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bakerocb
Joined: 15 Jan 2006
Posts: 727
Location: FAIRFAX VA
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 Posted: Sun Aug 03, 2014 3:47 am Post subject: N819PR Nose Gear Failure |
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8/3/2014
Hello Galin, You wrote: “I am also contemplating having the new pin made
from steel instead of aluminum even with the dissimilar metal corrosion
issue.”
I would not accept an aluminum pin in such a high stress location. I am
surprised that such material was used in the first place.
As for dissimilar metal corrosion here is some information on that issue:
http://www.galvanizeit.org/design-and-fabrication/design-considerations/dissimilar-metals-in-contact
http://en.wikipedia.org/wiki/Galvanic_corrosion
I would like to stress the factor of current flow being the cause of such
corrosion and the much reduced factor of current flow when the two metals
are frequently moving against each other, instead of having a static
connection, and the further reduction of current flow by some intervening
substance such as grease. See here:
“Ensure there is no contact with an electrolyte. This can be done by using
water-repellent compounds such as greases, or by coating the metals with an
impermeable protective layer, such as a suitable paint, varnish, or
plastic.”
It may take a bit of searching around, but you may even find a single long
AN bolt that could replace the pin. Or, as has been already mentioned, use
two shorter AN bolts. In addition to any grease involved these bolts would
also have the initial protection against corrosion because of the cadmium
plating.
OC
==========================================================
From: Galin Hernandez
Sent: Friday, August 01, 2014 11:03 AM
To: kis-list(at)matronics.com
Subject: Re: N819PR Nose Gear Failure
On Jul 31, 2014, at 10:38 PM, Galin Hernandez <galinhdz(at)gmail.com> wrote:
I contacted CATTO Props today but they are all at OSH so if somebody gets to
talk to them ask about a 3 bladed composite for a KIS4 with Lycoming O360
180HP engine. 
Now for the ongoing nose gear saga:
It turns out the rear pin on the nose gear assembly sheared which caused the
gear to collapse. The shear was clean and it was obvious (corrosion) the pin
had started breaking well before the failure. It sheared right where the "H"
bracket meets the firewall bracket and this explains why the visual
inspection done during the annual did not find it. To see the problem
happening you have to remove the pin there is no other way to inspect the
area. I recommend everyone pull and check their rear "H" bracket pin to see
if they are experiencing the same issue or not. If you do please let us know
what your find, good or bad, so if there is a trend we can identify it.
I plan to pull and inspect the new pin after 50hr or 50 landing (whichever
comes first) and at the annual. If I experience a bad shimmy at any time
(due to over grease or lack of friction) I will pull and inspect the pin
since this places a lot of stress on that specific part of that pin. After a
few inspections I will decide if it needs to be inspected on a continuous
basis or I just got a bad pin. I am also contemplating having the new pin
made from steel instead of aluminum even with the dissimilar metal corrosion
issue. Steel or aluminum I will do the above inspections no matter what the
pin is eventually made from.
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Robert Reed
Joined: 22 Oct 2009
Posts: 331
Location: Dallas/Ft.Worth
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| Posted: Sun Aug 03, 2014 8:12 pm Post subject: N819PR Nose Gear Failure |
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|
Galin,
I have been thinking about this since you first reported the gear failure. I can't help but wonder if the exhaust failure had an effect on the H-Bracket that wouldn't have been so obvious. Since the bracket is formed from Aluminum and you had to replace the pin was it possible that the hole in the bracket was somehow compromised allowing movement of the pin that resulted in the failure. My thought is that the heating of the bracket might have allowed the hole to expand or elongate allowing excess movement of the pin.
I am just suspicious that the pin failed after such a short period following the exhaust problem even though it has lasted for a long time prior to that event.
Just some ramblings of an old fool so feel free to ignore.
Bob
From: Galin Hernandez <galinhdz(at)gmail.com>
To: "kis-list(at)matronics.com" <kis-list(at)matronics.com>
Sent: Friday, August 1, 2014 10:35 AM
Subject: Re: N819PR Nose Gear Failure
If it was your idea I think you made a wise decision.
On Fri, Aug 1, 2014 at 11:20 AM, Alfred Rosa <fredorosa(at)gmail.com (fredorosa(at)gmail.com)> wrote: | Quote: | Galin, I'm out of town and can't send pictures till I get back in 10 days. My H does connect to the firewall brackets with two short AN bolts which are almost impossible to break.
