An amphibian that sank?

[Flyingmonk]

http://www.divingservices.net/aircraft.jpg
http://www.divingservices.net/9bcess2.jpg

Anyone have the story behind this? Strange that a plane designed to
float, sank!

The Monk

[Steven P. McNicoll]

"Flyingmonk" > wrote in message
ups.com...
>
> http://www.divingservices.net/aircraft.jpg
> http://www.divingservices.net/9bcess2.jpg
>
> Anyone have the story behind this? Strange that a plane designed to
> float, sank!
>

Doesn't seem any stranger than a boat sinking. I believe they're designed
to float as well.

[Dudley Henriques]

"Flyingmonk" > wrote in message
ups.com...
> http://www.divingservices.net/aircraft.jpg
> http://www.divingservices.net/9bcess2.jpg
>
> Anyone have the story behind this? Strange that a plane designed to
> float, sank!
>
> The Monk

I could be wrong, but wasn't the Titanic designed to float?
:-)
DH

[grassStain]

"Flyingmonk" > wrote in message
ups.com...
> http://www.divingservices.net/aircraft.jpg
> http://www.divingservices.net/9bcess2.jpg
>
> Anyone have the story behind this? Strange that a plane designed to
> float, sank!

It broke the law . . . . Law of gravity

(and the law won)

[Grumman-581]

"Steven P. McNicoll" > wrote in message
ink.net...
> Doesn't seem any stranger than a boat sinking. I believe they're designed
> to float as well.

These days, smaller boats often have flotation chambers filled with a closed
cell type foam (e.g. styrofoam) so that in the even that they are filled
with water, they might still remain on the surface, dependent upon what else
might be loaded in the boat... It wasn't always that way though... I've
helped recover sunken boats before that sank after hitting logs and such and
knocking holes in their bottom... Larger boats aren't required to have this
sort of positive flotation though... Don't remember exactly at what length
the requirement no longer applies... Probably around 25-30 ft or so, I
guess... It's quite possible that amphibs don't have this sort of design in
them...

[Roy Smith]

In article >,
"Grumman-581" > wrote:

> "Steven P. McNicoll" > wrote in message
> ink.net...
> > Doesn't seem any stranger than a boat sinking. I believe they're designed
> > to float as well.
>
> These days, smaller boats often have flotation chambers filled with a closed
> cell type foam (e.g. styrofoam) so that in the even that they are filled
> with water, they might still remain on the surface, dependent upon what else
> might be loaded in the boat... It wasn't always that way though... I've
> helped recover sunken boats before that sank after hitting logs and such and
> knocking holes in their bottom... Larger boats aren't required to have this
> sort of positive flotation though... Don't remember exactly at what length
> the requirement no longer applies... Probably around 25-30 ft or so, I
> guess... It's quite possible that amphibs don't have this sort of design in
> them...

*23.751***Main float buoyancy.

(a) Each main float must have‹

(1) A buoyancy of 80 percent in excess of the buoyancy required by that
float to support its portion of the maximum weight of the seaplane or
amphibian in fresh water; and

(2) Enough watertight compartments to provide reasonable assurance that
the seaplane or amphibian will stay afloat without capsizing if any two
compartments of any main float are flooded.

(b) Each main float must contain at least four watertight compartments
approximately equal in volume.

[Grumman-581]

"Roy Smith" > wrote in message
...
> 23.751 Main float buoyancy.
>
> (a) Each main float must have<
>
> (1) A buoyancy of 80 percent in excess of the buoyancy required by that
> float to support its portion of the maximum weight of the seaplane or
> amphibian in fresh water; and
>
> (2) Enough watertight compartments to provide reasonable assurance that
> the seaplane or amphibian will stay afloat without capsizing if any two
> compartments of any main float are flooded.
>
> (b) Each main float must contain at least four watertight compartments
> approximately equal in volume.

I don't see anything in there that would require the supposedly watertight
compartments to still provide floatation in the event of them no longer
being watertight...

On a side note, I've heard that for emergency floats on offshore (oil rig)
helicopters, they often end up with the floats on the surface and the
helicopter suspended underneath it in the water..

