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1. 02:58 PM - Re: Here's an odd question ()
2. 04:47 PM - Re: Re: Here's an odd question (Galin Hernandez)
3. 09:04 PM - Re: Re: Here's an odd question (Larry David)
4. 09:22 PM - KIS TRI Nose Leg (Graham Brighton)
5. 10:04 PM - Re: KIS TRI Nose Leg (Larry David)
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Subject: | Re: Here's an odd question |
4/15/2010
Hello Mike, You wrote: "Not sure why this (altitude variation with airspeed)
would be, or more importantly, how to fix it."
Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
This is not a very rare or mysterious phenomena. Inaccurate airspeed
indications can be caused by inaccurate dynamic and static air pressure
forces. Inaccurate altitude indications can be caused by inaccurate static
pressure forces.
AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
airspeed indicator is a balancing mechanism. It balances the difference
between a force created by dynamic air pressure and a force created by
static air pressure. The force from the dynamic air pressure is the result
of the forward movement of the airplane. The faster the airplane moves the
greater the force exerted.
In order to get an accurate measure of that dynamic force one needs to
accurately sense the free stream dynamic air pressure and send it to the
airspeed indicator via leak and kink free tubing. That means sensing the air
movement in the actual direction that the airplane is moving and having that
air movement not affected by some local air flow direction change caused by
the airframe itself. This is why you sometimes see flight test airplanes
with a long boom sticking out forward with a small vane mechanism on the
front of it. This boom and vane mechanism, along with connecting tubing, is
a pitot tube system intended to accurately measure the force from the free
stream dynamic air pressure without any inaccuracies introduced by local
airframe air flow. See Note One below.
So much for the dynamic force side of the airspeed indicator balancing act,
what about the static force side? An accurate static force is provided by a
static port ideally located somewhere on the airframe such that it is
measuring the true static air pressure. But finding that ideal location and
making the perfect static port that does not introduce static air pressure
errors is not always so quick and easy. And what do we do if we discover
that the static port that we have installed is not producing accurate static
air pressure? See Note Two below.
ALTITUDE. An altimeter is also a balancing mechanism. It measures the
difference between the initial altitude setting of the altimeter mechanism
as compared to the static air pressure encountered by that same mechanism
while in flight and displays that difference in some lineal measurement
(usually in feet in our part of the world). If the static pressure provided
to the altimeter via the static port and the connecting tubing is in error
or changes with the airplane's airspeed, when the actual altitude is
constant, then the altimeter's altitude indication will be in error. And
what do we do if we discover that the static port that we have installed is
not producing accurate static air pressure? See Note Two below.
'OC' Says: "The best investment we can make is the effort to gather and
understand knowledge."
Note One: Why don't we use these long boom and vane type pitot tubes on our
experimental amateur built aircraft? Because the boom and vane would take a
terrific beating from people walking into them on the ground and because the
dynamic force errors introduced by the type of pitot tubes that we commonly
use are just not great enough to cause us concern. There is not very much we
can do about adjusting the force coming from dynamic air pressure other than
using a pitot tube located a sufficient distance from a disturbing piece of
airframe (usually the bottom surface of a wing) and avoiding a leak or kink
in the tubing going from the pitot tube to the airspeed indicator.
Note Two: So we have built our airplane, installed our static port(s), and
discovered that we are getting inaccurate airspeed and / or altitude
indications and decide to do something about it. We could just go on
installing new static ports in different locations, but that is a lot of
work and we are not assured of better results. So we should do just what the
big boy aerodynamic types do, we fudge or bandaid as needed to get the air
to give us the results that we want.
Let's say that the airspeed indicator is reading too high -- it says the
airplane is going faster than it really is. (See Note Three). The dynamic
air pressure side of the airspeed indicator is providing too much force in
the desired balancing act. How can we counteract that excess dynamic force?
