Today's Message Index:
----------------------
1. 12:23 AM - Re: G Tolerance and Hydration (CD 2.0)
2. 07:44 AM - Re: G Tolerance and Hydration (Herb Coussons)
3. 08:23 AM - Re: Re: fuel flow from tanks (Brian Lloyd)
4. 08:29 AM - Re: Re: G Tolerance and Hydration (Brian Lloyd)
5. 08:30 AM - Re: G Tolerance and Hydration (Brian Lloyd)
6. 09:07 AM - Re: Re: fuel flow from tanks (Larry Pine)
7. 09:31 AM - Re: Re: fuel flow from tanks (Brian Lloyd)
8. 07:14 PM - Panel (Bill Geipel)
9. 07:35 PM - Re: G Tolerance and Hydration (CD 2.0)
10. 08:15 PM - Fuel vents on yak fuel tanks (javiercarrascob)
11. 08:18 PM - What oil types can be mixed on an M-14p? (javiercarrascob)
12. 08:51 PM - Re: Re: fuel flow from tanks (Walter Lannon)
13. 09:26 PM - Re: What oil types can be mixed on an M-14p? (Brian Lloyd)
14. 10:04 PM - Re: What oil types can be mixed on an M-14p? (CD 2.0)
15. 11:51 PM - Re: Fuel vents on yak fuel tanks (CD 2.0)
Message 1
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| Subject: | Re: G Tolerance and Hydration |
A fire protective suit is recommended. When you're flying in shorts, shirt etc,
remember you're surrounded by highly flammable liquids... not a good idea...
but let's not forget how the thickness of the Nomex flight suits could certainly
increase body temperatures turning into faster dehydration. Let's not underestimate
the dangers of dehydration and how "important" is to drink "plenty
and often" before getting in the cockpit.
Keep in mind that when your body gets hot, it sweats. The heat from your body
is dissipated because it's spent turning the water on your skin into vapor. As
the sweat evaporates from your body, more sweat takes its place for as long as
your body decides that it needs to cool itself down, the advantage is that your
body can regulate its temperature, the disadvantage being that you lose water
and can dehydrate.
Now that bottle of water you just sucked down... is going to take almost "45 minutes"
to be absorbed into your blood stream, another factor to take into consideration
as when you may be feeling thirsty, it could be too late.
When you begin to lose too much water, your body can heat up faster causing you
to suffer from heat exhaustion... which is something you don't want to mess with...
Initial symptoms include nausea, dizziness, and lack of sweat (because
you're dehydrated). With continued exposure to heat, other symptoms include ringing
in the ears, headache, and loss of muscle control... just to start...
Upon noticing the first symptom, dive fast, land in a rush, get out of the heat
and replenish the body's water immediately.
Carl
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=347902#347902
Message 2
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| Subject: | Re: G Tolerance and Hydration |
It looks like they use something heavier than the typical used military
issue. They use something heavier - like a NASCAR race type outfit.
Jimmy? Still on the list. After OSH, I'll call him.
Herb
Dr. Herb Coussons, MD
drc@wscare.com
2641 Development Drive
Green Bay, WI 54311
Cell 920-639-8434
Work 920-338-6868
Fax 920-338-6869
On Jul 27, 2011, at 11:50 PM, Brian Lloyd wrote:
>
>
> On Wed, Jul 27, 2011 at 8:02 PM, Herb Coussons <drc@wscare.com> wrote:
> The cool shirt was also promoted by the Aeroshell team.
> They also wear flight suits, but recognize the debilitating effects of
heat and dehydration on G-tolerance.
>
> Interesting. Do they wear multiple layers of nomex? That seems to be
the key.
>
> For grins I weighed, flew with Sergei for 1hr 10mins and re-weighed.
> Lost 2.3 pounds !! Just over one liter.
> (All sweat - no caca !!)
>
> No surprise at all. Makes sense to me.
>
> --
> 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 flow from tanks |
On Wed, Jul 27, 2011 at 10:24 PM, CD 2.0 <dbowie2007@hotmail.com> wrote:
>
> A selector valve would be a good solution to uneven fuel feeding problems
,
> hands down the best solution to this problem - but switching the vents on
> and off, as Warren mentioned, in my opinion isn't a bad idea after all
> knowing the difficulties with installing a fuel selector valve in CJ's an
d
> Yak's... The main idea here is to avoid getting empty in one tank and
> wonder (at 3500 feet) if the full tank will take over or not :)
>
Hint: put the boost pump at the low-point in the system.
