Home > VansAirForceForums

-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.

Old 12-11-2020, 08:20 AM
mikelupo mikelupo is offline
Join Date: Jan 2020
Location: Massachusetts
Posts: 34
Default Chafing can kill you

Dear Builders,
Please take chafing serious. During condition inspection, we are finding things that are darn scary. Scat tube, left unfettered can cut deep into softer metals.

The links below are to photos in my google drive. All photos are from my recently purchased RV-10.

The Fuel line chafing is inside the cabin "tunnel". Meaning, in the cabin with the pilot and passengers. The scat tube is what supplies cabin heat to the rear seats and it's unsupported and chafing into the fuel line. This is an in-flight hazard as you could end up with fuel leaking into the cabin area and possibly igniting. This would likely not be survivable in the air.

Fuel Line Chafing

These two photos are fore of the firewall in the engine compartment. The scat tube was chafing into the oil cooler. It goes without saying the bad things that could happen from a catastrophic oil leak.
Oil Cooler Chafing 1

Oil Cooler Chafing 2
RV-10 (purchased)
Sonex builder - EAA chapter project

Last edited by mikelupo : 12-15-2020 at 08:31 AM.
Reply With Quote
Old 12-11-2020, 10:05 AM
Ron B. Ron B. is offline
Join Date: Nov 2007
Location: Yarmouth, Nova Scotia
Posts: 2,487

Just changed out one of my heater SCAT hoses on my 14. A hose clamp had poked a hole. Rotated the clamp so the tail would not make contact and dabbed
silicone between both parts to make sure.
You have to look for some of these problems, move the SCAT and look under.
Thanks Ron
RV-14 Flying
AirCam flying
Reply With Quote
Old 12-11-2020, 10:51 AM
Toobuilder's Avatar
Toobuilder Toobuilder is offline
Join Date: Jul 2009
Location: Mojave
Posts: 4,737

Thanks for the reminder. Many of us have been in aerospace for decades and learned long ago these seemingly "obvious" lessons. Its apparent that with the success of Van's kits and the constant influx of new builders, these lessons need to be relearned over and over again. Every aiplane I've inspected in the last 20 years has at least one either "obvious" safety fail or a "contrary to normal practice" installation. The most egregious being the main battery cable zip tied directly to the RH fuel line of my RV-8. This fuel line was UPSTREAM of the fuel selector, and located UNDER MY LEGS at the spar center section. The battery cable, zip tie, and fuel line ALL showed signs of chafing on each other. A leak, arc, and resulting uncontrolled fuel flow feeding a fire under my legs is too horrible to even consider - yet the previous owner BUILT THE AIRPLANE LIKE THIS!

THINK, People!
WARNING! Incorrect design and/or fabrication of aircraft and/or components may result in injury or death. Information presented in this post is based on my own experience - Reader has sole responsibility for determining accuracy or suitability for use.

Michael Robinson
Harmon Rocket II -SDS EFI
1940 Taylorcraft BL-65
1984 L39C
Reply With Quote
Old 12-11-2020, 11:28 AM
wcalvert's Avatar
wcalvert wcalvert is offline
Join Date: Jan 2019
Location: Anacortes Wa
Posts: 162

Steel Scat tube wire vs. Aluminum with grit and vibration thrown in... tonight at Ten
RV-7 Tipper
Bill (Wild) VA-165 '90-'93
Anacortes, Wa

Start 2/19 Emp complete 4/19 Wings complete 11/19 Fuse complete 6/20 Finish kit Complete 8/20 Electric/Avionics complete 9/20 Waiting on a motor...
- Been there, Donated 2021
Reply With Quote
Old 12-11-2020, 11:37 AM
rv8ch's Avatar
rv8ch rv8ch is online now
Join Date: Feb 2005
Location: LSGY
Posts: 3,558
Default skills and experience take time

Originally Posted by Toobuilder View Post
Thanks for the reminder. Many of us have been in aerospace for decades and learned long ago these seemingly "obvious" lessons. Its apparent that with the success of Van's kits and the constant influx of new builders, these lessons need to be relearned over and over again. ...
I think you are right. I spend a lot of time on this site, reading whatever books I can find, webinars, other youtube videos, NTSB, etc. I really enjoy it, and I feel like I'm learning a lot. However, this is a massive investment in time that I realize most people don't have. Even still, I'm learning "do it wrong and you die" stuff all the time.