We increase the static force being fed to the airspeed instrument by the
static port by installing a small wedge just aft of the opening on the
static port (thin edge of the wedge facing forward towards the hole). This
small wedge causes air to pile up and increase the static air pressure going
to the airspeed indicator (and also to the altimeter unless you have
provided separate static ports for the two instruments) and give us the
accurate force balance measurement that we want.
Let's say that the altimeter reading goes down 200 feet when you speed up 60
miles per hour (Mike, you did not say which direction your altitude was
changing with the changes in airspeed). This means that the static port is
feeding greater than static pressure as your airplane flies faster. How can
we reduce that undesired increase in static air pressure? We install a small
wedge in front of the hole in the static port (thin edge of the wedge facing
aft towards the hole) to shield it a bit from dynamic air pressure coming
from the front in order to get a more stable and accurate altitude reading.
How do we get the right size wedge facing the correct direction to get the
airspeed and altitude results that we want? The same way the big boys do:
TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
experimental, amateur built we are permitted to do just that -- experiment.
Note Three: So now we know how to tweak our static port(s) to give us
accurate airspeed and altitude information, but how do we know that the
airspeed and altitude information is inaccurate in the first place and
during our trial and error efforts how do we know when we have achieved the
accuracy that we are seeking? The answer to those two questions is not as
simple as one might first expect. I won't attempt to answer them here
because the answers are too big and complex to answer in this forum. What I
will suggest is that the reader google "accurate airspeed" and "accurate
altitude" and delve into those subjects to the level desired. Here is just
one source you will find:
http://gpsinformation.net/main/altitude.htm
Note Four: This is a personal view point. There are several methods
available for determining accurate true airspeed. Some rather elaborate --
some use GPS. Just google "accurate airspeed using GPS".
One thing that I've never quite understood regarding these methods is the
focus on precisely determining airspeed accuracy indication in the cruising
airspeed range. If I determine that my airspeed indicator shows 150 knots
indicated airspeed and I determine through some elaborate scheme that I am
actually only going 145 knots through the air what do I do with that
information? Being 5 nautical miles short of my destination after a one hour
flight is a trivial naviagation error contribution compared to all the other
error sources (such as heading, wind, and climb airspeed) that I have to
contend with and should overcome anyway by some means of real time enroute
navigation.
I think that if I were going to invest a lot of time and effort in
determining my exact airspeed error I would be inclined to do that
determination in the approach airspeed arena, not the cruising airspeed
arena. And even then I would not be obsessed with absolute airspeed
accuracy, I'd just want to know what number on the indicator gives me the
right kind of safe approach and landing time after time.
================================================
----- Original Message -----
From: <bwilder@tqci.net>
Cc: "mike mccann" <mvmccann@gmail.com>; "Pulsar builders"
<pulsar-builders@caseyk.org>
Sent: Thursday, April 15, 2010 9:18 AM
Subject: Re: Here's an odd question
>I noticed that the back half of the round washer where the static exits on
> the SR22 had the back half of it filed down so there was in effect a
> little shield protecting the static exit hole. ((Sorry about this
> description.)
>
> I asked the people at their booth why they did that. I think I attended
> four air shows before I found someone who was involved with the
> engineering of the system. The answer - - - - "That is what we had to do
> to make the system work right". There didn't seem to be any theory behind
> it. They indicated that they had to fiddle around to get it to behave the
> way they wanted. Maybe they were just trying to get rid of me.
>
> In any event, I did the same with mine and it works fine.
>
> Bernie Wilder
=============================================
>>
>> ----- Original Message -----
>> From: mike mccann
>> To: Pulsar builders
>> Sent: Thursday, April 15, 2010 5:06 AM
>> Subject: Here's an odd question
>>
>>
>> All,
>>
>> Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
>> changes in airspeed (altitude will change 100-200 feet with speed
>> changes of 60 mph).
>>
>> Has anyone ever heard of this. Not sure why this would be, or more
>> importantly, how to fix it.
>>
>> Many thanks,
>>
>> Mike
>>
>> Pulsar 1
>> N116Km
Message 2
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Subject: | Re: Here's an odd question |
Mike;
I ran into the same situation when I installed a Dynon Pitot tube and
installed new static ports. I had a fairly large indicated airspeed error.
