Is anyone out there designing a scale PBY Catalina?

"Tom Osmundson" wrote in message
om...

Pardon for the earlier triple post, connection was giving me fits...
snipped
kumaros wrote
I recall a French series of nature documentaries filmed in Patagonia
etc.
featuring a huge amphibian twin-engined aircraft, sort of a flying
combination of a house, a boat and an airplane. I wish I could find
the
name of the series.
Kumaros
It's all Greek to me

Oh shoot, can't find the bookmark. I know what you are talking about,
the Explorer by Hubert de Chevigny and Dean Wilson (Dean did the
Private Explorer that was like a single engine winnebago). It had a
pair of 300hp O-540's , grossed 8000 or so, big and boxy, was huge
inside. I think it topped out at 125 mph or kts, can't remember. The
photo I saw it was painted yellow. Gihugic for a pair of O-540's!

AhHa! didn't find the page I found way back when, but found a photo of
it at the bottom of this page...
http://fafagege.free.fr/html/eng/reves.htm

That's it!!! That's the yellow monster of a sea-plane that was featured in
the series. In a couple of "interior" (he, he) shots you could see the tube
fuselage and the insulation as well as the bamboo furniture. Now if I could
only remember the name of the series :-(
So, to come to your original post. Why could you not replicate or even
scale down this one instead of a Catalina?
Kumaros
It's all Greek to me
It's all Greek to me

That's it!!! That's the yellow monster of a sea-plane that was featured in
the series. In a couple of "interior" (he, he) shots you could see the tube
fuselage and the insulation as well as the bamboo furniture. Now if I could
only remember the name of the series :-(
So, to come to your original post. Why could you not replicate or even
scale down this one instead of a Catalina?
Kumaros
It's all Greek to me
It's all Greek to me

I suppose one could duplicate it but it's kinda draggy with many
external braces and slow (although one could clean up the design). I'm
sure it works great, but lacks that classic look a catilina has. I
believe when I had some specs of it, the empty to gross ratio wasn't
the greatest. I think it was 5000 empty 8000 gross. It is metal, I'm
looking at composite for corrosion resistance. But you could make a
composite version of it (and get a better empty to gross ratio), like
I want to do to the PBY.

Some advantages of the PBY design is having the wing on a pylon. This
gets the same wing area (with same aspect ratio) in a shorter span. It
gets the engines up higher, out of the spray. The engines are close
enough together SE operation is relatively easy. You can stand on top
of the fuse to open a cowling and check the oil or whatever. The
retractable floats add cool factor but also adds weight. But outrigger
floats can be smaller than inboard sponsons to do the same job.

Tom: In the outer Pacific islands you can get auto gas, diesel and if
there
is a runway jet fuel. But NO avgas.
BTW I know a guy that flew a Grumman something or other Goose? out in
the
Marshalls for awhile. He now is in Calif selling a strange fast
outrigger
sailboat.
Stu Fields

Thank you for that post, I would have never thought of fuel
availability to that extent. That is definitely an advantage for using
200 hp deltahawk diesels(can use diesel or Jet A).

"Richard Riley" wrote in message
...

On 11 Jun 2004 22:07:51 -0700, (Tom Osmundson)
wrote:

:
:I suppose one could duplicate it but it's kinda draggy with many
:external braces and slow (although one could clean up the design). I'm
:sure it works great, but lacks that classic look a catilina has. I
:believe when I had some specs of it, the empty to gross ratio wasn't
:the greatest. I think it was 5000 empty 8000 gross. It is metal, I'm
:looking at composite for corrosion resistance. But you could make a
:composite version of it (and get a better empty to gross ratio), like
:I want to do to the PBY.

Generally an amphib will have a horrible empty to gross ratio. The
hull has to be MUCH heavier than for an equivalent conventional
airplane. A friend once told me that to see if the hull is strong
enough, beat on it with a baseball bat. If it doesn't dent, it might
be strong enough to take a floating log just before liftoff without a
catastrophic failure.

I'm not sure if going to composite - and keeping the same kind of
impact resistance - will give you a lighter airframe.