[Morgans]

"Flyingmonk" > wrote in message
ups.com...
> http://www.divingservices.net/aircraft.jpg
> http://www.divingservices.net/9bcess2.jpg
>
> Anyone have the story behind this? Strange that a plane designed to
> float, sank!

You might be surprised how many recreational boats sink. There are dozens
of thing that can happen. Most common are drain plug left out/loose, seals
or hoses leaking and slowly filling the boat.
--
Jim in NC

[Roy Smith]

In article >,
"Grumman-581" > wrote:

> On a side note, I've heard that for emergency floats on offshore (oil rig)
> helicopters, they often end up with the floats on the surface and the
> helicopter suspended underneath it in the water..

One of the fundamental truths of boat design is that the center of gravity
has to be lower than the center of bouyancy. If it's not, then eventually
the boat (helicopter, whatever) will figure out how to turn itself over so
that it is.

[Morgans]

"Roy Smith" > wrote
>
> One of the fundamental truths of boat design is that the center of gravity
> has to be lower than the center of bouyancy. If it's not, then eventually
> the boat (helicopter, whatever) will figure out how to turn itself over so
> that it is.

Not completely true, but right to a degree.

In the case of a heli or plane on floats, the center
of gravity is way higher than the center of buoyancy,
and everything continues to work out OK.

In that case the center of gravity is between the
outer points of buoyancy. Like this:


GGG

BB BB

Then if it gets a little sideways, and the gravity
is on the outside of buoyancy, things will re-adjust.

GGG BB

BB

Ker-splash! Soon it is stable again, but
in a bad (g) way:

BB BB

GGG
--
Jim in NC

[Jim Macklin]

The only unsinkable boat I know about is the Boston Whaler
www.whaler.com which is made of two fiberglass shells bonded
together with the inside filled 100% with foamed in-place
resin that makes it one solid boat. They even can be cut
into sections and the still get you to shore with dry feet.

But aluminum floats don't work well with foam inside because
of corrosion between the foam and metal. A better solution
is to fill the compartments with ping-pong balls. They
displace water, don't weigh too much and can be removed for
inspection and corrosion control.


--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Morgans" > wrote in message
...
|
| "Flyingmonk" > wrote in message
|
ups.com...
| > http://www.divingservices.net/aircraft.jpg
| > http://www.divingservices.net/9bcess2.jpg
| >
| > Anyone have the story behind this? Strange that a plane
designed to
| > float, sank!
|
| You might be surprised how many recreational boats sink.
There are dozens
| of thing that can happen. Most common are drain plug left
out/loose, seals
| or hoses leaking and slowly filling the boat.
| --
| Jim in NC
|

[Roy Smith]

In article >,
"Morgans" > wrote:

> "Roy Smith" > wrote
> >
> > One of the fundamental truths of boat design is that the center of gravity
> > has to be lower than the center of bouyancy. If it's not, then eventually
> > the boat (helicopter, whatever) will figure out how to turn itself over so
> > that it is.
>
> Not completely true, but right to a degree.
>
> In the case of a heli or plane on floats, the center
> of gravity is way higher than the center of buoyancy,
> and everything continues to work out OK.
>
> In that case the center of gravity is between the
> outer points of buoyancy. Like this:
>
>
> GGG
>
> BB BB
>
> Then if it gets a little sideways, and the gravity
> is on the outside of buoyancy, things will re-adjust.
>
> GGG BB
>
> BB
>
> Ker-splash! Soon it is stable again, but
> in a bad (g) way:
>
> BB BB
>
> GGG

Exactly. The heli has indeed figured out how to turn itself over and put
its CG below its CB.

[Peter Dohm]

> The only unsinkable boat I know about is the Boston Whaler
> www.whaler.com which is made of two fiberglass shells bonded
> together with the inside filled 100% with foamed in-place
> resin that makes it one solid boat. They even can be cut
> into sections and the still get you to shore with dry feet.
>
> But aluminum floats don't work well with foam inside because
> of corrosion between the foam and metal. A better solution
> is to fill the compartments with ping-pong balls. They
> displace water, don't weigh too much and can be removed for
> inspection and corrosion control.
>
>
> --
> James H. Macklin
> ATP,CFI,A&P
>
Some of the small sail boats also have foam filled compartments with the
same effect. The name MacGreggor comes to mind from years ago, and there
are probably others by now.

