Today's Message Index:
----------------------
1. 03:54 AM - Re: pitot system leaks (Carl Froehlich)
2. 07:09 AM - Re: Waiver for another pilot flying my plane (jfogarty tds.net)
3. 08:45 AM - Re: pitot system leaks (thomas sargent)
4. 09:08 AM - Re: pitot system leaks (Kelly McMullen)
Message 1
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| Subject: | Re: pitot system leaks |
The leak spec for the static system is to draw a vacuum to indicate 1000' ab
ove elevation and hold. The altimeter should not drop more than 100' in one
minute.
After chasing my tail to find a static leak on my 8A, I finally checked each
instrument separately with the panel on the bench. I found the face plate o
n the air speed indicator to be the source of the leak (the static port on t
he air speed indicator just connects to the case). To do this ASI leak test
, connect your manometer to a "T", then a line to both the pitot and static c
onnectors.
A simple field fix is to use a very small amount for RTV around the glass pe
rimeter. The more elaborate fix is to send it to an avionics shop - but tha
t will most likely be more expensive than just replacing the ASI.
Carl
On Jul 9, 2012, at 2:21 AM, vanremog@aol.com wrote:
>
> Are you sealing to the inside diameter of the tubing or the outside? Insi
de must mate with beaded or multi barbed fittings.
> Sorry, this should have been completed as: Outside must be absolutely fla
wless and slick to seal with O-ring fittings and a little DC4 couldn't hurt.
>
> -GV
>
>
> -----Original Message-----
> From: vanremog <vanremog@aol.com>
> To: rv-list <rv-list@matronics.com>
> Sent: Sun, Jul 8, 2012 11:18 pm
> Subject: Re: RV-List: pitot system leaks
>
> First of all, what types of fittings are you using? The best ones have in
timate sealing surfaces or ferrules.
> What is the nature of the sealing surfaces? They should be smooth and con
tiguous.
>
> Are you sealing to the inside diameter of the tubing or the outside? Insi
de must mate with beaded or multi barbed fittings.
>
> Are there threads in the potential leak path? If yes then use PST.
>
> -GV
>
>
>
>
> -----Original Message-----
> From: thomas sargent <sarg314@gmail.com>
> To: rv-list <rv-list@matronics.com>
> Sent: Sun, Jul 8, 2012 9:21 pm
> Subject: RV-List: pitot system leaks
>
> I tested the pitot system (using the water in a U-shaped tube method) in m
y RV-6A today and found it leaking fairly badly. Tightening up the various f
ittings helped. I'm always afraid of over-tightening those plastic fittings
. That improved things but it still leaks down the airspeed indicator from a
bout 106 to 100 knots in a couple of minutes. I assume it should be able to
hold constant for many minutes?
>
> Do people ever use any kind of sealant on these fittings? A thin film of o
il on the sealing surfaces perhaps?
>
> --
> Tom Sargent
>
>
> t=_blank>http://www.matronics.com/Navigator?RV-List
> p://forums.matronics.com
> blank>http://www.matronics.com/contribution
>
>
>
> t=_blank>http://www.matronics.com/Navigator?RV-List
> p://forums.matronics.com
> blank>http://www.matronics.com/contribution
>
>
>
==========================
=========
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=========
==========================
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>
Message 2
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| Subject: | Re: Waiver for another pilot flying my plane |
Joe, Call your agent and check on higher limits of liability insurance,
also, make sure they understand that it is someone other than you flying
off the first 40 hours. Also, check into an Umbrella policy through your
personal lines agent. Good luck.
Jim Fogarty
Breezy Point, MN
RV-9A building
On Sun, Jul 8, 2012 at 10:22 AM, JohnF <n29cx@ridgeviewtel.us> wrote:
> **
> Go to the AOPA web site...they have as fairly good one that you can
> download.
>
> ----- Original Message -----
> *From:* jconnell@fmwildblue.com
> *To:* RV-List <rv-list@matronics.com>
> *Sent:* Sunday, July 08, 2012 9:04 AM
> *Subject:* RV-List: Waiver for another pilot flying my plane
>
> Gentlemen:
>
> My RV-A is nearly ready for its first flight. I cannot medically fly the
> plane and another pilot(s) will be flying off the 40 hours.
