Today's Message Index:
----------------------
1. 11:12 AM - Re: Nitrogen Loss (Jon)
2. 02:04 PM - Re: Nitrogen Loss (Anthony Royal)
3. 02:11 PM - Re: Nitrogen Loss (Jon)
4. 03:55 PM - Re: Nitrogen Loss (Anthony Royal)
Message 1
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| Subject: | Re: Nitrogen Loss |
Tony, can the canopy seals be patched like a bicycle tube?
Jon
On Mar 27, 2016 8:30 PM, "Anthony Royal" <skyking76t@verizon.net> wrote:
> Good idea Bill but if I can get the original part and bolt in, much easie
r
> and faster. I was lucky, found NOS part in CR.
>
> Anthony
>
>
> On Sunday, March 27, 2016 12:52 AM, Bill Geipel <l129bs@gmail.com> wrote:
>
>
> A schrader valve would prevent back flow.
>
> Sent from my iPad
>
> On Mar 27, 2016, at 08:08, Anthony Royal <skyking76t@verizon.net> wrote:
>
> I would be interested too!
>
> Found part of my leak problem.Removed the check valve that prevents
> nitrogen from the Nitro bottles from flowing back out of bottles. The fla
re
> on the check valve had a large burr,ridge on it. Not sure how that could
> have happened. Smoothed it out ( yes I know you can't really repair becau
se
> you alter the angle) and used some aircraft grade sealer made for sealing
a
> damaged flare and put back together for a test. Added 50 atm nitro last
> night and still had 20 atm left over 24 hours later and was stable. May
> leak at higher pressure but it is a start. Also removed the nitrogen tank
> purge/drain valve. Packing nut was still a little loose and it looked to
> have a little something on the sealing seat. When I first tried to tighte
n
> in the plane I got a significant increase in nitrogen pressure time. I'm
> working my way back toward the cockpit. Checked the 2 connections at the
> brake valve beside the stick. All seems to be very tight.
>
> Anybody have a new or good used check valve?
>
>
> On Saturday, March 26, 2016 2:32 AM, Bill Geipel <l129bs@gmail.com> wrote
:
>
>
> send description and pix.
>
> On Mar 25, 2016, at 20:36, Jean de Roubin <delfin29@me.com> wrote:
>
> I think the best way is an air compressor, working automatically at 20
> bars and stopping at 50.
> My, installed by the tzechs and approved by the factory is perfectly
> working since 15 years. No need of ground support.
> Jean de Roubin
>
> Envoy=C3=A9 de mon iPhone
>
> Le 25 mars 2016 =C3- 19:58, Frank Deeth <tr.9@westnet.com.au> a =C3=A9c
rit :
>
> Thanks Jorgen!
>
> Sent from my iPhone
>
> On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen <jorgen.nielsen@mweb.co.za>
> wrote:
>
> Mine is also done like that. I only posted half the story earlier,
> herewith then the full story J
>
> I don=99t use oxygen, so repurposed the tanks.
>
> My oxygen tanks have a tap on them, close to the bottles, and a pressure
> gauge. The tap & gauge is situated in the nose compartment.
> My normal air bottle (N2) also have a tap on them, and a gauge, also in
> the nose compartment.
> So far, 2 separate systems.
> After the taps, they are interconnected via a T, output goes to the air
> system.
>
> Benefits:
> Closing the valves means no leaks when she is standing.
> Having the 2 systems that close means I can go away for a weekend with no
> ground support, or for example a 3 hop ferry I did a while back. At the
> destination, close the active system. For the next flight, pick a system
> and open valve. When the system is empty use the next one.
>
> To fill, if its just a normal flight from home base, I open the valve for
> whichever system is in use, and fill normally. For extended flights, one
> can fill one system at a time, or open both and fill both, then close one
.
>
> So far, completely trouble free for a number of years.
>
> I will have to take some pics when at the airport. I used spare hand
> operated valves, similar to the pressure release inside the cockpit. I
> never did the work myself, I have a Russian guy who does all my
> maintenance, I just dreamt it up and asked him to do it.
>
> Another mod we did: my front / rear braking system has been reversed. I
> was once taxying with pax, and asked them to hold the brake while I did
> something. On release, when I took over, suddenly I had no brakes, and n
o
> steering obviously. We almost went farming. In normal ops, the rear bra
ke
> is for the instructor, and held a certain way can disable the front cabin
> system. Not good for how we operate them privately.
>
> Regards to all
> Jorgen
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Frank Deeth
> *Sent:* Friday, 25 March 2016 21:07
> *To:* l29-list@matronics.com
> *Subject:* Re: L29-List: Nitrogen Loss
>
> I read once about an L-29 being operated in the UK where they disconnecte
d
> the oxy system and plumbed those bottles into the pneumatic system, almos
t
> doubles the capacity if I recall...? Has anyone else looked at doing that
?