My 1st step was to check the pitot/static lines for leaks and kinks. I found
a small leak and one kink. Once fixed, then I corrected the remaining error
(port position and airspeed indicator instrument error) just like OC stated
in his Note 2. I used trial and error on the size of the "wedge" behind the
static port until it was as accurate as I could get it at the approach
airspeed (90Kts) I normally use.
THEN I did a LONG series of true airspeed tests using a three heading GPS
method and created a Calibrated Airspeed chart for my airplane from 80Kts to
150Kts. Why did I do this? I DON'T KNOW! I just enjoyed doing it. :o)
It really isn't hard to do, just very time consuming, BUT, it gave me
reasons to fly other than just turning Avgas into noise.
Galin
N819PR
On Thu, Apr 15, 2010 at 3:57 PM, <bakerocb@cox.net> wrote:
>
> 4/15/2010
>
> Hello Mike, You wrote: "Not sure why this (altitude variation with
> airspeed) would be, or more importantly, how to fix it."
>
> Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
>
> This is not a very rare or mysterious phenomena. Inaccurate airspeed
> indications can be caused by inaccurate dynamic and static air pressure
> forces. Inaccurate altitude indications can be caused by inaccurate static
> pressure forces.
>
> AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
> airspeed indicator is a balancing mechanism. It balances the difference
> between a force created by dynamic air pressure and a force created by
> static air pressure. The force from the dynamic air pressure is the result
> of the forward movement of the airplane. The faster the airplane moves the
> greater the force exerted.
>
> In order to get an accurate measure of that dynamic force one needs to
> accurately sense the free stream dynamic air pressure and send it to the
> airspeed indicator via leak and kink free tubing. That means sensing the air
> movement in the actual direction that the airplane is moving and having that
> air movement not affected by some local air flow direction change caused by
> the airframe itself. This is why you sometimes see flight test airplanes
> with a long boom sticking out forward with a small vane mechanism on the
> front of it. This boom and vane mechanism, along with connecting tubing, is
> a pitot tube system intended to accurately measure the force from the free
> stream dynamic air pressure without any inaccuracies introduced by local
> airframe air flow. See Note One below.
>
> So much for the dynamic force side of the airspeed indicator balancing act,
> what about the static force side? An accurate static force is provided by a
> static port ideally located somewhere on the airframe such that it is
> measuring the true static air pressure. But finding that ideal location and
> making the perfect static port that does not introduce static air pressure
> errors is not always so quick and easy. And what do we do if we discover
> that the static port that we have installed is not producing accurate static
> air pressure? See Note Two below.
>
> ALTITUDE. An altimeter is also a balancing mechanism. It measures the
> difference between the initial altitude setting of the altimeter mechanism
> as compared to the static air pressure encountered by that same mechanism
> while in flight and displays that difference in some lineal measurement
> (usually in feet in our part of the world). If the static pressure provided
> to the altimeter via the static port and the connecting tubing is in error
> or changes with the airplane's airspeed, when the actual altitude is
> constant, then the altimeter's altitude indication will be in error. And
> what do we do if we discover that the static port that we have installed is
> not producing accurate static air pressure? See Note Two below.
>
> 'OC' Says: "The best investment we can make is the effort to gather and
> understand knowledge."
>
> Note One: Why don't we use these long boom and vane type pitot tubes on our
> experimental amateur built aircraft? Because the boom and vane would take a
> terrific beating from people walking into them on the ground and because the
> dynamic force errors introduced by the type of pitot tubes that we commonly
> use are just not great enough to cause us concern. There is not very much we
> can do about adjusting the force coming from dynamic air pressure other than
> using a pitot tube located a sufficient distance from a disturbing piece of
> airframe (usually the bottom surface of a wing) and avoiding a leak or kink
> in the tubing going from the pitot tube to the airspeed indicator.