>
> ... keep an eye on the tanks to check for imbalance and always watch the
> ball.... using rudder trim to correct for uneven fuel feed seems to be t
he
> method most used... but for long cross country trips to air shows, it may
be
> safer setting the GPS scheduler alarm to sound every 15 minutes. When the
> alarm goes off, check for imbalance and do appropriate wing correction to
> minimize the problem... and it would be even better if we could simply
> switch to the fullest tank with the selector valve. Same goes when enteri
ng
> the pattern, switch to the fullest tank...
>
You're a man after my own heart. Precisely what I was thinking.
>
> ... I still think the lack of a fuel selector is a major design defect,
> especially when they where aware of this problem from the very first test
s.
> If they were really concerned about the =93complexity=94 of switching tan
ks they
> could have done what Cessna did long ago, a Fuel selector and a Both
> setting...
>
We are definitely on the same page, Carl.
--
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: G Tolerance and Hydration |
On Thu, Jul 28, 2011 at 12:21 AM, CD 2.0 <dbowie2007@hotmail.com> wrote:
>
> A fire protective suit is recommended. When you're flying in shorts, shirt
> etc, remember you're surrounded by highly flammable liquids... not a good
> idea... but let's not forget how the thickness of the Nomex flight suits
> could certainly increase body temperatures turning into faster dehydration.
> Let's not underestimate the dangers of dehydration and how "important" is
> to drink "plenty and often" before getting in the cockpit.
>
> Keep in mind that when your body gets hot, it sweats. The heat from your
> body is dissipated because it's spent turning the water on your skin into
> vapor. As the sweat evaporates from your body, more sweat takes its place
> for as long as your body decides that it needs to cool itself down, the
> advantage is that your body can regulate its temperature, the disadvantage
> being that you lose water and can dehydrate.
>
Except that the flight suit reduces or prevents free airflow over the body
and negates the evaporative cooling effect. You have to move a LOT of air
over the suit in order to restore normal skin evaporative cooling.
Now that bottle of water you just sucked down... is going to take almost "45
> minutes" to be absorbed into your blood stream, another factor to take into
> consideration as when you may be feeling thirsty, it could be too late.
>
> When you begin to lose too much water, your body can heat up faster causing
> you to suffer from heat exhaustion... which is something you don't want to
> mess with... Initial symptoms include nausea, dizziness, and lack of sweat
> (because you're dehydrated). With continued exposure to heat, other symptoms
> include ringing in the ears, headache, and loss of muscle control... just to
> start...
>
> Upon noticing the first symptom, dive fast, land in a rush, get out of the
> heat and replenish the body's water immediately.
>
You know, when you really analyze this, you see that the two problems, fire
protection and body cooling, are mutually exclusive. You really need to take
another look at how you want to deal with the problem. The "perfect"
solution is the one that the race car drivers have adopted: full,
multi-layer fire protection with a separate, active cooling system (cool
shirt). If you aren't going to go that way you may actually find that, in
terms of total risk reduction, shorts and a t-shirt are indeed the
lower-risk compromise.
--
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: G Tolerance and Hydration |
On Thu, Jul 28, 2011 at 7:41 AM, Herb Coussons <drc@wscare.com> wrote:
> It looks like they use something heavier than the typical used military
> issue. They use something heavier - like a NASCAR race type outfit.
>
Yup! That is a hint.
--
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 flow from tanks |
I've found that peterbuilt trucks makes a pneumatic toggle switch that had electrical
contacts. This way you can connect the toggle switches to a panel light.
This way it would be very noticable if a vent was closed. I had been on board
where the pilot forgot a vent was closed, collapsed the tank and flamed the
engine out..
Larry Pine
N8181C
CJ6/m14p
Brian Lloyd <brian@lloyd.com> wrote:
>On Wed, Jul 27, 2011 at 10:24 PM, CD 2.0 <dbowie2007@hotmail.com> wrote:
>
>>
>> A selector valve would be a good solution to uneven fuel feeding problems,
>> hands down the best solution to this problem - but switching the vents on
>> and off, as Warren mentioned, in my opinion isn't a bad idea after all
>> knowing the difficulties with installing a fuel selector valve in CJ's and
>> Yak's... The main idea here is to avoid getting empty in one tank and
>> wonder (at 3500 feet) if the full tank will take over or not :)
>>
>
>Hint: put the boost pump at the low-point in the system.