>
> Frank
>
> Sent from my iPad
>
> On Mar 26, 2016, at 4:20 AM, Bill Culberson <bculberson@staraviation.com>
> wrote:
>
> Ultrasonic leak detector only works on the high pressure leaks (75-100
> BAR), as it detects the specific audio signature of high pressure gas
> escaping. Canopy seals and brakes are at lower pressures and the soap and
> water test seems best.
>
> I don=99t use a Schrader valve but rather the original quarter turn
valve
> but recently converted the N2 Cover to having a Schrader adapter
=9Cjust in
> case=9D. My plane doesn=99t leak much but discovered that wit
h the cover
> changed and a good gasket the N2 cover that the N2 remains for weeks
> instead of days. Main check valve must be leaking.
>
> I like the Hand valve at the tanks, what did you use? Pics?
>
> Bill
> N39DE
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Jorgen Nielsen
> *Sent:* Friday, March 25, 2016 2:52 AM
> *To:* l29-list@matronics.com
> *Subject:* RE: L29-List: Nitrogen Loss
>
> I also tried an ultrasonic leak detector, got a very expensive version on
> trial for a week from a specialty supplier. Could not find anything usin
g
> it either. Soapy water is messy but seems to work best.
>
> My air system is modified, with a hand valve installed close to the
> bottles. When I am done flying, I shut it off. Also nice if using the L
29
> to go somewhere, turn it off after landing, turn it back on before flight
,
> no losses.
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Anthony Royal
> *Sent:* Friday, 25 March 2016 02:17
> *To:* l29-list@matronics.com
> *Subject:* Re: L29-List: Nitrogen Loss
>
> Hey guys,
> Thanks for all your suggestions! John, I did the soapy water test on
> every fitting I could find all the way back to the fittings for the
> emergency bottle and beyond. ...tightened too. No Joy.
>
> Bill, I think I did the top nut but missed the lower nut. I'll look at
> that next . Yeah, I'm 60 and a little too big to get into that small of
> quarters.
>
> Hey Frank, thanks for the info too!
>
> I'm also looking at disconnecting the the main pressurizing line line at
> the pressure reduction valve for the down stream items, after the nitroge
n
> bottles, and capping off the line and then pressurizing the bottles. This
> should tell me if there is a leak anywhere upstream of the reduction valv
e
> in the main charging system. The emergency bottle holds pressure perfectl
y
> so no problems there.
>
> According to the service manual, the minimum loss is 5 atm over 2 hours.
> So, I'm right on that limit at 2.5 atm per hour.
>
> Thanks!
> Tony
>
>
> On Thursday, March 24, 2016 7:15 PM, John Cabrera <jetblast1@me.com>
> wrote:
>
> I don=9Dt know if this is going to be of any help and some may laug
h at me
> but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic
> leak detector and could not find any leak. Finally decided to check with
> old fashion soapy water and a spray bottle. That worked.
>
> John
>
>
> On Mar 23, 2016, at 8:22 AM, Anthony Royal <skyking76t@verizon.net> wrote
:
>
> Guys, my L-29 has always held nitrogen for days without much loss of
> pressure. Other day I pressurized to 140 atm because of a long flight and
> day. Pressure bled off immediately from 140 to about 90 atm before I coul
d
> get out of the hangar. And was totally empty the next day. I found sever
al
> loose, original safety wired, connections not tight. Packing nut on the
> nitrogen purge valve was loose too. Tightened every fitting and thing I
> could find from nose to rear cockpit.
>
> Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I
> pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now.
> That's about 2.5 atm per hour. Any suggestions what else might cause suc
h
> a consistent leak? Thinking maybe the pressure relief valve leaking? Chec
k
> valve? Reading manuals and reviewing diagrams but thought maybe someone
> else may have run into this same problem and save a lot of time
>
> Someone, in a post I can't find, suggested an ultrasonic tester of some
> sort to detect high pressure leaks. Does anyone know which one it was?
>
> Also, looking for the glass lens for the taxi light. Rock must have hit
> mineand cracked it in half. Glued it back but would like to replacement.
> Also looking for connector to ARC EA-401A encoding altimeter.
>
> Thanks for any info
>
> Anthony
>
>
Message 2
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| Subject: | Re: Nitrogen Loss |
Jon, I don't know. I was thinking about that also. When I was in high schoo
l I worked in a tire shop and we patched tubes and also did what was called
"vulcanizing" of the fill valves to tractor tubes. The outside of the cano
py seal is ribbed so a patch probably won't work there. Might be worth a tr
y. If you can find the leak, might try using some of the patch glue and pul
l the split together and see if it would hold. Not a lot of pressure in the
seal.
Maybe we need to do like the guys did back in the 2000's with the engine oi
l and get orders from people who want them and everyone go together and get
a company to make a run of new front and rear canopy seals.=C2-
On Thursday, March 31, 2016 2:09 PM, Jon <jonairway@gmail.com> wrote:
Tony, can the canopy seals be patched like a bicycle tube?JonOn Mar 27, 20
16 8:30 PM, "Anthony Royal" <skyking76t@verizon.net> wrote:
Good idea Bill but if I can get the original part and bolt in, much easier
and faster.=C2- I was lucky, found NOS part in CR.