Peter

[John Kimmel]

Roy Smith wrote:
>
> One of the fundamental truths of boat design is that the center of gravity
> has to be lower than the center of bouyancy. If it's not, then eventually
> the boat (helicopter, whatever) will figure out how to turn itself over so
> that it is.

Absolutly wrong. The center of bouyancy of most large boats and ships
is well below the center of gravity.

--
John (I Took Naval Science) Kimmel


GET YER STINKING PAWS OFF ME YOU DAMN DIRTY APE!

[Roy Smith]

"Peter Dohm" > wrote:
> Some of the small sail boats also have foam filled compartments with the
> same effect. The name MacGreggor comes to mind from years ago, and there
> are probably others by now.

Barf. Never use "MacGregor" and "sailboat" in the same sentence. They are
the most butt-ugly things in the universe.

[Flyingmonk]

John Kimmel wrote:
> Roy Smith wrote:
> >
> > One of the fundamental truths of boat design is that the center of gravity
> > has to be lower than the center of bouyancy. If it's not, then eventually
> > the boat (helicopter, whatever) will figure out how to turn itself over so
> > that it is.
>
> Absolutly wrong. The center of bouyancy of most large boats and ships
> is well below the center of gravity.
>
> --
> John (I Took Naval Science) Kimmel
>
>
> GET YER STINKING PAWS OFF ME YOU DAMN DIRTY APE!

I saw a head-on picture of a carrier and boy did it look top heavy...

The Monk
GET YER STINKING PAWS OFF ME YOU DAMN DIRTY HUMAN! ~ Panet of the Apes
II

[Peter Duniho]

"Grumman-581" > wrote in message
...
> "Roy Smith" > wrote in message
> ...
>> 23.751 Main float buoyancy.
>>
>> (a) Each main float must have<
>> [...]
>
> I don't see anything in there that would require the supposedly watertight
> compartments to still provide floatation in the event of them no longer
> being watertight...

There's not.

However, I have heard of seaplane owners who have done things like fill
their wings (or other easily accessed compartments) with ping-pong balls,
for this purpose.

Generally speaking though, seaplanes don't have any filler material, such as
styrofoam or what have you the way boats do. I think it's likely that this
is because, as light as styrofoam is, when you fill every empty space of an
airplane with it, that's still useful load you lose.

Of course, there are also the certification and maintenance issues as well.
The bottom line is, I believe, that it's much simpler to put a bunch of
lightweight filler material in a boat than in an airplane.

Pete

[Peter Dohm]

"Roy Smith" > wrote in message
...
> "Peter Dohm" > wrote:
> > Some of the small sail boats also have foam filled compartments with the
> > same effect. The name MacGreggor comes to mind from years ago, and
there
> > are probably others by now.
>
> Barf. Never use "MacGregor" and "sailboat" in the same sentence. They
are
> the most butt-ugly things in the universe.

They actually did have a replica of a 19th century pilot boat that I thought
was sort of neat, if less than practical, and commercially it was a dismal
failure. But I really don't like most of their competitors boats very much
either.

Peter

[Richard Lamb]

Morgans wrote:

> "Roy Smith" > wrote
> >
> > One of the fundamental truths of boat design is that the center of gravity
> > has to be lower than the center of bouyancy. If it's not, then eventually
> > the boat (helicopter, whatever) will figure out how to turn itself over so
> > that it is.
>
> Not completely true, but right to a degree.
>
> In the case of a heli or plane on floats, the center
> of gravity is way higher than the center of buoyancy,
> and everything continues to work out OK.
>
> In that case the center of gravity is between the
> outer points of buoyancy. Like this:
>
> GGG
>
> BB BB
>
> Then if it gets a little sideways, and the gravity
> is on the outside of buoyancy, things will re-adjust.
>
> GGG BB
>
> BB
>
> Ker-splash! Soon it is stable again, but
> in a bad (g) way:
>
> BB BB
>
> GGG
> --
> Jim in NC

Uh, Houston, we are in Stable -two.

