Catalina II Project

[workshop]

This thread is a continuation of http://www.rcgroups.com/forums/showthread.php?t=631757

For this project, I have abandoned the Telemaster airframe and am in the process of moving most of my gear to the Aero-Master motorized sailplane sold by Hobby Lobby. The Telemaster is a sturdy, capable bush plane and has been converted with a Dragon OSD for short range (<2mile) FPV excursions. Since the wing surface are of both planes are almost the same, I’ll have to reduce my feature set to decrease wing loading.

1. Switch to 5V Video system (read: 500mW VidTX)
2. Eliminate Tilt servo
3. Eliminate redundant RF enclosures
4. Eliminate throttle control (pitot tube, etc.)
5. Smaller, lighter servos
6. Eliminate flaps and flap servos

Ground Station
With help from a flying buddy, I’m going to construct circular polarized long range antennas. In the meantime, I have modified my SUV mounted rotating array with a fiberglass mast and PVC arm. This reduces weight and should help avoid another sprained elbow (a long story :rolleyes: ). I’m using a Yellow Jacket Pro and MaxStream XTend for receivers and have inserted all wires (AV1, AV2, Serial, Power, Rotator) into split flex tube to make things more tidy.

Note: This is NOT my everyday rig. I have found that the best all around video solution is to mount patch antennas onto the roof of the SUV and connect the radio ground to the chassis of the car. I put four eight inch long strips of black industrial (outdoor) Velcro onto the top of the SUV so that I can mount two 8” patch antennas side by side. Luckily, there are four protective strips for luggage that run over the rear length of the roof. I simply continued those lines forward and so far no one has noticed.

Because of a job that will extend into April, construction should progress slowly. In the meantime, I am gaining flight time on three FPV platforms whenever I can. I underestimated the usefulness of this skill (flying FPV with goggles – Headplay in my case) and wish I started with FPV before progressing to autonomous flight. My skills in unexpected attitude recovery, ground based navigation and FPV landing have increased since I started practicing.

Jeff

[mecevans]

looking good!

[icebear]

Nice to see you back here Jeff! :)

I see you have had to make some serious weight watching...

Looking forward to updates and it would be fun to see a specifications of the equipmnet you are putting in. I could work out most of it I think but not everything.

Good luck!

/Bjorn

[_helitron_]

Yeah, nice plane, is comming from Aero-Naut in Germany :) ! Only a little hint, I think it's not a good idea to mount the GPS Rx above the BL-motor :( .

Cheers,

//Erwin

[workshop]

Helitron: My choice is to put the 500mW VidTX or the GPS RX there. I'm not sure which is the lesser of two evils...

JetCruise: I had a really hard time adjusting to the LongEZ. I finally sold it to a guy that really made it shine (he sent video). Take offs and landings were a :censored: but I think it was me... I can fly everything else OK. :rolleyes:

Bob: 4.5" from LE - I may have mine in the air soon to test the Dragon OSD.

So far it looks like I can get the Aero-Master to four pounds on a 4200mAh 3s Lipoly and all the gear. That's 14-15oz./sq.'! :) Photos soon.

Jeff

[Connexxion]

Hi Jeff,

did you see any reason to strengthen the fuselage/wings of the aeronaut?

I remember someone mentioned the need to strengthen the wings for some reason.

I believe it was a italian guy..zaguruinzasky?

[cmoulder]

Jeff, glad to see your new assault on the "crossing"! For electric power, it was going to have to be something very efficient such as your presently-chosen bird.

Thanks for the CG info on the Tele Electro. That is where my CG ended up with no additional ballast and the main (motor) batteries as far forward as possible. When I hang my Fuji P&S camera out there, it will be easily achieved as well.

The conditions were perfect for my maiden flights last Sunday -- except for the snow -- so I fitted some skis in place of the wheels. The flights went well, but I need some down trim in the elevator, and I've got to dial down the pots in the "A" and "T" parts of PicoPilot NAT.

