Zero
angle of attack and they were lucky to be alive. Speed is mentioned in
the Albacore book form the Museum and/or Palomar’s 2nd
volume on the history of US subs…I can neither confirm nor deny the facts in
those texts.
The
standard design criteria for an airfoil-shaped rudder is to have 30% in
front of the rudder post for near balanced operation. I think your
logic is flawed in your concept for your rudders.
R/Jay
Respectfully,
Jay
K. Jeffries
Andros
Is., Bahamas
Talk
sense to a fool and he calls you foolish.
- Euripides (484 BC - 406 BC)
From:
owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Brent
Hartwig
Sent: Thursday, August 28, 2008 5:21 PM
To:
PSUBSorg
Subject: [PSUBS-MAILIST] U.S.S. Albacore Dive
Brakes
Hello
Ray,
Interesting information. Did they say at what angle of attack
they were when they deployed the braking flaps, or how fast they were going
at the time? The speed might of been left out because of it being
classified. Did it say any thing about whether of not all the flaps
opened up at the same time properly. If the flaps towards the bottom opened
up first they would make the sub point down very quickly.
I would
think that what ever direction you were heading, the brakes if designed and
functioning properly, would simply slow you down without changing your
heading. To simplify the braking flaps on my sub designs I'm only thinking
about having one on each side towards the back of the hull, or the two flaps
on each wing, one opening up and one down, or a totally new system installed
instead of a basic single rudder, like I have on my K-250.
The new
system would be used for steering and braking. It would basically consist of
two rudders about two feet apart or sandwiched together. Each rudder can
only rotate 90 degrees towards the side they are one, and are controlled
individually by a foot peddle that is just to control that one flap. This
way you can move one and steer or move both and brake and/or steer. This can
be a totally manual system, a partly manual system with a hydraulic assist
like used in a car, or fly by wire controlled hydraulic, electric, or
pneumatic actuator controlled. I'm designing a system like this to be
installed on my K-250
For the purely manual configuration the
steering/braking flaps need to have the pivot point back from the leading
edge a certain amount to help you in moving the flaps with the assist of the
water. My friend Doc, the inventor of the Bionic Dolphin told me how much it
should be, but at the moment I'm not able to locate the data. I think it was
about 30 percent surface area should be forward of the pivot point. They do
this sort of thing one the elevator of planes as well. But they don't look
to have as much as 30 percent.
Your
resident possibility thinker.
;)'
Regards,
Brent
Hartwig
-----------------------------------------------------------------------------------------------------------------------
Hi
Dean,
The U.S.S. Albacore had dive brakes around her circumference behind
the sail.
The book "U.S.S Albacore" by Robert P. Largess says on
pages 102 to 105 that they were a mistake. One time they were tried the sub
lost control and bottomed at 400 feet. Another time the brakes were to be
flapped to create an acoustical signal. A hydraulic seal failed and water
pressure force hydraulic fluid into the engine room.
The brakes were
immediately removed and were never tried again on another US
sub.
Regards,
Ray