One can see you've done your homework.
Now, going to the other side of the cold war ;-)
Look at what almost all aerobatic pilots are doing, abandoning the various
forms of Pitts and going to the Zlins and Yaks.
Perhaps a Soviet era "Caspian Monster" "Wing in Ground Effect" vehicle would
be suitable for you. With composite materials "glass epoxy over foam
sandwich" for corrosion resistance, insulation and strength, you could build
something in the line of the following:
See: http://aeroweb.lucia.it/~agretch/RAFAQ/WIG.html
or: http://www.popsci.com/popsci/aviatio...410266,00.html
Of course you could try to build this ;-)
http://home.swiftdsl.com.au/~vortexau/Page2.htm
Kumaros
It's all Greek to me

"Tom Osmundson" wrote in message
om...
That's it!!! That's the yellow monster of a sea-plane that was featured
in
the series. In a couple of "interior" (he, he) shots you could see the
tube
fuselage and the insulation as well as the bamboo furniture. Now if I
could
only remember the name of the series :-(
So, to come to your original post. Why could you not replicate or even
scale down this one instead of a Catalina?
Kumaros
It's all Greek to me
It's all Greek to me

I suppose one could duplicate it but it's kinda draggy with many
external braces and slow (although one could clean up the design). I'm
sure it works great, but lacks that classic look a catilina has. I
believe when I had some specs of it, the empty to gross ratio wasn't
the greatest. I think it was 5000 empty 8000 gross. It is metal, I'm
looking at composite for corrosion resistance. But you could make a
composite version of it (and get a better empty to gross ratio), like
I want to do to the PBY.

Some advantages of the PBY design is having the wing on a pylon. This
gets the same wing area (with same aspect ratio) in a shorter span. It
gets the engines up higher, out of the spray. The engines are close
enough together SE operation is relatively easy. You can stand on top
of the fuse to open a cowling and check the oil or whatever. The
retractable floats add cool factor but also adds weight. But outrigger
floats can be smaller than inboard sponsons to do the same job.

Tom: In the outer Pacific islands you can get auto gas, diesel and if
there
is a runway jet fuel. But NO avgas.
BTW I know a guy that flew a Grumman something or other Goose? out in
the
Marshalls for awhile. He now is in Calif selling a strange fast
outrigger
sailboat.
Stu Fields

Thank you for that post, I would have never thought of fuel
availability to that extent. That is definitely an advantage for using
200 hp deltahawk diesels(can use diesel or Jet A).

The CONCEPT of the Consolidated PBY was a very good one. Given the airfoils
and engines available in 1938, the execution wasn't too bad either. They
did the best they could with the materials they had to work with.

Creating a replica in composite materials would probably not save much if
any weight over metal but the impact strength of carbon-kevlar would be much
greater. I'd think that generally adopting the concept with changes
wherever the opportunity presented itself to improve the design would result
in a pretty cool aircraft.

Bill Daniels

"Richard Riley" wrote in message
...
On Sat, 12 Jun 2004 12:05:10 GMT, "Bill Daniels"
wrote:

:
:Creating a replica in composite materials would probably not save much if
:any weight over metal but the impact strength of carbon-kevlar would be
much
:greater. I'd think that generally adopting the concept with changes
:wherever the opportunity presented itself to improve the design would
result
:in a pretty cool aircraft.

Kevlar absorbs water, even after it's been laminated, up to almost
it's own weight. In that enviornment you'd find the hull getting
heavier and heavier. Carbon is worse in impact resistance than glass
- it's stiff, but brittle.

Glass *might* be better than aluminum in this application (fiberglass
canoes are scraped up after 30 years, aluminum ones are dented to
hell) but I wouldn't bet on a significant weight savings.

Really? I thought Kayaks have used Kevlar/carbon for impact resistance. I
have never head that Kevlar absorbs water.

Bill Daniels

Barnyard BOb - wrote:

http://www.beriev-usa.com

Hmmmm.
A veritable bargain?

The price for each aircraft is slightly less than 1 million dollars
after a negotiated BULK discount that the Chinese requested.

How about this then:

http://volition.chooseyouritem.com/a...8000/8487.html

Not much to be found on the internet about the Airshark I by Freedom
Master. They went out of business in the early '90's and the person with
the kit forsale mentioned above, sent me an info packet and video tape
about the plane, ages ago...