>
> Note Two: So we have built our airplane, installed our static port(s), and
> discovered that we are getting inaccurate airspeed and / or altitude
> indications and decide to do something about it. We could just go on
> installing new static ports in different locations, but that is a lot of
> work and we are not assured of better results. So we should do just what the
> big boy aerodynamic types do, we fudge or bandaid as needed to get the air
> to give us the results that we want.
>
> Let's say that the airspeed indicator is reading too high -- it says the
> airplane is going faster than it really is. (See Note Three). The dynamic
> air pressure side of the airspeed indicator is providing too much force in
> the desired balancing act. How can we counteract that excess dynamic force?
> We increase the static force being fed to the airspeed instrument by the
> static port by installing a small wedge just aft of the opening on the
> static port (thin edge of the wedge facing forward towards the hole). This
> small wedge causes air to pile up and increase the static air pressure going
> to the airspeed indicator (and also to the altimeter unless you have
> provided separate static ports for the two instruments) and give us the
> accurate force balance measurement that we want.
>
> Let's say that the altimeter reading goes down 200 feet when you speed up
> 60 miles per hour (Mike, you did not say which direction your altitude was
> changing with the changes in airspeed). This means that the static port is
> feeding greater than static pressure as your airplane flies faster. How can
> we reduce that undesired increase in static air pressure? We install a small
> wedge in front of the hole in the static port (thin edge of the wedge facing
> aft towards the hole) to shield it a bit from dynamic air pressure coming
> from the front in order to get a more stable and accurate altitude reading.
>
> How do we get the right size wedge facing the correct direction to get the
> airspeed and altitude results that we want? The same way the big boys do:
> TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
> experimental, amateur built we are permitted to do just that -- experiment.
>
> Note Three: So now we know how to tweak our static port(s) to give us
> accurate airspeed and altitude information, but how do we know that the
> airspeed and altitude information is inaccurate in the first place and
> during our trial and error efforts how do we know when we have achieved the
> accuracy that we are seeking? The answer to those two questions is not as
> simple as one might first expect. I won't attempt to answer them here
> because the answers are too big and complex to answer in this forum. What I
> will suggest is that the reader google "accurate airspeed" and "accurate
> altitude" and delve into those subjects to the level desired. Here is just
> one source you will find:
>
> http://gpsinformation.net/main/altitude.htm
>
> Note Four: This is a personal view point. There are several methods
> available for determining accurate true airspeed. Some rather elaborate --
> some use GPS. Just google "accurate airspeed using GPS".
>
> One thing that I've never quite understood regarding these methods is the
> focus on precisely determining airspeed accuracy indication in the cruising
> airspeed range. If I determine that my airspeed indicator shows 150 knots
> indicated airspeed and I determine through some elaborate scheme that I am
> actually only going 145 knots through the air what do I do with that
> information? Being 5 nautical miles short of my destination after a one hour
> flight is a trivial naviagation error contribution compared to all the other
> error sources (such as heading, wind, and climb airspeed) that I have to
> contend with and should overcome anyway by some means of real time enroute
> navigation.
>
> I think that if I were going to invest a lot of time and effort in
> determining my exact airspeed error I would be inclined to do that
> determination in the approach airspeed arena, not the cruising airspeed
> arena. And even then I would not be obsessed with absolute airspeed
> accuracy, I'd just want to know what number on the indicator gives me the
> right kind of safe approach and landing time after time.
>
> ================================================
>
> ----- Original Message ----- From: <bwilder@tqci.net>
> To: "Keith Palmer" <kdpalmer@mweb.co.za>
> Cc: "mike mccann" <mvmccann@gmail.com>; "Pulsar builders" <
> pulsar-builders@caseyk.org>
> Sent: Thursday, April 15, 2010 9:18 AM
> Subject: Re: Here's an odd question
>
>
> I noticed that the back half of the round washer where the static exits on
>> the SR22 had the back half of it filed down so there was in effect a
>> little shield protecting the static exit hole. ((Sorry about this
>> description.)
