Today's Message Index:
----------------------
1. 04:22 AM - Re: Fuel leaking from throat of M14P Carburettor (Dale)
2. 05:43 AM - Re: Re: helmets (Noise) (Rico Jaeger)
3. 06:56 AM - Re: Re: Fuel leaking from throat of M14P Carburettor (RICHARD VOLKER)
4. 08:00 AM - Re: Re: helmets (Noise) (Roger Kemp M.D.)
5. 08:05 AM - Re: Re: helmets (Noise) (Roger Kemp M.D.)
6. 08:08 AM - M14P primer nozzle (Joe Howse)
7. 08:57 AM - Re: M14P primer nozzle (Didier Blouzard)
8. 09:45 AM - Re: Uneven fuel feed CJ6 (barryhancock)
9. 10:37 AM - Re: M14P primer nozzle (Joe Howse)
10. 12:49 PM - Re: M14P primer nozzle (Didier Blouzard)
11. 01:11 PM - Re: Re: Uneven fuel feed CJ6 (Byron Fox)
12. 01:32 PM - Re: Re: Uneven fuel feed CJ6 (Larry Pine)
13. 01:45 PM - Re: Re: Uneven fuel feed CJ6 (Javier Carrasco)
14. 02:04 PM - Re: Re: helmets (Noise) (Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E)
15. 02:24 PM - Re: Re: Uneven fuel feed CJ6 (Gill Gutierrez)
16. 03:44 PM - Re: Re: Uneven fuel feed CJ6 (Brian Lloyd)
17. 05:40 PM - Practical aspects of Exhibition category (Ted Waltman)
18. 06:10 PM - Re: Practical aspects of Exhibition category (Roger Kemp M.D.)
19. 06:34 PM - Re: Practical aspects of Exhibition category (Richard Hess)
20. 06:34 PM - Re: Practical aspects of Exhibition category (Bill Geipel)
21. 07:12 PM - Re: Practical aspects of Exhibition category (george coy)
22. 08:47 PM - Re: Re: Uneven fuel feed CJ6 (Walter Lannon)
23. 09:28 PM - Re: Re: Uneven fuel feed CJ6 (Walter Lannon)
24. 10:19 PM - Re: Re: Uneven fuel feed CJ6 (Dave Laird)
Message 1
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| Subject: | Re: Fuel leaking from throat of M14P Carburettor |
Try tightening the bolts on the diaphram. You could also have a corroded orface
in diaphram port or a defective diaphram. Most likely one of these. Fuel
issues with diaphram will cause fuel to leak out the ram air sensor tubes located
around the inlet of the carb venturi.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=362914#362914
Message 2
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| Subject: | Re: helmets (Noise) |
'Anyone got an extra / used helmet they'd be willing to part w/? Thanks!!
>>> John Fischer <fish@aviation-tech.com> 1/9/2012 8:02 PM >>>
Nels,
Yes you can modify it relatively easy.
I purchased a civilian mike & earphones form Gibson/Barnes, then a
converter that plugged into the single plug to two plugs.
Works great.
Laterrrrr
John Fischer
On 1/9/2012 1:11 PM, Nelson Sprague wrote:
> --> Yak-List message posted by: Nelson Sprague<nelsprague@hotmail.com>
>
> Brian I have my jet helmet from my air force days can I modify it for
use in the yak? Nels
>
> Brian Lloyd<brian@lloyd.com> wrote:
>
>
>> On Mon, Jan 9, 2012 at 8:20 AM, Herb Coussons<drc@wscare.com> wrote:
>>
>>
>>> For clarification-
>>> Is the Westone molded earpiece a com speaker?
>>>
>>>
>> Yes.
>>
>>
>>
>>> Or just an earplug utilizing the existing coms of the helmet?
>>>
>>>
>> No.
>>
>>
>>
>>> It appears the CEP option is an in the ear com device that connects to
the
>>> helmet coms, bypassing the earcup coms already installed?
>>>
>>>
>> Not bypassing them. They are in parallel. You don't disable the stock
>> earspeakers so the helment/headset will continue to work normally
without
>> the CEP earpieces plugged in.
>>
>> --
>> Brian Lloyd, WB6RQN/J79BPL
>> 3191 Western Dr.
>> Cameron Park, CA 95682
>> brian@lloyd.com
>> +1.767.617.1365 (Dominica)
>> +1.916.877.5067 (USA)
>>
>
>
>
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| Subject: | Re: Fuel leaking from throat of M14P Carburettor |
Dale,
What is your correct e-mail address? I have an offline question for you.
Rick VOLKER
Sent from my iPhone
On Jan 10, 2012, at 7:19 AM, "Dale" <hdinamic@qwest.net> wrote:
>
> Try tightening the bolts on the diaphram. You could also have a corroded orface
in diaphram port or a defective diaphram. Most likely one of these. Fuel
issues with diaphram will cause fuel to leak out the ram air sensor tubes located
around the inlet of the carb venturi.
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=362914#362914
>
>
>
>
>
>
>
>
>
>
Message 4
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| Subject: | Re: helmets (Noise) |
Ah, nothing like blunt dissection!
Doc
Sent from my iPad
On Jan 9, 2012, at 4:54 PM, Dr Andres Katz <bu131@swbell.net> wrote:
> nothing a well trained flexum digitorum longus couldn't handle
>
>
>
> From: Roger Kemp MD <viperdoc@mindspring.com>
> To: yak-list@matronics.com
> Sent: Mon, January 9, 2012 4:00:58 PM
> Subject: RE: Yak-List: Re: helmets (Noise)
>
> Roge increased volume of the canal with increased number of vibri
ssae per mm of canal length along with the increased volume of the mass of d
esiccated mucous means increased resistance to flow. It really becomes a hug
e buggar to extract then! ( AKA The Woolley Booger)
> Doc
>
> From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@ma
tronics.com] On Behalf Of cjpilot710@aol.com
> Sent: Monday, January 09, 2012 2:55 PM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Re: helmets (Noise)
>
> Doc,
> Would extended length of the nasopharynx have an effect?
