Revell Type VII Build advice

[Avera]

I see, I was adjusting the forward planes not the rear when I was calibrating the ADF. So the proper way of setting the ADF Pitch Control under the included instructions (Number 1 and 2 in the ADF2 instruction guide) is use the knob on the transmitter (channel 6 - rear plane) and NOT the bow plane control. The #2 step in the guide says:

"Command full rise on the planes of your transmitter, and while holding full rise push and hold the setup button again until the flash pattern changes to a solid green."

So my next question is which way do I turn the channel 6 knob for full rise; clockwise or counter clockwise?

[trout]

Which way makes your stern planes cause your stern to rise?

[Avera]

I should have figured that out myself.

I have not connected the stern planes but judging by the movement of them, if they point down then the stern should rise, the opposite of the bow plane if my logic is correct. Just need to check which way the servo moves when the knob is turned.

I just realized that my problem was with definitions and the ADF2 instructions. Pitch control meant the stern plane when all along I thought if was referring to the bow plane which I control on the TX. Just a simple error and hours wasted.

Andrew

[alad61]

I found it helped to have all the tx to rx to servo settings set on your planes before you hook up & tune the adf.... and after several hours the temperment changes, the clarity of thinking slides and it looks like the whole thing is a against you... thats when you just walk away for a day or so. Well thats what I do (most of the time. LOL!! )

[Avera]

To help further clarify the operation of the planes in my meager mind, (please correct me if I am wrong) the idea is for the sub to rise and sink while maintaining a somewhat level trim. This is accomplished by having both the bow and stern planes operate in tandem to raise each respective end when you want the sub to surface and if you want the sub to submerge, both planes should work to lower each end at the same time. I presume that the bow planes have a larger surface area than the stern plane would give it more lift (up/down) than the stern planes thus giving the sub a bit of a nose up/down respective to the stern.

Although a quicker way to dive would be to first have the bow sink while rising the stern (greater dive angle) and hope that the stern/props does not break the surface.

Would it not be easier to have one servo that controls both the bow and stern plane together? Though the connecting rods might be a bit tricky to configure.

I like technology (ADF2), but simplicity trumps everytime.

[He Who Shall Not Be Named]

To help further clarify the operation of the planes in my meager mind, (please correct me if I am wrong) the idea is for the sub to rise and sink while maintaining a somewhat level trim. This is accomplished by having both the bow and stern planes operate in tandem to raise each respective end when you want the sub to surface and if you want the sub to submerge, both planes should work to lower each end at the same time. I presume that the bow planes have a larger surface area than the stern plane would give it more lift (up/down) than the stern planes thus giving the sub a bit of a nose up/down respective to the stern.

Although a quicker way to dive would be to first have the bow sink while rising the stern (greater dive angle) and hope that the stern/props does not break the surface.

Would it not be easier to have one servo that controls both the bow and stern plane together? Though the connecting rods might be a bit tricky to configure.

I like technology (ADF2), but simplicity trumps everytime.

What you describe involves close coordination between the bow and stern planesman -- not an easy task for one man, which is the situation we r/c sub Driver's are in. We delegate stern plane duties, to a high degree, to an angle-keeping device. This unloads us from that chore, so we can concentrate on depth management using the fairwater/sail/bow planes. We're still in the stern plane loop, but for the most part we leave it to the angle keep to keep the boat at a near zero pitch angle.

You described the, 'Simon Lake method' of depth control, or the 'even keel' approach. First promoted by Mr. Lake back in the early 1900's.

The 'John Holland method' of depth control, or the 'pitching hull' approach, is for radical depth changes. It employees the 'lift' generated by the hull as it's forced up or down to the water flow (angle-of-attack) by the planes ... the stern planes contributing the most moment to that endeavor.

What the rest of the world submarine operators do today is a bit of both: a transition between the 'pitching hull' and 'even keel' method, to suite speed and depth orders. At patrol depth or periscope depth, the stern planesman works to keep the boat at a zero angle, the fairwater/sail/bow planesman controls depth with his planes.

When slow, you go with Mr. Lake. When scooting around fast and maneuvering like a crazy man, go with Mr. Holland.

I've stood many watches at both sets of planes and helm on the TRUTTA. I was pretty good at it. And a good watch-section will drive the boat to the commanded depth without direction or thought as to what mode you'll use -- the stern planesman knows what the bow planesman is doing, and vice versa. Anticipation of what the boat WILL do, and what will happen when your Mate spins his wheel is the key. Experience is the teacher. Oh, and the Diving Officer? His job is to slam his coffee cup off the back of your head should you get out of sync with the ship control party. Oh, and I should mention, he'll tell you what angle to go for or not exceed.

Below a critical speed, when operating the planes in the pitching hull mode, you get into the 'Chinese planes' phenomena -- where the static stability of the boat overcomes the pitching force of the stern planes, and things go backwards on you.


... but, that's another story.

David

[Avera]

Quite a few years back I was at the Pearl Harbor exhibit in Oahu. There is a cutout section of a submarine hull. I had the honor and thrill of meeting two WWII submariners (one American and the other German) at the same time while reading over the exhibit. For the few minutes I had, they enlighten me with small war story bits and fear of depth charges. It was an amazing experience to have both sides standing next to each other at peace sharing a common bond and telling their tales.