>>
>> I asked the people at their booth why they did that. I think I attended
>> four air shows before I found someone who was involved with the
>> engineering of the system. The answer - - - - "That is what we had to do
>> to make the system work right". There didn't seem to be any theory behind
>> it. They indicated that they had to fiddle around to get it to behave the
>> way they wanted. Maybe they were just trying to get rid of me.
>>
>> In any event, I did the same with mine and it works fine.
>>
>> Bernie Wilder
>>
>
> =============================================
>
>>
>>> ----- Original Message -----
>>> From: mike mccann
>>> To: Pulsar builders
>>> Sent: Thursday, April 15, 2010 5:06 AM
>>> Subject: Here's an odd question
>>>
>>>
>>> All,
>>>
>>> Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
>>> changes in airspeed (altitude will change 100-200 feet with speed
>>> changes of 60 mph).
>>>
>>> Has anyone ever heard of this. Not sure why this would be, or more
>>> importantly, how to fix it.
>>>
>>> Many thanks,
>>>
>>> Mike
>>>
>>> Pulsar 1
>>> N116Km
>>>
>>
>
>
Message 3
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Subject: | Re: Here's an odd question |
OC once again, great explanation.
I had an airspeed problem due to a tiny bug crawling into my pitot tube on a
150 I used to have. Solved that little problem by disconnecting the tubing
behind the instrument panel before the airspeed indicator and blowing with
my mouth. The little bug and his nest came flying out. Airspeed was
consistent again. Larry
----- Original Message -----
From: <bakerocb@cox.net>
Sent: Thursday, April 15, 2010 2:57 PM
Subject: KIS-List: Re: Here's an odd question
>
> 4/15/2010
>
> Hello Mike, You wrote: "Not sure why this (altitude variation with
> airspeed) would be, or more importantly, how to fix it."
>
> Hello Bernie, You wrote: "There didn't seem to be any theory behind it."
>
> This is not a very rare or mysterious phenomena. Inaccurate airspeed
> indications can be caused by inaccurate dynamic and static air pressure
> forces. Inaccurate altitude indications can be caused by inaccurate static
> pressure forces.
>
> AIRSPEED. Let's talk about inaccurate airspeed measurements first. An
> airspeed indicator is a balancing mechanism. It balances the difference
> between a force created by dynamic air pressure and a force created by
> static air pressure. The force from the dynamic air pressure is the result
> of the forward movement of the airplane. The faster the airplane moves the
> greater the force exerted.
>
> In order to get an accurate measure of that dynamic force one needs to
> accurately sense the free stream dynamic air pressure and send it to the
> airspeed indicator via leak and kink free tubing. That means sensing the
> air movement in the actual direction that the airplane is moving and
> having that air movement not affected by some local air flow direction
> change caused by the airframe itself. This is why you sometimes see flight
> test airplanes with a long boom sticking out forward with a small vane
> mechanism on the front of it. This boom and vane mechanism, along with
> connecting tubing, is a pitot tube system intended to accurately measure
> the force from the free stream dynamic air pressure without any
> inaccuracies introduced by local airframe air flow. See Note One below.
>
> So much for the dynamic force side of the airspeed indicator balancing
> act, what about the static force side? An accurate static force is
> provided by a static port ideally located somewhere on the airframe such
> that it is measuring the true static air pressure. But finding that ideal
> location and making the perfect static port that does not introduce static
> air pressure errors is not always so quick and easy. And what do we do if
> we discover that the static port that we have installed is not producing
> accurate static air pressure? See Note Two below.
>
> ALTITUDE. An altimeter is also a balancing mechanism. It measures the
> difference between the initial altitude setting of the altimeter mechanism
> as compared to the static air pressure encountered by that same mechanism
> while in flight and displays that difference in some lineal measurement
> (usually in feet in our part of the world). If the static pressure
> provided to the altimeter via the static port and the connecting tubing is
> in error or changes with the airplane's airspeed, when the actual altitude
> is constant, then the altimeter's altitude indication will be in error.
> And what do we do if we discover that the static port that we have
> installed is not producing accurate static air pressure? See Note Two
> below.