> Pappy
>
> In a message dated 1/9/2012 2:24:43 P.M. Eastern Standard Time, viperdoc@m
indspring.com writes:
> Pappy,
> Vibrissae and desiccated mucus in the nasopharynx will most definitely de
crease O2 flow through the nose. (aka Buggars). I know you knew that.
> ;^O))
> Doc
>
> From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@ma
tronics.com] On Behalf Of cjpilot710@aol.com
> Sent: Monday, January 09, 2012 11:28 AM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Re: helmets (Noise)
>
> OMG! Next we'll start talking about nose hair and its interference with o
xygen flow!!!
> Pappy
>
> In a message dated 1/9/2012 11:43:18 A.M. Eastern Standard Time, brian@llo
yd.com writes:
>
>
> On Mon, Jan 9, 2012 at 8:14 AM, Warren Hill <k7wx@earthlink.net> wrote:
>
> Brian,
>
> The Communications & Ear Protection system is what I had before the Weston
e system. Did not like it very much. Still had difficulty hearing the radio.
It was touted as having superior noise reduction, but I found it lacking in
many ways at the noise levels we experience in the CJ. My Lightseed noise r
eduction headset did a much better job, but would not allow me to wear a hel
met.
>
> Ear hair? You know, as we get older that damed ear hair gets tougher and c
an keep the expanding foam earpiece from sealing in the ear canal. I am gues
sing that it may be different for different people.
>
> One way to find out is if silicone foam earplugs work. If they do, then th
e CEP earphones should work too.
>
> --
> Brian Lloyd, WB6RQN/J79BPL
> 3191 Western Dr.
> Cameron Park, CA 95682
> brian@lloyd.com
> +1.767.617.1365 (Dominica)
> +1.916.877.5067 (USA)
>
>
>
> ="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/
Navigator?Yak-List
> s.matronics.com/">http://forums.matronics.com
> p://www.matronics.com/contribution">http://www.matronics.com/contribution
>
>
>
> http://www.matronics.com/Navigator?Yak-List
> http://forums.matronics.com
> http://www.matronics.com/contribution
>
>
>
>
> ="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.com/
Navigator?Yak-List
> s.matronics.com/">http://forums.matronics.com
> p://www.matronics.com/contribution">http://www.matronics.com/contribution
>
>
>
>
> http://www.matronics.com/Navigator?Yak-List
> http://forums.matronics.com
> http://www.matronics.com/contribution
>
> http://www.matronics.com/c================
>
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
Message 5
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| Subject: | Re: helmets (Noise) |
I have that adapter also to use with my current helmet. It is a bit weighty and
unruly under G.
Doc
Sent from my iPad
On Jan 9, 2012, at 4:29 PM, "Bitterlich, Mark G CIV Det Cherry Point, MALS-14 64E"
<mark.bitterlich@navy.mil> wrote:
>
> Gibson-Barnes also has an adapter cable. Assuming you have the standard U-174
connector on the end of your military helmet, you can take out any pre-amp module
that might have been in the O2 mask, and using the stock mike and earpieces,
the adapter cable will match the impedances and you can use it with the original
earpieces and microphone element. It converts the U-174 connector to
what is usually used in general aviation, which is the mono headphone male connector,
and the standard mike plug.. the nomenclature of which I forget! Sorry.
>
> Anyway, I've tried it, it works.... but I'd recommend doing what the folks below
are talking about versus this. Just letting you know it's there.
>
> Mark
>
>
> -----Original Message-----
> From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Roger Kemp MD
> Sent: Monday, January 09, 2012 5:16 PM
> To: yak-list@matronics.com
> Subject: RE: Yak-List: Re: helmets (Noise)
>
>
> Roger...sigtronics makes a nice mic attachment as well as ear phones. I did my original HGU 55 that way about 10 years ago. Not near the hanger so do not have the parts lists. If you still have your O2 mask, the sigtronics Lectric mic will mount directly in. You need to get the general aviation OHM' d (forgot the exact Ohms- 5?) ear phones. Go to www.gibson-barnes.com and click on helmet communication for the parts you need. They even have the bayonet clip that you can mount you boom mic on and use the bayonet receiver on your helmet without drilling holes in your helmet for the boom mic mount.
> Doc
>
> -----Original Message-----
> From: owner-yak-list-server@matronics.com [mailto:owner-yak-list-server@matronics.com] On Behalf Of Nelson Sprague
> Sent: Monday, January 09, 2012 3:11 PM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Re: helmets (Noise)
>
>
> Brian I have my jet helmet from my air force days can I modify it for use in
the yak? Nels
>
> Brian Lloyd <brian@lloyd.com> wrote:
>
>> On Mon, Jan 9, 2012 at 8:20 AM, Herb Coussons <drc@wscare.com> wrote:
>>
>>> For clarification-
>>> Is the Westone molded earpiece a com speaker?
>>>
>>
>> Yes.
>>
>>
>>> Or just an earplug utilizing the existing coms of the helmet?
>>>
>>
>> No.
>>
>>
>>> It appears the CEP option is an in the ear com device that connects
>>> to the helmet coms, bypassing the earcup coms already installed?
>>>
>>
>> Not bypassing them. They are in parallel. You don't disable the stock
>> earspeakers so the helment/headset will continue to work normally
>> without the CEP earpieces plugged in.
>>
>> --
>> Brian Lloyd, WB6RQN/J79BPL
>> 3191 Western Dr.
>> Cameron Park, CA 95682
>> brian@lloyd.com
>> +1.767.617.1365 (Dominica)
>> +1.916.877.5067 (USA)
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
Message 6
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| Subject: | M14P primer nozzle |
We had the same problem with our 18t but were able to remove the primer
nozzle,soaked it in brake cleaner then blew it out with high pressure
air.
Joe
Message 7
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| Subject: | Re: M14P primer nozzle |
Hello
I think I am starting to have same kind of problem on my 18T.
Is it difficult to remove the nozzle?.
Would you have pics???
I just come out of repairing my compressor on my 18T.
Not very difficult but on six bolts five come out in let say 20mn and the
last one is not difficult to remove but a nightmare to put back.
I would not like to start another .... difficult operation right now, just
if it is not too difficult I would like to check it out.