From what I have seen, the RV-14 kit is doing a great job of making it easier and easier for inexperienced builders to do it the right way. The the instructions are excellent, and from what I hear, the kit itself is also excellent.

I think that Van's is on the right track - make it easier to do it the right way rather than the wrong way. Teaching every builder 20+ years of aerospace "tribal knowledge" is much harder.
Mickey Coggins
"Hello, world!"
Reply With Quote
Old 12-11-2020, 01:17 PM
agent4573 agent4573 is offline
Join Date: Aug 2019
Location: Mountain view
Posts: 246

Sorry these are so small, but here's what happens if a braided oil line chafes your engine mount.

>>From the Moderator: Just tap or click the image thumbnail and it’ll open in larger living color in a separate tab.<<
Attached Thumbnails
Click image for larger version

Name:	-8629977530599775121.jpg
Views:	574
Size:	144.8 KB
ID:	5619  Click image for larger version

Name:	6315130768647966458.jpg
Views:	569
Size:	165.3 KB
ID:	5620  

2020 dues paid.

Last edited by scrollF4 : 12-12-2020 at 06:36 AM.
Reply With Quote
Old 12-11-2020, 03:59 PM
Roadjunkie1's Avatar
Roadjunkie1 Roadjunkie1 is offline
Join Date: Jun 2017
Location: Erie, Colorado
Posts: 88

"I built this airplane; NO ONE knows it better than I do...." Yes, well, that may be true. But did you do everything correctly? Your DAR may have picked up a few things but there may be other things lurking unnoticed. Sometimes it's a good thing to have someone accompany you (an A&P or IA or other builder you trust) on your Conditional Inspection. They might see things you have seen for so long they look OK to you. You're not the builder? All the more reason to have someone look at the airplane. Not all IA's are familiar with experimental aircraft and someone who has built an RV already may be a better choice.

I have inspected other aircraft, some flying and some ready to fly and found things that make my eyes get big! I have seen things in airplanes in various stages of being built (one by an A&P from an airline) that were not quite right.

LOOK at things with a critical eye. If it doesn't look exactly right, it probably isn't. This is something that is suspending your butt in the AIR, for crying out loud........!!!
Reply With Quote
Old 12-11-2020, 05:13 PM
Foghorn's Avatar
Foghorn Foghorn is offline
Join Date: Feb 2018
Location: Virginia Beach
Posts: 176

Just so we're all on the same sheet of music it's Condition Inspection not conditional Inspection.

I'm about to have the fuselage complete, engine to tail feathers. Once done I'll invite my EAA chapter to have a hangar visit and look at everything for an extra set of eyes. I'm sure they'll find something.
Jeff Parker
RV8 Fastback - Building (N767TS)
C195 - Flying (N4469C)
2020 dues paid
Reply With Quote
Old 12-11-2020, 05:14 PM
bruceh's Avatar
bruceh bruceh is offline
Join Date: Mar 2008
Location: Ramona, CA
Posts: 2,416

We found this bit of SCAT tubing rubbing up against a heat shield on Josh's RV-9A during an inspection last week.

The tubing was up tight against the heat shield and the only real visible indication was the black coloration where it had rubbed.
Bruce Hill
RV-9A N5771H flown over 800 hours!
APRS Tracking for KJ6YRP and New Flying Blog
2020 VAF donator
EAA Tech Counselor, Build assistance - canopy/tanks/fiberglass/electrical/repairs
Reply With Quote
Old 12-11-2020, 06:45 PM
Paul K Paul K is offline
Join Date: Mar 2009
Location: Grand Rapids, MI
Posts: 1,014

Iím a little shocked that anyone would have anything unsupported and allowed to come into contact with anything else FWF or anyplace else on the entire airplane! Iím serious!!!!! This is a pet peeve of mine and when other builders or owners have their cowls open, Iím right in there showing them potential problems. Iím not bashful about it and most appreciate it. Sorry, this stuff scares the heck out of me!

Conversely, I invite anyone who is around when my cowl is open to look around for anything I may have missed. I tell them not to hold anything back.
Paul K
West Michigan

Unfortunately in science, what you believe is irrelevant.

2021 donation made, exempt but worth every dime!
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -6. The time now is 01:31 PM.

The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.