>
> Do any of you have a waiver for other pilots to sign when they fly your
> RV? My wife and I are nervous about this...
>
> Thanks...
>
> Joe Connell
> Stewartville, MN
>
> *
>
> href="http://www.matronics.com/Navigator?RV-List">http://www.matronics.com/Navigator?RV-List
> href="http://forums.matronics.com">http://forums.matronics.com
> href="http://www.matronics.com/contribution">http://www.matronics.com/c*
>
> *
>
> *
>
>
Message 3
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| Subject: | Re: pitot system leaks |
The pitot system follows the plans. Van's pitot tube with aluminum fitting
to AL tubing which then mates to poly tubing which then connects to
instruments using nyloseal fittings. I could tighten many of the nyloseal
fittings with my fingers - so I did. I suspect the leaks are at the point
where the fittings screw into the instruments.
On Mon, Jul 9, 2012 at 3:51 AM, Carl Froehlich
<carl.froehlich@verizon.net>wrote:
> The leak spec for the static system is to draw a vacuum to indicate 1000'
> above elevation and hold. The altimeter should not drop more than 100' in
> one minute.
>
> After chasing my tail to find a static leak on my 8A, I finally checked
> each instrument separately with the panel on the bench. I found the face
> plate on the air speed indicator to be the source of the leak (the static
> port on the air speed indicator just connects to the case). To do this ASI
> leak test, connect your manometer to a "T", then a line to both the pitot
> and static connectors.
>
> A simple field fix is to use a very small amount for RTV around the glass
> perimeter. The more elaborate fix is to send it to an avionics shop - but
> that will most likely be more expensive than just replacing the ASI.
>
> Carl
>
> On Jul 9, 2012, at 2:21 AM, vanremog@aol.com wrote:
>
>
> Are you sealing to the inside diameter of the tubing or the outside?
> Inside must mate with beaded or multi barbed fittings.
>
> Sorry, this should have been completed as: Outside must be absolutely
> flawless and slick to seal with O-ring fittings and a little DC4 couldn't
> hurt.
>
> -GV
>
>
> -----Original Message-----
> From: vanremog <vanremog@aol.com>
> To: rv-list <rv-list@matronics.com>
> Sent: Sun, Jul 8, 2012 11:18 pm
> Subject: Re: RV-List: pitot system leaks
>
> First of all, what types of fittings are you using? The best ones have
> intimate sealing surfaces or ferrules.
> What is the nature of the sealing surfaces? They should be smooth and
> contiguous.
>
> Are you sealing to the inside diameter of the tubing or the outside?
> Inside must mate with beaded or multi barbed fittings.
>
> Are there threads in the potential leak path? If yes then use PST.
>
> -GV
>
>
> -----Original Message-----
> From: thomas sargent <sarg314@gmail.com>
> To: rv-list <rv-list@matronics.com>
> Sent: Sun, Jul 8, 2012 9:21 pm
> Subject: RV-List: pitot system leaks
>
> I tested the pitot system (using the water in a U-shaped tube method) in
> my RV-6A today and found it leaking fairly badly. Tightening up the
> various fittings helped. I'm always afraid of over-tightening those
> plastic fittings. That improved things but it still leaks down the
> airspeed indicator from about 106 to 100 knots in a couple of minutes. I
> assume it should be able to hold constant for many minutes?
>
> Do people ever use any kind of sealant on these fittings? A thin film of
> oil on the sealing surfaces perhaps?
>
> --
> Tom Sargent
>
> *
>
> t=_blank>http://www.matronics.com/Navigator?RV-List
> p://forums.matronics.com
> blank>http://www.matronics.com/contribution
> *
>
> *
>
> t=_blank>http://www.matronics.com/Navigator?RV-List
> p://forums.matronics.com
> blank>http://www.matronics.com/contribution
> *
>
> *
>
> ==================================
> /www.matronics.com/Navigator?RV-List
> ===================================cs.com
> ===================================matronics.com/contribution
> ==================================
> *
>
> *
>
> *
>
>
--
Tom Sargent
Message 4
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| Subject: | Re: pitot system leaks |
The pitot system does not need to be as leak free as the static system.
Small leaks have little effect on the airspeed indication. It operates
at very low pressure, a few inches of water. The static system is the
only one that needs to meet the standard below.
