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YF-19 and SV-51 for radio control


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well, with the gerwalk mode, all the thrust vectors are pointed down while the legs are swept foward. perhaps you could rig a control for the legs?

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Therein lies the problem. The only (major) reason to have a gerwalk mode is to do vertical landings. (Oh, and to stop in midair... But that's another story.)

Anyway, if I want to land on the thrust-vector vanes, I need them splayed... If I splay them, they don't work to vector thrust anymore, so... :( Also, the more I vector the thrust, the greater the losses are, which wouldn't be good, if I were to do VTOL.

~Luke

P.S. In re: a VF-0S... I suppose I could always drop a Ghost booster on top, to get the wing area up. It actually works out perfectly, so configured. :D

Edited by IAD
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A VF-0D... One day, maybe. After Sean's SV, I've got a couple more projects in the queue. Specifically, a 42" span Beechcraft Starship, and a 5 oz. AUW fiberglass motoglider. (Designed to hit 80+MPH, with the right motor.) So, one day, in the somewhat distant future.

~Luke

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Too much power? No such thing. The structure can take pretty much whatever I can throw at it.

~Luke

Edit: Sorry if that sounded somewhat brusque... I was in a bit of a hurry when I posted. :unsure:

Edited by IAD
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OMG!!! You actually comtemplated to make Gerwalk mode works!!!! You are a freak, an impressive freak...you should start a production line on these little numbers and you'll soon have enough money to built a real one... :o

BTY, is easy to become a Defence Minister in Australia...just spent 6 million dollars with taxplayers' money on a bombed submarine that leaks and too noisy to operate...fly your resume in with your SV-51..he..he.. that should impress the voters here :D

The SV just looked too neat in gerwalk.  However, I ran some really quick thrust vector figures, and from a flying standpoint, it looks bad... 

397880[/snapback]

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Heheh..!

Quick question:

Does anybody here know where the section of fuselage/lifting body between the nacelles goes, when the SV goes into gerwalk mode?

Is it part of the gunpod?

~Luke

Edit: Just did some frame-by-frame... It IS part of the gunpod. I learn something new every day. :rolleyes:

Edited by IAD
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Well... I just got a thrust-test in, using the old 5300 k/V motors with the [new] 1320 mAH Pro-Lites. (Half of the planned upgrade.)

Just changing the batteries, I got a 1.5 oz. increase in thrust! I also lost 0.3 oz., thanks to the new battery. So, thrust went from 5.15 oz. up to 6.65 oz., and the weight went from 12.95 oz. to 12.65 oz.! (And that's without the new motors installed yet!)

Better than a 1:2 thrust-weight ratio, finally! :D

Of course, the 0.3 oz. weight-loss is negated when I install the new motors, since I suppose I'll need heatsinks. But as long as I gain at least 1 oz. of thrust, the T-W ratio will still be considerably better. Plus, the top speed should increase, which is good for energy-maneuvers.

~Luke

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Oh, FWIW...

This configuration has workable wing area... :D:rolleyes:

Ok, now off to set the workshop straight, and dust off the SV thrust-vector paddle cutting templates.

~Luke

(Yes... The VF-0S has the wrong canopy... It's left over from the VF-0D cutting templates I had worked out.)

(Well, not any more. Fixed it.)

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Edited by IAD
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I gotta say, that SV-51 is purely amazing... and Gerwalk? Never would have thought it possible on an RC, but if you're willing to try then more power to you (literally, it would seem).

Just had one other thing to say... dunno if it had been mentioned (I know it wasn't on the RC forum), but you were asking about the swept wing on the YF-19 a while back. In the games Macross Plus and Macross VF-X2 (both for PSX), the YF-19 flies normally with the wings swept forward... but if you hit the thrust button, the wings sweep back to a more "VF-1"-esque position. Double-tapping thrust activates a rather energy-draining full burn, in which the wings sweep fully backward.

I guess I can provide some screenshots from in-game. Quality's to be expected from a PlayStation game.

http://img467.imageshack.us/img467/8868/swept4cp.jpg

http://img55.imageshack.us/img55/1817/swept21by.jpg

http://img55.imageshack.us/img55/651/sweptfull8mu.jpg

It should be noted that when the wings are in the partially-swept configuration, the tail fins come inward about 70-degrees (bent inward as far as they were bent outward before), and when in the fully swept configuration, the tail fins flatten inward against the engine nacelles.

Good luck with all of your RC projects, the look amazing thusfar. ^-^

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Very interesting... I was aware of the 'oversweep' position, but I never heard of an intermediate sweep.

Of course, are those games considered 'official' references? (Just curious, I'm not too picky, but others might say it's cheating... ;))

~Luke

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Next is a relative.... Like I said, after Sean's SV, a couple of aircraft that need upgrading/modification, maybe an own-design or two... ;)

But yes, probably. A VF-0S + Ghost is likely in the future. (The QF-2200 is just for wing area, so that the VF-0 can be built to the same scale as the SV-51. It wouldn't/won't have another motor/fan.)

~Luke

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Actually it would be cool to put a 3rd motor in the ghost to act as a true booster. Just have it hooked up to a seperate switch to activate when thrown. that would be sick to have a RC acft capable of doing a vertical max climb like the F-15.