Don't remember if that was the design or my beefing up mod. Sent from my iPhone
On Aug 1, 2014, at 11:03 AM, Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)> wrote:
| Quote: | Al; Here is aphoto of the "H" bracket where you can see the rear aluminum pin just underneath the fuselage.
Can you send a photo of your set up? I wonder if they changed the design and now use 2 steel bolts instead of one aluminum pin. This would really strengthen the point where the "H" bracket connect to the firewall brackets which is what I was thinking with my idea of a steel pin.
On Fri, Aug 1, 2014 at 6:24 AM, Alfred Rosa <fredorosa(at)gmail.com (fredorosa(at)gmail.com)> wrote: | Quote: | Galin,
I'm having a hard time trying to understand what you mean by the rear pin. My H bracket connects to the firewall brackets with two bolts.
AlSent from my iPhone
On Jul 31, 2014, at 10:38 PM, Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)> wrote:
| Quote: | I contacted CATTO Props today but they are all at OSH so if somebody gets to talk to them ask about a 3 bladed composite for a KIS4 with Lycoming O360 180HP engine.
Now for the ongoing nose gear saga:
It turns out the rear pin on the nose gear assembly sheared which caused the gear to collapse. The shear was clean and it was obvious (corrosion) the pin had started breaking well before the failure. It sheared right where the "H" bracket meets the firewall bracket and this explains why the visual inspection done during the annual did not find it. To see the problem happening you have to remove the pin there is no other way to inspect the area. I recommend everyone pull and check their rear "H" bracket pin to see if they are experiencing the same issue or not. If you do please let us know what your find, good or bad, so if there is a trend we can identify it.
I plan to pull and inspect the new pin after 50hr or 50 landing (whichever comes first) and at the annual. If I experience a bad shimmy at any time (due to over grease or lack of friction)I will pull and inspect the pin since this places a lot of stress on that specific part of that pin. After a few inspections I will decide if it needs to be inspected on a continuous basis or I just got a bad pin. I am also contemplating having the new pin made from steel instead of aluminum even with the dissimilar metal corrosion issue. Steel or aluminum I will do the above inspections no matter whatthe pin is eventually made from.
On Wed, Jul 30, 2014 at 4:44 PM, Tim Yoder <ftyoder(at)yoderbuilt.com (ftyoder(at)yoderbuilt.com)> wrote: | Quote: | Galin,
You might talk to Scott Stearns, he had a Prince prop on his carbon TR-1C with a 220 HP O-360 and has changed to a different prop. A friend got a three blade Catto for his RV7 that took six months to get but he likes it. The Prince P-Tip is not the most efficient design and I'm sure you know that two blades are more efficient than three, as Bob mentioned, assuming you have ground clearance. I also believe that MT has a mandatory 10 yr. overhaul on it's adjustable props. That cost allot also.
Tim
From: owner-kis-list-server(at)matronics.com (owner-kis-list-server(at)matronics.com) [mailto:owner-kis-list-server(at)matronics.com (owner-kis-list-server(at)matronics.com)] On Behalf Of Galin Hernandez
Sent: Wednesday, July 30, 2014 1:08 PM
To: kis-list(at)matronics.com (kis-list(at)matronics.com)Subject: Re: N819PR Nose Gear Failure
THANKS for the info Bob.
Is anybody running a fixed pitch composite 3 bladed prop on a TR-4? I want some basic inputs from actual use before I make a decision. MT, Prince and even Sensenich are high on my list.
On Wed, Jul 30, 2014 at 3:26 PM, Robert Reed <robertr237(at)att.net (robertr237(at)att.net)> wrote: | Quote: | Galin,
Catto didn't have a model number for the prop, he basically did a custom based on engine horsepower, RPM, and airspeed for the aircraft. He also included desired two blade or three blade configuration. I went with three blade out of desire to have quite operation over power performance because of Sharon's migraines. Catto now has the leading edge protection on his props.
I looked at Prince and can't remember why I excluded them but it seems that their prop wasn't rated for the Lycoming 360 engine at that time. I also looked at MT Props but they were a bit on the expensive side as I recall. I really liked their electric constant speed option though and would probably have gone with that if money weren't a primary concern.