Kelly
On 7/9/2012 8:44 AM, thomas sargent wrote:
> The pitot system follows the plans. Van's pitot tube with aluminum
> fitting to AL tubing which then mates to poly tubing which then
> connects to instruments using nyloseal fittings. I could tighten many
> of the nyloseal fittings with my fingers - so I did. I suspect the
> leaks are at the point where the fittings screw into the instruments.
>
> On Mon, Jul 9, 2012 at 3:51 AM, Carl Froehlich
> <carl.froehlich@verizon.net <mailto:carl.froehlich@verizon.net>> wrote:
>
> The leak spec for the static system is to draw a vacuum to
> indicate 1000' above elevation and hold. The altimeter should not
> drop more than 100' in one minute.
>
> After chasing my tail to find a static leak on my 8A, I finally
> checked each instrument separately with the panel on the bench. I
> found the face plate on the air speed indicator to be the source
> of the leak (the static port on the air speed indicator just
> connects to the case). To do this ASI leak test, connect your
> manometer to a "T", then a line to both the pitot and static
> connectors.
>
> A simple field fix is to use a very small amount for RTV around
> the glass perimeter. The more elaborate fix is to send it to an
> avionics shop - but that will most likely be more expensive than
> just replacing the ASI.
>
> Carl
>
> On Jul 9, 2012, at 2:21 AM, vanremog@aol.com
> <mailto:vanremog@aol.com> wrote:
>
>>
>> Are you sealing to the inside diameter of the tubing or the
>> outside? Inside must mate with beaded or multi barbed fittings.
>>
>> Sorry, this should have been completed as: Outside must be
>> absolutely flawless and slick to seal with O-ring fittings and a
>> little DC4 couldn't hurt.
>> -GV
>>
>>
>> -----Original Message-----
>> From: vanremog <vanremog@aol.com <mailto:vanremog@aol.com>>
>> To: rv-list <rv-list@matronics.com <mailto:rv-list@matronics.com>>
>> Sent: Sun, Jul 8, 2012 11:18 pm
>> Subject: Re: RV-List: pitot system leaks
>>
>> First of all, what types of fittings are you using? The best
>> ones have intimate sealing surfaces or ferrules.
>> What is the nature of the sealing surfaces? They should be
>> smooth and contiguous.
>> Are you sealing to the inside diameter of the tubing or the
>> outside? Inside must mate with beaded or multi barbed fittings.
>> Are there threads in the potential leak path? If yes then use PST.
>> -GV
>>
>>
>> -----Original Message-----
>> From: thomas sargent <sarg314@gmail.com <mailto:sarg314@gmail.com>>
>> To: rv-list <rv-list@matronics.com <mailto:rv-list@matronics.com>>
>> Sent: Sun, Jul 8, 2012 9:21 pm
>> Subject: RV-List: pitot system leaks
>>
>> I tested the pitot system (using the water in a U-shaped tube
>> method) in my RV-6A today and found it leaking fairly badly.
>> Tightening up the various fittings helped. I'm always afraid of
>> over-tightening those plastic fittings. That improved things but
>> it still leaks down the airspeed indicator from about 106 to 100
>> knots in a couple of minutes. I assume it should be able to hold
>> constant for many minutes?
>>
>> Do people ever use any kind of sealant on these fittings? A thin
>> film of oil on the sealing surfaces perhaps?
>>
>> --
>> Tom Sargent
>> *
>>
>> t=_blank>http://www.matronics.com/Navigator?RV-List
>> p://forums.matronics.com <http://forums.matronics.com>
>> blank>http://www.matronics.com/contribution
>>
>> *
>> *
>>
>> t=_blank>http://www.matronics.com/Navigator?RV-List
>> p://forums.matronics.com <http://forums.matronics.com>
>> blank>http://www.matronics.com/contribution
>>
>> *
>> *
>>
>> =========
>> /www.matronics.com/Navigator?RV-List <http://www.matronics.com/Navigator?RV-List>
>> =========
>> cs.com <http://cs.com>
>> =========
>> matronics.com/contribution <http://matronics.com/contribution>
>> =========
>>
>> *
>
> *
>
> t="_blank">http://www.matronics.com/Navigator?RV-List
> tp://forums.matronics.com
> _blank">http://www.matronics.com/contribution
>
> *
>
>
> --
> Tom Sargent
> *
>
>
> *
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