So before you bid a final "adieu" to the Tele Electro, here is a pic of my Jeff P.-inspired bird in the snow. I have a video of the maiden which I will post later. I did not want to start a thread because there's no way I could improve on what you did with this UAS platform.

-- Bob

[workshop]

This IS the best ARC I've ever seen. The fuselage is as close to perfect as one can get; a combination of weight, strength and expert construction. The wings are beyond criticism; light and strong. I don’t believe anything needs to beefed up on this plane with the possible exception of the motor mount. I encircled the back of the mount with carbon fiber; that’s it (I’m using a slight larger AXI 2826 rather than the recommended AXI 2820).

Bob, your Tele on skis looks fantastic. Thanks for the complements.

Jeff

[workshop]

Progress on Catalina II is slower than I like but work should let up soon and I’ll finally have the time I need.

:mad: Danger: :censored:
The rear facing three bladed folding prop sold with this plane has a serious application flaw. If the folding blades are rear facing, there is no fuselage to prevent them from folding beyond the centerline of the prop shaft. It is therefore possible for one blade out of the three to fold into a position that places the mass of the blade over the centerline of the shaft so that it WILL NOT unfold under the centrifugal force of the spinning motor. With two blades deployed and one stuck folded against the spinner, the motor will shake itself out of the plane in a few seconds. :eek: I cannot describe the luck I feel for finding this out before it was too late. I have replaced the folding prop for a fixed one.

Thermal management is tough. The MaxStream gets hot as does the 5.5V regulator running the camera, transmitter, GPS and ODS (1.6A). I moved the hot items forward into the airflow of the nose hole and custom ran wiring harnesses to make things as short as possible. The 6.0V regulator is only running the RX, PicoPilot and four servos so there is no heat worry there.

Full system (R/C, AutoPilot, DataTX, VidTX) bench tests are negative for interference or glitching (that’s a good thing :rolleyes: ). My servos are set for about 70% to 50% of their mechanical throws (as opposed to nearly 100% on the Catalina I) and this seems to eliminate the PicoNAV glitching on manual mode I saw on my last setup.

With an 8oz. battery, I can get the AUW to less than 5lbs. Woo hoo! :cool:

Jeff

[cmoulder]

Bravo, Jeff -- beautiful work, as usual! Can't wait to read about your first test flight.

Have you compared the amp draw of the 3-blade vs a 2-blade e-prop?

Just wondering if you can devise something to keep the folding prop blades from folding too far back. Considerably less drag there. Maybe some little fairings on the trailing edges of the antennas (even behind the video) to give them more of an airfoil shape?

-- Bob

[Gary Mortimer]

Looks great Jeff, could you not have made some wire dipoles and embedded them in the wing rather than the rubber ducks?? I should think they will be pretty draggy.

I look forward to flight reports, I can well see me purchasing one of these when I get back to Scotland in May!

Bring on the next report

G

[workshop]

Maiden Flights
”The Aero-Master is a sailplane like any other sailplane, only more so” (apologies to Claude Raines in Casablanca).

There is nothing much to report here except what I learned about drag. The 900MHz rubber duck was producing enough drag on the right side of the plane to require six clicks of trim to set it straight. I rearranged the antenna to the centerline and reduced the number of trim clicks to two!

I also noted that the VidBatt is suffering about 700mA and that the MaxStream XTend is getting really hot (within spec… but hot nonetheless). I folded some adhesive backed copper foil (RF Shield material) into a finned heat sink and applied it to the XTend. I also cut an exit hole in the canopy to remove some of the air entering the nose. This should help thermal management.

I am moving the OSD to the RCBatt to reduce the load on the VidBatt and send the RC voltage condition to the OSD rather than the VidBatt condition.
ROG: With a four cell lipoly the Aero-Master will rise off grass in about 25 feet. A five hundred foot climb consumes about 100mA.