Anthony=C2-
On Sunday, March 27, 2016 12:52 AM, Bill Geipel <l129bs@gmail.com> wrot
e:
A schrader valve would prevent back flow.
Sent from my iPad
On Mar 27, 2016, at 08:08, Anthony Royal <skyking76t@verizon.net> wrote:
I would be interested too!
Found part of my leak problem.Removed the check valve that prevents nitroge
n from the Nitro bottles from flowing back out of bottles. The flare on the
check valve had a large burr,ridge on it. Not sure how that could have hap
pened. Smoothed it out ( yes I know you can't really repair because you alt
er the angle) and used some aircraft grade sealer made for sealing a damage
d flare and put back together for a test. Added 50 atm nitro last night and
still had 20 atm left over 24 hours later and was stable.=C2- May leak a
t higher pressure but it is a start. Also removed the nitrogen tank purge/d
rain valve. Packing nut was still a little loose and it looked to have a li
ttle something on the sealing seat. When I first tried to tighten in the pl
ane I got a significant increase in nitrogen pressure time. I'm working my
way back toward the cockpit.=C2- Checked the 2 connections at the brake v
alve beside the stick. All seems to be very tight.
Anybody have a new or good used check valve?=C2-
On Saturday, March 26, 2016 2:32 AM, Bill Geipel <l129bs@gmail.com> wro
te:
send description and pix.
On Mar 25, 2016, at 20:36, Jean de Roubin <delfin29@me.com> wrote:
I think the best way is an air compressor, working automatically at 20 bars
and stopping at 50.My, installed by the tzechs and approved by the factory
is perfectly working since 15 years. No need of ground support.Jean de Rou
bin
Envoy=C3=A9 de mon iPhone
Le 25 mars 2016 =C3- 19:58, Frank Deeth <tr.9@westnet.com.au> a =C3=A9cri
t=C2-:
Thanks Jorgen!
Sent from my iPhone
On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen <jorgen.nielsen@mweb.co.za> wrot
e:
Mine is also done like that.=C2- I only posted half the story earlier, he
rewith then the full story=C2-J=C2-I don=99t use oxygen, so repur
posed the tanks.=C2-=C2-My oxygen tanks have a tap on them, close to th
e bottles, and a pressure gauge.=C2- The tap & gauge is situated in the n
ose compartment.My normal air bottle (N2) also have a tap on them, and a ga
uge, also in the nose compartment.=C2-So far, 2 separate systems.After th
e taps, they are interconnected via a T, output goes to the air system.=C2
-Benefits:Closing the valves means no leaks when she is standing.Having t
he 2 systems that close means I can go away for a weekend with no ground su
pport, or for example a 3 hop ferry I did a while back.=C2- At the destin
ation, close the active system.=C2- For the next flight, pick a system an
d open valve.=C2- When the system is empty use the next one.=C2-To fill
, if its just a normal flight from home base, I open the valve for whicheve
r system is in use, and fill normally.=C2- For extended flights, one can
fill one system at a time, or open both and fill both, then close one.=C2
-So far, completely trouble free for a number of years.=C2-I will have
to take some pics when at the airport.=C2- I used spare hand operated val
ves, similar to the pressure release inside the cockpit.=C2- I never did
the work myself, I have a Russian guy who does all my maintenance, I just d
reamt it up and asked him to do it.=C2-Another mod we did:=C2- my front
/ rear braking system has been reversed.=C2- I was once taxying with pax
, and asked them to hold the brake while I did something.=C2- On release,
when I took over, suddenly I had no brakes, and no steering obviously.=C2
- We almost went farming.=C2- In normal ops, the rear brake is for the
instructor, and held a certain way can disable the front cabin system.=C2
- Not good for how we operate them privately. =C2-=C2-=C2-=C2-Reg
ards to allJorgen=C2-From:=C2-owner-l29-list-server@matronics.com=C2-
[mailto:owner-l29-list-server@matronics.com]=C2-On Behalf Of=C2-Frank D
eeth
Sent:=C2-Friday, 25 March 2016 21:07
To:=C2-l29-list@matronics.com
Subject:=C2-Re: L29-List: Nitrogen Loss =C2-I read once about an L-29 b
eing operated in the UK where they disconnected the oxy system and plumbed
those bottles into the pneumatic system, almost doubles the capacity if I r
ecall...? Has anyone else looked at doing that? =C2-Frank
Sent from my iPad
On Mar 26, 2016, at 4:20 AM, Bill Culberson <bculberson@staraviation.com> w
rote:
Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR)
, as it detects the specific audio signature of high pressure gas escaping.
Canopy seals and brakes are at lower pressures and the soap and water test
seems best.=C2-I don=99t use a Schrader valve but rather the origi
nal quarter turn valve but recently converted the N2 Cover to having a Schr
ader adapter =9Cjust in case=9D. My plane doesn=99t leak
much but discovered that with the cover changed and a good gasket the N2 co
ver that the N2 remains for weeks instead of days. Main check valve must be
leaking.=C2-I like the Hand valve at the tanks, what did you use? Pics?