Hope that helps,
Bob
From: Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)>To: "kis-list(at)matronics.com (kis-list(at)matronics.com)" <kis-list(at)matronics.com (kis-list(at)matronics.com)>
Sent: Wednesday, July 30, 2014 1:08 PM Subject: Re: N819PR Nose Gear Failure
Bob; What model prop did you wind up buying from Catto? Does it have a particular model number/designation?
On Thu, Jul 24, 2014 at 9:42 AM, Owen Baker <bakerocb(at)cox.net (bakerocb(at)cox.net)> wrote: | Quote: | 7/24/2014
Hello Galin, You wrote: “.... composite props and rain don't mix very well....”
Would you consider a prince propeller with leading edge protection?
http://www.princeaircraft.com/
OC
=========
From: Galin Hernandez (galinhdz(at)gmail.com)
Sent: Thursday, July 24, 2014 8:46 AM
To: kis-list(at)matronics.com (kis-list(at)matronics.com)
Subject: Re: N819PR Nose Gear Failure
Initial check by the mechanic indicates no firewall damage at all, so the actual damage is not a big deal. Engine will be completely overhauled, a new nose gear installed, a new propeller installed, some fiberglass work done and the airplane will be better than before. The airplane is a whole lot stronger than it looks.
The rear pin on the landing gear "H" bracket broke letting the entire assembly rotate 180 degrees backwards. Once this happened the main tube held up for a little bit but eventually collapsed under the different stress. I will ask Lyle if he can make the landing gear rear pin a little bigger to better withstand the landing loads.
I will definitely look at moving the main gear an inch or two further forward but not sure if it can be done at this stage. The other option is to go with a CATTO composite prop, which is lighter than the SENSENICH aluminum prop I have, but composite props and rain don't mix very well and I fly real IMC.
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sstearns2(at)yahoo.com
Guest
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| Posted: Sun Aug 03, 2014 10:14 pm Post subject: N819PR Nose Gear Failure |
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I would go with the whirlwind ground adjustable. I just flew to Oshkosh and back behind it. It is about the same weight and price as my old prince prop, but you can adjust the pitch to be exactly optimum.
Are you going with a stock overhaul? Are you concidering porting/flow balancing or higher compression pistons?
Scott
On Sunday, August 3, 2014 9:15 PM, Robert Reed <robertr237(at)att.net> wrote:
Galin,
I have been thinking about this since you first reported the gear failure. I can't help but wonder if the exhaust failure had an effect on the H-Bracket that wouldn't have been so obvious. Since the bracket is formed from Aluminum and you had to replace the pin was it possible that the hole in the bracket was somehow compromised allowing movement of the pin that resultedin the failure. My thought is that the heating of the bracket might have allowed the hole to expand or elongate allowing excess movement of the pin.
I am just suspicious that the pin failed after such a short period following the exhaust problem even though it has lasted for a long time prior to that event.
Just some ramblings of an old fool so feel free to ignore.
Bob
From: Galin Hernandez <galinhdz(at)gmail.com>
To: "kis-list(at)matronics.com" <kis-list(at)matronics.com>
Sent: Friday, August 1, 2014 10:35 AM
Subject: Re: N819PR Nose Gear Failure
If it was your idea I think you made a wise decision.
On Fri, Aug 1, 2014 at 11:20 AM, Alfred Rosa <fredorosa(at)gmail.com (fredorosa(at)gmail.com)> wrote: | Quote: | Galin, I'm out of town and can't send pictures till I get back in 10 days. My H does connect to the firewall brackets with two short AN bolts which are almost impossible to break.
Don't remember if that was the design or my beefing up mod. Sent from my iPhone
On Aug 1, 2014, at 11:03 AM, Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)> wrote:
| Quote: | Al; Here is a photo of the "H" bracket where you can see the rear aluminum pin just underneath the fuselage.
Can you send a photo of your set up? I wonder if they changed the design and now use 2 steel bolts instead of one aluminum pin. This would really strengthen the point where the "H" bracket connect to the firewall brackets which is what I was thinking with my idea of a steel pin.
On Fri, Aug 1, 2014 at 6:24 AM, Alfred Rosa <fredorosa(at)gmail.com (fredorosa(at)gmail.com)> wrote: | Quote: | Galin,
I'm having a hard time trying to understand what you mean by the rear pin. My H bracket connects to the firewall brackets with two bolts.
AlSent from my iPhone
On Jul 31, 2014, at 10:38 PM, Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)> wrote:
| Quote: | I contacted CATTO Props today but they are all at OSH so if somebody gets to talk to them ask about a 3 bladed composite for a KIS4 with Lycoming O360 180HP engine.