Best regards
Didier
2012/1/10 Joe Howse <joeh@shaw.ca>
> **
> We had the same problem with our 18t but were able to remove the primer
> nozzle,soaked it in brake cleaner then blew it out with high pressure air.
>
> Joe
>
> *
>
> *
>
>
--
____________________________
Didier BLOUZARD
Portable : +33 6 24 24 36 72
Email: didier.blouzard@gmail.com <didier.blouzard@anolistech.fr>
Message 8
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| Subject: | Re: Uneven fuel feed CJ6 |
3 axis electric trim. Independent fuel vents for left and right tanks. While you're
at it may as well do a ground up restoration. ;). The above is what I have
on my aircraft and the fuel imbalance problem is solved. I realize that's not
a workable solutiion for everyone, however. A fuel selector valve would be
great if someone would engineer that. Blackwell's vent switch system seems to
work, also. Other than that, get used to flying sideways for awhile....
Happy Skidding,
Barry
--------
Barry Hancock
Worldwide Warbirds, Inc.
(877) 869-6458
www.worldwidewarbirds.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=362945#362945
Message 9
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| Subject: | Re: M14P primer nozzle |
Didier
No pics, sorry, but very difficult to remove because of location and the
nozzle itself was very tight.
We used a 6 point socket and made up a short bar to turn the socket.
good luck
Joe
Message 10
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| Subject: | Re: M14P primer nozzle |
OK
Thanks very much
If this is it then we'll do it....
That's the price.
Thanks very much and best regards
Fly safe
Didier
2012/1/10 Joe Howse <joeh@shaw.ca>
> **
> Didier
>
> No pics, sorry, but very difficult to remove because of location and the
> nozzle itself was very tight.
>
> We used a 6 point socket and made up a short bar to turn the socket.
>
> good luck
>
> Joe
>
> *
>
> *
>
>
--
____________________________
Didier BLOUZARD
Portable : +33 6 24 24 36 72
Email: didier.blouzard@gmail.com <didier.blouzard@anolistech.fr>
Message 11
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| Subject: | Re: Uneven fuel feed CJ6 |
While still on this subject, a word of caution. *Do as I say, not as I did.*
*
*
I installed Bill Blackwell's fuel vent control system about 6 years ago.
And, as mentioned, it works well. Care, however, must be taken *not* to
leave a vent closed for too long. Our CJ fuel tanks are made of light
weight aluminum, and will collapse. Shortly after installing the system, I
forgot to open the left tank vent and landed. At the gas pump, I was
startled when I had to pull the left gas cap off to overcome the vacuum in
the tank. The consequent oil-canning noise really got my attention as air
rushed back into the tank.
OK, a new procedure -- cycle the vent switch every 5 minutes when balancing
the fuel tanks.
I thought I had dodged the bullet, but 6 years hence the left tank
developed a leak 3 weeks ago. Sure enough, the outboard end of my old tank
had collapsed inward a bit, making it concave instead of convex. Adjacent
to the grounding strap tab welded to the end of the tank a crack had
developed. The good news is that Doug Sapp had a new tank in stock.
So, either buy fuel bladders to replace the aluminum tanks, or *cycle the
vent switches very, very frequently.*
*
*
...Blitz
On Tue, Jan 10, 2012 at 9:41 AM, barryhancock <
bhancock@worldwidewarbirds.com> wrote:
> bhancock@worldwidewarbirds.com>
>
> 3 axis electric trim. Independent fuel vents for left and right tanks.
> While you're at it may as well do a ground up restoration. ;). The above
> is what I have on my aircraft and the fuel imbalance problem is solved. I
> realize that's not a workable solutiion for everyone, however. A fuel
> selector valve would be great if someone would engineer that. Blackwell's
> vent switch system seems to work, also. Other than that, get used to
> flying sideways for awhile....
>
> Happy Skidding,
>
> Barry
>
> --------
> Barry Hancock
> Worldwide Warbirds, Inc.
> (877) 869-6458
> www.worldwidewarbirds.com
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=362945#362945
>
>
--
... Blitz
Byron M. Fox
80 Milland Drive
Mill Valley, CA 94941
415-307-2405
Message 12
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| Subject: | Re: Uneven fuel feed CJ6 |
Ken worth trucks makes a pneumatic/electrical toggle switch that allows you
to add a panel light to indicate when these vents are closed.- This will
allow you to know or remind you that a vent is closed.- I have seen a CJ
with bladders flame out when the cell completely collapsed. - Just a lit
tle trick that adds safety.
Larry Pine
--- On Tue, 1/10/12, Byron Fox <byronmfox@gmail.com> wrote:
From: Byron Fox <byronmfox@gmail.com>
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
While still on this subject, a word of caution. Do as I say, not as I did.
I installed Bill Blackwell's fuel vent control system about 6 years ago. An
d, as mentioned, it works well. Care, however, must be taken not-to leave
a vent closed for too long. Our CJ fuel tanks are made of light weight alu
minum, and will collapse. Shortly after installing the system, I forgot to
open the left tank vent and landed. At the gas pump, I was startled when I
had to pull the left gas cap off to overcome the vacuum in the tank. The co
nsequent oil-canning noise really got my attention as air rushed back into
the tank.=0A
OK, a new procedure -- cycle the vent switch every 5 minutes when balancing
the fuel tanks.
I thought I had dodged the bullet, but 6 years hence the left tank develope
d a leak 3 weeks ago. -Sure enough, the outboard end of my old tank had c
ollapsed inward a bit, making it concave instead of convex. Adjacent to the
grounding strap tab welded to the end of the tank a crack had developed. T
he good news is that Doug Sapp had a new tank in stock.=0A
So, either buy fuel bladders to replace the aluminum tanks, or cycle the ve
nt switches very, very frequently.
...Blitz
On Tue, Jan 10, 2012 at 9:41 AM, barryhancock <bhancock@worldwidewarbirds.c
om> wrote:
ds.com>
=0A=0A
=0A3 axis electric trim. Independent fuel vents for left and right tanks. W
hile you're at it may as well do a ground up restoration. -;). The above
is what I have on my aircraft and the fuel imbalance problem is solved. I r
ealize that's not a workable solutiion for everyone, however. -A fuel sel
ector valve would be great if someone would engineer that. -Blackwell's v
ent switch system seems to work, also. -Other than that, get used to flyi
ng sideways for awhile....
