L'Hotelier Fitting Safety Pins

Never mind! However, will a L'Hotelier fitting will come off even when pinned if it is too well lubricated, I have heard that is why I ask?


On Friday, October 14, 2016 at 8:28:07 AM UTC-7, wrote:
On Thursday, October 13, 2016 at 7:44:07 PM UTC-4, Jonathan St. Cloud wrote:
Was it a pinned L'Hotelier that failed on the Nimbus 4M crash in Washington? Does anyone know of failures with properly pinned L'Hotelier?

http://www.ntsb.gov/_layouts/ntsb.av...no=1&pgsize=50

"Too well lubricated?"!

Lack of lubricarion leads to:
-wear on the ball and socket, increasing clearances.
-difficulty getting the lock to properly latch.

As to the original statement (quoted), maybe the ball or socket were worn beyond limits, lubing removed some "crud" that was holding things together. This then allowed a "properly pinned/locked joint to come apart".
Go back to root cause, in my "non degreed mechanical engineering opinion".

IMHO, many things need to be cleaned, looked at, lubed a few times a year, at a good annual inspection at a minimum. Reducing wear and easing use of controls/systems are a benefit.

My mistake, very poor choice of phrasing. Lubricated with grease instead of something like graphite. Again this was relayed to be by another pilot. I currently fly a bird with automatic connections, still do a positive check, but occasional I fly in a two seat open so I would like to know.


On Friday, October 14, 2016 at 2:15:15 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
"Too well lubricated?"!

Lack of lubricarion leads to:
-wear on the ball and socket, increasing clearances.
-difficulty getting the lock to properly latch.

According to the NDSB report: "The pilot stated that during assembly of
the glider prior to the flight, the left aileron control tuve was
inadvertently not attached, anbd that he did not verify that all flight
controls moved free and correct prior to takeoff."

That doesn't sound to me like a failure of the L'Holelier fitting.


On 10/14/2016 9:27 AM, wrote:
On Thursday, October 13, 2016 at 7:44:07 PM UTC-4, Jonathan St. Cloud wrote:
Was it a pinned L'Hotelier that failed on the Nimbus 4M crash in Washington? Does anyone know of failures with properly pinned L'Hotelier?
http://www.ntsb.gov/_layouts/ntsb.av...no=1&pgsize=50


--
Dan, 5J

Of course the question was of L'Hotelier failures while correctly pinned.

On Friday, October 14, 2016 at 5:18:18 PM UTC-7, Dan Marotta wrote:
According to the NDSB report: "The pilot stated that during assembly of
the glider prior to the flight, the left aileron control tuve was
inadvertently not attached, anbd that he did not verify that all flight
controls moved free and correct prior to takeoff."

That doesn't sound to me like a failure of the L'Holelier fitting.

My previous comment/post still stands.

The glider under discussion may not allow this option but after buying my first ship (a DG-101)with L'Hotellier fittings, I quickly upgraded them with Wederkind sleeves. Very easy to use/lock. See http://aviation.derosaweb.net/wedekind/ for details.

L'Hotellier maintenance procedures from L'Hotellier Inc. can be found at; http://aviation.derosaweb.net/wedekind/documentation/L'Hotellier%20Maintenance%20IMA10_01-00.pdf. BTW: It recommends "grease", not graphite. I use http://www.super-lube.com/synthetic-...se-ezp-49.html.

John "OHM"

If the l'Hotellier head is not fastened to the ball, inserting the pin
won't make any difference. I was once advised to try to pull the
connector off the rod to make sure it really is on right.

It's often awkward and hard to see where the connectors are
fastened.

Once fastened and secured I like to move the rod while observing
the control surface.

The pins (or the other T/N and AD listed devices) can be put in place if the coupling is fully connected... or completely unconnected. On my 15 I can see the four L'Hotelliers quite well but I still first check that they're assembled properly by using the pull test and then carefully visually checking the connections. I then follow those up with a positive control check.

I have seen people get the couplings sort of "half-way connected": the wedge gets pushed down, the socket is put part way down the ball and then the wedge is released. In this situation the pins won't go in (or the Wedekinds won't slide home) so the few times I've seen it done it was always caught quickly.

One way I've theorized that the L'Hotelliers may have disconnected when not equipped with the safety devices would be if the spring loaded wedge got contaminated with enough dirt that the spring wasn't able to push it back up to lock the coupling when it was released after putting it over the ball.

At 00:11 13 October 2016, Dan Marotta wrote:
Those bobby pins are used extensively on my Stemme and I lost two
that
fell out of their retaining strings during taxiing operations leaving me
with only one spare. A quick search found 1.2 mm hitch pins at
WalMart
(of all places). I got a bag of 50 pins for under $8. Here's a link

for anyone needing the same. I've tried them and they fit.

--
Dan, 5J


I keep my pins in the strings with a small fly tying style thread wiping
and a drop of nail varnish.