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Thanks!

I'd love to put an extra motor/fan in the booster... But, two problems:

First, the ducting would be rather nightmarish... A serpentine duct would probably be required.

Second is the battery requirements vs. weight vs. thrust-weight ratio. While the total thrust available would go up, the thrust-weight ratio would not necessarily improve that much... Assuming the fan produces ~5 oz. of thrust, but weighs 1.5 oz., with controller, and requires a 1-2 oz. battery pack, the actual gain in net thrust is relatively small, for a relatively large increase in weight, which is always bad. On the other hand, running a third fan off the standard battery would increase the load, and cause all the fans to give lower thrust...

Working at a completely different scale, with different motors and fans, much better than 1:1 thrust/weight could be achieved... Case in point:

http://www.rcgroups.com/forums/showpost.ph...7&postcount=129

(Not one of my ships, but a good demonstration of vertical performance from a ducted fan.)

However, flight time suffers, generally speaking.

Alternatively, putting a pusher propeller (instead of a ducted fan) on the Ghost would drastically increase thrust, probably far beyond 1:1, and do so using a smaller battery. This would definitely be an option. With a grey propeller, it would be nearly invisible in flight. :D

~Luke

Edited by IAD
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Warning: Theoretical rambling commencing in 3... 2... 1...

The above got me thinking, so I ran some numbers for the SV, with propeller-equipped over-wing boosters:

With a 7" prop., I could produce 12-13 oz. of thrust per booster. Each booster would weigh 3.75 oz., with it's own battery, receiver, motor and controller. Thus, the total weight of the aircraft with boosters would be 20.5 oz., with 32 oz. of thrust, with boosters 'lit'.

However, there's a catch: The high weight of the aircraft with boosters would prevent it from flying well (if at all) with only the ducted fans running. Now we're into jettisonable boosters, which would mean release clips, parachutes, and what-not, plus potential CG variations... :blink:

I still think it would work just fine on the VF-0, which would have only one additional motor/battery... Maybe even leave the ducted fans off altogether, and just make it a pusher prop. job. (Which is probably what I should have done for the SV in the first place. :rolleyes: )

~Luke

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NO NO ducted fans are THE way to go in the SV-51. They may be troublesome to figure out and get working properly but once they are installed correctly nothing looks better in the size.

Of course Luke you could always get into doing 1/6 scale fiberglass airframes with real jet motors. That would be sick. Someone out here has a F-22 with VT on it but just like the SV its hooked in to the other control surfaces. TV needs to be independant to get the kind of reactions made by real aircraft that have it.

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Heheh... Yes, I saw somebody who made a little 3" dia. turbine, which weighed 6.5 oz, and put out a pound of thrust, or something. I couldn't help but think that a pair of those in a larger SV would be rather incredible. :D

You're right that the fans look best, but I will admit being tempted at various stages of development to drop a propeller on the back... 24+ oz. of thrust, on a 10 oz. SV would make for some serious vertical performance.

I agree that the TV ideally should be driven off seperate servos... But you'd almost need a fly-by-wire flight computer to actually use it... How would you control both aerodynamic pitch controls and thrust angle at the same time? (Of course, even with independent TV, a model typically doesn't have enough mass to pull a cobra correctly. They tend to decelerate too quickly, which spoils the effect.)

~Luke

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Ok, it's been a while since I posted build pictures, so.......

Here are a few. Slowly but surely, I'm remembering how to carve SV parts.

I'm almost ashamed to post pictures with mine in there, though... The half-finished paintjob is really damaging to the eyeballs of the viewer. :blink:

Got to finish the second ship, so I can paint mine. (Motivation! :D)

~Luke

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Ok, finally got a bit of work in... (I've been unexpectedly tired, the past couple days. :unsure: )

Anyway, here are the almost-finished thrust-vector vanes, for the second airframe. They look simple, but carving the same exact thing 2-4x is anything but simple. (Oh, but for some experience in fiberglass moulding. :rolleyes: )

Now to install the pivot points.

~Luke

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Well... Progress!

By changing the hinge geometry, I managed to get a few more degrees of upward thrust-vector deflection... Not only that, but the overall effectiveness should be higher, due to a smaller gap between the lower paddles, in full-up position.

Also, I've changed the design a bit, for painting/maintenance sake... On my ship, you have to use a pair of forceps to carefully pull the pivot pins, if you need to remove the paddles. Then you have to twist them around just so, to disengage the paddle interlinks. (In short, a royal pain.)

On this one, you simply remove two nylon bolts, loosen a pushrod retaining screw and the entire thrust-vector subassembly slips right out of the aircraft. Needless to say, it's a lot easier to pull pins and what-not, when the thing is outside the nacelle 'glove'.

~Luke

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Edited by IAD
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I've started gluing the airframe together, specifically the lower halves of the nacelles, and the gunpod mount/aft lifting body. This allows me to modify the ducting so it matches the Ivanov airframe. Nasty business... If only I had gotten the ducting right in the first place. :rolleyes:

Anyhow, no pictures yet, but a few somewhat-topical screenshots that might be interesting... With some (very slight, probably imperceptible) tweaking, I managed to get enough wing area on the VF-0S, without the Ghost. :D (And it's still 1/24th scale, like the SV!)

~Luke

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