=C2-BillN39DE=C2-From:=C2-owner-l29-list-server@matronics.com=C2-[m
ailto:owner-l29-list-server@matronics.com]=C2-On Behalf Of=C2-Jorgen Ni
elsen
Sent:=C2-Friday, March 25, 2016 2:52 AM
To:=C2-l29-list@matronics.com
Subject:=C2-RE: L29-List: Nitrogen Loss=C2-I also tried an ultrasonic l
eak detector, got a very expensive version on trial for a week from a speci
alty supplier.=C2- Could not find anything using it either.=C2- Soapy w
ater is messy but seems to work best.=C2-My air system is modified, with
a hand valve installed close to the bottles.=C2- When I am done flying, I
shut it off.=C2- Also nice if using the L29 to go somewhere, turn it off
after landing, turn it back on before flight, no losses.=C2-From:=C2-o
wner-l29-list-server@matronics.com=C2-[mailto:owner-l29-list-server@matro
nics.com]=C2-On Behalf Of=C2-Anthony Royal
Sent:=C2-Friday, 25 March 2016 02:17
To:=C2-l29-list@matronics.com
Subject:=C2-Re: L29-List: Nitrogen Loss=C2-Hey guys,Thanks for all your
suggestions!=C2- John, I did the soapy water test on every fitting I cou
ld find all the way back to the fittings for the emergency bottle and beyon
d. ...tightened too. No Joy.=C2-Bill, I think I did the top nut but misse
d the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big
to get into that small of quarters.=C2-Hey Frank, thanks for the info to
o!=C2-I'm also looking at disconnecting the the main pressurizing line li
ne at the pressure reduction valve for the down stream items, after the nit
rogen bottles, and capping off the line and then pressurizing the bottles.
This should tell me if there is a leak anywhere upstream of the reduction v
alve in the main charging system. The emergency bottle holds pressure perfe
ctly so no problems there.=C2-According to the service manual, the minimu
m loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per ho
ur.=C2-Thanks!Tony=C2-=C2-=C2-=C2-On Thursday, March 24, 2016 7:1
5 PM, John Cabrera <jetblast1@me.com> wrote:=C2-I don=9Dt know if t
his is going to be of any help and some may laugh at me but i was chasing a
t leak in the rear canopy.=C2- Bought a fancy ultrasonic leak detector an
d could not find any leak.=C2- Finally decided to check with old fashion
soapy water and a spray bottle.=C2- That worked. =C2-=C2-John=C2-
=C2-=C2-
On Mar 23, 2016, at 8:22 AM, Anthony Royal <skyking76t@verizon.net> wrote:
=C2-Guys, =C2-my L-29 has always held nitrogen for days without much lo
ss of pressure. Other day I pressurized to 140 atm because of a long flight
and day. Pressure bled off immediately from 140 to about 90 atm before I c
ould get out of the hangar.=C2- And was totally empty the next day. I fou
nd several loose, original safety wired, connections not tight. Packing nut
on the nitrogen purge valve was loose too. Tightened every fitting and thi
ng I could find from nose to rear cockpit. =C2-=C2-Now, if I pressurize
to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lo
se 30 atm in 12 hours. Very consistent now.=C2- That's about 2.5 atm per
hour.=C2- Any suggestions what else might cause such a consistent leak? T
hinking maybe the pressure relief valve leaking? Check valve?=C2- Reading
manuals and reviewing diagrams but thought maybe someone else may have run
into this same problem and save a lot of time=C2-Someone, in a post I ca
n't find, suggested an ultrasonic tester of some sort to detect high pressu
re leaks. Does anyone know which one it was?=C2-Also, looking for the gla
ss lens for the taxi light. Rock must have hit mineand cracked it in half.
Glued it back but would like to replacement.=C2- Also looking for connect
or to ARC EA-401A encoding altimeter.=C2-Thanks for any info=C2-Anthony
Message 3
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|
| Subject: | Re: Nitrogen Loss |
I'd be in..... I also am seeing an increased rate of NO2 loss. I'll start
tracing it when it warms up.
On Mar 31, 2016 5:05 PM, "Anthony Royal" <skyking76t@verizon.net> wrote:
> Jon, I don't know. I was thinking about that also. When I was in high
> school I worked in a tire shop and we patched tubes and also did what was
> called "vulcanizing" of the fill valves to tractor tubes. The outside of
> the canopy seal is ribbed so a patch probably won't work there. Might be
> worth a try. If you can find the leak, might try using some of the patch
> glue and pull the split together and see if it would hold. Not a lot of
> pressure in the seal.
>
> Maybe we need to do like the guys did back in the 2000's with the engine
> oil and get orders from people who want them and everyone go together and
> get a company to make a run of new front and rear canopy seals.
>
>
> On Thursday, March 31, 2016 2:09 PM, Jon <jonairway@gmail.com> wrote:
>
>
> Tony, can the canopy seals be patched like a bicycle tube?