Now for the ongoing nose gear saga:
It turns out the rear pin on the nose gear assembly sheared which caused the gear to collapse. The shear was clean and it was obvious (corrosion) the pin had started breaking well before the failure. It sheared right where the "H" bracket meets the firewall bracket and this explains why the visual inspection done during the annual did not find it. To see the problem happening you have to remove the pin there is no other way to inspect the area. I recommend everyone pull and check their rear "H" bracket pin to see if they are experiencing the same issue or not. If you do please let us know what your find, good or bad, so if there is a trend we can identify it.
I plan to pull and inspect the new pin after 50hr or 50 landing (whichever comes first) and at the annual. If I experience a bad shimmy at any time (due to over grease or lack of friction) I will pull and inspect the pin since this places a lot of stress on that specific part of that pin. After a few inspectionsI will decide if it needs to be inspected on a continuous basis orI just got a bad pin. I am also contemplating having the new pin made from steel instead of aluminum even with the dissimilar metal corrosion issue. Steel or aluminum I will do the above inspections no matter whatthe pin is eventually made from.
On Wed, Jul 30, 2014 at 4:44 PM, Tim Yoder <ftyoder(at)yoderbuilt.com (ftyoder(at)yoderbuilt.com)> wrote: | Quote: | Galin,
You might talk to Scott Stearns, he had a Prince prop on his carbon TR-1C with a 220 HP O-360 and has changed to a different prop. A friend got a three blade Catto for his RV7 that took six months to get but he likes it. The Prince P-Tip is not the most efficient design and I'm sure you know that two blades are more efficient than three, as Bob mentioned, assuming you have ground clearance. I also believe that MT has a mandatory 10 yr. overhaul on it's adjustable props. That cost allot also.
Tim
From: owner-kis-list-server(at)matronics.com (owner-kis-list-server(at)matronics.com) [mailto:owner-kis-list-server(at)matronics.com (owner-kis-list-server(at)matronics.com)] On Behalf Of Galin Hernandez
Sent: Wednesday, July 30, 2014 1:08 PM
To: kis-list(at)matronics.com (kis-list(at)matronics.com)Subject: Re: N819PR Nose Gear Failure
THANKS for the info Bob.
Is anybody running a fixed pitch composite 3 bladed prop on a TR-4? I want some basic inputs from actual use before I make a decision. MT, Prince and even Sensenich are high on my list.
On Wed, Jul 30, 2014 at 3:26 PM, Robert Reed <robertr237(at)att.net (robertr237(at)att.net)> wrote: | Quote: | Galin,
Catto didn't have a model number for the prop, he basically did a custom based on engine horsepower, RPM, and airspeed for the aircraft. He also included desired two blade or three blade configuration. I went with three blade out of desire to have quite operation over power performance because of Sharon's migraines. Catto now has the leading edge protection on his props.
I looked at Prince and can't remember why I excluded them but it seems that their prop wasn't rated for the Lycoming 360 engine at that time. I also looked at MT Props but they were a bit on the expensive side as I recall. I really liked their electric constant speed option though and would probably have gone with that if money weren't a primary concern.
Hope that helps,
Bob
From: Galin Hernandez <galinhdz(at)gmail.com (galinhdz(at)gmail.com)>To: "kis-list(at)matronics.com (kis-list(at)matronics.com)" <kis-list(at)matronics.com (kis-list(at)matronics.com)>
Sent: Wednesday, July 30, 2014 1:08 PM Subject: Re: N819PR Nose Gear Failure
Bob; What model prop did you wind up buying from Catto? Does it have a particular model number/designation?
On Thu, Jul 24, 2014 at 9:42 AM, Owen Baker <bakerocb(at)cox.net (bakerocb(at)cox.net)> wrote: | Quote: | 7/24/2014
Hello Galin, You wrote: “.... composite props and rain don't mix very well....”
Would you consider a prince propeller with leading edge protection?
http://www.princeaircraft.com/
OC
=========
From: Galin Hernandez (galinhdz(at)gmail.com)
Sent: Thursday, July 24, 2014 8:46 AM
To: kis-list(at)matronics.com (kis-list(at)matronics.com)
Subject: Re: N819PR Nose Gear Failure
Initial check by the mechanic indicates no firewall damage at all, so the actual damage is not a big deal. Engine will be completely overhauled, a new nose gear installed, a new propeller installed, some fiberglass work done and the airplane will be better than before. The airplane is a whole lot stronger than it looks.
