What if...

[beeryboats]

I was reading the posts on the old style fuel tanks and the one about the owner who wanted an aircraft that could be LSA as needed for his daughter, and they got me thinking. What if you have a forced landing due to fuel contamination and do a bunch of damage, or worse. You knew the tanks could possibly come apart at some time due to autogas the former owner admitted to using. The Feds are going to say engine stoppage due to crap in the fuel, you tell them you sump everything every flight, and the insurance company checks out our forums about the tanks. Then what???

[Av8r_Sed]

You've identified a potential risk. You need to address the risk to ensure safety for flight. I wouldn't play what-ifs considering the FAA and what the insurance insurance company may think.

In the case with the fuel tanks, you would want to do a full inspection looking for any delamination, loose fibers or brown gunk that might migrate through the fuel system. This would include removing and inspecting finger strainers, filters and carb bowls. If it looks OK, then decide on an inspection schedule going forward to catch problems before they can impact your flight safety. You also have to figure out what fuels you have available and what you want to run going forward.

Also, if it was a new plane to me, I would definitely do a gravity fuel flow test to help ensure the fuel system can deliver in all phases of flight.

[HighWing]

In the case with the fuel tanks, you would want to do a full inspection looking for any delamination, loose fibers or brown gunk that might migrate through the fuel system. This would include removing and inspecting finger strainers, filters and carb bowls.

The above is good advice. This is one reason I was a bit amazed when I saw the mid tank porting system on the newer style tanks. Being able to remove the finger strainers at each annual inspection is a must do, in my opinion. And at least with the Series V I helped with, that required a builder modification. I would much prefer the risk of fuel starvation on a long decent - especially with a low fuel indicator system installed - than the risk of a serious tank issue I was unable to discover with a finger strainer check. The most I ever found was a chunk of rubber that obviously came from a recently maintained airport Card Lock pump. All home fueling was with a Mr Funnel with its internal screen.

Another thought on the tanks. These are hand made one at a time. A single incidence of a baffle delamination does not necessarily condemn all the Denney, Skystar and Kitfox Aircraft tanks. There is simply too much history to think that this is a common problem. Remember the old time car buying advice - never buy a car assembled on Monday or Friday? With the fiberglass tanks, you have a guy putting them together - How is is his day going? You have a mix of resin - are the proportions right and where is the mix regarding its pot life? Have the tank halves sat over the long Thanksgiving weekend?

I had 9 years on my first tank with 900 hour of fuel - mostly mogas pass through them. There are three Model IVs on the airport here, two with 1500 hours. Lots of flights side by side with a dozen or more guys and heard all the hangar talk. The Kitfox forums have been online since their inception in 1994 and I don't remember this issue being ever mentioned until recently with the photos of the delaminated baffles. The big issue was the Kreem, but in my opinion, that was overblown as well as again there is just too much history with too few significant issues reported over the years. My guess is that the Kitfox fleet is nearing 5000 airplanes now. There will always be problems that surface, but a good dose of perspective is needed in the mix as well. All three of the Kitfox companies have been very forthright in their Service Letter program. This is where you will find the trends as they are based on multiple incidences.

And finally I Have been through a crash that destroyed the airplane. The tanks held up fine. My annual check list showed the finger strainers removed and the tanks inspected and the fuel filters maintained - not a problem.

5955

We didn't walk away, but just rolled out.
5956

[Esser]

What was the cause of your crash?

[HighWing]

Depends.

What initiated the attempt at an emergenc landing was an oil pressure drop to zero.

The official FAA determination was a foreign material in the oil tank that impeded oil flow. The engine never quit running. The foreign material was most likely a lid from an oil bottle that was somehow introduced during an oil change - by me.

The Crash? It is intersting in retrospect. We were in the foothills of the Sierras in rolling hills mostly wooded with clearings. I picked the one I wanted and heard my wife ask, "Do you see the power lines?" Yes. Then I proceeded over the power lines to my intended touch point. What I later found after driving back to the location is that I chose, unwittingly, to land down hill. The ground was dropping as fast as I was decending and I was running out of clearing To avoid the oak trees at the edge of the clearing I stalled it and planted it. I have done a lot of off airport landings and feel that if I had recognized the slope and adjusted my approach accordingly, I would likely be still flying the original Model IV.

What have I done?

1. I have a back up oil pressure reference. It was a year before the FAA called me and we discussed what they found. Until that time, I didn't know if it was a faulty gauge or a real oil pressure issue.

2. I no longer remove the top of the oil tank during an oil change. We Rotax owners are the only people on the face of the earth who do. All the others have no ill effects for not doing it. None of the Lycomings, Continentals, Franklins, Jabirus or the billion cars reported on the road today wipe out their oil sumps.

3. In selecting an emergency landing site, I would carefully evaluate for slope. In my case, I was south of a River and landing toward the south expecting rising terrain. I was unaware that I had crossed a crest and was in a different watershed.

[Esser]

Glad you are still here. That is quite the wreckage. How high do you figure you were when you stalled?

[beeryboats]

My wife asked me how many of the old tanks were made and how many issues there have been. I had no answer for her. Any idea how many have had tank problems?

[HighWing]

Josh, I don't really knolw. Probably between ten and 20 feet.

[mr bill]

Looking at the wreckage, you are lucky to be alive.