> Jon
> On Mar 27, 2016 8:30 PM, "Anthony Royal" <skyking76t@verizon.net> wrote:
>
> Good idea Bill but if I can get the original part and bolt in, much easie
r
> and faster. I was lucky, found NOS part in CR.
>
> Anthony
>
>
> On Sunday, March 27, 2016 12:52 AM, Bill Geipel <l129bs@gmail.com> wrote:
>
>
> A schrader valve would prevent back flow.
>
> Sent from my iPad
>
> On Mar 27, 2016, at 08:08, Anthony Royal <skyking76t@verizon.net> wrote:
>
> I would be interested too!
>
> Found part of my leak problem.Removed the check valve that prevents
> nitrogen from the Nitro bottles from flowing back out of bottles. The fla
re
> on the check valve had a large burr,ridge on it. Not sure how that could
> have happened. Smoothed it out ( yes I know you can't really repair becau
se
> you alter the angle) and used some aircraft grade sealer made for sealing
a
> damaged flare and put back together for a test. Added 50 atm nitro last
> night and still had 20 atm left over 24 hours later and was stable. May
> leak at higher pressure but it is a start. Also removed the nitrogen tank
> purge/drain valve. Packing nut was still a little loose and it looked to
> have a little something on the sealing seat. When I first tried to tighte
n
> in the plane I got a significant increase in nitrogen pressure time. I'm
> working my way back toward the cockpit. Checked the 2 connections at the
> brake valve beside the stick. All seems to be very tight.
>
> Anybody have a new or good used check valve?
>
>
> On Saturday, March 26, 2016 2:32 AM, Bill Geipel <l129bs@gmail.com> wrote
:
>
>
> send description and pix.
>
> On Mar 25, 2016, at 20:36, Jean de Roubin <delfin29@me.com> wrote:
>
> I think the best way is an air compressor, working automatically at 20
> bars and stopping at 50.
> My, installed by the tzechs and approved by the factory is perfectly
> working since 15 years. No need of ground support.
> Jean de Roubin
>
> Envoy=C3=A9 de mon iPhone
>
> Le 25 mars 2016 =C3- 19:58, Frank Deeth <tr.9@westnet.com.au> a =C3=A9c
rit :
>
> Thanks Jorgen!
>
> Sent from my iPhone
>
> On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen <jorgen.nielsen@mweb.co.za>
> wrote:
>
> Mine is also done like that. I only posted half the story earlier,
> herewith then the full story J
>
> I don=99t use oxygen, so repurposed the tanks.
>
> My oxygen tanks have a tap on them, close to the bottles, and a pressure
> gauge. The tap & gauge is situated in the nose compartment.
> My normal air bottle (N2) also have a tap on them, and a gauge, also in
> the nose compartment.
> So far, 2 separate systems.
> After the taps, they are interconnected via a T, output goes to the air
> system.
>
> Benefits:
> Closing the valves means no leaks when she is standing.
> Having the 2 systems that close means I can go away for a weekend with no
> ground support, or for example a 3 hop ferry I did a while back. At the
> destination, close the active system. For the next flight, pick a system
> and open valve. When the system is empty use the next one.
>
> To fill, if its just a normal flight from home base, I open the valve for
> whichever system is in use, and fill normally. For extended flights, one
> can fill one system at a time, or open both and fill both, then close one
.
>
> So far, completely trouble free for a number of years.
>
> I will have to take some pics when at the airport. I used spare hand
> operated valves, similar to the pressure release inside the cockpit. I
> never did the work myself, I have a Russian guy who does all my
> maintenance, I just dreamt it up and asked him to do it.
>
> Another mod we did: my front / rear braking system has been reversed. I
> was once taxying with pax, and asked them to hold the brake while I did
> something. On release, when I took over, suddenly I had no brakes, and n
o
> steering obviously. We almost went farming. In normal ops, the rear bra
ke
> is for the instructor, and held a certain way can disable the front cabin
> system. Not good for how we operate them privately.
>
> Regards to all
> Jorgen
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Frank Deeth
> *Sent:* Friday, 25 March 2016 21:07
> *To:* l29-list@matronics.com
> *Subject:* Re: L29-List: Nitrogen Loss
>
> I read once about an L-29 being operated in the UK where they disconnecte
d
> the oxy system and plumbed those bottles into the pneumatic system, almos
t
> doubles the capacity if I recall...? Has anyone else looked at doing that
?
>
> Frank
>
> Sent from my iPad
>
> On Mar 26, 2016, at 4:20 AM, Bill Culberson <bculberson@staraviation.com>
> wrote:
>
> Ultrasonic leak detector only works on the high pressure leaks (75-100
> BAR), as it detects the specific audio signature of high pressure gas
> escaping. Canopy seals and brakes are at lower pressures and the soap and
> water test seems best.
>
> I don=99t use a Schrader valve but rather the original quarter turn
valve
> but recently converted the N2 Cover to having a Schrader adapter
=9Cjust in
> case=9D. My plane doesn=99t leak much but discovered that wit
h the cover
> changed and a good gasket the N2 cover that the N2 remains for weeks
> instead of days. Main check valve must be leaking.