The rear pin on the landing gear "H" bracket broke letting the entire assembly rotate 180 degrees backwards. Once this happened the main tube held up for a little bit but eventually collapsed under the different stress. I will ask Lyle if he can make the landing gear rear pin a little bigger to better withstand the landing loads.
I will definitely look at moving the main gear an inch or two further forward but not sure if it can be done at this stage. The other option is to go with a CATTO composite prop, which is lighter than the SENSENICH aluminum prop I have, but composite props and rain don't mix very well and I fly real IMC.
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Keith.Miller(at)esa.int
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| Posted: Mon Aug 04, 2014 12:27 am Post subject: N819PR Nose Gear Failure |
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|
I never liked the idea of the pins in the nose gear so i replaced them with
cad plated bolts and grease them up each annual .
In addition to being stronger than the pins they also take up a lot of
side movements .
here is a picture :
(See attached file: DSCN0225.JPG)
From: "Owen Baker " <bakerocb(at)cox.net>
To: <kis-list(at)matronics.com>, "HERNANDEZ GALIN" <galinhdz(at)gmail.com>,
Date: 08/03/2014 01:49 PM
Subject: KIS-List: N819PR Nose Gear Failure
Sent by: owner-kis-list-server(at)matronics.com
8/3/2014
Hello Galin, You wrote: “I am also contemplating having the new pin made
from steel instead of aluminum even with the dissimilar metal corrosion
issue.”
I would not accept an aluminum pin in such a high stress location. I am
surprised that such material was used in the first place.
As for dissimilar metal corrosion here is some information on that issue:
http://www.galvanizeit.org/design-and-fabrication/design-considerations/dissimilar-metals-in-contact
http://en.wikipedia.org/wiki/Galvanic_corrosion
I would like to stress the factor of current flow being the cause of such
corrosion and the much reduced factor of current flow when the two metals
are frequently moving against each other, instead of having a static
connection, and the further reduction of current flow by some intervening
substance such as grease. See here:
“Ensure there is no contact with an electrolyte. This can be done by using
water-repellent compounds such as greases, or by coating the metals with an
impermeable protective layer, such as a suitable paint, varnish, or
plastic.”
It may take a bit of searching around, but you may even find a single long
AN bolt that could replace the pin. Or, as has been already mentioned, use
two shorter AN bolts. In addition to any grease involved these bolts would
also have the initial protection against corrosion because of the cadmium
plating.
OC
==========================================================
From: Galin Hernandez
Sent: Friday, August 01, 2014 11:03 AM
To: kis-list(at)matronics.com
Subject: Re: KIS-List: N819PR Nose Gear Failure
On Jul 31, 2014, at 10:38 PM, Galin Hernandez <galinhdz(at)gmail.com> wrote:
I contacted CATTO Props today but they are all at OSH so if somebody gets to
talk to them ask about a 3 bladed composite for a KIS4 with Lycoming O360
180HP engine.
Now for the ongoing nose gear saga:
It turns out the rear pin on the nose gear assembly sheared which caused the
gear to collapse. The shear was clean and it was obvious (corrosion) the pin
had started breaking well before the failure. It sheared right where the "H"
bracket meets the firewall bracket and this explains why the visual
inspection done during the annual did not find it. To see the problem
happening you have to remove the pin there is no other way to inspect the
area. I recommend everyone pull and check their rear "H" bracket pin to see
if they are experiencing the same issue or not. If you do please let us know
what your find, good or bad, so if there is a trend we can identify it.
I plan to pull and inspect the new pin after 50hr or 50 landing (whichever
comes first) and at the annual. If I experience a bad shimmy at any time
(due to over grease or lack of friction) I will pull and inspect the pin
since this places a lot of stress on that specific part of that pin. After a
few inspections I will decide if it needs to be inspected on a continuous
basis or I just got a bad pin. I am also contemplating having the new pin
made from steel instead of aluminum even with the dissimilar metal corrosion
issue. Steel or aluminum I will do the above inspections no matter what the
pin is eventually made from.