>
>
>>
>> ... keep an eye on the tanks to check for imbalance and always watch the
>> ball.... using rudder trim to correct for uneven fuel feed seems to be the
>> method most used... but for long cross country trips to air shows, it may be
>> safer setting the GPS scheduler alarm to sound every 15 minutes. When the
>> alarm goes off, check for imbalance and do appropriate wing correction to
>> minimize the problem... and it would be even better if we could simply
>> switch to the fullest tank with the selector valve. Same goes when entering
>> the pattern, switch to the fullest tank...
>>
>
>You're a man after my own heart. Precisely what I was thinking.
>
>
>>
>> ... I still think the lack of a fuel selector is a major design defect,
>> especially when they where aware of this problem from the very first tests.
>> If they were really concerned about the complexity of switching tanks they
>> could have done what Cessna did long ago, a Fuel selector and a Both
>> setting...
>>
>
>We are definitely on the same page, Carl.
>
>--
>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 7
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| Subject: | Re: fuel flow from tanks |
On Thu, Jul 28, 2011 at 9:04 AM, Larry Pine <threein60@yahoo.com> wrote:
>
> I've found that peterbuilt trucks makes a pneumatic toggle switch that had
> electrical contacts. This way you can connect the toggle switches to a panel
> light. This way it would be very noticable if a vent was closed. I had
> been on board where the pilot forgot a vent was closed, collapsed the tank
> and flamed the engine out..
>
This is why I am not a fan of messing with tank venting. I have experienced
a collapsed tank due to vent system failure. The only reason it did not
result in an "incident" is that I noticed irregular behavior of the fuel
level indicator and landed quickly. Normally the gauge doesn't show a sudden
and steady increase in fuel in the selected tank. The tank collapsed from
the bottom up, pushing up the fuel sender float. It was my "full" tank that
failed. Fortunately there was sufficient fuel in my not-full tank for a safe
conclusion of my flight.
So, I would not willingly block a vent for any reason.
--
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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Would anyone have a front instrument panel for a yak 52 that is not in an airplane
that you could trace on a big piece of paper? I want to cut a new panel and
be ready before I take mine out.
Thank you.
Bill
Message 9
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| Subject: | Re: G Tolerance and Hydration |
Brian, excellent point. It makes complete sense. Hopefully a manufacture can
come up with the best of both worlds, fire protection with cooling capabilities
or lighter, thinner materials to prevent body overheating.
I believe there is a profitable enough market in the aviation industry to keep
innovation and bring to production flight suits with similar qualities of those
that comply and exceed SFI standards... or who knows... we may all have to look
like Nascar or F1 drivers in military airplanes... :)
Carl
brian(at)lloyd.com wrote:
>
> You know, when you really analyze this, you see that the two problems, fire protection
and body cooling, are mutually exclusive. You really need to take another
look at how you want to deal with the problem. The "perfect" solution is
the one that the race car drivers have adopted: full, multi-layer fire protection
with a separate, active cooling system (cool shirt). If you aren't going
to go that way you may actually find that, in terms of total risk reduction, shorts
and a t-shirt are indeed the lower-risk compromise.
>
>
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=347965#347965
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| Subject: | Fuel vents on yak fuel tanks |
Hello Team,
I'd been following the "fuel flow from tanks" topic and in the same token I have
a question regarding the Fuel Vents.
I have noticed small drops falling from the right wing (when looking at it sitting
in flying position in my Yak-55m), the first time I noticed was doing vertical
flight but I dismissed as condensation or rain as the plane sat overnight
with no covers while there was a storm (and yes as soon as I preflight the plane
I saw water coming off the ailerons.)
So I decided to look at again and I can see what I think is fuel drops leaving
the plane from the right wing while doing acro (inverted or vertical) but it is
only from the right wing and it does not amount to anything on the fuel levels
(if I fly heavy on the right wing I have more fuel there if I fly heavy on
the left, it cross feed to the left).
While I do cross country, there is no loss of fuel so leveled flight or seating
on the tarmac means no fuel loss.
So is this normal? and I never noticed before? I assume that some fuel will get
caught in the fuel vents and can drip off. but I rather hear your opinions.
Thanks, Javier
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=347967#347967
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| Subject: | What oil types can be mixed on an M-14p? |
Hello Gang,
Hope you are enjoying EAA week, I'm currently using Aeroshell 100W. for my M-14p
powered Yak-55m.
As you may know when you do cross country in a '55 there is not much room to bring
oil with you.
I find my self landing at FBOs that don't carry either Aeroshell 100W or 120w in
summer (80w in winter). Not to mention Phillips 25w-60 is even harder to find
(hence I use 100W).