[Richard Lamb]

Peter Dohm wrote:

> "Roy Smith" > wrote in message
> ...
> > "Peter Dohm" > wrote:
> > > Some of the small sail boats also have foam filled compartments with the
> > > same effect. The name MacGreggor comes to mind from years ago, and
> there
> > > are probably others by now.
> >
> > Barf. Never use "MacGregor" and "sailboat" in the same sentence. They
> are
> > the most butt-ugly things in the universe.
>
> They actually did have a replica of a 19th century pilot boat that I thought
> was sort of neat, if less than practical, and commercially it was a dismal
> failure. But I really don't like most of their competitors boats very much
> either.
>
> Peter

That must have been the 23 foot. Cute little ship.
Right down to the bow sprit.

I've been looking at a Catalina Capri 18.
Can't decide if it's too big, or too small, or just right...


Richard

[Morgans]

"Richard Lamb" > wrote

> Uh, Houston, we are in Stable -two.

Blurb - Blurble - glug-glug-glug!
:-))
--
Jim in NC

[Morgans]

"Richard Lamb" > wrote

> I've been looking at a Catalina Capri 18.
> Can't decide if it's too big, or too small, or just right...

For sailing on what water, and what kind of trips?
--
(Captain) Jim in NC <g>

[Flyingmonk]

Morgans wrote:
> "Richard Lamb" > wrote
>
> > I've been looking at a Catalina Capri 18.
> > Can't decide if it's too big, or too small, or just right...
>
> For sailing on what water, and what kind of trips?
> --
> (Captain) Jim in NC <g>

Young man... Don't you have school tomorrow? <g> ducking for cover...

Thw Monk

[Grumman-581]

"Flyingmonk" > wrote in message
ups.com...
> I saw a head-on picture of a carrier and boy did it look top heavy...

The point of no return on a carrier is about 15 degrees, if I remember
correctly... For one of the Spruance class destroyers, it's around 60
degrees... At full speed, a ship should be able to apply full rudder
deflection and not go past the point of no return... I knew a guy once who
said that he was on a DD that was pulling 55 degrees as it made it back to
Norfolk -- light fuel load, storm off the coast, etc... You basically have
to strap yourself to your rack to sleep...

[Morgans]

"Flyingmonk" > wrote
>
> Young man... Don't you have school tomorrow? <g> ducking for cover...

BITE ME ! ! ! <g>

Don't remind me!
--
Jim in NC

[DABEAR]

The aircraft could have been deliberately sunk for training. Or, it
might have hit debris in the water or a submerged object and received a
whole punched through the fuselage. Lastly, water pumps might have
failed causing it to sink gradually between pilot visits.

Of course, Captain Zoom is known to operate a U-Boat in the vicinity of
the EAA seaplane harbor in Wisconsin. Not that he torpedoed it or
anything. It probably smacked him in the periscope upon landing.

You know, the thing he looks down his nose at to watch USENET from in
the submarine's Conman tower...

[Richard Lamb]

Morgans wrote:

> "Richard Lamb" > wrote
>
> > Uh, Houston, we are in Stable -two.
>
> Blurb - Blurble - glug-glug-glug!
> :-))
> --
> Jim in NC

Apollo...

Stable 1 was flat on yer back.

Stable 2 is hanging nose down from the straps.

[Richard Lamb]

Grumman-581 wrote:

> "Flyingmonk" > wrote in message
> ups.com...
> > I saw a head-on picture of a carrier and boy did it look top heavy...
>
> The point of no return on a carrier is about 15 degrees, if I remember
> correctly... For one of the Spruance class destroyers, it's around 60
> degrees... At full speed, a ship should be able to apply full rudder
> deflection and not go past the point of no return... I knew a guy once who
> said that he was on a DD that was pulling 55 degrees as it made it back to
> Norfolk -- light fuel load, storm off the coast, etc... You basically have
> to strap yourself to your rack to sleep...

sleep?

Are you kidding?

[Richard Lamb]

Morgans wrote:

> "Flyingmonk" > wrote
> >
> > Young man... Don't you have school tomorrow? <g> ducking for cover...
>
> BITE ME ! ! ! <g>
>
> Don't remind me!
> --
> Jim in NC

->SMACK!<-

No sailing for you until your attitude imroves young man!

LoL!!!