Airshark: The Business Side: Airshark-Is it Dead in
the Water?, Mar. 1991, p. 86 of Kitplanes.

:Creating a replica in composite materials would probably not save much if
:any weight over metal

Well, from what I hear, if you were to build an composite airplane
like an aluminum plane, often it does not save much weight.

but the impact strength of carbon-kevlar would be
much
:greater. I'd think that generally adopting the concept with changes
:wherever the opportunity presented itself to improve the design would
result
:in a pretty cool aircraft.

Kevlar absorbs water, even after it's been laminated, up to almost
it's own weight. In that enviornment you'd find the hull getting

heavier and heavier. Carbon is worse in impact resistance than glass
- it's stiff, but brittle.

Correct, carbon isn't that great in the traditional sense of "impact
resistance", but there are many grades of carbon from many
manufacturers. For example, your fishing rod might say "IM-6" or
"IM-7", those are two different grades of CF manufactured by an outfit
named Hercules. CF can be had in many forms ranging from intermediate
(IM), high (HM), and ultra high (UHM) modulus (stiffness) to high
strength (HS). Kevlar is more resiliant than CF (in terms of how much
energy can be absorbed without permanent deformation).

Kevlar can absorb water in a laminate, but all laminates are not the
same. You could try to make a water tank with a double layer of glass
(or CF or kevlar) built like you would a wing for a model airplane and
all could leak from pinholes. But your average fiberglass boat doesn't
leak from pinholes because of the the way they do the laminate. In
that way, the water absorbed I would think would be minimal, but I'm
no expert on composites (yet! ;-) ). MSE 404, engineering composites,
is next spring for me (even then I will have much to learn, one 3
credit class can't teach everything)...


Glass *might* be better than aluminum in this application (fiberglass
canoes are scraped up after 30 years, aluminum ones are dented to
hell) but I wouldn't bet on a significant weight savings.

Really? I thought Kayaks have used Kevlar/carbon for impact resistance. I
have never head that Kevlar absorbs water.

Bill Daniels

Now a CF part can take impact, but it depends a lot on how the CF is
used.

The CONCEPT of the Consolidated PBY was a very good one. Given the
airfoils
and engines available in 1938, the execution wasn't too bad either.
They
did the best they could with the materials they had to work with.

Yep, for the mid 30's, they did a pretty darn good job.
And I'm sure that is part of the reason why you still see them in use
today!

Again, thanks for the comments!

Tom

Dan

My good buddy (now deceased) who flew 'Cats', told me 90, 90, 90.

Big John (Out of the hospital and kind of back with the living)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~```


On 10 Jun 2004 22:14:55 GMT, (B2431) wrote:

From: "John Oliveira"


PBY was only US warplane (not counting single engine observation) that did
not have flaps!
"Tom Osmundson"

The running gag at the tim was that the Cat had a take off speed of 100 kt,
cruise speed of 100kt and a stall speed of 100kt.

Dan, U.S. Air Force, retired

From: Big John
Date: 6/17/2004 2:49 PM Central Daylight Time
Message-id:

Dan

My good buddy (now deceased) who flew 'Cats', told me 90, 90, 90.

Big John (Out of the hospital and kind of back with the living)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~` ``


On 10 Jun 2004 22:14:55 GMT, (B2431) wrote:

From: "John Oliveira"


PBY was only US warplane (not counting single engine observation) that did
not have flaps!
"Tom Osmundson"

The running gag at the tim was that the Cat had a take off speed of 100 kt,
cruise speed of 100kt and a stall speed of 100kt.

Dan, U.S. Air Force, retired

I bow to his eperience.

Dan, U.S. Air Force, retired

Yea, I've herd that before... 90kts is best climb, best cruise speed
for range, and something else...

Big John wrote in message . ..
Dan

My good buddy (now deceased) who flew 'Cats', told me 90, 90, 90.

Big John (Out of the hospital and kind of back with the living)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~```


On 10 Jun 2004 22:14:55 GMT, (B2431) wrote:

From: "John Oliveira"


PBY was only US warplane (not counting single engine observation) that did
not have flaps!
"Tom Osmundson"

The running gag at the tim was that the Cat had a take off speed of 100 kt,
cruise speed of 100kt and a stall speed of 100kt.

Dan, U.S. Air Force, retired