So
Question 1: Can I mix/Blend Aeroshell 100w with 100? I understand that one is ashless
dispersant and the other one is straigh mineral (no aditives)?
Question 2 : Can I mix 100w with 80w when it starts to get cold?
Question 3: Can I mix Aeroshell 100w with Phillips 25w-60?
Thanks, Javier
N5245H
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=347968#347968
Message 12
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| Subject: | Re: fuel flow from tanks |
----- Original Message -----
From: Brian Lloyd
To: yak-list@matronics.com
Sent: Thursday, July 28, 2011 9:29 AM
Subject: Re: Yak-List: Re: fuel flow from tanks
Brian Lloyd wrote:------
This is why I am not a fan of messing with tank venting. I have
experienced a collapsed tank due to vent system failure. The only reason
it did not result in an "incident" is that I noticed irregular behavior
of the fuel level indicator and landed quickly. Normally the gauge
doesn't show a sudden and steady increase in fuel in the selected tank.
The tank collapsed from the bottom up, pushing up the fuel sender float.
It was my "full" tank that failed. Fortunately there was sufficient fuel
in my not-full tank for a safe conclusion of my flight.
So, I would not willingly block a vent for any reason.
Nor would I.
I have seen the results a few times over the past years.
In one case a 4 engine airliner (Mexico City to Toronto) that flew
through a swarm of locusts (or similar) critters shortly after take-off.
They continued as there was no apparent problem but made a safe emerg.
landing in the US after strange engine problems. All fuel tanks ( bag
type) were sucked to the top.
Two T6/Harvard incidents one a safe landing the other a successful
ditching. In both cases fuel tanks sucked to the top of the wing. In
one I could touch the tank bottom with a finger. These are very
substantial al. alloy tanks, Not bags.
So, for me shutting off a vent is not an option.
Nor is it necessary and I am referring here ONLY to the CJ, not any of
the Yak series since I have no direct knowledge of their systems.
I do not like the single point system and would prefer a simple
selector valve and individual vents like the T6.
But that is not an easy option for the CJ.
So I studied the CJ system and discovered a rather serious design flaw
with the header tank flapper valves. I have now modified the valves for
5 CJ's (two of which are still in restoration).
The other 3 are flying regularly and have experienced no fuel
imbalance problems whatsoever.
The Chinese also recognised the problem and did a similar but less
effective mod. at some point in the aircraft's history. Don't know when
they did that but have seen some very late model CJ's with both old and
new style valves installed.
The new style valve can not be further modified but probably doesn't
need it.
Single point is still and will remain a problem and I recommend a vent
cover and "Remove before Flight" flag at all times when parked.
I'm sure I would bore everone to tears (if I haven't already) if I get
into the mod details here.
Walt
Message 13
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| Subject: | Re: What oil types can be mixed on an M-14p? |
On Thu, Jul 28, 2011 at 8:15 PM, javiercarrascob
<javiercarrascob@yahoo.com>wrote:
> Question 1: Can I mix/Blend Aeroshell 100w with 100? I understand that one
> is ashless dispersant and the other one is straigh mineral (no aditives)?
>
Yes.
>
> Question 2 : Can I mix 100w with 80w when it starts to get cold?
>
Yes.
>
> Question 3: Can I mix Aeroshell 100w with Phillips 25w-60?
>
Yes.
--
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 14
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| Subject: | Re: What oil types can be mixed on an M-14p? |
Javier, not only are all Aeroshell oils compatible with other approved aircraft
piston engine oils, but pretty much all oils available are compatible, synthetics,
blends and dino oils. I personally prefer not to mix brands, but in all
likelihood it is perfectly safe to do so. Also elaborate precautions are not
needed when changing from similarly approved aircraft engine oils, as long as
these oils are qualified products.
Aeroshell 100 is mainly used as break in oil for new steel or chrome cylinders.
It has been said that it isn't particularly good at either lubricating or cleansing...
The resulting high levels of friction may speed up the break-in process
but isn't approved for "long-term" use in an engine. If you use this type
of oil for break in, you should plan to drain it within 15-25 hours (the sooner
the better) and replace it with a high quality ashless dispersant (AD) oils
as the Aeroshell W 100.