>
> I like the Hand valve at the tanks, what did you use? Pics?
>
> Bill
> N39DE
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Jorgen Nielsen
> *Sent:* Friday, March 25, 2016 2:52 AM
> *To:* l29-list@matronics.com
> *Subject:* RE: L29-List: Nitrogen Loss
>
> I also tried an ultrasonic leak detector, got a very expensive version on
> trial for a week from a specialty supplier. Could not find anything usin
g
> it either. Soapy water is messy but seems to work best.
>
> My air system is modified, with a hand valve installed close to the
> bottles. When I am done flying, I shut it off. Also nice if using the L
29
> to go somewhere, turn it off after landing, turn it back on before flight
,
> no losses.
>
> *From:* owner-l29-list-server@matronics.com [
> mailto:owner-l29-list-server@matronics.com
> <owner-l29-list-server@matronics.com>] *On Behalf Of *Anthony Royal
> *Sent:* Friday, 25 March 2016 02:17
> *To:* l29-list@matronics.com
> *Subject:* Re: L29-List: Nitrogen Loss
>
> Hey guys,
> Thanks for all your suggestions! John, I did the soapy water test on
> every fitting I could find all the way back to the fittings for the
> emergency bottle and beyond. ...tightened too. No Joy.
>
> Bill, I think I did the top nut but missed the lower nut. I'll look at
> that next . Yeah, I'm 60 and a little too big to get into that small of
> quarters.
>
> Hey Frank, thanks for the info too!
>
> I'm also looking at disconnecting the the main pressurizing line line at
> the pressure reduction valve for the down stream items, after the nitroge
n
> bottles, and capping off the line and then pressurizing the bottles. This
> should tell me if there is a leak anywhere upstream of the reduction valv
e
> in the main charging system. The emergency bottle holds pressure perfectl
y
> so no problems there.
>
> According to the service manual, the minimum loss is 5 atm over 2 hours.
> So, I'm right on that limit at 2.5 atm per hour.
>
> Thanks!
> Tony
>
>
> On Thursday, March 24, 2016 7:15 PM, John Cabrera <jetblast1@me.com>
> wrote:
>
> I don=9Dt know if this is going to be of any help and some may laug
h at me
> but i was chasing at leak in the rear canopy. Bought a fancy ultrasonic
> leak detector and could not find any leak. Finally decided to check with
> old fashion soapy water and a spray bottle. That worked.
>
> John
>
>
> On Mar 23, 2016, at 8:22 AM, Anthony Royal <skyking76t@verizon.net> wrote
:
>
> Guys, my L-29 has always held nitrogen for days without much loss of
> pressure. Other day I pressurized to 140 atm because of a long flight and
> day. Pressure bled off immediately from 140 to about 90 atm before I coul
d
> get out of the hangar. And was totally empty the next day. I found sever
al
> loose, original safety wired, connections not tight. Packing nut on the
> nitrogen purge valve was loose too. Tightened every fitting and thing I
> could find from nose to rear cockpit.
>
> Now, if I pressurize to 50 atm, I will lose 30 atm in 12 hours. If I
> pressurize to 100 atm I lose 30 atm in 12 hours. Very consistent now.
> That's about 2.5 atm per hour. Any suggestions what else might cause suc
h
> a consistent leak? Thinking maybe the pressure relief valve leaking? Chec
k
> valve? Reading manuals and reviewing diagrams but thought maybe someone
> else may have run into this same problem and save a lot of time
>
> Someone, in a post I can't find, suggested an ultrasonic tester of some
> sort to detect high pressure leaks. Does anyone know which one it was?
>
> Also, looking for the glass lens for the taxi light. Rock must have hit
> mineand cracked it in half. Glued it back but would like to replacement.
> Also looking for connector to ARC EA-401A encoding altimeter.
>
> Thanks for any info
>
> Anthony
>
>
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| Subject: | Re: Nitrogen Loss |
Good luck. I've traced the entire main nitrogen system all the way back to
the front and rear brake valves (need to be double jointed and about 50 lbs
lighter) to the rear pressure gauge. Got the leak down to a constant 0.7 a
tm per hour or about 15 atm per 22 hours.=C2-
A Phd friend of mine suggested introducing a small amount of propane into t
he nitrogen system and then using a propane sniffer to find the problem. He
feels it's an inert enough gas with no moisture to use without any issues,
other than a little flammable, to trigger a sniffer at low pressures. I'm
leaning toward going that route.
On Thursday, March 31, 2016 5:14 PM, Jon <jonairway@gmail.com> wrote:
I'd be in..... I also am seeing an increased rate of NO2 loss. I'll start
tracing it when it warms up.On Mar 31, 2016 5:05 PM, "Anthony Royal" <skyki
ng76t@verizon.net> wrote:
Jon, I don't know. I was thinking about that also. When I was in high schoo
l I worked in a tire shop and we patched tubes and also did what was called
"vulcanizing" of the fill valves to tractor tubes. The outside of the cano
py seal is ribbed so a patch probably won't work there. Might be worth a tr
y. If you can find the leak, might try using some of the patch glue and pul
l the split together and see if it would hold. Not a lot of pressure in the
seal.
