kenstogie

Thanks ggunners for the FMS model! Maybe it'll help me keep this bird in one piece ;-)

keithn4

hey guys,

im thinkink of buyin the t-28 in the next week or so. been reding this tread for a couple of weeks, sounds like a nice bird. i also have a supercub and want to get this to train me to use a 4ch plane.

ive a couple of quiestions,

im gona change the esc 1st just wondering ha anybody heard of these esc's and are they any gud?

Duremax 25 Amp Brushless

http://www.modelmaniacsonline.co.uk/...5337&CatID=303

TowerPro W30A Brushless Speed Controller

http://www.islandmodels.ie/component...art/Itemid,27/

TURNIGY Plush 25amp Speed Controller

http://www.islandmodels.ie/component...art/Itemid,27/


has anyone any ideas, i really new to electrics,

are any of them any good?
which would ya reccomend and why?
would ya reccomend any of them?

plus do i need to get any thing else for this set-up?

thanks guys for any info,

keith

casey_lamm

will have to check but its whatever it was setup as by the factory.

Tabair

To get a greater roll rate, you have to increase the throws, to do that you need to either increase the throw distance of the servo arm which is probable already at it greatest point, or increase the throw of the aileron control horn. You do this by moving it closer to the aileron. With the rod connected to a hole closer in you get move movement in the aileron for a given movement of the servo. Hope that makes sense. Heres a photo to help.

casey_lamm

makes sense, I will make that change tomorrow at the field. full day of flying for me.

casey_lamm

completely maxed out it would be the inner hole on the sero and the hole closest to the control surface on the wing?

Tabair

Yes to the closest to the control surface on the wing, but it would be the outer hole on the servo ( gives you the greatest movement. For example in the outer hole you might have 3/4 inch movement, while in the inner hole it might only be a 1/4 inch of movement.

casey_lamm

Cool thanks

tubamike78

just got back from the toledo show. lots of great new stuff comming out this summer. they had the e-flite t-34 mentor pts there with a video of it flying. looks like it will be a good flyer. i no sooner got out to my truck to leave when my cell phone rings, someone from one of the booths i sighned up for a drawing, my name was drawn for the aerofly pro delux flight sim. has anyone have any experience with this sim? i've currently have realflight g3.5. i guss i'll install it tomorrow, i should be able to use my 3.5 controler with it and i think i'll pass it along to my 9 year old nephew with the aerofly controler for him to learn on. he's currently flying the sky fly by him self and the super cup with my help.

thelocksmith

Allright I have a battery question, I love this plane but I only get 1 day off a week so I want to fly as much as I can when I can. I tried emailing horizon with no luck about this so I will ask here.

Will A123 batteries work with the T-28? Im looking at getting the 6.6V 2300 Li-Ion packs, they are lower V but higher mah and C will it work? is it to much or to little power? they also make a 9.9V version. Here is a link to the exact battery I want to get http://www.horizonhobby.com/Products...odID=AQR400062

If those dont work is their any other batteries you recommend Im trying to maximaze my cost/flying time.
Any help would be great
Thanks
J.R.

zestril5

thelocksmith

I'm not sure why you would want to be looking at a123 batteries but whatever the reason the 6.6v ones won't work and the 9.9V would give really bad performance if it did work. The Trojan needs 11 volts at a min.
The higher MAH value has very little to do with performance but is better looked at as the batteries "gas tank" the biggher the MAH the bigger the "gas tank" therefore, the longer the plane will fly on a single charge, all else being equal. The battery you linked to is 2300 MAH
The C rating is fairly well fixed for the prop you are using. Change props, or motors, and the C rating can change. The A123 battery you link to is way overkill on the C rating needed for the Trojan. 20C is more than enough.
Check out this link http://www.hobby-lobby.com/polyquest.htm and compare the 2150MAH 3 cell Lipo. It has a 25C rate at 2150 mah and 11.1 volts. Perfect!! Price is quite a bit less than an A123 battery rated at 11 volts.
You can also buy 2100 - 2200 mah 20C 11.1 volt batteries at Hobby city for around $25.00 (that price includes freight) It just takes a little longer to get the order since they are in Hong Kong or somewhere.

Stick with the lipo. A123 batteries offer advantages over lipo but are just not cost effective or everyone would be using them.