=0A=0A
=0AHappy Skidding,
=0A
=0ABarry
=0A
=0A--------
=0ABarry Hancock
=0AWorldwide Warbirds, Inc.
=0A(877) 869-6458
=0Awww.worldwidewarbirds.com
=0A
=0A
=0A
=0A
=0ARead this topic online here:
=0A
=0Ahttp://forums.matronics.com/viewtopic.php?p=362945#362945
=0A
=0A
=0A
=0A
=0A
=0A
=0A
=0A==========
=0Arget="_blank">http://www.matronics.com/Navigator?Yak-List
=0A==========
=0Ahttp://forums.matronics.com
=0A==========
=0Ale, List Admin.
=0A="_blank">http://www.matronics.com/contribution
=0A==========
=0A
=0A
=0A
=0A
--
... Blitz
Byron M. Fox80 Milland DriveMill Valley, CA 94941415-307-2405
=0A
=0A=0A=0A
Message 13
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| Subject: | Re: Uneven fuel feed CJ6 |
Also Check your-tank caps,
-
My '55 uneven fuel consumption aggravated once the rubber seal in on of the
caps came too lose, I switched the tank caps and I can see the transfer is
sue switch to the-other tank. Recently I had both caps refitted and we ar
e back to the normal "unbalance".
-
It seems that the tank on the side that had the good cap was the one runnin
g lower on gas always, switching the caps and the problem switched sides.
-
JC
--- On Tue, 1/10/12, Byron Fox <byronmfox@gmail.com> wrote:
From: Byron Fox <byronmfox@gmail.com>
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
While still on this subject, a word of caution. Do as I say, not as I did.
I installed Bill Blackwell's fuel vent control system about 6 years ago. An
d, as mentioned, it works well. Care, however, must be taken not-to leave
a vent closed for too long. Our CJ fuel tanks are made of light weight alu
minum, and will collapse. Shortly after installing the system, I forgot to
open the left tank vent and landed. At the gas pump, I was startled when I
had to pull the left gas cap off to overcome the vacuum in the tank. The co
nsequent oil-canning noise really got my attention as air rushed back into
the tank.
OK, a new procedure -- cycle the vent switch every 5 minutes when balancing
the fuel tanks.
I thought I had dodged the bullet, but 6 years hence the left tank develope
d a leak 3 weeks ago. -Sure enough, the outboard end of my old tank had c
ollapsed inward a bit, making it concave instead of convex. Adjacent to the
grounding strap tab welded to the end of the tank a crack had developed. T
he good news is that Doug Sapp had a new tank in stock.
So, either buy fuel bladders to replace the aluminum tanks, or cycle the ve
nt switches very, very frequently.
...Blitz
On Tue, Jan 10, 2012 at 9:41 AM, barryhancock <bhancock@worldwidewarbirds.c
om> wrote:
com>
3 axis electric trim. Independent fuel vents for left and right tanks. Whil
e you're at it may as well do a ground up restoration. -;). The above is
what I have on my aircraft and the fuel imbalance problem is solved. I real
ize that's not a workable solutiion for everyone, however. -A fuel select
or valve would be great if someone would engineer that. -Blackwell's vent
switch system seems to work, also. -Other than that, get used to flying
sideways for awhile....
Happy Skidding,
Barry
--------
Barry Hancock
Worldwide Warbirds, Inc.
(877) 869-6458
www.worldwidewarbirds.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=362945#362945
rget="_blank">http://www.matronics.com/Navigator?Yak-List
http://forums.matronics.com
le, List Admin.
="_blank">http://www.matronics.com/contribution
--
... Blitz
Byron M. Fox
80 Milland Drive
Mill Valley, CA 94941
415-307-2405
Message 14
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| Subject: | Re: helmets (Noise) |
There is a long and a short version. Secure it to the airframe. The
female plugs are held in place with Adel clamps, so ......
Yes, it you leave it just hanging, it is a mess. :-)
Mark
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Roger Kemp
M.D.
Sent: Tuesday, January 10, 2012 11:02 AM
Subject: Re: Yak-List: Re: helmets (Noise)
<viperdoc@mindspring.com>
I have that adapter also to use with my current helmet. It is a bit
weighty and unruly under G.
Doc
Sent from my iPad
On Jan 9, 2012, at 4:29 PM, "Bitterlich, Mark G CIV Det Cherry Point,
MALS-14 64E" <mark.bitterlich@navy.mil> wrote:
Point, MALS-14 64E" <mark.bitterlich@navy.mil>
>
> Gibson-Barnes also has an adapter cable. Assuming you have the
standard U-174 connector on the end of your military helmet, you can
take out any pre-amp module that might have been in the O2 mask, and
using the stock mike and earpieces, the adapter cable will match the
impedances and you can use it with the original earpieces and microphone
element. It converts the U-174 connector to what is usually used in
general aviation, which is the mono headphone male connector, and the
standard mike plug.. the nomenclature of which I forget! Sorry.
>
> Anyway, I've tried it, it works.... but I'd recommend doing what the
folks below are talking about versus this. Just letting you know it's
there.
>
> Mark
>
>
> -----Original Message-----
> From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Roger Kemp MD
> Sent: Monday, January 09, 2012 5:16 PM
> To: yak-list@matronics.com
> Subject: RE: Yak-List: Re: helmets (Noise)
>
<viperdoc@mindspring.com>
>
> Roger...sigtronics makes a nice mic attachment as well as ear phones.
I did my original HGU 55 that way about 10 years ago. Not near the
hanger so do not have the parts lists. If you still have your O2 mask,
the sigtronics Lectric mic will mount directly in. You need to get the
general aviation OHM' d (forgot the exact Ohms- 5?) ear phones. Go to
www.gibson-barnes.com and click on helmet communication for the parts
you need. They even have the bayonet clip that you can mount you boom
mic on and use the bayonet receiver on your helmet without drilling
holes in your helmet for the boom mic mount.