Maybe we need to do like the guys did back in the 2000's with the engine oi
l and get orders from people who want them and everyone go together and get
a company to make a run of new front and rear canopy seals.=C2-
On Thursday, March 31, 2016 2:09 PM, Jon <jonairway@gmail.com> wrote:
Tony, can the canopy seals be patched like a bicycle tube?JonOn Mar 27, 20
16 8:30 PM, "Anthony Royal" <skyking76t@verizon.net> wrote:
Good idea Bill but if I can get the original part and bolt in, much easier
and faster.=C2- I was lucky, found NOS part in CR.
Anthony=C2-
On Sunday, March 27, 2016 12:52 AM, Bill Geipel <l129bs@gmail.com> wrot
e:
A schrader valve would prevent back flow.
Sent from my iPad
On Mar 27, 2016, at 08:08, Anthony Royal <skyking76t@verizon.net> wrote:
I would be interested too!
Found part of my leak problem.Removed the check valve that prevents nitroge
n from the Nitro bottles from flowing back out of bottles. The flare on the
check valve had a large burr,ridge on it. Not sure how that could have hap
pened. Smoothed it out ( yes I know you can't really repair because you alt
er the angle) and used some aircraft grade sealer made for sealing a damage
d flare and put back together for a test. Added 50 atm nitro last night and
still had 20 atm left over 24 hours later and was stable.=C2- May leak a
t higher pressure but it is a start. Also removed the nitrogen tank purge/d
rain valve. Packing nut was still a little loose and it looked to have a li
ttle something on the sealing seat. When I first tried to tighten in the pl
ane I got a significant increase in nitrogen pressure time. I'm working my
way back toward the cockpit.=C2- Checked the 2 connections at the brake v
alve beside the stick. All seems to be very tight.
Anybody have a new or good used check valve?=C2-
On Saturday, March 26, 2016 2:32 AM, Bill Geipel <l129bs@gmail.com> wro
te:
send description and pix.
On Mar 25, 2016, at 20:36, Jean de Roubin <delfin29@me.com> wrote:
I think the best way is an air compressor, working automatically at 20 bars
and stopping at 50.My, installed by the tzechs and approved by the factory
is perfectly working since 15 years. No need of ground support.Jean de Rou
bin
Envoy=C3=A9 de mon iPhone
Le 25 mars 2016 =C3- 19:58, Frank Deeth <tr.9@westnet.com.au> a =C3=A9cri
t=C2-:
Thanks Jorgen!
Sent from my iPhone
On 26 Mar 2016, at 6:50 AM, Jorgen Nielsen <jorgen.nielsen@mweb.co.za> wrot
e:
Mine is also done like that.=C2- I only posted half the story earlier, he
rewith then the full story=C2-J=C2-I don=99t use oxygen, so repur
posed the tanks.=C2-=C2-My oxygen tanks have a tap on them, close to th
e bottles, and a pressure gauge.=C2- The tap & gauge is situated in the n
ose compartment.My normal air bottle (N2) also have a tap on them, and a ga
uge, also in the nose compartment.=C2-So far, 2 separate systems.After th
e taps, they are interconnected via a T, output goes to the air system.=C2
-Benefits:Closing the valves means no leaks when she is standing.Having t
he 2 systems that close means I can go away for a weekend with no ground su
pport, or for example a 3 hop ferry I did a while back.=C2- At the destin
ation, close the active system.=C2- For the next flight, pick a system an
d open valve.=C2- When the system is empty use the next one.=C2-To fill
, if its just a normal flight from home base, I open the valve for whicheve
r system is in use, and fill normally.=C2- For extended flights, one can
fill one system at a time, or open both and fill both, then close one.=C2
-So far, completely trouble free for a number of years.=C2-I will have
to take some pics when at the airport.=C2- I used spare hand operated val
ves, similar to the pressure release inside the cockpit.=C2- I never did
the work myself, I have a Russian guy who does all my maintenance, I just d
reamt it up and asked him to do it.=C2-Another mod we did:=C2- my front
/ rear braking system has been reversed.=C2- I was once taxying with pax
, and asked them to hold the brake while I did something.=C2- On release,
when I took over, suddenly I had no brakes, and no steering obviously.=C2
- We almost went farming.=C2- In normal ops, the rear brake is for the
instructor, and held a certain way can disable the front cabin system.=C2
- Not good for how we operate them privately. =C2-=C2-=C2-=C2-Reg
ards to allJorgen=C2-From:=C2-owner-l29-list-server@matronics.com=C2-
[mailto:owner-l29-list-server@matronics.com]=C2-On Behalf Of=C2-Frank D
eeth
Sent:=C2-Friday, 25 March 2016 21:07
To:=C2-l29-list@matronics.com
Subject:=C2-Re: L29-List: Nitrogen Loss =C2-I read once about an L-29 b
eing operated in the UK where they disconnected the oxy system and plumbed
those bottles into the pneumatic system, almost doubles the capacity if I r
ecall...? Has anyone else looked at doing that? =C2-Frank
Sent from my iPad
On Mar 26, 2016, at 4:20 AM, Bill Culberson <bculberson@staraviation.com> w
rote:
Ultrasonic leak detector only works on the high pressure leaks (75-100 BAR)
, as it detects the specific audio signature of high pressure gas escaping.