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galinhdz(at)gmail.com
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| Posted: Mon Aug 04, 2014 1:20 pm Post subject: N819PR Nose Gear Failure |
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Bob; The pin, fuselage brackets and the "H" brackets are all new. I have to
verify with the mechanic working on this but it is possible that the rear
pin is stainless steel not aluminum but I am not sure. This would make a
big difference in shear strength. I could have just gotten a bad pin. Feces
occurs.
however, I need to insure the two fuselage brackets are properly aligned
because if not this can put a different stress on that pin it isn't
designed to take. But either way I am going to follow Al Rosa and Keith
Miller's lead by using aircraft bolts instead of a long pin. I think it
would be a wise thing for everyone to do.
On Mon, Aug 4, 2014 at 12:12 AM, Robert Reed <robertr237(at)att.net> wrote:
[quote] Galin,
I have been thinking about this since you first reported the
gear failure. I can't help but wonder if the exhaust failure had an effect
on the H-Bracket that wouldn't have been so obvious. Since the bracket is
formed from Aluminum and you had to replace the pin was it possible that
the hole in the bracket was somehow compromised allowing movement of the
pin that resulted in the failure. My thought is that the heating of the
bracket might have allowed the hole to expand or elongate allowing excess
movement of the pin.
I am just suspicious that the pin failed after such a short period
following the exhaust problem even though it has lasted for a long time
prior to that event.
Just some ramblings of an old fool so feel free to ignore.
Bob
*From:* Galin Hernandez <galinhdz(at)gmail.com>
*To:* "kis-list(at)matronics.com" <kis-list(at)matronics.com>
*Sent:* Friday, August 1, 2014 10:35 AM
*Subject:* Re: N819PR Nose Gear Failure
If it was your idea I think you made a wise decision.
On Fri, Aug 1, 2014 at 11:20 AM, Alfred Rosa <fredorosa(at)gmail.com> wrote:
Galin, I'm out of town and can't send pictures till I get back in 10 days
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mantafs(at)earthlink.net
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| Posted: Wed Aug 06, 2014 6:51 pm Post subject: N819PR Nose Gear Failure |
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I am fairly sure that this pin as originally designed was steel. Could the builder have changed this from the steel to aluminum at some time? Do others have an aluminum pin or steel?
Mark
--
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galinhdz(at)gmail.com
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| Posted: Wed Aug 06, 2014 7:09 pm Post subject: N819PR Nose Gear Failure |
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I checked with the mechanic and the pin is stainless steel, not aluminum.
My mistake.
After talking with Lyle Hendricks, he said the assemblies have been
shipping with AN bolts, not pins, for years now. He also told me that using
the "eye bolts" on the "H" bracket instead of just drilling a hole provides
a measure of compensation in case the firewall brackets are not perfectly
aligned. He said the bolts are rated at some 30,000lbs so the aluminum
firewall brackets or the aluminum "H" bracket will fail long before the
"eye bolts" do.
I ordered the new nose wheel assembly and it should ship by Friday.
On Wed, Aug 6, 2014 at 10:50 PM, Mark Kettering <mantafs(at)earthlink.net>
wrote:
[quote]
I am fairly sure that this pin as originally designed was steel. Could
the builder have changed this from the steel to aluminum at some time? Do
others have an aluminum pin or steel?
Mark
--
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bakerocb
Joined: 15 Jan 2006
Posts: 727
Location: FAIRFAX VA
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| Posted: Wed Aug 06, 2014 7:13 pm Post subject: N819PR Nose Gear Failure |
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8/6/2014
Hello Mark, The pin in kit #116, my KIS TR-1, was steel. I think that
aluminum would be entirely unsuitable for this use.
OC
=========================================================================
From: Mark Kettering
Sent: Wednesday, August 06, 2014 10:50 PM
To: kis-list(at)matronics.com
Subject: Re: N819PR Nose Gear Failure
I am fairly sure that this pin as originally designed was steel. Could the
builder have changed this from the steel to aluminum at some time? Do
others have an aluminum pin or steel?
Mark
================================================================================
From: Galin Hernandez
Sent: Aug 1, 2014 11:03 AM
To: "kis-list(at)matronics.com"
Subject: Re: N819PR Nose Gear Failure
Al; Here is a photo of the "H" bracket where you can see the rear aluminum
pin just underneath the fuselage. Can you send a photo of your set up? I
wonder if they changed the design and now use 2 steel bolts instead of one
aluminum pin. This would really strengthen the point where the "H" bracket
connect to the firewall brackets which is what I was thinking with my idea
of a steel pin.
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