Bronco Type XXIII in 1/35th scale

[redboat219]

Not sure if this is the same thing,https://www.google.com.ph/url?sa=t&s...50768961,d.aGc

[He Who Shall Not Be Named]

Maybe you need this, http://link.springer.com/chapter/10....-642-10690-3_8

Can you find a copy of that in English, Romel?

M

[redboat219]

Maybe you need this, http://link.springer.com/chapter/10....-642-10690-3_8

[redboat219]

Definitely need to get hold of a working 32nd Parallel XXIII and see how she's set up.

[He Who Shall Not Be Named]

Just got back from the Nauticus show. Put the Bronco 1/35 Type-23 in the water with the latest change -- an effort to correct the 'dive-of-doom' this model has exhibited since I first put it in the water over a month ago.

No improvement! Not one bit of difference! Damit! .... dive the boat, advance the throttle and I may have it for a few moments, but eventually the damned thing assumes a pronounced down angle and it just keeps going -- only recovery option is to go all back, emergency.

Damn!

I'm at a loss as to what to do.

M

[redboat219]

Hello David,

Is it possible that the bronco models lack of negative angle on the stern fins is causing the pitch problem? My old 32 parallel type 23 has negative angle moulded into the thin airfoil shaped fins in front of the stabilizer and this boat is stable at all speeds. Then again it is not fast! Most photos indicate this negative angle and the Fritz kohl plans also show it. Food for thought. Good luck.
Sincerely,

george

How many degrees negative incidence are we talking here?

[trout]

Take video......please. Oh and if I am not being too pushy some photos also.

[He Who Shall Not Be Named]

Hello David,

Is it possible that the bronco models lack of negative angle on the stern fins is causing the pitch problem? My old 32 parallel type 23 has negative angle moulded into the thin airfoil shaped fins in front of the stabilizer and this boat is stable at all speeds. Then again it is not fast! Most photos indicate this negative angle and the Fritz kohl plans also show it. Food for thought. Good luck.
Sincerely,

george

Don't know if the BRONCO Type-23 has the incidence on the stabilizers (actually their function is to act as cut-waters, protecting the control surfaces from contact damage) to scale with prototype or not. Drawings I've seen seem to have the cord of those surfaces parallel with the boats centerline. On the kit they are (both the fore and after sets) at a zero-degree incidence, which strikes me as proper.

Anyway ... after weeks of getting caught up on Caswell work, I took Darrin's advice and switched the angle-keeper to the bow planes and are now driving the stern planes manually -- only employing them as a set of trim surfaces. That's how Darrin got his Type-23 kit to perform underwater.

Tomorrow is the Elite Fleet's outing at the Norfolk Nauticus Coy ponds. I'll evaluate the new control set-up then and will report back on how it worked over the weekend.

M

[GNuge]

Hello David,

Is it possible that the bronco models lack of negative angle on the stern fins is causing the pitch problem? My old 32 parallel type 23 has negative angle moulded into the thin airfoil shaped fins in front of the stabilizer and this boat is stable at all speeds. Then again it is not fast! Most photos indicate this negative angle and the Fritz kohl plans also show it. Food for thought. Good luck.
Sincerely,

george

[He Who Shall Not Be Named]

Good point, and a real phenomena, but only occurs as a consequence of 'foil-roll'. The sail acting as a centerboard at a high angle-of attack, inducing the boat to roll into a tight turn. Big issue with high performance submarines -- but something compensated for by a good ship-control party: with little direction the planesman and helmsman will coordinate to put on some up plane to counter the pitch-down force produced by the rudders as they orient away from the vertical with the roll.

But, that's not the issue with the submerged tests with the 23. The pitch-down is occurring while going straight ahead. No turn, no foil-roll.

Good thinking though.

M

[GNuge]

My thoughts on your pitch control issue . Is it possible that the boat is leaning wh

[QUOTE=He Who Shall Not Be Named;28504]held up in the Cave catching up on purchase orders.

Sir, is it possible that your boat is leaning to one side or the other while turning at speed and the rudder is then acting similar to the stern planes to cause the boat to dive or rise depending upon which way it is leaning?

[He Who Shall Not Be Named]

held up in the Cave catching up on purchase orders.

M

[ffr2608]

This period of silence has me a bit worried.


D

[redboat219]

Curious,

In your previous post the c.g. is located in front of the sail. That's where i assume the center or rotation would also be located. So forces acting on the sail would cause the bow to pitch up not down.

[He Who Shall Not Be Named]

My never ending gratitude and one bucket of water-slug.

Tomorrow -- been too busy to try out your idea, Darrin. Can't wait.

M