> Doc
>
> -----Original Message-----
> From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Nelson Sprague
> Sent: Monday, January 09, 2012 3:11 PM
> To: yak-list@matronics.com
> Subject: Re: Yak-List: Re: helmets (Noise)
>
<nelsprague@hotmail.com>
>
> Brian I have my jet helmet from my air force days can I modify it for
use in the yak? Nels
>
> Brian Lloyd <brian@lloyd.com> wrote:
>
>> On Mon, Jan 9, 2012 at 8:20 AM, Herb Coussons <drc@wscare.com> wrote:
>>
>>> For clarification-
>>> Is the Westone molded earpiece a com speaker?
>>>
>>
>> Yes.
>>
>>
>>> Or just an earplug utilizing the existing coms of the helmet?
>>>
>>
>> No.
>>
>>
>>> It appears the CEP option is an in the ear com device that connects
>>> to the helmet coms, bypassing the earcup coms already installed?
>>>
>>
>> Not bypassing them. They are in parallel. You don't disable the stock
>> earspeakers so the helment/headset will continue to work normally
>> without the CEP earpieces plugged in.
>>
>> --
>> Brian Lloyd, WB6RQN/J79BPL
>> 3191 Western Dr.
>> Cameron Park, CA 95682
>> brian@lloyd.com
>> +1.767.617.1365 (Dominica)
>> +1.916.877.5067 (USA)
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
Message 15
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| Subject: | Re: Uneven fuel feed CJ6 |
The vent control system was never approved for anything but fuel bladders.
Do not install on standard metal tanks.
Gill
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com] On Behalf Of Byron Fox
Sent: Tuesday, January 10, 2012 2:08 PM
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
While still on this subject, a word of caution. Do as I say, not as I did.
I installed Bill Blackwell's fuel vent control system about 6 years ago.
And, as mentioned, it works well. Care, however, must be taken not to leave
a vent closed for too long. Our CJ fuel tanks are made of light weight
aluminum, and will collapse. Shortly after installing the system, I forgot
to open the left tank vent and landed. At the gas pump, I was startled when
I had to pull the left gas cap off to overcome the vacuum in the tank. The
consequent oil-canning noise really got my attention as air rushed back into
the tank.
OK, a new procedure -- cycle the vent switch every 5 minutes when balancing
the fuel tanks.
I thought I had dodged the bullet, but 6 years hence the left tank developed
a leak 3 weeks ago. Sure enough, the outboard end of my old tank had
collapsed inward a bit, making it concave instead of convex. Adjacent to the
grounding strap tab welded to the end of the tank a crack had developed. The
good news is that Doug Sapp had a new tank in stock.
So, either buy fuel bladders to replace the aluminum tanks, or cycle the
vent switches very, very frequently.
...Blitz
On Tue, Jan 10, 2012 at 9:41 AM, barryhancock
<bhancock@worldwidewarbirds.com> wrote:
<bhancock@worldwidewarbirds.com>
3 axis electric trim. Independent fuel vents for left and right tanks. While
you're at it may as well do a ground up restoration. ;). The above is what
I have on my aircraft and the fuel imbalance problem is solved. I realize
that's not a workable solutiion for everyone, however. A fuel selector
valve would be great if someone would engineer that. Blackwell's vent
switch system seems to work, also. Other than that, get used to flying
sideways for awhile....
Happy Skidding,
Barry
--------
Barry Hancock
Worldwide Warbirds, Inc.
(877) 869-6458 <tel:%28877%29%20869-6458>
www.worldwidewarbirds.com
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=362945#362945
==========
rget="_blank">http://www.matronics.com/Navigator?Yak-List
==========
http://forums.matronics.com
==========
le, List Admin.
="_blank">http://www.matronics.com/contribution
==========
--
... Blitz
Byron M. Fox
80 Milland Drive
Mill Valley, CA 94941
415-307-2405
Message 16
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| Subject: | Re: Uneven fuel feed CJ6 |
Fuel tank venting is a very interesting subject, especially when you are
trying to feed fuel evenly from two wing tanks at the same time. This is
one of those things where it pays to do some research into how others have
solved this problem before. Perhaps the most interesting source of
information on this is Cessna and how they have tried to deal with the
uneven fuel flow from the tanks in their aircraft that have a single "both
on" position. Reading the service bulletins over the years addressing all
the changes and "improvements" is very educational. And I would bet that
the Cessna engineers working on the problem probably had more knowledge and
experience than we do. Regardless, from what I can tell, they never really
found a satisfactory solution other than, "switch to one tank or the other."
You can do a lot but one of the things I would studiously avoid is separate
vents for the two (or four) tanks. If you want the two tanks to feed at the
same rate then the tank pressure must be exactly equal. The only way you
can assure that is to have only one source of tank pressurization for all
tanks. Cessna experimented with a single vent and dual vents. I believe
they finally settled on a single vent.
Blitz' comment about pulling a vacuum in a tank with the vent off tells me
that something else is seriously wrong. That implies that fuel was being
sucked from the tank with the vent turned off rather than that tank just
not feeding. The vent to the other tank and to the header tank should have
been open, allowing free flow of fuel from those tanks with no real suction
(other than normal 'head') on the tank with the switched-off vent. Blitz,
if that had happened to my plane you can bet your sweet ass that I would
ground my airplane and be tearing apart my vent system to figure out why
there was enough restriction in the flow of the other tanks to allow
ambient pressure to partially collapse the tank. Not good!
So, were it me (and I know that there are those of you who listen very
carefully to what I say and then do just the opposite :-) I would stick
with the single-point, high-pressure (belly) vent and then deal with uneven
fuel flow the simplest way possible -- fly with the ball toward the emptier
tank.
BTW, there is one small problem with the single-point vent that some of you
may have experienced -- the fuel siphon. It is possible to actually have
fuel siphon out of the vent onto the ground (a LOT of fuel). The fuel vent
has a loop in the cockpit that keeps the top of the vent line above the
high-fuel point in the tanks. It is possible if the tanks are completely
full and the plane is sitting in the hot sun, that the fuel can push up
through the vent which can start a siphon and cause a lot of fuel to end up
going overboard. The fix for this would be to put a vacuum-breaker valve at
the top of the vent loop in the cockpit.
So, my closing comment is -- eschew excessive complexity. Extra switches,
valves, indicators, etc., come under the heading of excessive complexity.