Inland lakes mostly, but it could handle coasting in reasonable weather.
It's just too hot and humid at sea level...

There's a nice Catalina 22 near by also.
Real clean older boat. Nicely found.

That's only 4 feet more, but it's all in the middle!
Makes a difference launching and trailering.

I was thinking of an O'Day 17 Daysailer at first,
but I wouldn't want to camp out on a Daysailer at my age...

I think the Capri 18 is a pretty good compromise.
With a roller furling jib, it should sail single handed pretty easy.
Big enough to keep a fairly dry cockpit.

factory webpage:
http://www.catalinayachts.com/yachts.cfm?act=model&id=10

[Bob Moore]

Roy Smith wrote
> Barf. Never use "MacGregor" and "sailboat" in the same sentence.
> They are the most butt-ugly things in the universe.

But were not always so. I owned a 1976 MacGregor "Venture 25" that
was a very attractive small boat very similiar in appearance to the
O'Days and Catalinas of the same size.

Bob Moore

[Peter Dohm]

> The aircraft could have been deliberately sunk for training. Or, it
> might have hit debris in the water or a submerged object and received a
> whole punched through the fuselage. Lastly, water pumps might have
> failed causing it to sink gradually between pilot visits.
>
That last was really what I was wondering. If it didn't get much use, a few
loose rivets could be enough.

Peter

[Peter Dohm]

"Bob Moore" > wrote in message
. 121...
> Roy Smith wrote
> > Barf. Never use "MacGregor" and "sailboat" in the same sentence.
> > They are the most butt-ugly things in the universe.
>
> But were not always so. I owned a 1976 MacGregor "Venture 25" that
> was a very attractive small boat very similiar in appearance to the
> O'Days and Catalinas of the same size.
>
> Bob Moore
>
They were indeed pretty boats, although I never saw the inside of one.

Peter

[Peter Dohm]

"Richard Lamb" > wrote in message
...
>
>
> Peter Dohm wrote:
>
> > "Roy Smith" > wrote in message
> > ...
> > > "Peter Dohm" > wrote:
> > > > Some of the small sail boats also have foam filled compartments with
the
> > > > same effect. The name MacGreggor comes to mind from years ago, and
> > there
> > > > are probably others by now.
> > >
> > > Barf. Never use "MacGregor" and "sailboat" in the same sentence.
They
> > are
> > > the most butt-ugly things in the universe.
> >
> > They actually did have a replica of a 19th century pilot boat that I
thought
> > was sort of neat, if less than practical, and commercially it was a
dismal
> > failure. But I really don't like most of their competitors boats very
much
> > either.
> >
> > Peter
>
> That must have been the 23 foot. Cute little ship.
> Right down to the bow sprit.
>
> I've been looking at a Catalina Capri 18.
> Can't decide if it's too big, or too small, or just right...
>
>
> Richard
>
>
You're right, it was the 23 foot. At the time it was a standard catalog
item, although I don't recall ever physically touring one. The feature that
I must liked, besides the outward appearance, was the interior layout.
Rather than trying to advertise sleeping 5 or even 6 people, it had a nicely
arranged forward cabin for two and either one or two bunks mid ship--I've
forgotten the number; but in they old days, they would have been available
to the crew while the paying passengers used the captain's cabin.

The Capri 18 may very well be just right. It's big enough to go belowdecks
for a nap, or even overnight, but small enough to be easily handled and
trailered.

One caveat regarding my nautical advice: Not much experience, and a lot of
that was in Sunfish. OTOH, if one of those old 23 foot MacGreggors should
come my way at about the right time...

Peter

[Chris W]

Jim Macklin wrote:

>A better solution
>is to fill the compartments with ping-pong balls. They
>displace water, don't weigh too much and can be removed for
>inspection and corrosion control.
>
>
>
Didn't the "Myth Busters" sink a boat and try to float it again by
filling it with ping-pong balls? If I remember right something on the
boat broke, and all the ping-pong balls spilled out.