JDMjdawg

I see, well I seemed to have found the problem. It turns out that the axles on the T-28 landing gear have too small of a diameter for the Du-Bro wheels causing the wheels to spin inconsistently. When I had originally built my Slow Stick, I used some 5/32" brass tubing to make a new dihedral brace. This tubing has the perfect outside diameter for the Du-Bro wheels. I cut sections about as long as the wheel hubs and then glued them to the T-28 axles, then I mounted the wheels on the T-28. Now the wheels spin like they have bearings! I guess my problems with taking off and what not before were due to the wheels turning very poorly on the axles prior to the brass tubing mod.
I sure love these wheels now, I have no complaints whatsoever

thelocksmith

Thanks for the info im new to all of this stuff..

So not saying this is what is best but if I under stand right I can get a 5000mAh 3S1P 20-30C and it should not be any better or worse performance then what I get now just alot longer flight times. And is their any of thease at hobbycity I should stay away from? or any 3S1P 20C is ok? and Do I need to buy a new charger or will the charger that came with the T-28 work?
Thanks for all the help
-J.R.



"Now I just need to find a new wing nut, got to the field ready to fly and relized the nut that holds my wing in place was gone "

tony51

Saturday, April 5, initial T-28 flight results ...

All batteries were freshly charged, electrical connections all were checked, a range check was done and all controls appeared to function correctly. And of course a check was made to assure that no other rc gear using the same frequency was active. Wind is steady at about 10 mph, without gusting. In the air, the plane at first seemed to be very well-behaved, responding to transmitter signals exactly as it should. However, during the brief flight (2 minutes max) there were several instances in which the plane very suddenly banked left sharply (about 45 to 55 degrees) and then almost instantly returned to level. The entire incident in each case occurred within at most half a second, and was not due to any manual (pilot) transmitter control movement or wind gust. After that happened several times, the plane was landed so that no additional problems might result in a crash. No other kind of control problem was observed during the flight.

After landing, all reachable electrical connections were rechecked and all still were OK. We again verified that no one else at our club field was using the same frequency, just as we had before the flight.

I called Horizon Hobby (Parkzone) tech support today, and after a discussion the support person said that I should return the entire plane for repair service. Because the cost to return the complete plane is not low, and because it seems relatively unlikely that the problem is with servos, we finally agreed that I would send in the tx and rx only. (I have the alternative to drop in my new Futaba 2.4ghz spread spectrum gear, but I paid for a good tx/rx with the T-28 and that's what I want HH Parkzone to provide.)

One additional possibility is that the problem at least in part might be with the ESC. I have read that some people have had esc problems with their T-28's, but if the esc were the failure point then I’d expect other control problems, not just aileron. However, maybe other problems would have appeared if I had flown the plane longer.

Since the product is recently purchased (March 15) I am expecting the transmitter and/or receiver (or esc?) to be repaired or replaced at no further cost to me other than perhaps return shipping.

On the good side, when the T-28 was flying as it should, I was very well impressed with it. Regardless of this "out of the box" problem, I expect the T-28 to be a good rc plane.

zestril5

thelocksmith

Your understanding is correct. One caution though. a 5000MAH battery costs over $100 more than a 2100 or 2200 MAH battery. You wil NOT double your flight times. In my opinion anyway, the most cost effective is the 2100 or 2200 mah battery for may applications. Perhaps others have $.02 to contribute regarding this arbitrary number but it's the most common battery recommended by most contributers posting in this and the supercub forum.

I can't speak for all the batteries at Hobby CIty but I have purchase and distributed to 5 other flyers both zippy and ABF batteries. We are all happy with them.

Now for some bad news. I doubt that the charger that came with the T-28 will properly charge the batteries we're talking about. It might, I don't really know. BUT......if you intend to stay in the hobby don't go cheap on a battery charger. All else is fleeting and destroyable with the wrong turn of a dial. But a battery charger is a Necessity and as you continue into the hobby you will acquire different types and sizes of batteries. You want a charger that will handle all of these not just one. You also want a charger that can charge both at the field and at home. You also want a charger that can charge quickly and charge more than 1 battery at a time.

Check Tower hobby for their Superbrain 977 or Hobico.com for the Accu-cycle elite. Both are great chargers. Neither is cheap. But I look at the charging of batteries to be the heart of the whole flying operation. Cheap wouldn't really be prudent.

zestril5

Tony21

Don't be so quick to dismiss the servo as the problem. My Aileron servos made noise ever sine I first got the plane in November. Didn't see any problem, however, except a little noise so I have been flying it since Nov with stock Esc, Motor, and servos.

Had a crash the other day due to a turn I couldn't control. I though it might be an aileron servo but they worked well testing them back on the field bench. