Is a static port a precision thing?

Being qualified in both the UH-1H/V and UH-60A, also currently flying the
UH-1, I beg to differ about the static port.

When the UH-1 went to roof mounted pitot system the static ports were
removed from the sides of the aircraft and are part of the pitot tube now.

The UH-60A with the wedge mounted pitot tubes are the same way.

It has been a long time since I flew the CH-47 and I am pretty sure they are
the same way except the static port hole is in the bottom of the nose
mounted tube.

Just my two cents and I am going to check with the flight instrument guys
the next time I am over at the flight facility.

Fred
"B2431" wrote in message
...

Folks - When I bought my Tcraft, all that existed of the static port
was a length of rubber tubing running parallel to the ram air port
(which was there). Do I need to terminate that piece of hose in a
static port of a precision size? - Mike

The only requirements for a static port is the hole(s) be flush to the
aircraft
such that there is no air forced in or sucked out by the local airflow in
flight. You don't want the hole too small or you will get lag when
changing
altitude. You may not ever notice the lag, but it's there. You don't want
it
too big or critters my think you built them a home.

The static ports on big aircraft such as C-130s have a salt shaker
appearance
and have half a dozen or so holes around .032". Helicopters like the H-1
and
H-60 don't have static ports. They leave the static holes on the ASI, VVI
and
altimiter open to cockpit pressure.

Aircraft Spruce sells a single hole port.

You want a smooth surface within a few inches of the port.

That's as complicated as they get


Good luck with your project.

Dan, U. S. Air Force, retired

On USAF UH-1P and UH-60A they were as I described when I worked on them.
The UH-60A may have changed over the years. I was in the first USAF unit to get
them.

Dan, U. S. Air Force, retired




Being qualified in both the UH-1H/V and UH-60A, also currently flying the
UH-1, I beg to differ about the static port.

When the UH-1 went to roof mounted pitot system the static ports were
removed from the sides of the aircraft and are part of the pitot tube now.

The UH-60A with the wedge mounted pitot tubes are the same way.

It has been a long time since I flew the CH-47 and I am pretty sure they are
the same way except the static port hole is in the bottom of the nose
mounted tube.

Just my two cents and I am going to check with the flight instrument guys
the next time I am over at the flight facility.

Fred
"B2431" wrote in message
...

Folks - When I bought my Tcraft, all that existed of the static port
was a length of rubber tubing running parallel to the ram air port
(which was there). Do I need to terminate that piece of hose in a
static port of a precision size? - Mike

The only requirements for a static port is the hole(s) be flush to the
aircraft
such that there is no air forced in or sucked out by the local airflow in
flight. You don't want the hole too small or you will get lag when
changing
altitude. You may not ever notice the lag, but it's there. You don't want
it
too big or critters my think you built them a home.

The static ports on big aircraft such as C-130s have a salt shaker
appearance
and have half a dozen or so holes around .032". Helicopters like the H-1
and
H-60 don't have static ports. They leave the static holes on the ASI, VVI
and
altimiter open to cockpit pressure.

Aircraft Spruce sells a single hole port.

You want a smooth surface within a few inches of the port.

That's as complicated as they get


Good luck with your project.

Dan, U. S. Air Force, retired

Why can't the military keep things simple?

Fred

"B2431" wrote in message
...
On USAF UH-1P and UH-60A they were as I described when I worked on them.
The UH-60A may have changed over the years. I was in the first USAF unit
to get
them.

Dan, U. S. Air Force, retired




Being qualified in both the UH-1H/V and UH-60A, also currently flying the
UH-1, I beg to differ about the static port.

When the UH-1 went to roof mounted pitot system the static ports were
removed from the sides of the aircraft and are part of the pitot tube
now.

The UH-60A with the wedge mounted pitot tubes are the same way.

It has been a long time since I flew the CH-47 and I am pretty sure they
are
the same way except the static port hole is in the bottom of the nose
mounted tube.

Just my two cents and I am going to check with the flight instrument guys
the next time I am over at the flight facility.

Fred
"B2431" wrote in message
...

Folks - When I bought my Tcraft, all that existed of the static port
was a length of rubber tubing running parallel to the ram air port
(which was there). Do I need to terminate that piece of hose in a
static port of a precision size? - Mike

The only requirements for a static port is the hole(s) be flush to the
aircraft
such that there is no air forced in or sucked out by the local airflow
in
flight. You don't want the hole too small or you will get lag when
changing
altitude. You may not ever notice the lag, but it's there. You don't
want
it
too big or critters my think you built them a home.

The static ports on big aircraft such as C-130s have a salt shaker
appearance
and have half a dozen or so holes around .032". Helicopters like the
H-1
and
H-60 don't have static ports. They leave the static holes on the ASI,
VVI
and
altimiter open to cockpit pressure.

Aircraft Spruce sells a single hole port.

You want a smooth surface within a few inches of the port.

That's as complicated as they get


Good luck with your project.

Dan, U. S. Air Force, retired

"Frederick Wilson" wrote:

Why can't the military keep things simple?

Fred
+++++++++++++++++++++++++++++

Duh...
Because there is no money in it.


Barnyard BOb - follow the money

Take a look at the Puzzle Palace aka the Pentagon. There are people there who
have no concept of reality.

Next, take a look at the aquistion process. There are no procedures for asking
contractors to keep things simple.

When we first aquired the UH-60A the Sikorski reps and brochures said that the
helicopter had been designed with "maintenance in mind." Despite the pretty
pictures in the brochures and the friendly reps no one ever said that meant
they intended to make life easy for us. My favourite example was the pitch bias
actuator. The PBA was a little box about 8 inches long, 2 inches thick and 4
inches wide. The PBA was mounted in the middle of the mixing unit and was a
bear to replace. It was perpetually failing and was ultimately eliminated with
no noticable change in handling.

Dan, U. S. Air Force, retired

I was going to say, I do not recall a PBA although there is a Pitch Boost
Actuator which does nothing but dampen the feedback in the pitch axis much
like a shock absorber. However the thing does no offensive work at all like
the collective boost actuator.

Fred

"B2431" wrote in message
...
Take a look at the Puzzle Palace aka the Pentagon. There are people there
who
have no concept of reality.

Next, take a look at the aquistion process. There are no procedures for
asking
contractors to keep things simple.

When we first aquired the UH-60A the Sikorski reps and brochures said that
the
helicopter had been designed with "maintenance in mind." Despite the
pretty
pictures in the brochures and the friendly reps no one ever said that
meant
they intended to make life easy for us. My favourite example was the pitch
bias
actuator. The PBA was a little box about 8 inches long, 2 inches thick and
4
inches wide. The PBA was mounted in the middle of the mixing unit and was
a
bear to replace. It was perpetually failing and was ultimately eliminated
with
no noticable change in handling.

Dan, U. S. Air Force, retired