--
Chris W
KE5GIX

Gift Giving Made Easy
Get the gifts you want &
give the gifts they want
One stop wish list for any gift,
from anywhere, for any occasion!
http://thewishzone.com

[Newps]

Chris W wrote:
> Jim Macklin wrote:
>
>> A better solution is to fill the compartments with ping-pong balls.
>> They displace water, don't weigh too much and can be removed for
>> inspection and corrosion control.
>>
>>
>>
> Didn't the "Myth Busters" sink a boat and try to float it again by
> filling it with ping-pong balls? If I remember right something on the
> boat broke, and all the ping-pong balls spilled out.

They did that experiment on a sailboat they had sunk and it did in fact
bring the sailboat back to the surface.

[mark]

"Newps" > wrote in message
...
>
>
> Chris W wrote:
>> Jim Macklin wrote:
>>
>>> A better solution is to fill the compartments with ping-pong balls. They
>>> displace water, don't weigh too much and can be removed for inspection
>>> and corrosion control.
>>>
>>>
>> Didn't the "Myth Busters" sink a boat and try to float it again by
>> filling it with ping-pong balls? If I remember right something on the
>> boat broke, and all the ping-pong balls spilled out.
>
> They did that experiment on a sailboat they had sunk and it did in fact
> bring the sailboat back to the surface.

Well I remember from my younger days when canoe swamps not to worry about
it. We did a test of our own back then. We swamped it so the canoe was
completely filled with water, but upright. Then we started sending people
out there to hang on the side rail and use the canoe to keep their heads out
of the water. We wanted to know how many people it would take to send it to
the bottom, but we never found out. We ran out of space on the side rails
for more people to grab.

Now I strongly suspect that it would difficult if not impossible to do the
same thing with an anphib. They are designed to fly not swamp.

[Grumman-581]

"Richard Lamb" > wrote in message
...
> Inland lakes mostly, but it could handle coasting in reasonable weather.
> It's just too hot and humid at sea level...

You need one of the diesel powered air-conditioners...

[Morgans]

"Chris W" > wrote

> Didn't the "Myth Busters" sink a boat and try to float it again by filling
> it with ping-pong balls? If I remember right something on the boat broke,
> and all the ping-pong balls spilled out.

Yep, a hatch gave way, but they screwed a piece of plywood on it, and then
brought to the surface.
--
Jim in NC

[UltraJohn]

Flyingmonk wrote:

> http://www.divingservices.net/aircraft.jpg
> http://www.divingservices.net/9bcess2.jpg
>
> Anyone have the story behind this? Strange that a plane designed to
> float, sank!
>
> The Monk
So was the Titanic! ;-)

[Highflyer]

"Dudley Henriques" > wrote in message
link.net...
>
> "Flyingmonk" > wrote in message
> ups.com...
>> http://www.divingservices.net/aircraft.jpg
>> http://www.divingservices.net/9bcess2.jpg
>>
>> Anyone have the story behind this? Strange that a plane designed to
>> float, sank!
>>
>> The Monk
>
> I could be wrong, but wasn't the Titanic designed to float?
> :-)
> DH
>

As I recall it even had lots of watertight compartments designed so that you
could flood several of them and the Titanic would still float. Unsinkable,
they called it. After it sank, the Unsinkable title was transferred to
Molly Brown of Denver. :-)

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

[Robert Bonomi]

In article >,
John Kimmel > wrote:
>Roy Smith wrote:
>>
>> One of the fundamental truths of boat design is that the center of gravity
>> has to be lower than the center of bouyancy. If it's not, then eventually
>> the boat (helicopter, whatever) will figure out how to turn itself over so
>> that it is.
>
>Absolutly wrong.

Beg to differ. The only _truly_stable_ geometry is 'heavy side down, light
side up'.

One _can_ design craft with a secondary, 'meta-stable', mode that is
'heavy side up'. one of the simplest examples of which is a catamaran.

> The center of bouyancy of most large boats and ships
>is well below the center of gravity.

Which is why most large boats and ships, *when*sufficiently*provoked*,
_will_ turn turtle.

The proof that the 'normal' mode of such craft is _not_ stable is shown
by the fact that there is a far larger range of 'roll attitude' from which
the ship will go 'bottom up', than there is where it will return upright.
And, once a ship _does_ go over, it is very, *VERY* difficult to get it
back upright. Anybody who has sailed a small sailboat is well aware of this;
it is all too easy to tip it over, and *way* more difficult to get it back
upright.