>
> 'OC' Says: "The best investment we can make is the effort to gather and
> understand knowledge."
>
> Note One: Why don't we use these long boom and vane type pitot tubes on
> our experimental amateur built aircraft? Because the boom and vane would
> take a terrific beating from people walking into them on the ground and
> because the dynamic force errors introduced by the type of pitot tubes
> that we commonly use are just not great enough to cause us concern. There
> is not very much we can do about adjusting the force coming from dynamic
> air pressure other than using a pitot tube located a sufficient distance
> from a disturbing piece of airframe (usually the bottom surface of a wing)
> and avoiding a leak or kink in the tubing going from the pitot tube to the
> airspeed indicator.
>
> Note Two: So we have built our airplane, installed our static port(s), and
> discovered that we are getting inaccurate airspeed and / or altitude
> indications and decide to do something about it. We could just go on
> installing new static ports in different locations, but that is a lot of
> work and we are not assured of better results. So we should do just what
> the big boy aerodynamic types do, we fudge or bandaid as needed to get the
> air to give us the results that we want.
>
> Let's say that the airspeed indicator is reading too high -- it says the
> airplane is going faster than it really is. (See Note Three). The dynamic
> air pressure side of the airspeed indicator is providing too much force in
> the desired balancing act. How can we counteract that excess dynamic
> force? We increase the static force being fed to the airspeed instrument
> by the static port by installing a small wedge just aft of the opening on
> the static port (thin edge of the wedge facing forward towards the hole).
> This small wedge causes air to pile up and increase the static air
> pressure going to the airspeed indicator (and also to the altimeter unless
> you have provided separate static ports for the two instruments) and give
> us the accurate force balance measurement that we want.
>
> Let's say that the altimeter reading goes down 200 feet when you speed up
> 60 miles per hour (Mike, you did not say which direction your altitude was
> changing with the changes in airspeed). This means that the static port is
> feeding greater than static pressure as your airplane flies faster. How
> can we reduce that undesired increase in static air pressure? We install a
> small wedge in front of the hole in the static port (thin edge of the
> wedge facing aft towards the hole) to shield it a bit from dynamic air
> pressure coming from the front in order to get a more stable and accurate
> altitude reading.
>
> How do we get the right size wedge facing the correct direction to get the
> airspeed and altitude results that we want? The same way the big boys do:
> TRIAL AND ERROR and MORE TRIAL AND ERROR. Because our airplanes are
> experimental, amateur built we are permitted to do just that --
> experiment.
>
> Note Three: So now we know how to tweak our static port(s) to give us
> accurate airspeed and altitude information, but how do we know that the
> airspeed and altitude information is inaccurate in the first place and
> during our trial and error efforts how do we know when we have achieved
> the accuracy that we are seeking? The answer to those two questions is not
> as simple as one might first expect. I won't attempt to answer them here
> because the answers are too big and complex to answer in this forum. What
> I will suggest is that the reader google "accurate airspeed" and "accurate
> altitude" and delve into those subjects to the level desired. Here is just
> one source you will find:
>
> http://gpsinformation.net/main/altitude.htm
>
> Note Four: This is a personal view point. There are several methods
> available for determining accurate true airspeed. Some rather elaborate --
> some use GPS. Just google "accurate airspeed using GPS".
>
> One thing that I've never quite understood regarding these methods is the
> focus on precisely determining airspeed accuracy indication in the
> cruising airspeed range. If I determine that my airspeed indicator shows
> 150 knots indicated airspeed and I determine through some elaborate scheme
> that I am actually only going 145 knots through the air what do I do with
> that information? Being 5 nautical miles short of my destination after a
> one hour flight is a trivial naviagation error contribution compared to
> all the other error sources (such as heading, wind, and climb airspeed)
> that I have to contend with and should overcome anyway by some means of
> real time enroute navigation.
