Telemaster Electro FPV videos

[DiveBombDave]

I just wanted to share how nice and docile this plane is. I'm still tuning it's CG and thrustline, but it was pretty close as designed/indicated.

http://video.google.com/videoplay?docid=-8867812562226252872&hl=en
http://video.google.com/videoplay?docid=-6732632701307949206&hl=en

Touch and goes.... Yes, there are a couple of alarming motor glitches that I found to be a rcvr problem, new one ordered, backup installed now.

Dave

[DiveBombDave]

And a few photos.

[quailbird]

Seems like everyone that has a telemaster really likes them. I've thought a lot about getting one. Nice flying Dave.

[CAFplanekid]

Nice vid! Makes me really, really want to get my ETM up and going. Is your wing 2-piece with that setup? I really like the looks of it, I am not a fan of rubberbands on big planes.

[DiveBombDave]

Quail, CA-

Thanks. It flies so nicely, I did my first real 3 point landing on accident, cross coupling rudder and aileron. Lots of fun!

I decided to make the wing 1 pc after reading about the joiner box construction comments. I, too, hate rubber bands on something this size. I started to get the Graupner Electro Kadett just for that reason alone, glad I went with the slightly larger wing of the TM.

I "borrowed" the technique from Hemperez, I think. One of the "other" TM threads in here. :)

I had to cut a central root rib shape with a "hook" pointing forwards about 1.5" under the LE. I used 1/4 ply for this and the former in the photo above that has the slot to accept the hook. In the rear I added balsa/lite ply build up to accept the wing bolts in the fuse, and I added another small pc of lite ply to add to the one they provide for the wing's rear top, to spread the load of the bolts to the wing.

Soon I plan to epoxy a mating pair of 4 pin connectors to the wing and fuse so the aileron servos automatically mate up and plug in when I drop the wing on top. This'll ease field setup and keep me from swapping the ailerons one day.

Gotta go fly..... :)

Dave

[piglet_74]

Nice Videos. Any chance you can post a pic of your TX setup? It looks like you may be able to help the next time the russians have a problem docking a progress freighter :D

[cars4fun2001]

wich size TM is this?

[DiveBombDave]

hehehe.... The TX is a 200mw BWAV unit that you can see in the first photo. Is that the tx to which you refer?

It is the 6' Telemaster Electro from www.hobby-lobby.com.

Dave

[DiveBombDave]

Today's report -

Added a small amount of aileron differential (down 75%, up 100%).
Programmed landing switch for 40% flaperons, 12% up elevator.
Changed from 13x8E to 13x10E APC prop.

I'm still not sure if I like the 10 pitch prop better, but it does give a smidge more duration if you keep your foot off the pedal. Climb is marginally better, though at a shallower angle. And speaking of duration -

I have two 3s4000mah packs from www.TrueRC.com, and have been breaking them in with 15-20minute flights, recharging with 2000-2800mah. Today I did a flight testing flaperons, so it was higher throttle for a 100' climb and then glide and toss switches/buttons to get the elevator mix right (that's the 12% number). In other words, it wasn't the most efficient use of the battery, and I got in 16.5 minutes with 2120ah out of the battery. This means absolute max time of 31 minutes, realistically I'd expect Low Voltage Cutoff in maybe 28 minutes. So once I get a few more cycles in on the packs I'll try some 25 minute loitering flights and see what we get.

A note on throws:

Just as the book says, 1" up and down on Elev and Aileron, perfect. It's not too sensitive on full rates, but I switch to 60% rates on both when I'm trying to keep the video smooth.

And lastly, a question -

Attempting to fly inverted requires full down elevator, and even then it's slowly nosing towards the ground. Does this mean my CG may be too far forward? It seems to be fine, as far as all other flight characteristics. Any other TM owners fly inverted easily?

Dave

[E.N.]

My guess is possibly CG too far forward but I wouldn't expect a TM to fly inverted very well. A way to tell if the CG is in the right place is to trim the airplane for level flight on moderate power then put it into a power-off dive and neutralize the controls. If the plane pulls up by itself your CG is too far back if it noses over then the CG is too far forward.

