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  #1  
Old 05-08-2021, 06:24 AM
design4p design4p is offline
 
Join Date: Jul 2018
Location: CORWEN
Posts: 61
Default RV14A Nose Wheel Fairing Detachment on Landing

Hi,

Has anyone had the same experience as me.

RV14 Nose Wheel Fairing Detachment on Landing.

I am in the process of flight testing covering the test schedules of the LAA (light Aircraft Association) in the UK and on landing after only 6 hours of flying the nose wheel fairing detached.

I have attached photos of the damage. I have re-assembled the parts with one layer of glass fibre on the fractured edges to try to establish the cause of the problem.

An idea is that the 8 countersunk screws are not sufficient to hold the Fairing to the Fairing Bracket. Also the large OD diameter of the washer within the Fork Nose axle bolt assembly (Washer 062 25783054) (Page 40A-07) the OD is too small.

Any suggestions of possible causes would be welcome.

Regards John
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  #2  
Old 05-08-2021, 06:50 AM
Nova RV Nova RV is offline
 
Join Date: Aug 2015
Location: Leesburg, VA
Posts: 572
Default

No problems in 170 hours. I use tinnerman washers on all of the attachment screws and have more tire clearance than called for around the bottom too. Perhaps the tire (tyre) deformed enough on landing to catch the edge of the wheel pant and ripped it off the mounting? Are there cut marks on the tire?
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Leesburg, VA

CFI-I ASMEL, ATP

RV-14A kit # 140243 (flying as of 11/18)

www.mykitlog.com/chrismoon/
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  #3  
Old 05-08-2021, 07:07 AM
lr172 lr172 is offline
 
Join Date: Oct 2013
Location: Schaumburg, IL
Posts: 6,537
Default

The crack in the attach bracket would seem to indicate that the mid to upper left side of the fairing hit a stationary object. No issues with the screws would caused the attach bracket to crack like that. The scrape marks in the paint seem to reinforce that speculation. They are too straight and symmetrical to have been caused by the fairing bouncing around after separation.
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N11LR - RV-10, Flying as of 12/2019

Last edited by lr172 : 05-08-2021 at 07:46 AM.
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  #4  
Old 05-08-2021, 07:14 AM
jeffkersey's Avatar
jeffkersey jeffkersey is offline
 
Join Date: Sep 2015
Location: Cottontown, TN
Posts: 312
Default Grass or paved?

it would seem to me that the tire pressure may have been low enough to allow it to compress and the fairing hit the runway or something on the runway. Were you landing on a moist/soft field? Did you take any divits? How fast were you going when you set the nose wheel down?
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  #5  
Old 05-08-2021, 10:17 AM
design4p design4p is offline
 
Join Date: Jul 2018
Location: CORWEN
Posts: 61
Default Thank you for the replies so far

Yes - I will be using tinnerman washers or similar in my new nose fairing for extra security.

I can't recall hitting any ground object as we did a runway check after picking up the pieces. The bracket was badly bent after the incident and I wanted to rebuild the assembly for ideas of cause and when trying to straightening the bracket the bracket broke at that that point.

The runway was a tarmacadam and reasonably smooth. The speed on touch down was 58 kts (from my G3X flight log), although it was a heavy landing.

Regards John
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  #6  
Old 05-08-2021, 10:32 AM
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jeffkersey jeffkersey is offline
 
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Location: Cottontown, TN
Posts: 312
Default Hold the nose wheel off...

Quote:
Originally Posted by design4p View Post
Yes - I will be using tinnerman washers or similar in my new nose fairing for extra security.

I can't recall hitting any ground object as we did a runway check after picking up the pieces. The bracket was badly bent after the incident and I wanted to rebuild the assembly for ideas of cause and when trying to straightening the bracket the bracket broke at that that point.

The runway was a tarmacadam and reasonably smooth. The speed on touch down was 58 kts (from my G3X flight log), although it was a heavy landing.

Regards John
My suggestion would be to hold the nose wheel off as long as possible whether on Tarmac or Grass. That goes for landing or takeoff. Just because the mains are on the ground does not mean you have to set the nose wheel down immediately. Hold it off till you cannot hold it off. I have not flown a 14a but in the 7A you can get very slow before the nose has to come down.
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  #7  
Old 05-08-2021, 10:37 AM
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jeffkersey jeffkersey is offline
 
Join Date: Sep 2015
Location: Cottontown, TN
Posts: 312
Default don't hit the brakes on landing...

