Re: [PSUBS-MAILIST] new to the list

["Cliff Redus" <dr_redus@devtex.net>]

Mike, for propulsion, I am using the drive train and impellor and nozzle
from a Sea Doo XP jet ski.  The screw is a three blade axial flow single
stage pump that is bolted in a frame in the aft of the boat.  For yaw
control, this gives me +/- 26 degrees of rotation and +/- 8 degrees for
pitch control.  For submerged operation, I am driving the unit with 20 HP dc
motor connected to 120 VDC controlled by a Curtise PMC model 1221C-7401
Transistor Motor Controller.  With a POT this enables me to vary the speed
of the motor and jet pump from 0 to max rmp or even reverse the motor though
in my case, I am not planning on doing this.  The speed range on this motor
matches the rather high shaft rpms needed by the jet pump.  On the surface,
I am driving the jet ski impellor with a Rotax 787, two-stroke engine that
puts up 110 hp.  I know that using a two-stroke engine is a bit
controversial for psubers but I could not find a marine diesel with the
power to weight ratio I was looking for.  I could not stand the weight  of a
marine diesel for this boat size. It would have caused me to increase the
overall size of the boat which in turn would cause more drag.  To address
the safety issue (gas fumes), I am connecting exhaust and intake manifolds
directly to hull penetrations on either side of the sail and I am also
planning on using a carbon monoxide sensor that will shut in the engine if
readings go abnormal.  At normal speeds this combination of engine and motor
give a calculated 98 mile surface range and a 63 mile submerged range using
18 gals of fuel and a full charge on the batteries.  The batteries are
charged overnight with a BYCAN model BY-120/132/144-25A onboard battery
charger (for 120-144 volt battery packs).

Cliff




----- Original Message -----
From: "Michael Holt" <mholt@richmond.edu>
To: <personal_submersibles@psubs.org>
Sent: Wednesday, March 13, 2002 5:40 PM
Subject: Re: [PSUBS-MAILIST] new to the list


> Alec Smyth wrote:
>
> > Oh my, that's one heck on an interesting design. Hats off Cliff, you've
got
> > a whole bagful of innovations. I can't make out the mechanism just ahead
of
> > the tail... is it some sort of actuated universal joint? Also, I
couldn't
> > see the propulsion, although you described it in the write-up.
>
> Wonderful concept, Cliff.
>
> Talk a bit more about the propulsion.  Is that a screw?  Or did
> I miss that part?
>
>
>
> Mike