[DiveBombDave]

Yeah, that's what I was thinking too. At the time I was trying inverted flight, the "power off nose dive" CG test was yielding a very shallow pull up. Elevator trim at this point is actually a little down, just slightly. This is trimming for level flight with just enough throttle to hold altitude, but when the throttle is closed the plane drops it's nose quite alot. I'm thinking this means it needs more downthrust, so trimming with power on will yield a little more up elevator trim.

I'm going to finalize CG before I shim the motor, though.
Thanks for the input!

Dave

[DiveBombDave]

Well, my glitching problem got worse, but after swapping every part three times (including the radio, crystals, ESC, rcvr, etc). Long story short - the wire I spliced in to make the servo's reach the wing root, plus the 12" extensions on the receiver equal one big freakin' antenna. Removed the extensions and just dealt with cramming my hands in to plug ailerons straight into the receiver, perfect flying today.

I got some Air to Air video with an EasyStar, really close call at 7:03 if you don't want to watch the whole thing. Groundstation battery died before I could land....

http://video.google.com/videoplay?docid=-5770694212978222452&hl=en

[CAFplanekid]

You may have tried this, but twisting the servo leads is supposed to help if you are having glitching problems due to long leads. SOme brands of servos come with twisted leads.

[cars4fun2001]

great vedio as always

[RaptorAP]

Yeah, that was pretty close, looks like you guys were moving about the same speed though!:D

[DiveBombDave]

It took me a little while to remember the flaperons, and then I trimmed it up as far as I could without bobbing. But I had slowed to within a knot or two of his speed. With more practice on both our parts, we may be able to find a higher throttle/trim setting for the ez* that would work well.

I know I'm going to put tilt in on this camera, and that way I have a lot more options for air to air footage. Got some rainy days ahead, be a nice project to celebrate my glitch-freedom.

I was just "hangar flying" some jibber jab with a user in PM's, and I wanted to paste some of the interesting background info on the Telemaster into this thread (with his permission). Larry, aka txflyboys2, wrote:

"I am following your Electro Telemaster post with great interest, as I also have a new ETM waiting to maiden. I am writing in regards to your question about your Tele not wanting to fly inverted well. I am also smiling!
I have flown every version of Telemasters over the last 30 years..........from the original, German produced birds to monsters that were scaled up 50% larger than the "standard" plans. One in particular had a 14 ft. wingspan. The lesson I have learned is that NONE of them ever liked flying on their backs!
When you think about it, it just makes good sense...........the original German Tele was developed to lift and carry "string leads" from one mountain top to another. Those string leads were then tied off to communication lines, which were then stretched and secured between point A and point B. So, the Tele's original purpose in life was to lift (hence the flying tail) and carry these stringers over otherwise rugged and unnegotiable mountain terrain and also be a stable and dependable performer.
The Clark Y airfoil on both wing and tail are going to do one thing as airspeed increases......and that is LIFT and the higher the speed the more it will happen. And regardless of the attitude, it is always trying to "lift" in the direction of the curved side of the wing. So, I would suspect that ANY diving test for trim will nearly always result in at least a slight nose high pitching unless you throw in a TON of down elevator trim or noseweight. After all these years, I find it easier on these birds to just "trim elevator with the throttle".
Tele's are sweet ol' birds indeed and could legitimatly lift a good sized bowling ball. So, I feel they may be the perfect platform for AP.
With a little headwind, I have flown a standard Tele at a negative groundspeed. Our new ETM has flaps and I am hoping that will help it drop into smaller fields and also sit on a dime and offer a good, stable platform for our Canon A620 camera.
With as many of the RCG guys that are now flying these birds, it would be great if we could get together some day and have an ETM fly-in somewhere!"

<<<<<->>>>>>

I'm ashamed I didn't even know it was German originally. :o

And flying a TM inverted is like power-braking Grandma's wagon. :eek: :D
(Come on! I was blowing out the carbon buildup.....)

Alright, gotta run, more videos to come.