Aeroshell W 100 and W 80 offer good lubrication and good cleansing action. Single
grade oil is especially good at protecting engines against internal corrosion,
because it is very thick at ordinary room temperature and sticks to engine
parts without stripping off as readily as multi grade oils. However, single-grade
oil is not recommended for non-preheated cold weather operation. When starting
in sub freezing temperatures... typical hard winters in the North East,
single-grade oil may be too thick to provide adequate lubrication in the first
minute or two of engine operation.
Phillips 25w-60 is similar to single grade AD oil (W100/80), but has a viscosity
index enhancer which causes the oil to maintain a more constant viscosity over
a wide range of temperatures... This oil remains much thinner and more easily
pourable at room temperature than single grade oil. This is a great advantage
for cold weather starting if a preheat or heated hangar is not available.
On the other hand, multi vis oil will strip off engine parts much more readily
during periods of disuse... so it doesn't provide nearly as good corrosion protection
as single grade oil does.
AeroShell W80 for cold climate regions (-17 - 21C)
AeroShell Oil W100 for temperate regions (15 - 30C)
AeroShell Oil W120 for warmer climates (above 26C).
Carl
javiercarrascob wrote:
> Hello Gang,
>
> Hope you are enjoying EAA week, I'm currently using Aeroshell 100W. for my M-14p
powered Yak-55m.
>
> As you may know when you do cross country in a '55 there is not much room to
bring oil with you.
>
> I find my self landing at FBOs that don't carry either Aeroshell 100W or 120w
in summer (80w in winter). Not to mention Phillips 25w-60 is even harder to find
(hence I use 100W).
>
> So
>
> Question 1: Can I mix/Blend Aeroshell 100w with 100? I understand that one is
ashless dispersant and the other one is straigh mineral (no aditives)?
>
> Question 2 : Can I mix 100w with 80w when it starts to get cold?
>
> Question 3: Can I mix Aeroshell 100w with Phillips 25w-60?
>
> Thanks, Javier
> N5245H
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=347978#347978
Message 15
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| Subject: | Re: Fuel vents on yak fuel tanks |
Javier, a few years a go, a Yak 50 had a fuel leak happening only while practicing
aerobatics. The aircraft was landed for inspection and the A&P's found nothing.
They opened all access doors and panels looking for signs of leaking fuel
and found no evidence. Flying again and everything went normally until a
snaproll at the top of a loop was performed at approximately 2300 ft. At this
time fuel fumes filled the cockpit and raw fuel was seen in the cockpit... as
the aircraft accelerated down to the backside of the loop, pilot's vision was
blurry and the fumes were significant. Landing safely, they now discovered a
significant crack in the fuel tank.
Apparently a static grounding tab welded to the tank had more than likely resulted
in excessive stress being applied to it from a bonding strap that did not
have enough slack. During repeated high G aerobatic flight, the lack of slack
in the bonding strap caused it to pull on the welded tab attached to the fuel
tank which then caused the beginning of the crack (and resultant fuel leak) to
form. The faint initial fuel fumes that the pilot experienced earlier were when
the crack was just beginning to form and under heavy G loading a very small
amount of fuel leaked out. The design of the tank and the location of the crack
caused it to finally leak badly only when it was nearly full and negative G
was applied.
It could be just a simple loose connection in the fuel system but the fact that
it only leaks while pulling G's could indicate that it's something else. Check
if the fuel tank grounding tab weld is damaged or cracked causing the fuel
leak. If the tank is shifted from its mountings it could strain the tank ground
strap attached to the tank grounding tab and every heavy 'G' loading could apply
excessive stress to the tank tab.
Keep us posted with this issue.
Carl
javiercarrascob wrote:
> Hello Team,
>
> I'd been following the "fuel flow from tanks" topic and in the same token I have
a question regarding the Fuel Vents.
>
> I have noticed small drops falling from the right wing (when looking at it sitting
in flying position in my Yak-55m), the first time I noticed was doing vertical
flight but I dismissed as condensation or rain as the plane sat overnight
with no covers while there was a storm (and yes as soon as I preflight the
plane I saw water coming off the ailerons.)
>
> So I decided to look at again and I can see what I think is fuel drops leaving
the plane from the right wing while doing acro (inverted or vertical) but it
is only from the right wing and it does not amount to anything on the fuel levels
(if I fly heavy on the right wing I have more fuel there if I fly heavy on
the left, it cross feed to the left).
>
> While I do cross country, there is no loss of fuel so leveled flight or seating
on the tarmac means no fuel loss.
>
> So is this normal? and I never noticed before? I assume that some fuel will get
caught in the fuel vents and can drip off. but I rather hear your opinions.
>
> Thanks, Javier
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