Building a Nieuport 11...

[Frank Giger]

Hey, I'm part of the governmental records!

https://app.ntsb.gov/pdfgenerator/Re...=HTML&IType=LA

I'm surprised they didn't just jump straight to the final report, as that's exactly what happened.

[rwanttaja]

...And will I improve the fuel system to prevent what we suspect happened (that in high turbulence I most likely kicked the barbed fuel fitting at the bottom of the tank, which is placed to where that can happen)? Most definitely. I was wearing my steel toed work boots that day, so I could do that without feeling it. Then again, judging from the dents at the bottom of the fuel tank, those boots probably saved me from broken toes.

In light of the NTSB preliminary, I had to go back and review this earlier description. Please let us know what you come up with, and what you are implementing to keep it from happening again.

This reminds me of an incident almost 30 years ago, when I was one of the two people flying the original Fly Baby as part of a club within Chapter 26. The other member was flying, and one of the rudder cables came disconnected in the forward cockpit. He reached down and grabbed a handful of loose cable (it passes through the cockpit right by the pilot seat) and landed pretty much normally.

The post-mortem on this was interesting. Here's an overall view of the Fly Baby rudder system:

The rudder cable attaches to a turnbuckle up forward, which then attaches to a flat strap of steel with a series of holes to allow (ground adjustability). A drilled AN-3 bolt and castle nut held the turnbuckle to the strap, with a cotter pin.

Unfortunately, the bolt was installed so that the cotter pin was on the inside...next to the pilot's legs. Over ~10 years of flying, enough pants legs had slid past the cotter pin enough times that it eventually work-hardened and broke. So, eventually, the cotter pin came lose, the nut worked its way off, and the bolt fell out, disconnecting the rudder cable from the pedal.

Here's where the "duh" moment came in. Over my previous ~4 years of flying that airplane, I had occasionally noticed my pants cuff snagging on something whenever I got into the cockpit. My ape's brain said, "huh, something pointy down there" but the logical portion of my mind never said, "I wonder if it's a problem....?"

It sounds like Frank's fuel fitting might be along the same lines...a casually noted issue, without the inferential leap to anticipating a future problem.

It's a good lesson for all of us: Pay attention to these little things. NOTICE stuff like this.

Ron Wanttaja

[Frank Giger]

This is pretty close to the thinking I'm having on the root causes of the leak.

Because the sump dump was on the outside right of the firewall, the hose for it couldn't be lower than it was - and so the hose for it had to be above it.

I had the brass barb fitting pointing straight down from the bottom of the tank, with the hose going down, to the right above the runner that holds the rudder, and then into it. While the hose was clear of the rudder pedal itself, there was some slack as well.

So it could be a couple things:

1) Like the Fly Baby, as I was entering (or more likely, exiting) the aircraft I had been brushing the brass fitting (there was nothing around it, and it's a tight cockpit) and weakened it.

2) During the turbulence it either finally broke, the tubing moved to be caught by the rudder and pulled to snap it (which I'm starting to really think about), or

3) I somehow kicked it (less likely).

As to how to make it to where that's not going to happen again, I've been thinking of more than just a few improvements.

1) Move the exterior sump drain as close to center of the firewall as I can, and if I can't , put it through the floor. To heck with having a hose near a moving part.

2) AN fitting with a little cage of some sort around it.

[Floatsflyer]

Frank, just keep standing upright, putting one foot in front of the other and keep on having as many birthdays as you can stand!

[Sam Buchanan]

Frank, the sump on my D.VII developed a crack so I ditched the sump and redesigned the tank with an RV fuel pickup and an AN fitting for the fuel line. Sumping is accomplished via a gascolator on the engine side of the firewall. This is a much more "aircrafty" installation and is working nicely. Let me know if you would like some photos.

[Frank Giger]

I'd love some, of course!

gigerfr (at) att (dot) net is my addy.

[Sam Buchanan]

Photos on the way.

[Frank Giger]

Are you going up to Russ' place at the end of the month? Are you bringing your plane?

[Sam Buchanan]

Are you going up to Russ' place at the end of the month? Are you bringing your plane?

My plane doesn't travel very far.

[Frank Giger]

I figured you had a high-speed trailer!