Proper maintenance of the fuel and vent system coupled with good piloting
technique is more than adequate to deal with the problem.
YMMV.
--
Brian Lloyd, WB6RQN/J79BPL
3191 Western Dr.
Cameron Park, CA 95682
brian@lloyd.com
+1.767.617.1365 (Dominica)
+1.916.877.5067 (USA)
Message 17
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| Subject: | Practical aspects of Exhibition category |
Re "Experimental, Exhibition," I know that Operating Limitations only list
the home airport and sometimes an alternate airport "...for maintenance."
What's practical though in terms of flying with your buddies to a nearby
airport for the $100 breakfast or to a friend's airport for a visit? Yes,
such is not a "...exhibition, fly-in, airshow, ..." but has anyone EVER been
"busted" for landing at other than their home airport?
Has anyone ever been hassled for stopping for fuel somewhere within their
proficiency area (or at other than their home airport) when not in route to
an event listed in their program letter?
Heck, has anyone ever even had to show their program letter to authorities
(as part of a ramp check, for example)?
Thank you!
Ted
Message 18
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| Subject: | Re: Practical aspects of Exhibition category |
Nope
Doc
Sent from my iPad
On Jan 10, 2012, at 7:36 PM, "Ted Waltman" <tedwaltman@gmail.com> wrote:
> Re "Experimental, Exhibition," I know that Operating Limitations only list
the home airport and sometimes an alternate airport "...for maintenance." W
hat's practical though in terms of flying with your buddies to a nearby airp
ort for the $100 breakfast or to a friend's airport for a visit? Yes, such i
s not a "...exhibition, fly-in, airshow, ..." but has anyone EVER been "bust
ed" for landing at other than their home airport?
>
>
>
> Has anyone ever been hassled for stopping for fuel somewhere within their p
roficiency area (or at other than their home airport) when not in route to a
n event listed in their program letter?
>
>
>
> Heck, has anyone ever even had to show their program letter to authorities
(as part of a ramp check, for example)?
>
>
>
> Thank you!
>
>
>
> Ted
>
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
Message 19
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| Subject: | Re: Practical aspects of Exhibition category |
VGVkDQpVbmRlciB0aGUgb2xkIDgxMzAuMkYgb25seSB0dXJiaW5lIHBvd2VyZWQgYWNmdCBvciB0
aG9zZSB0aGF0IGRpZG4ndCBmaXQgaW4gdGhlIGZpcnN0IHRocmVlIGdyb3VwcyB3ZXJlIHJlc3Ry
aWN0ZWQgdG8gdGFrZSBhbmQgbGFuZCBhdCB0aGUgc2FtZSBhaXJwb3J0LiANCg0KWW91IGNhbiBn
byB0byBvdGhlciBhaXJwb3J0cyBmb3IgcHJvZmljaWVuY3kgYnV0IG5lZWQgdG8gaW5jbHVkZSBp
biB5b3VyIHByb2dyYW0gbGV0dGVyIGFueXdoZXJlIGVsc2UgeW91IGdvIHRvIGV4aWJpdCwgZGlz
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YW4gImV2ZW50IiB0aGF0IHNob3VsZCBoYXZlIGJlZW4gbGlzdGVkIGluIHlvdXIgcHJvZ3JhbSBs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Message 20
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| Subject: | Re: Practical aspects of Exhibition category |
Never
Bill
On Jan 10, 2012, at 7:36 PM, "Ted Waltman" <tedwaltman@gmail.com> wrote:
> Re "Experimental, Exhibition," I know that Operating Limitations only list
the home airport and sometimes an alternate airport "...for maintenance." W
hat's practical though in terms of flying with your buddies to a nearby airp
ort for the $100 breakfast or to a friend's airport for a visit? Yes, such i
s not a "...exhibition, fly-in, airshow, ..." but has anyone EVER been "bust
ed" for landing at other than their home airport?
>
> Has anyone ever been hassled for stopping for fuel somewhere within their p
roficiency area (or at other than their home airport) when not in route to a
n event listed in their program letter?
>
> Heck, has anyone ever even had to show their program letter to authorities
(as part of a ramp check, for example)?
>
> Thank you!
>
> Ted
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
Message 21
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|
| Subject: | Re: Practical aspects of Exhibition category |
Yes
Sent from my iPad
On Jan 10, 2012, at 9:07 PM, "Roger Kemp M.D." <viperdoc@mindspring.com> wro
te:
> Nope
> Doc
>
> Sent from my iPad
>
> On Jan 10, 2012, at 7:36 PM, "Ted Waltman" <tedwaltman@gmail.com> wrote:
>
>> Re "Experimental, Exhibition," I know that Operating Limitations only lis
t the home airport and sometimes an alternate airport "...for maintenance."
What's practical though in terms of flying with your buddies to a nearby ai
rport for the $100 breakfast or to a friend's airport for a visit? Yes, suc
h is not a "...exhibition, fly-in, airshow, ..." but has anyone EVER been "b
usted" for landing at other than their home airport?
>>
>>
>>
>> Has anyone ever been hassled for stopping for fuel somewhere within their
proficiency area (or at other than their home airport) when not in route to
an event listed in their program letter?
>>
>>
>>
>> Heck, has anyone ever even had to show their program letter to authoritie
s (as part of a ramp check, for example)?
>>
>>
>>
>> Thank you!
>>
>>
>>
>> Ted
>>
>>
>>
>> =========================
=========
>> ef="http://www.matronics.com/Navigator?Yak-List">http://www.matronics.c
om/Navigator?Yak-List
>> =========================
=========
>> ums.matronics.com">http://forums.matronics.com
>> =========================
=========
>> http://www.matronics.com/contribution">http://www.matronics.com/contribut
ion
>> =========================
=========
>>
>
>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>
Message 22
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| Subject: | Re: Uneven fuel feed CJ6 |
I would agree with Brian's closing comments here 100%.
Vent shut off valves are an abomination and any other changes to the
vent system are a waste of time and money and could make matters worse..
In fact the vent system is not the problem! It is by no means perfect
but (unless it is plugged, partially plugged or a line is kinked) it
accounts for a very minor part of the uneven fuel feed and only because
of the unequal pipeline lengths to the main tanks.
