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  #1  
Old June 2nd 08, 07:19 PM posted to rec.aviation.piloting
Ken S. Tucker
external usenet poster
 
Posts: 442
Default Ram air

On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:

On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.

Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!
  #2  
Old June 2nd 08, 08:00 PM posted to rec.aviation.piloting
Tina
external usenet poster
 
Posts: 500
Default Ram air

On Jun 2, 2:19 pm, "Ken S. Tucker" wrote:
On Jun 2, 10:13 am, Tina wrote:



On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:


On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.

Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post

Depending on trip length and winds aloft, we choose as high an
altitude as is reasonable without oxygen. Many of our trips are the
order of 500 nm. At the moment that's often 11000 feet east bound.
When we can no longer run 5k or 10ks, or find ourselves winded when
walking high in the mountains or have other evidence of physical
limitations (we do have access to high altitude chambers here) we'll
reduce that altitude.

From 12000 feet we are usually requesting lower when we're 45 minutes
from the airport. When traffic permits we like coming down at 300 feet
a minute!

Bertie's welcome to his bends: bends would be a problem if we were
going up really fast, but at 18000 feet atmospheric pressure is
reduced only by 50%. 12000 feet is probably a 10 psia atmosphere, and
I don't think there will be much outgassing with a difference of 5
psi, even if we went up fast (Mooneys are nice, but their climb time
to altitude is not remarkable!) I think for divers that would be like
coming up suddenly from maybe 10 feet down.

As is clear in this group, different people flight plan differently.
We choose high. There are less likely to be undisciplined pilots, or
those flying under VFR, at 10,000 or 12,000 than at 3000.
  #3  
Old June 4th 08, 03:56 PM posted to rec.aviation.piloting
Big John
external usenet poster
 
Posts: 310
Default Ram air

On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"
wrote:

On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:

On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.

Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!


************************************************** *

Ken

Have you ever talked to anyone who got the bends flying? I have
thousands of hours and never have.

I have gone to 43K+ and made supersonic dives to 10K +/- with no
problems.

I have cruised for hours at 30K cockpit pressure and no problems
during let down and landing.

Big John
  #4  
Old June 4th 08, 05:10 AM posted to rec.aviation.piloting
Ken S. Tucker
external usenet poster
 
Posts: 442
Default Ram air

On Jun 4, 7:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"



wrote:
On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:


On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.


Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!


************************************************** *

Ken

Have you ever talked to anyone who got the bends flying? I have
thousands of hours and never have.

I have gone to 43K+ and made supersonic dives to 10K +/- with no
problems.

I have cruised for hours at 30K cockpit pressure and no problems
during let down and landing.


Is Mt. Everest summit at ~29K?
You can get a quick overview here,
http://en.wikipedia.org/wiki/Decompression_sickness
Ken






Big John


  #5  
Old June 4th 08, 06:35 AM posted to rec.aviation.piloting,alt.alien.vampire.flonk.flonk.flonk,uk.rec.sailing,alt.sailing.asa,alt.usenet.kooks
Bertie the Bunyip[_25_]
external usenet poster
 
Posts: 3,735
Default Ram air

"Ken S. Tucker" wrote in
:

On Jun 4, 7:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"



wrote:
On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:


On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the
air filter as well, so we typically observe about a half inch
improvement in MP. That's in line with some of the other
numbers offered here.


I guess there's no free lunch. There is no way we want to have
an IO540 pull the airplane along, nor do we want the fuss with
turbo charging. The payback for our typical for real flight
mission is just not there. My thought was and is that if it
was something pretty obvious someone would have done it on a
homebuilt. Actually, knowing some of those guys, it does not
have to be obvious at all, they are really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so.
Isn't that a demand of, let's see, at 23 inches mp at sea level
that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about
is, let's see, about 200 cubic feet a minute, that's 40 cubic feet
of oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds
a minute, or say 20 pounds to get to a pleasantly high altitude.
Maybe that translates in to dewer weighing a total of 50 pounds
with liquid O2? But it would make 15 inches of MP look like 22 or
so as far as the engine is concerned. I better get back to my day
job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.


Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!


************************************************** *

Ken

Have you ever talked to anyone who got the bends flying? I have
thousands of hours and never have.

I have gone to 43K+ and made supersonic dives to 10K +/- with no
problems.

I have cruised for hours at 30K cockpit pressure and no problems
during let down and landing.


Is Mt. Everest summit at ~29K?
You can get a quick overview here,
http://en.wikipedia.org/wiki/Decompression_sickness
Ken


You're an idiot.


How's that kill file working out, BTW?

Bwsawahwhahwhahwhahwhahhw!



Bertie
  #6  
Old June 5th 08, 04:31 AM posted to rec.aviation.piloting
Tina
external usenet poster
 
Posts: 500
Default Ram air

On Jun 4, 10:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"



wrote:
On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:


On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.


Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!


************************************************** *

Ken

Have you ever talked to anyone who got the bends flying? I have
thousands of hours and never have.

I have gone to 43K+ and made supersonic dives to 10K +/- with no
problems.

I have cruised for hours at 30K cockpit pressure and no problems
during let down and landing.

Big John

John, for what it's worth, bends have to do with gas coming out of
solution in the blood, and would happen if pressure was reduced too
fast. Rapid descent in an airplane would increase pressure, explosive
decompression would decrease it. I don't dive so don't have
decompression tables at hand, but remember coming up from 34 feet in
water means going to two atmospheres pressure to one. Sudden
decompression from a 7000 foot cabin to a 30,000 foot actual attitude
is not as great a change in pressure. It's not comparing apples with
apples exactly, but changes in altitude are a lot less challenging in
terms of getting bends than diving. Divers are cautioned about flying
immediately after diving, it takes time for the dissolved gases to
come out of the blood -- too fast makes bubbles, and bubbles in joints
makes bends.
  #7  
Old June 4th 08, 06:33 AM posted to rec.aviation.piloting,alt.alien.vampire.flonk.flonk.flonk,uk.rec.sailing,alt.sailing.asa,alt.usenet.kooks
Bertie the Bunyip[_25_]
external usenet poster
 
Posts: 3,735
Default Ram air

"Ken S. Tucker" wrote in
:

On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:

On Jun 1, 4:39 pm, Tina wrote:


The induction port for the ram air on the m20J bypasses the air
filter as well, so we typically observe about a half inch
improvement in MP. That's in line with some of the other numbers
offered here.


I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is
just not there. My thought was and is that if it was something
pretty obvious someone would have done it on a homebuilt.
Actually, knowing some of those guys, it does not have to be
obvious at all, they are really creative designers.


Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so.
Isn't that a demand of, let's see, at 23 inches mp at sea level
that's 23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "


I see Tango 2 Denny has some interesting ideas.
Ken


Well, I think it's a dead issue for us. What is fun to think about
is, let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as
the engine is concerned. I better get back to my day job.


Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.

Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?


OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!


I double everyone up.


Bertie
 




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