>
> I think that if I were going to invest a lot of time and effort in
> determining my exact airspeed error I would be inclined to do that
> determination in the approach airspeed arena, not the cruising airspeed
> arena. And even then I would not be obsessed with absolute airspeed
> accuracy, I'd just want to know what number on the indicator gives me the
> right kind of safe approach and landing time after time.
>
> ================================================
>
> ----- Original Message -----
> From: <bwilder@tqci.net>
> To: "Keith Palmer" <kdpalmer@mweb.co.za>
> Cc: "mike mccann" <mvmccann@gmail.com>; "Pulsar builders"
> <pulsar-builders@caseyk.org>
> Sent: Thursday, April 15, 2010 9:18 AM
> Subject: Re: Here's an odd question
>
>
>>I noticed that the back half of the round washer where the static exits on
>> the SR22 had the back half of it filed down so there was in effect a
>> little shield protecting the static exit hole. ((Sorry about this
>> description.)
>>
>> I asked the people at their booth why they did that. I think I attended
>> four air shows before I found someone who was involved with the
>> engineering of the system. The answer - - - - "That is what we had to do
>> to make the system work right". There didn't seem to be any theory behind
>> it. They indicated that they had to fiddle around to get it to behave the
>> way they wanted. Maybe they were just trying to get rid of me.
>>
>> In any event, I did the same with mine and it works fine.
>>
>> Bernie Wilder
>
> =============================================
>>>
>>> ----- Original Message -----
>>> From: mike mccann
>>> To: Pulsar builders
>>> Sent: Thursday, April 15, 2010 5:06 AM
>>> Subject: Here's an odd question
>>>
>>>
>>> All,
>>>
>>> Utilizing a GPS, I've found that my altimeter in my Pulsar varies with
>>> changes in airspeed (altitude will change 100-200 feet with speed
>>> changes of 60 mph).
>>>
>>> Has anyone ever heard of this. Not sure why this would be, or more
>>> importantly, how to fix it.
>>>
>>> Many thanks,
>>>
>>> Mike
>>>
>>> Pulsar 1
>>> N116Km
>
>
>
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Subject: | KIS TRI Nose Leg |
G'Day guys,
Recently swapped out the Subaru engine (158hp )
for a Zero time 195hp Subaru in my KIS TRI ... Have had over Temp Oil
pressure probs ...but was thinking the engine was running in ok as Oil
Temp were coming down ..
However yesterday during another short test flt the Oil Pressure dropped
..and after an engine surge the engine quit dead ..
Landed 50mtr short of the Runway ...Damage is ..one smashed Prop Blade
and one Nose Gear leg ..
So LOOKING to ask if anyone can give me a lead to a replacement nose
gear Leg ..It has the Streamlined steel leg ... Even a lead onto the
Streamlined profile steel supply would be great as i could remake the
leg if i had a piece of the Streamlined Steel Stock .
Any help would be great
Graham Brighton
gbrighton@skymesh.com.au
Message 5
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Subject: | Re: KIS TRI Nose Leg |
Lyle Hendricks made mine and it was really strong. Lyle, I hope you are re
ading this and can respond to Graham. Larry
----- Original Message -----
From: Graham Brighton
To: Kis-List@matronics.com
Sent: Thursday, April 15, 2010 9:07 PM
Subject: KIS-List: KIS TRI Nose Leg
G'Day guys,
Recently swapped out the Subaru engine (158hp ) fo
r a Zero time 195hp Subaru in my KIS TRI ... Have had over Temp Oil pressu
re probs ...but was thinking the engine was running in ok as Oil Temp were
coming down ..
However yesterday during another short test flt the Oil Pressure dropped
.and after an engine surge the engine quit dead ..
Landed 50mtr short of the Runway ...Damage is ..one smashed Prop Blade an
d one Nose Gear leg ..
So LOOKING to ask if anyone can give me a lead to a replacement nose gear
Leg ..It has the Streamlined steel leg ... Even a lead onto the Streamlin
ed profile steel supply would be great as i could remake the leg if i had a
piece of the Streamlined Steel Stock .
Any help would be great
Graham Brighton
gbrighton@skymesh.com.au
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