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  #11  
Old 03-17-2017, 06:09 AM
Pat Stewart Pat Stewart is offline
 
Join Date: Jan 2005
Location: Granbury Texas
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My apologies, Walt is correct, I do start to get a little defensive of the RV nose gear incidents as most are usually do to a nose gear landing.
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  #12  
Old 03-17-2017, 07:22 AM
boandrv7a boandrv7a is offline
 
Join Date: Mar 2017
Location: denver
Posts: 37
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Quote:
Originally Posted by Pat Stewart View Post
No information in this video other than what a nose gears looks like when you land on it or maybe have the aircraft severely crabbed at nose gear touch down. The opportunity to learn is what was experience in the windy conditions, was it a cross wind, what was the wind speed, was there some type of shear and how did the aircraft respond to pilot input in those conditions.

As far as gear failure on its own we have all seen years of this issue and know the gear just does not fail on roll out for no reason. Is the RV nose gear less forgiving than a Cessna 150 when you land on it, absolutely.
Hey Pat - Sorry, I was not flying the plane when the incident happened, so I'm not certain what the actual conditions were and what mistakes were made. The pilot said he bounced and the conditions had gone from calm to gusty.

Jim
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Last edited by boandrv7a : 03-17-2017 at 07:24 AM.
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  #13  
Old 03-17-2017, 06:22 PM
Bill Dicus Bill Dicus is offline
 
Join Date: Jan 2005
Location: Shorewood, WI (Milwaukee area)
Posts: 1,050
Default Nos gear

Vans has been flying RV 6 A's, RV 7A's, RV 8A's and 9A's for many years and as far as I know I has not experienced a nosewheel failure. This suggests that there is a pilot factor that comes to play in many of these failures. Some of the underlying damage may have been done on prior landing attempts that did not go perfectly well. If this happened to me I would be sure to have additional instruction and practice in proper technique of minimizing loads on the nose wheel occurring on landing. Also might install the Anti Splat mods. Hope that no one suffers a repeat...
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  #14  
Old 03-17-2017, 07:21 PM
rockwoodrv9 rockwoodrv9 is offline
 
Join Date: Dec 2011
Location: Meridian ID, Aspen CO
Posts: 2,136
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Im willing to accept that 100% of the nose gear failures is either pilot or builder error. That does not change the numbers on how many nose gear failures there has been. Making them stronger to be able to handle a bit more abuse would not be a bad thing. I don't think there are many things that have ever been built that can't be improved. The 10 gear is better and the 14 gear is an upgrade too. This is NOT a dig on the original design of the gear. It was designed to be light, not taxied on uneven ground, and to be held off the ground until you are parked. It works great for the design goals.

I am still taking lessons and I know if I had landed my 9A the same as I landed the 172 yesterday, I would have rolled the gear and gone over. If I had the engineering skills, I would try to redesign the mount and gear to make it stronger. If it cost 10 pounds - I would be ok with that. I have a FP Catto and a light battery so my nose weight would still be fine. I appreciate Alan for the AntiSplat bar and nose wheel bearing that I am installing on my plane.

As I get closer to completion, I am looking to install larger tires that can handle a bit bigger bump on the taxi way or runway. I will be taking transition training and get my license before I finish, so I still have a chance!

This is probably the plane I need! https://www.youtube.com/watch?v=Qa12..._mpmubIneBskiB
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  #15  
Old 03-17-2017, 08:46 PM
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TJCF16 TJCF16 is offline
 
Join Date: Mar 2015
Location: Greenville SC
Posts: 82
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One thing I have do on my annual condition inspection is change the nose gear bolt,washer and nut. I will do it every year. I also pull the nose gear out and inspect for cracks etc. This gives me a good look at the bolt to see if there is any evidence of gouging as if it had tried to shear! Or had a shear load on it. So far so good!
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  #16  
Old 03-18-2017, 04:40 AM
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Bayou Bert Bayou Bert is offline
 
Join Date: Sep 2012
Location: Prairieville, LA
Posts: 196
Default Taper Pin

Last year when I had the engine off, I did the taper Pin mod where
the nose gear mounts to the engine mount. There is no slack now, like
there is with a bolt. I already had all the AntiSplat nose wheel mods
in place. Always taxi with stick all the way back, as well on beginning of
take off roll.
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  #17  
Old 03-18-2017, 06:15 AM
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plehrke plehrke is offline
 
Join Date: Sep 2006
Location: Defiance, MO
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Quote:
Originally Posted by Walt View Post
http://www.vansaircraft.com/pdf/sb14-12-22.pdf

If I'm not mistaking, SB 14-12-22, which came out over 2 years ago, was the result of an incorrectly installed stop flange which caused the NLG retainer bolt to fail.
This was likely a contributor, or possibly the direct cause of, the failure in this case as well.

From the SB:

"Vanís Aircraft has received reports of damage resulting from the WD-631-PC or WD-1031 Nose Stop Flange (stop flange) having been oriented incorrectly during installation. If the stop flange is installed incorrectly, it will allow insufficient rotation of the nose fork during tight taxi turns and can cause the tire to drag sideways. This induces excessive loads on the stop flange, nose gear leg, engine mount and the associated attach hardware."
To me, and I am an aerospace structural design engineer, this gear failure looks different then others as it looks like it failed due to more side loads then the others. The gear is bent to the side as apposed to others are straight aft.
Like any engineer should admit, my opinion is an opinion and only based on the very limited view I observed from the video. When I just watched the part 2 video there was no video of the nose gear off the aircraft. Was this edited out?
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  #18  
Old 03-18-2017, 06:58 AM
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AlexPeterson AlexPeterson is offline
 
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Location: Maple Grove, MN
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Quote:
Originally Posted by Walt View Post
The stop flange was incorrectly installed as can be seen in the video and confirmed by the OP, this can cause the upper retainer bolt to shear with the resulting nose gear collapse.
Just to amplify what Walt has said - if the flange is incorrectly installed, every single time one does a tight turn while moving the plane or taxiing, the nose wheel is prevented from pivoting far enough by the flange. This causes a large torque to be transmitted up the gear leg, which can only be resolved by the mounting bolt.

A properly installed flange will allow the nose wheel to pivot far enough so that the airplane can be turned with one main gear not moving.
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  #19  
Old 03-18-2017, 07:55 AM
boandrv7a boandrv7a is offline
 
Join Date: Mar 2017
Location: denver
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Quote:
Originally Posted by plehrke View Post
To me, and I am an aerospace structural design engineer, this gear failure looks different then others as it looks like it failed due to more side loads then the others. The gear is bent to the side as apposed to others are straight aft.
Like any engineer should admit, my opinion is an opinion and only based on the very limited view I observed from the video. When I just watched the part 2 video there was no video of the nose gear off the aircraft. Was this edited out?
I had the nose-gear and engine mount over at the A/P, so I didn't get any video of it, but I will.

Jim
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  #20  
Old 03-18-2017, 08:55 AM
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bret bret is offline
 
Join Date: Feb 2010
Location: Gardnerville Nv.
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I also went the taper pin method, does anyone know if this pin has the same strength as the AN hardware it replaced, it is a larger diameter so maybe stronger?
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