Canopy seals and brakes are at lower pressures and the soap and water test
seems best.=C2-I don=99t use a Schrader valve but rather the origi
nal quarter turn valve but recently converted the N2 Cover to having a Schr
ader adapter =9Cjust in case=9D. My plane doesn=99t leak
much but discovered that with the cover changed and a good gasket the N2 co
ver that the N2 remains for weeks instead of days. Main check valve must be
leaking.=C2-I like the Hand valve at the tanks, what did you use? Pics?
=C2-BillN39DE=C2-From:=C2-owner-l29-list-server@matronics.com=C2-[m
ailto:owner-l29-list-server@matronics.com]=C2-On Behalf Of=C2-Jorgen Ni
elsen
Sent:=C2-Friday, March 25, 2016 2:52 AM
To:=C2-l29-list@matronics.com
Subject:=C2-RE: L29-List: Nitrogen Loss=C2-I also tried an ultrasonic l
eak detector, got a very expensive version on trial for a week from a speci
alty supplier.=C2- Could not find anything using it either.=C2- Soapy w
ater is messy but seems to work best.=C2-My air system is modified, with
a hand valve installed close to the bottles.=C2- When I am done flying, I
shut it off.=C2- Also nice if using the L29 to go somewhere, turn it off
after landing, turn it back on before flight, no losses.=C2-From:=C2-o
wner-l29-list-server@matronics.com=C2-[mailto:owner-l29-list-server@matro
nics.com]=C2-On Behalf Of=C2-Anthony Royal
Sent:=C2-Friday, 25 March 2016 02:17
To:=C2-l29-list@matronics.com
Subject:=C2-Re: L29-List: Nitrogen Loss=C2-Hey guys,Thanks for all your
suggestions!=C2- John, I did the soapy water test on every fitting I cou
ld find all the way back to the fittings for the emergency bottle and beyon
d. ...tightened too. No Joy.=C2-Bill, I think I did the top nut but misse
d the lower nut. I'll look at that next . Yeah, I'm 60 and a little too big
to get into that small of quarters.=C2-Hey Frank, thanks for the info to
o!=C2-I'm also looking at disconnecting the the main pressurizing line li
ne at the pressure reduction valve for the down stream items, after the nit
rogen bottles, and capping off the line and then pressurizing the bottles.
This should tell me if there is a leak anywhere upstream of the reduction v
alve in the main charging system. The emergency bottle holds pressure perfe
ctly so no problems there.=C2-According to the service manual, the minimu
m loss is 5 atm over 2 hours. So, I'm right on that limit at 2.5 atm per ho
ur.=C2-Thanks!Tony=C2-=C2-=C2-=C2-On Thursday, March 24, 2016 7:1
5 PM, John Cabrera <jetblast1@me.com> wrote:=C2-I don=9Dt know if t
his is going to be of any help and some may laugh at me but i was chasing a
t leak in the rear canopy.=C2- Bought a fancy ultrasonic leak detector an
d could not find any leak.=C2- Finally decided to check with old fashion
soapy water and a spray bottle.=C2- That worked. =C2-=C2-John=C2-
=C2-=C2-
On Mar 23, 2016, at 8:22 AM, Anthony Royal <skyking76t@verizon.net> wrote:
=C2-Guys, =C2-my L-29 has always held nitrogen for days without much lo
ss of pressure. Other day I pressurized to 140 atm because of a long flight
and day. Pressure bled off immediately from 140 to about 90 atm before I c
ould get out of the hangar.=C2- And was totally empty the next day. I fou
nd several loose, original safety wired, connections not tight. Packing nut
on the nitrogen purge valve was loose too. Tightened every fitting and thi
ng I could find from nose to rear cockpit. =C2-=C2-Now, if I pressurize
to 50 atm, I will lose 30 atm in 12 hours. If I pressurize to 100 atm I lo
se 30 atm in 12 hours. Very consistent now.=C2- That's about 2.5 atm per
hour.=C2- Any suggestions what else might cause such a consistent leak? T
hinking maybe the pressure relief valve leaking? Check valve?=C2- Reading
manuals and reviewing diagrams but thought maybe someone else may have run
into this same problem and save a lot of time=C2-Someone, in a post I ca
n't find, suggested an ultrasonic tester of some sort to detect high pressu
re leaks. Does anyone know which one it was?=C2-Also, looking for the gla
ss lens for the taxi light. Rock must have hit mineand cracked it in half.
Glued it back but would like to replacement.=C2- Also looking for connect
or to ARC EA-401A encoding altimeter.=C2-Thanks for any info=C2-Anthony
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