[H2Ohaze]

I'm not a Navy guy, just a mechanical wannabe. But here is a load of stuff on subs, more than you need. Look at figure 7 esp to see bow and stern planes in action:

http://www.heiszwolf.com/subs/tech/tech01.html

Having a Holland sub model, I'm biased toward Mr Holland. Simon Lake put wheels on his submarines, and as time went on, merely made them retractable.Scuba Diving

[Kazzer]

Quite a few years back I was at the Pearl Harbor exhibit in Oahu. . I had the honor and thrill of meeting two WWII submariners (one American and the other German) at the same time while reading over the exhibit. For the few minutes I had, they enlighten me with small war story bits and fear of depth charges. It was an amazing experience to have both sides standing next to each other at peace sharing a common bond and telling their tales.

I know how you felt. I met quite a few of these WWII guys. I lived with one of them. I lived with his submariner friends and comrades.

I heard about the depth charges, I heard how the Jap planes strafed his boat. I saw the fear and I saw the resolve in his eyes. This man hated the Japs until the day he died. He was at the surrender of the Japs to the British at Singapore. He saw the way his countrymen were treated, and he experienced the relief that the hell was - at last - over.

I grew up with this, and it took a toll on us all. This man was my dad!

And you know what really ****es me off! That some (a few) think I know nothing about submarines!

[Avera]

Life throws us all types of ironies and each episode needs to be taken in its own context (like the expression walk a mile in one's shoe before you judge).

When I was much younger, I had enrolled to enter in OCS to hopefully become a submariner, took all the Navy tests and just had to complete my college. I screwed up with my school grants and did not finish college until years later. Perhaps an opportunity lost. Today I could have been captain of my own boat, but that is not how it worked out. Although I did get my Coast Guard Captain's license (6 pack) and retired as captain from law enforcement

Anyone who fought in earnest for my freedom has my utmost respect and admiration with a special fondness for those from WWII. Men and women from that era have a character that is absent on today's generations (integrity, resolve, honor and humility to name a few). Sorry to get off topic but your dad deserves a thankyou from me.

[Avera]

Thanks to Trout and David, I finally got the SD working as it should (it would help if the Setup Mode instructions for the ADF specified the planes you want the ADF to control vs the planes you actually control). For one last remark, the way I have setup the ADF, as I pitch the sub into a dive, the rear plane operate to level the sub so that the sub dives in a level fashion; Lake method. The same in surfacing, as I tilt the SD up simulating a a surface command on the bow planes the rear planes points downward rising the stern. If this is correct I should be set to begin trimming in the tub this weekend. I have already added some foam, although probably not enough. Is it better to add more foam to create a greater difference between the CG and the CB or reduce the weight in the keel basically achieving the same difference but with a lighter sub? The lead shot is held in place by the silicone adhesive remove I can easily remove.

Andrew

[trout]

It has been a long day, but something seems wrong. If you lift the aft end of the wtc the stern planes should go down ( to counter the upward motion) and conversely if the aft end is lowered the stern planes should take an up attitude. If it doesn't do this then the ADF will not keep the sub level. Are we saying the same thing differently?

[He Who Shall Not Be Named]

You got it right, Andrew.


Tom, you got it backwards .... get some sleep, pal!

Andrew: Rubber band the foam to the outside of the hull during initial trimming tasks -- shifting form inboard and permanently affixed in place with RTV adhesive once amount and position are determined.

Yes, the object of the game is to put as much weight low in the hull as you can counter with foam placed up high, but no higher than the designed waterline.

And your suggesting to make it clear which planes to put the ADF on is a good one -- I assumed everyone would know it's the stern planes ... and you know what they say about the word, ASSUME!


Use of an angle-keeper places control of the boats pitch in the 'even keel' (Simon Lake) mode of ship control. The angle-keeper cares not a bit what the boats depth is, it's oblivious of it. The angle-keeper only works to keep the moving submarine on or near a zero bubble angle through stern plane deflection.

David

[Avera]

Hi David,

The waterline on this sub is just above the saddle tanks below the upper vents along the side. Is that correct? My initial trimming (using the rubber bands) had the bow higher than the stern, almost too high. I have already added some foam to the inside where the ballast tanks are with some more towards the bow and stern. I will check this out and add more foam using the rubber bands to see where I need adjustments.

As for the trim with the ballast air removed, the sub should lie in the water with just the upper part (I guess about where the upper gun is mounted) of the conning tower sticking out?

Andrew

One other thing, those motors are very strong, I accidently tap the throttle while it was in the tub, and the sub nearly popped a wheely, like a speed boat taking off from dead stop. Granted I was not controlling any of the planes and the ADF was not functional at the time, but the two motor throw out a lot of trust.

[He Who Shall Not Be Named]

Hi David,

The waterline on this sub is just above the saddle tanks below the upper vents along the side. Is that correct? My initial trimming (using the rubber bands) had the bow higher than the stern, almost too high. I have already added some foam to the inside where the ballast tanks are with some more towards the bow and stern. I will check this out and add more foam using the rubber bands to see where I need adjustments.

As for the trim with the ballast air removed, the sub should lie in the water with just the upper part (I guess about where the upper gun is mounted) of the conning tower sticking out?

Andrew

One other thing, those motors are very strong, I accidently tap the throttle while it was in the tub, and the sub nearly popped a wheely, like a speed boat taking off from dead stop. Granted I was not controlling any of the planes and the ADF was not functional at the time, but the two motor throw out a lot of trust.

The black/gray demarcation line at the bow and stern IS the surface trim waterline. Shoot for that.

Submerged trim puts about 1/4 - 1/2" of the top of the fairwater above water. Works for me.

You bet they are. At the transmitter: dial your ch-3 end-points down to 30% ahead and 30% astern.