Change in Flight Plan:
I will now fly from Catalina to San Pedro to take advantage of the usual June onshore flow and increase my landing options. I’ll be able to take a longer climb-out since I’ll be 20 miles from LAX airspace and, by the time I’m near land, I’ll be below the 400 threshold.

I have a week left on my China Olympics project: http://www.flickr.com/photos/24863621@N07/sets/72157604175654880/
Then I’m off to the desert for a few days of UAV! I can’t wait!!! :D

Jeff

[kawika1kalina]

Hello Jeff,

Nice work on the plane, very professional looking. How does she fly?

Did you come up with a solution for the folding prop? I noticed the same and I may have a fix for you, check out post #59 at this link; http://www.rcgroups.com/forums/showthread.php?t=804379&page=4

This set-up worked great on mine and it may help you lessen some drag.

Have you come across any problems with the horizontal stabilizer, like mounting screws or nut coming loss, week glue joint on the center rib of the stab.. ?
I lost the stab.. at about 600 ft. pulling out of a simple stall, it turns out the center rib let go from the rest of the stab due to poor glue joint. You might want to keep an eye on it.

Just thought I'd let you know.

Good luck to you and yours.

Dave

[Gary Mortimer]

I'm going to put a shameless plug in for the thing I have been devoting time to recently.

The excuse being its another method of tracking, using short messaging and the iridium satellite network.

Follow the unit I have hired at http://www.drakensberg.ning.com as some peeps run with it.

I could have started another thread but fear the flames and I'm sure Jeff won't mind.

The transmitter is really quite tiny and GPS as we all know nothing. The battery is what makes the unit quite sizeable.

It will however operate for one year!

Cheers

G

[Airboatflyingshp]

I thought I had posted on this Jeff but I must have got cut off.. would it be poss to relocate the front arial under the canopy? just reduce drag and also to fair in the base of the second with a bit of blue foam or balsa ....just thinking drag and distance.

[spirko]

Jeff,

We eagerly await news of Catalina II. I assume you got busy with work, I myself just returned from a two-month shoot in S. America.

Am wondering if you got the PicoPilot to work well with your new sailplane. I have a 1.8 meter Dreamline sailplane (the Esprit Model equivalent of the Fly-Q or the Omega) and am having trouble using any ailerons for wing leveling on a PicoPilot setup. It works with rudder only, but I’d like it to be more stable.

-Craig

[Airboatflyingshp]

jeff just a bit of interest stuff enjoy...........

http://www.angelfire.com/ks2/janowski/index.html especially page http://www.angelfire.com/ks2/janowski/j5.html :rolleyes: :cool: :D

[Airboatflyingshp]

More inspiration and if its in the way I will take it down mate :)

[cmoulder]

Jeff, any updates?

I finally finished the Telemaster Senior with the G20 and have done a few test flights, although I have not yet integrated PicoPilot nor the A/V payload. Still designing the A/V package, but the basic ideas are already formulated.

Now getting the engine broken in and testing for best prop and exhaust for quiet operation. I have an APC 4-blade 13.8x10 prop and a J'Tec Snuffler At the moment, with a little throttle management I could remain aloft for 2 hours. Main problem now is the stock Zenoah ignition, which is very inefficient and requires a 3850 mah 2s LiPo (reg to 5v) for power. I hope to try a CH ignition in the not too distant future, or perhaps take the advice of Dan (kd7ost) and go to a magneto system. I could easily add auxiliary fuel tanks (in the wings, like real planes) that would keep this bird aloft for 6 hours or more.

[workshop]

I cart wheeled the Catalina II on landing because I didn’t execute the preflight checklist properly. The camera was facing to the left and I didn't realize it when the spotter hand launched the plane. To make a long story short, I am starting over.

Here is the continuation thread:
http://www.rcgroups.com/forums/showthread.php?t=1035810

:o