Bow and stern planes control?

[robert f.]

Hi everyone,

I am currently building a sub which has both bow and stern dive planes. This is a first to me and I am wondering how to operate bow and stern planes simultaneously.

I know this issue has been addressed in the SCR a couple of years ago, but since I moved house a few months ago and have planned to move again within the next six to seven months, my submarine library is in storage (yes, I too keep all the back issues of the SCR in hard copy.....).

So that's why I'm asking here. What I would like to know is:
- do bow and stern dive planes (when operated simultaneously) work in the same direction or do they (as I seem to remember) countervail each other?
- can bow and stern planes be hooked up together on the same receiver channel?
- do bow and stern planes need two separate pitch controllers or can they be controlled by just the one?

I know these questions may overlap somewhat, but I just don't have the time now to formulate it more precise (and I am not an English native speaker, after all).

Any help and/or advice in this would be greatly appreciated.


Robert

[crazy ivan]

Robert,

We are leaving for SubRegatta

Robert,

We are leaving for SubRegatta 09 this morning, but could address all of your questions afterward. Meanwhile, check this thread for my comments on the interaction of bow and stern planes, about 3/4 the way down the page:

http://s181686668.onlinehome.us/phpBB2/viewtopic.php5?t=6098&start=0&postdays=0&postorder=asc&highlight=

[robert f.]

Hi George,

thanks for your quick

Hi George,

thanks for your quick reply!

I have read your contributions to the thread you referred to and a lot of my questions were answered right away. But they also raised a few new questions...

You may have noticed from my earlier postings that I'm building the Moebius Seaview. My plan is to combine Dave Welch's WTC with RCABS (Dave is currently working on it; keep it up Dave! ) with some elements from Merriman's/Caswell's Seaview fittings kit. For instance, both bow planes and sail planes will be functional.

I have a six-channel Robbe/Futaba F14 radio set (well, it's seven channels actually, but the seventh is an on/off switch only, to be used for the Seaview's lighting system), so I have some room for some extra functions and do some experimenting.

I like the idea of connecting the stern planes servo to just the APC, but not to a channel. How exactly do you do this? By not connecting the signal wire of the servo, so that the servo only gets its power from the receiver?

I am also thinking of connecting the bow planes to a separate ADC and using them for depth control. Would it be a good idea to hook bow and sail planes up to the same channel, since both would be used for depth control?

Regards,

Robert

[crazy ivan]

I'm glad you found my

I'm glad you found my comments helpful, Robert. Lots of folks get confused about the function of the bow and stern planes.

I like the idea of connecting the stern planes servo to just the APC, but not to a channel. How exactly do you do this? By not connecting the signal wire of the servo, so that the servo only gets its power from the receiver?
Robert

You almost have it. It's the signal pin to the APC that needs to be isolated from the receiver, then all the pins of the servo plug into the APC. Some connectors may allow you to push the signal pin out of the header so it can be taped out of the way. If not, you can make an adapter from a male and a female servo connector (my preference), or from a short servo extension cable. I would rather not cut the pin or the wire directly at the APC, because it may be desirable to plug the APC into a working channel at a later time. I did this when I upgraded from a 4 channel radio to an 8 channel one.

I am also thinking of connecting the bow planes to a separate ADC and using them for depth control. Would it be a good idea to hook bow and sail planes up to the same channel, since both would be used for depth control?
Robert

The Seaview is an oddball among submarines in this respect, Robert. Few other subs would ever have both bow and sail planes. Also, the Seaview's bow planes are unique in that they are so far removed from the center of gravity that they can in fact impart a rotational effect on the hull. As I mentioned in the other thread, it may actually be beneficial to link the bow and stern planes together, contrary to the normal wisdom, to counter the Seaview's tendency to nose down at speed. The sail planes should then be left by themselves to control depth.

[mike dory]

Controling the Seaview

Howdy - I would agree with Crazy Ivan, There is no other Sub like the Sea view real or model. I'd talk to the guys that have had success in making it work. That's what is great about going to a regatta you get to see what works best. However failing that, The guy that has built more working Seaview's then anyone, has to be David Merriman, He's the guy that I'd want to be talking to. You can find his ISP on the vendor's page. I've noticed a good number of Seaview models that have just become surface models. So I'm sure getting it to work well under water isn't for the faint of heart. I wish you all the best on your project..... Mike Dory

[junglelord]

I know that a way

I know that a way to counter the nose dive effect of the bulbous bow head is to have fixed vanes in the nicelles to counter the downward force at the bow.

I am making several Seaviews, I still need to order my Bigdave version.
My Bigdave version will be like Steve's, with only functional planes at the stern. I may add sailplanes too, not sure yet.

I am trying two of Merrimans. One fully functional, which is done, YEAH!
(held back due to financing my sons college)

I am ready now for the other one without the front bow planes. Both with have fixed vanes. I will let you know what the outcome is between all three subs at some point in the future.

[Guest]

Anyone tried weight/ballast shifting?

Very

Anyone tried weight/ballast shifting?

Very effective, especially at low speed, and cheap and straightforward to implement.

[junglelord]

Sounds good to me, and

Sounds good to me, and not that I know of...

[robert f.]

Thanks for all your responses

Thanks for all your responses gentlemen!

I think I'm almost there.

George, in the other thread, you indeed already mentioned the fact that Seaview is in a class of its own with both bow planes and sail planes. I agree that it is probably best not to link them and keep the sail planes for depth control only.

Mike, you're absolutely right, too]http://www.subcommittee.com/forum/icon_cry.gif[/img] But exchanging ideas and experiences through these forums is an excellent next-best solution, as all your responses clearly show.
As far as contacting Mr Merriman is concerned: I have ordered his instructional DVD's from Caswell's which should help considerably. Unfortunately, they are being delayed somewhat because of problems producing one of the DVD's, but I'm sure they will get here in the end. If they leave questions unanswered (which I rather doubt, given Mr. Merriman's thorough approach of things), I will contact him directly.

Junglelord, the idea of deflectors in the nacelles might also help, but I would prefer to try and tackle the problem at its origin, i.e. the bow, first. Thanks for your suggestion, though.

SubCulture, as far as I can judge at the moment, there is not enough room in the WTC for a weight/ballast shifting system. The same applies for outside the WTC....

So, to summarize, I am thinking of starting with this configuration: bow and stern planes functional, linked and connected to an APC, but not to a channel (the way George described), sail planes functional and linked to an ADC.

That leaves me with one more question. If I remember correctly, bow and stern planes work in opposite directions (when bow planes are in upward position, the stern planes are in downward position and vice versa). Am I right?

Regards,

Robert

[junglelord]

I know that Mr Merriman

I know that Mr Merriman suggest that the bow and stern planes be hooked in concert with the ADF for the Seaview as did Crazy Ivan, in a functional channel.

The fixed vanes help to compensate, and may totally correct the nose dive, or may not fully correct, it was hard to pin him down on that one...he seemed to go both ways, LOL. But it was his idea (Merrimans) in the first place and I will use it.

The DVD problem was what made them very upset with me....and its not my problem. So my shirt is clean.

Cheers to your build.

[redboat219]

Coanda Effect

What about using the Coanda Effect (http://en.wikipedia.org/wiki/Coanda_Effect)
as sort of a Circulation Control Wing (http://en.wikipedia.org/wiki/Circulation_control_wing)
on the Seaview's bow to negate the pitching down attitude induced by the manta rays during submerged running?

You could either use a small water pump or bleed off from the pumpjets to force water through slots on the top leading edge of the manta rays to produce lift.

[hakkikt]

If the pitch-down is really

If the pitch-down is really that bad (and from the shape of the bow I can believe it), there is probably no solution that works for all speeds. Whatever fixed vanes are installed, they will have more effect at high speeds due to hydrodynamics (=push the bow up stronger). This means that either the lift is optimised for low speeds, then there will be pitch-up at high speeds, or the lift is optimised for high speeds, then there will still be pitch-down at low speeds.
Looks to me like it will need movable diveplanes up front and a (second?) level controller.

[junglelord]

I know that Steve Neills

I know that Steve Neills Big Dave build runs very well without the bowplanes. He has some good video of it, in case it has not been seen, here it is....

Here is a build of this unit.

http://s181686668.onlinehome.us/phpBB2/viewtopic.php5?t=7973&start=0

Some excellent video of the sub in action.

http://www.youtube.com/watch?v=rmW4XZt1kt0

http://www.youtube.com/watch?v=GMIM6Ia_efs&NR=1

[junglelord]

I think that the Steve

I think that the Steve Neill approach is much more germain to the sub itself. With a Big Dave unit, I myself, would not make bow planes.

I would rather put the rear stern planes on the ADF, add the Fixed Vanes, and use the Sail Planes via the hand to change depth. If you think about the two ways to build this unit, I would take Steves approach. I would rather not cut the hull or bow planes, or even maybe go static sail planes like Steve did. Certainly functional Sail Planes are more cool.



If you do decide to go for the bow planes, this may help.
http://www.rcgroups.com/forums/showthre ... st12014758
Good luck and let us know how it goes.

Lighting the model is also a good addition to the journey.

[crazy ivan]

That leaves me with one

That leaves me with one more question. If I remember correctly, bow and stern planes work in opposite directions (when bow planes are in upward position, the stern planes are in downward position and vice versa). Am I right?

If by that you mean the bow planes are set to pull the bow up when the stern planes are set to push the tail down, then yes, that would be my understanding of how they would be coupled. A crude and highly exaggerated illustration would be something like this:

-----\--------------------/----

I personally do not intend to activate the bow planes on my Seaview. If I find that I have the nosedive problem, I will seek out an alternate solution (of which I have no idea at this time).