Quote:
Originally Posted by jeffkersey View Post
My suggestion would be to hold the nose wheel off as long as possible whether on Tarmac or Grass. That goes for landing or takeoff. Just because the mains are on the ground does not mean you have to set the nose wheel down immediately. Hold it off till you cannot hold it off. I have not flown a 14a but in the 7A you can get very slow before the nose has to come down.
Also, make sure you toes are on the bottoms of the pedals on initial landing so you don't accidentally hit the brakes and slam the nose down.... Wait till you absolutely need braking before putting you toes at the top of the pedals and then apply brakes as gingerly as allowable for the runway left, al the while holding what back pressure on the stick it takes to keep the nose wheel off....
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  #8  
Old 05-08-2021, 10:41 AM
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rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 9,594
Default

Quote:
Originally Posted by design4p View Post
Hi,

Has anyone had the same experience as me.

RV14 Nose Wheel Fairing Detachment on Landing.

I am in the process of flight testing covering the test schedules of the LAA (light Aircraft Association) in the UK and on landing after only 6 hours of flying the nose wheel fairing detached.

I have attached photos of the damage. I have re-assembled the parts with one layer of glass fibre on the fractured edges to try to establish the cause of the problem.

An idea is that the 8 countersunk screws are not sufficient to hold the Fairing to the Fairing Bracket. Also the large OD diameter of the washer within the Fork Nose axle bolt assembly (Washer 062 25783054) (Page 40A-07) the OD is too small.

Any suggestions of possible causes would be welcome.

Regards John
This design is not exclusive to the RV-14A. It is the same basic design (wheel fairing and brackets) and installation as the RV-10 of which there are almost 1000 flying and 150+ RV-14A's. I don't remember hearing about an issue like this previously.

You don't show any of the hardware in your photos, or mention what was missing or loose. A bit more detail about "the fairing detached" would be helpful.
Are you saying that the fairing detached from the bracket at the 8 screw locations?
If so, did you by chance chase the nutplates with a tap to make the screws easier to install / remove?
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Scott McDaniels
Hubbard, Oregon
Van's Aircraft Engineering Prototype Shop Manager
FAA/DAR
RV-6A (aka "Junkyard Special ")
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  #9  
Old 05-08-2021, 03:47 PM
Ralph Inkster Ralph Inkster is offline
 
Join Date: Feb 2008
Location: Calgary, Alberta
Posts: 1,531
Default

Don't know how this might affect in the resulting failure, but looking at the pictures and than to the plans, it appears (to me anyhow) the mounting brackets are positioned farther back on the wheel pant than depicted in the plans.
Could the OP measure from the trailing edge of the wheel pant to where the AXLE would be. In the plans this dimension lists as 20 5/32", which would place the forward Allen mtg bolt hole approx 2" or so aft of the front/back pant flange.
If the brackets were mounted slightly aft (pant ending up forward) compared to the plans, I'm unsure if this may cause balance, buffeting, or shimmy issues that might lead to loosened brackets, or fatigue cracking.
Also looking at the pictures, appears the fiberglass was countersunk, possibly too deep and the screws could have worked loose. One way to get past that would be to install Tinnerman (dimpled) washers under the flush screws.
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built a few RVs, rebuilt a few more, hot rodded more, & maintained/updated a big bunch more

Last edited by Ralph Inkster : 05-08-2021 at 03:52 PM.
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  #10  
Old 05-08-2021, 04:14 PM
Aussieflyer Aussieflyer is offline
 
Join Date: Jan 2015
Location: Redcliffe, Queensland, Australia
Posts: 85
Default Insufficient Torque Adjustment

I had a similar issue with the front wheel spat at about the same hours of test flying. During the build I applied the torque required in the plans (26 I think).

The aircraft then sat on the front wheel for some time. The plane was towed to the paint shop and back. Unbeknown the torque was diminishing as the front wheel settled down after the initial torqueing.

It was time to go flying. The first few landings were fine. Then all of a sudden the front wheel commenced to shimmy wildly from wheel stop to wheel stop and bingo wheel spat damage (not as much as your photos depict).

I immediately suspected the torque setting had been lost and guess what? It was. Fixed the spat and retorqued the friction setting and 500 hours later nothing has gone wrong.

I'm surprised you did not mention the wild shimming. Therefore, perhaps it was not the same as mine. I warn everyone to re check the torque after your first flight. Vans told me this is common and once you have readjusted the torque setting a second time it should be good for ever. I still check it every annual because I have suffered unintended damage just like you. In five years it have been perfect every inspection. Vans was right you know.
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