Fine example of Tarver Engineering release for service

"John R. Copeland" wrote in message
...

"The CO" wrote in message
...

I'm not aware that pitot pressure (which is directly related to
airspeed)

You're just trying to be nice, aren't you, CO?

:^)

We all know the fudog's memory failed him this time.

Well, I thought the bit about a VSI using pitot was a bit, um, well,
wrong.

One thing -- The pitot pressure isn't "directly related to airspeed",
(and we know you meant IAS, not TAS).

One, sorry didn't mean 'directly' in the physics/math sense, only that
it
was the input for an ASI (compared to static pressure of course)
An airspeed indicator gives you Indicated Air Speed. Q.E.D.

(A TAS indicator can also give you a TAS readout as it can apply a
correction
for the density altitude, but IAS is what you base your flying on (as
opposed to nav).

The differential pressure is really related to the airspeed *squared*.

Yes.

The CO

Tarver Engineering wrote:


The sole reason for using a static port is so the guts can be removed from
the pitot tube, in order to improve reliability. A pitot port produces no
static pressure datum.


Just as an example, when the aircraft is sitting still on the ground -
airspeed = 0. Since the pitot and static ports are in the same state,
doesn't that imply that static pressure is present at the pitot port?

MAH

Rich Ahrens wrote:


Yes, those static ports are pretty unreliable! :-)

All those moving parts...

Yep, I've got a can of static port grease on the shelf next to my bottle
of horn fluid and the box of muffler bearings.

MAH

mah wrote:

Rich Ahrens wrote:


Yes, those static ports are pretty unreliable! :-)

All those moving parts...

Yep, I've got a can of static port grease on the shelf next to my bottle
of horn fluid and the box of muffler bearings.

MAH

....and the coil of shoreline, the bottle of propwash and the
paint for the last post?...
--

-Gord.

mah wrote:

Tarver Engineering wrote:


The sole reason for using a static port is so the guts can be removed from
the pitot tube, in order to improve reliability. A pitot port produces no
static pressure datum.


Just as an example, when the aircraft is sitting still on the ground -
airspeed = 0. Since the pitot and static ports are in the same state,
doesn't that imply that static pressure is present at the pitot port?

MAH

Sure it's there, but it's there only until the a/c starts to
move. It's then no longer 'static pressure' because it's been
raised by the ram effect of the movement.

That's why you now need a 'static port' to supply the static
pressure to use as a reference. Is it really that difficult to
see?!?
--

-Gord.

mah wrote in message ...
Rich Ahrens wrote:


Yes, those static ports are pretty unreliable! :-)

All those moving parts...

Yep, I've got a can of static port grease on the shelf next to my bottle
of horn fluid and the box of muffler bearings.

MAH

right next to a Splap in an as removed state

"mah" wrote in message
...

Just as an example, when the aircraft is sitting still on the ground -
airspeed = 0. Since the pitot and static ports are in the same state,
doesn't that imply that static pressure is present at the pitot port?

Sure, unless:
1) The aircraft is moving
2) The wind is blowing
3) Either 1) or 2)
4) Both 1) and 2)

At that point the pressure is no longer static - so you need a static
port.
IIRC in fact, for an aircraft to be certified for IFR it has to have an
alternate
static source *as well*. Pitot pressure ceases to be equal to static
pressure
once the air is in motion relative to the port.
Whether the air moves on its own or the plane moves
through it is irrelevant.

The CO

MAH

"Gord Beaman" wrote in message
...
mah wrote:

Just as an example, when the aircraft is sitting still on the
ground -
airspeed = 0. Since the pitot and static ports are in the same
state,
doesn't that imply that static pressure is present at the pitot port?

MAH

Sure it's there, but it's there only until the a/c starts to
move. It's then no longer 'static pressure' because it's been
raised by the ram effect of the movement.

That's why you now need a 'static port' to supply the static
pressure to use as a reference. Is it really that difficult to
see?!?

Apparently.

The CO

"mah" wrote in message
...
Rich Ahrens wrote:


Yes, those static ports are pretty unreliable! :-)

All those moving parts...

Yep, I've got a can of static port grease on the shelf next to my
bottle
of horn fluid and the box of muffler bearings.

Well the only tiny grain of truth in that statement is that a static
port can be occluded by a
foreign object. On the ground this can be something like an insect
setting up housekeeping
in it, in flight ice is probably the biggest risk factor. Since loss of
the static port will bugger up
3 basic flight instruments (altimeter, ASI and VSI) this is non-trivial.

The CO

"Gord Beaman" ) wrote in message . ..
mah wrote:

Tarver Engineering wrote:


The sole reason for using a static port is so the guts can be removed from
the pitot tube, in order to improve reliability. A pitot port produces no
static pressure datum.


Just as an example, when the aircraft is sitting still on the ground -
airspeed = 0. Since the pitot and static ports are in the same state,
doesn't that imply that static pressure is present at the pitot port?

MAH

Sure it's there, but it's there only until the a/c starts to
move. It's then no longer 'static pressure' because it's been
raised by the ram effect of the movement.

That's why you now need a 'static port' to supply the static
pressure to use as a reference. Is it really that difficult to
see?!?


where are the mud bees?