Dave

[DiveBombDave]

Alright, another video at the field. However, I mounted a "poor man's heading OSD" onto the nose. $2.99 Ball Compass from the local grocery. Compressing the video doesn't do it justice, but the larger N,E,S,W are clearly visible. For the actual downlink and full res version, once I leveled out it was really easy to see every compass point. Just after takeoff I do a quick nose dive test and flip the compass... at 8:00 I follow two geese onto the pond. At 10:30 I follow a "V" formation and capture them landing on the pond. Landing looked worse than it really was, one 3-4" hop.

http://video.google.com/videoplay?docid=-8975641820682160016&hl=en

Was very happy with how the compass tracked - I thought it would either spin constantly or be illegible.

Dave

[kd7ost]

Hey, thats nice Dave.

The compass looks dark most of the time due to lighting and the auto iris of the camera. Is it easier to see in the raw video? It does have smooth action. Nice job.

Dan

[DiveBombDave]

I'll see if I can post a hig res snip here in the forums for ya, but it was so good I was laughing most of the time flying. The only way it'll come off there is if the TM ever gets a nice OSD like the Inspire.

Dave

[kd7ost]

Cool, :D

Good on ya Dave. I like it.

[DiveBombDave]

Viola - Full res 20 second clip hosted here on the forum. I cut out the geese landing part.

http://www.rcgroups.com/forums/showthread.php?t=598339#post6407000

Dave

[kd7ost]

Looks very fun Dave. Nice piece of work sir. ;) Thanks for sharing.

Dan

[lvspark]

Nice geese landings! I am really suprised at the flight times you are able to get with that plane.. Nice set-up!

[DiveBombDave]

Thanks Dan, Mike!

I can't wait to fly it tomorrow at the field - there should be 3 other guys there with a couple of electrics for some air-to-air practice.

Speaking of durations - tonight I flew two flights, one 16 minute flight at the absolute minimum needed to hold alt - put back in 2001mah. The other was an 18 minute flight at about 4-5 clicks more throttle, tearing around the sky it felt like, and I used 3050mah. I put the handheld GPS in for the slow flight, bringing my AUW to about 108oz, and it flew at 22mph.

I am using the 13x10 prop now, when loitering it gives about 10% more duration sacrificing about 3oz thrust.

Dave

[DiveBombDave]

Couple of new air to air videos -

One hosted locally, high res but short, running down an easystar:
http://www.rcgroups.com/forums/showthread.php?t=602446#post6452750

The other hosted at Google Video, 2.5 minute clip chasing some Parkzone warbirds at a higher throttle setting:
http://video.google.com/videoplay?docid=7245712723124308814&hl=en

I almost blitzkrieg'ed the FW109..... :)

Can't get over how nice this flies (as well as the glow guys at the field). One "Glow guy" even asked me to price my 2m electric warmliner when he saw it doing 15 second climbs at 1800fpm, two dozen on a 2100 pack. Some GPS testing shows I can fly the telemaster as slow as 18mph with 40% flaperons deployed and enough trim to hold the nose pretty high. Chasing the warbirds I averaged 30mph. WOT level yields about 55mph. Most flights have been 20-22 minutes and uses only 2200-2600 mah out of the 4000mah 3s pack.

Dave

[philthyy]

Cool! I've been following this thread closely also because I plan on getting one of these birds next summer for FPV using a new high end digital camera and long duration flights. Your flight times are awesome! I gotta get one of these planes!

[DiveBombDave]

Thanks Phil! You know Hobby-Lobby is having a 20% off any one item until 7:00am, right? :) I have a Sr. TM in my cart right now, hovering on the order button. The mini-TM ARF will be in stock on the 30th, and I want one of those, too! No kidding!

It was surprising how much fun the TM Electro could be while chasing the warbirds. They kept saying, "Can't shake him...." :D And they would comment on how it was staying up longer than any two other planes at the field.

Gotta get some sleep, thanks again.