Before I go any further I must note that I refer only to the CJ6 and
none of the Yak series of which I have no knowledge.
The real problem is the design of the header tank flapper valves. There
are three of these valves in the aircraft one of which is the fuel feed
line non-return valve. In this application the valve design is
excellent and it works perfectly.
That is not the case in the header tank.
In the engine fuel line the (very low) head pressure from the weight of
the fuel opposing the zero or negative pressure from the fuel pump
readily opens the flapper.
In the header tank the same conditions do not exist.
Lets assume full tanks on both sides and further assume that fuel load
produces a 1 psi pressure to open each flapper (actually it will be
closer to 0.1 psi). Lets also assume a perfectly clean and equal vent
system and the aircraft is flying in a vacuum with zero turbulence and
zero yaw so there are no other forces involved.
Since the pressure to open both flappers is the same and there is no
fuel movement other than that generated by the fuel pump both flappers
should be open and the tanks should drain equally.
Well, lets put in a little reality. Only one is open, probably the left
side since the vent line and the fuel feed line are shorter and produce
slightly less flow resistance.
As the fuel leaves the RH tank the pressure in the header tank is
decreasing and the 1psi on the left side should open that flapper. In
fact, with the assumptions we have made above, it will not open until
the RH tank is near empty.
The reason for this is even though we have approx. equal pressure in psi
the actual force on each side of the flapper is nowhere near equal.
The numbers to follow are approx. examples only, I did this work some
years ago and do not recall the actual numbers.
The 1 psi acting to open the flapper is applying pressure to an area of
0.125 sq. in. or a force of 0.125 lbs.
The 1 psi holding the valve closed is applying pressure to an area of
0.44 sq. in for a force of 0.44 lbs.
The only factor that allows this system to work is fuel movement due to
turbulence, yaw, etc. Fortunately it is difficult to fly in a vacuum.
The fix of course is to modify the valve assy so the force acting on
each side is near equal.
I have done five CJ's so far with really excellent results on the 3
flying ones. Doug Sapps and my own are the two exceptions since neither
is flying yet. (Who goes first Doug?)
I was able to do a lot of testing with the first one and rarely ever saw
an imbalance over 10 lts. except with a point roll or a true slow roll.
With the valves flapping freely that action will give an imbalance but
one minute of level flight and it is back to normal.
Theoretically, since there is some vent & feed line difference and it is
impractical to get a perfect line contact valve seat, you could expect
an imbalance of up to 13 lts in a turbulence and yaw free flight.
If anyone wants further info let me know.
Walt
wlannon@shaw.ca
----- Original Message -----
From: Brian Lloyd
To: yak-list@matronics.com
Sent: Tuesday, January 10, 2012 3:41 PM
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
Fuel tank venting is a very interesting subject, especially when you
are trying to feed fuel evenly from two wing tanks at the same time.
This is one of those things where it pays to do some research into how
others have solved this problem before. Perhaps the most interesting
source of information on this is Cessna and how they have tried to deal
with the uneven fuel flow from the tanks in their aircraft that have a
single "both on" position. Reading the service bulletins over the years
addressing all the changes and "improvements" is very educational. And I
would bet that the Cessna engineers working on the problem probably had
more knowledge and experience than we do. Regardless, from what I can
tell, they never really found a satisfactory solution other than,
"switch to one tank or the other."
You can do a lot but one of the things I would studiously avoid is
separate vents for the two (or four) tanks. If you want the two tanks to
feed at the same rate then the tank pressure must be exactly equal. The
only way you can assure that is to have only one source of tank
pressurization for all tanks. Cessna experimented with a single vent and
dual vents. I believe they finally settled on a single vent.
Blitz' comment about pulling a vacuum in a tank with the vent off
tells me that something else is seriously wrong. That implies that fuel
was being sucked from the tank with the vent turned off rather than that
tank just not feeding. The vent to the other tank and to the header tank
should have been open, allowing free flow of fuel from those tanks with
no real suction (other than normal 'head') on the tank with the
switched-off vent. Blitz, if that had happened to my plane you can bet
your sweet ass that I would ground my airplane and be tearing apart my
vent system to figure out why there was enough restriction in the flow
of the other tanks to allow ambient pressure to partially collapse the
tank. Not good!
So, were it me (and I know that there are those of you who listen very
carefully to what I say and then do just the opposite :-) I would stick
with the single-point, high-pressure (belly) vent and then deal with
uneven fuel flow the simplest way possible -- fly with the ball toward
the emptier tank.
BTW, there is one small problem with the single-point vent that some
of you may have experienced -- the fuel siphon. It is possible to
actually have fuel siphon out of the vent onto the ground (a LOT of
fuel). The fuel vent has a loop in the cockpit that keeps the top of the
vent line above the high-fuel point in the tanks. It is possible if the
tanks are completely full and the plane is sitting in the hot sun, that
the fuel can push up through the vent which can start a siphon and cause
a lot of fuel to end up going overboard. The fix for this would be to
put a vacuum-breaker valve at the top of the vent loop in the cockpit.
So, my closing comment is -- eschew excessive complexity. Extra
switches, valves, indicators, etc., come under the heading of excessive
complexity. Proper maintenance of the fuel and vent system coupled with
good piloting technique is more than adequate to deal with the problem.
YMMV.
--
Brian Lloyd, WB6RQN/J79BPL
3191 Western Dr.
Cameron Park, CA 95682
brian@lloyd.com
+1.767.617.1365 (Dominica)
+1.916.877.5067 (USA)
Message 23
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| Subject: | Re: Uneven fuel feed CJ6 |
I just proof read my diatribe. Always do that just after I send it!
About half way through I wrote "As fuel leaves the RH
tank-----------------and the 1 psi on the LEFT side
--------------------------will not open until the
RH-----------------------"
Should read LH----------right------------LH.
Oh well!!!
Walt
----- Original Message -----
From: Walter Lannon
To: yak-list@matronics.com
Sent: Tuesday, January 10, 2012 8:45 PM
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
I would agree with Brian's closing comments here 100%.
Vent shut off valves are an abomination and any other changes to the
vent system are a waste of time and money and could make matters worse..
