedback: (7)

A lot of good info here.

In the very beginning of my turbine adventure I starting using a few check lists, I Have ( like essyou35 mention ) a check list for before leaving home, one for before starting and one for after shutting down.

Once may moons ago I forgot my transmitter at home and went back for it, a one hour round trip, from then on I starting using the before leaving home check list, it has been over 25 years since then and I have not once left my transmitter or any other important item at home again.

During shutdown I religiously make sure I close the manual shut off valve ( then I confirm is close with my check list ) during refueling I don't even think about fuel been pumped into the engine.

As a CD is one of the items I strongly emphasize ( together with the fire extinguisher ) during a qualification flight.