Dave

[wrenwright]

Here are some videos of the 12' Telemaster that I took at SEFF '06. You can see the 8' and 6' versions flying around too.

http://www.youtube.com/watch?v=_yS1PZGBYf0

http://www.youtube.com/watch?v=BWH2SwaJ5jg

http://www.youtube.com/watch?v=IQ9lxX5PuVA

[Mr.Pibb]

Dave,

I glanced through and didn't see you mention: what motor are you using on this setup? I have been leaning toward this plane for FPV/AV/AP, and now after seeing your videos I'm sold. I was thinking about going with a "budget" motor like this:
https://www.unitedhobbies.com/UNITEDHOBBIES/store/comersus_viewItem.asp?idProduct=2139
I believe I've seen positive reviews about their stuff, but I'm going to look in to it more before I buy.
Anyway, great videos. I hope to have my own FPV's soon.

[DiveBombDave]

Mr. Pibb-

I am using the Axi2826/12 on a 3S1P4000 (truerc.com) with an APC13x10. It draws about 32 amps making about 340 watts. Takeoffs just above half throttle, as well as shallow climbs. My AUW is 103-108oz, I went with a 3.5" rubber wheel (heavy) and converted the wing to a bolt-down system, adding more weight from stock. I used MG85 servos, had to modify every location as they are made for full size servos. The MG85 has plenty of power for it's weight, I use 4 (no flaps). Flaps might be needed if you plan on a very heavy payload, but I'm nowhere near needing them for landing. The video system is very light - Panasonic KX131, BW200mw, 2s700 lipo. Flights with the handheld GPS run up the AUW to 108oz. I'm running a UBEC in case I want to drop a 4S lipo in.

But I haven't needed one yet... It'll climb better on the 13x8 and draw around 30amps on 3S. On 4S, it may draw 32-34 amps on that same prop, and with the extra volts it ends up being almost 500 watts, and that would be the limit of the motor. I use the 13x10E on 3S and takeoffs are maybe 40 feet if WOT, climb is in the 500-700fpm range. The 10 pitch prop sacrifices a tiny bit of thrust but gives me a better duration. It is stalled audibly until about 5-8mph or so of airspeed, during takeoffs. If you want to eek some more climb power out of this motor on 3S, a 14x8E prop would clear fine.

I really trust the Axi motors... but there are several other options out there. Hyperion makes a good motor in the $85 range (www.allerc.com) that they spec for the Hyperion Glass 25e P51 Mustang, and it's the same as the motor I'm using more or less. Any off-brand motor I'd try to get close to the 2826/12 specs, some people use the /10 wind to get more "power" but really they just want more amps on the 12-13" prop; the /12 can make the same power just a larger prop.

Love flying it, ordered a MiniTelemaster, just waiting on HL to get them in. I'm turning it into a real burner with an axi 2808... :)

Dave

[DiveBombDave]

An update on the TM -

Testing a 4S4000 on the same motor with a 13x8E prop. Much more power for steeper climbs. You all know the EasyStar I've been "chasing" in some of the videos? Well, today -

I caught it. :o

http://www.rcgroups.com/forums/showthread.php?t=613749#post6586814

Very short crop, if you've watched no others watch this one.

Dave

[FoamingInMI]

Ouch! Looks like you guys were really up high too. Isn't it amazing that with all of that sky around you managed to run into each other! :eek:

Fun to watch, but not fun to see first hand I'm sure.

Gary D.

[DiveBombDave]

Just wanted to update my 4S experience -

I flew today for 45 minutes on 3420 mah of the 4000-4S pack. Kx131, bwav 600mw, 2S700 lipo. Used 340mah out of the video batt. Perfectly filled a 2gig SD card in the MPVR ground recorder.

I'm ordering another 4S pack, I think it's the only way to go once you add some weight to the TM. I went from 330 watts to about 430, climb rate almost doubled, duration is up 50%..... and it still flies very lightly. It holds altitude with the 4S at about 1/4 throttle.

(edit note- I was wrong! I was drawing 46amps on a fresh 4s pack with the 13x8E! I have since propped back to a 12x8E at about 38 amps)

Oh yeah, one last thing - ordered an Inspire OSD http://www.dpcav.com/inspire/inspire.htm so I will have some more interesting videos. As is, I'm unhappy with the prop in the view and the video tx position in the fuse. So I think I'm moving the cam and tx out on a wing, but the OSD complicates this. Still 'ciphering on it.

Woo-hoo!

Dave