In fact the vent system is not the problem! It is by no means perfect
but (unless it is plugged, partially plugged or a line is kinked) it
accounts for a very minor part of the uneven fuel feed and only because
of the unequal pipeline lengths to the main tanks.
Before I go any further I must note that I refer only to the CJ6 and
none of the Yak series of which I have no knowledge.
The real problem is the design of the header tank flapper valves.
There are three of these valves in the aircraft one of which is the fuel
feed line non-return valve. In this application the valve design is
excellent and it works perfectly.
That is not the case in the header tank.
In the engine fuel line the (very low) head pressure from the weight
of the fuel opposing the zero or negative pressure from the fuel pump
readily opens the flapper.
In the header tank the same conditions do not exist.
Lets assume full tanks on both sides and further assume that fuel load
produces a 1 psi pressure to open each flapper (actually it will be
closer to 0.1 psi). Lets also assume a perfectly clean and equal vent
system and the aircraft is flying in a vacuum with zero turbulence and
zero yaw so there are no other forces involved.
Since the pressure to open both flappers is the same and there is no
fuel movement other than that generated by the fuel pump both flappers
should be open and the tanks should drain equally.
Well, lets put in a little reality. Only one is open, probably the
left side since the vent line and the fuel feed line are shorter and
produce slightly less flow resistance.
As the fuel leaves the RH tank the pressure in the header tank is
decreasing and the 1psi on the left side should open that flapper. In
fact, with the assumptions we have made above, it will not open until
the RH tank is near empty.
The reason for this is even though we have approx. equal pressure in
psi the actual force on each side of the flapper is nowhere near equal.
The numbers to follow are approx. examples only, I did this work some
years ago and do not recall the actual numbers.
The 1 psi acting to open the flapper is applying pressure to an area
of 0.125 sq. in. or a force of 0.125 lbs.
The 1 psi holding the valve closed is applying pressure to an area of
0.44 sq. in for a force of 0.44 lbs.
The only factor that allows this system to work is fuel movement due
to turbulence, yaw, etc. Fortunately it is difficult to fly in a
vacuum.
The fix of course is to modify the valve assy so the force acting on
each side is near equal.
I have done five CJ's so far with really excellent results on the 3
flying ones. Doug Sapps and my own are the two exceptions since neither
is flying yet. (Who goes first Doug?)
I was able to do a lot of testing with the first one and rarely ever
saw an imbalance over 10 lts. except with a point roll or a true slow
roll.
With the valves flapping freely that action will give an imbalance but
one minute of level flight and it is back to normal.
Theoretically, since there is some vent & feed line difference and it
is impractical to get a perfect line contact valve seat, you could
expect an imbalance of up to 13 lts in a turbulence and yaw free flight.
If anyone wants further info let me know.
Walt
wlannon@shaw.ca
----- Original Message -----
From: Brian Lloyd
To: yak-list@matronics.com
Sent: Tuesday, January 10, 2012 3:41 PM
Subject: Re: Yak-List: Re: Uneven fuel feed CJ6
Fuel tank venting is a very interesting subject, especially when you
are trying to feed fuel evenly from two wing tanks at the same time.
This is one of those things where it pays to do some research into how
others have solved this problem before. Perhaps the most interesting
source of information on this is Cessna and how they have tried to deal
with the uneven fuel flow from the tanks in their aircraft that have a
single "both on" position. Reading the service bulletins over the years
addressing all the changes and "improvements" is very educational. And I
would bet that the Cessna engineers working on the problem probably had
more knowledge and experience than we do. Regardless, from what I can
tell, they never really found a satisfactory solution other than,
"switch to one tank or the other."
You can do a lot but one of the things I would studiously avoid is
separate vents for the two (or four) tanks. If you want the two tanks to
feed at the same rate then the tank pressure must be exactly equal. The
only way you can assure that is to have only one source of tank
pressurization for all tanks. Cessna experimented with a single vent and
dual vents. I believe they finally settled on a single vent.
Blitz' comment about pulling a vacuum in a tank with the vent off
tells me that something else is seriously wrong. That implies that fuel
was being sucked from the tank with the vent turned off rather than that
tank just not feeding. The vent to the other tank and to the header tank
should have been open, allowing free flow of fuel from those tanks with
no real suction (other than normal 'head') on the tank with the
switched-off vent. Blitz, if that had happened to my plane you can bet
your sweet ass that I would ground my airplane and be tearing apart my
vent system to figure out why there was enough restriction in the flow
of the other tanks to allow ambient pressure to partially collapse the
tank. Not good!
So, were it me (and I know that there are those of you who listen
very carefully to what I say and then do just the opposite :-) I would
stick with the single-point, high-pressure (belly) vent and then deal
with uneven fuel flow the simplest way possible -- fly with the ball
toward the emptier tank.
BTW, there is one small problem with the single-point vent that some
of you may have experienced -- the fuel siphon. It is possible to
actually have fuel siphon out of the vent onto the ground (a LOT of
fuel). The fuel vent has a loop in the cockpit that keeps the top of the
vent line above the high-fuel point in the tanks. It is possible if the
tanks are completely full and the plane is sitting in the hot sun, that
the fuel can push up through the vent which can start a siphon and cause
a lot of fuel to end up going overboard. The fix for this would be to
put a vacuum-breaker valve at the top of the vent loop in the cockpit.
So, my closing comment is -- eschew excessive complexity. Extra
switches, valves, indicators, etc., come under the heading of excessive
complexity. Proper maintenance of the fuel and vent system coupled with
good piloting technique is more than adequate to deal with the problem.
YMMV.
--
Brian Lloyd, WB6RQN/J79BPL
3191 Western Dr.
Cameron Park, CA 95682
brian@lloyd.com
+1.767.617.1365 (Dominica)
+1.916.877.5067 (USA)
href="http://www.matronics.com/Navigator?Yak-List">http://www.matronics
.com/Navigator?Yak-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/c
Message 24
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| Subject: | Re: Uneven fuel feed CJ6 |
Walt... what would happen with NO flapper valves on the header tank...?
Dave Laird
N63536 1983 CJ6A "Betty"
Dallas * Austin
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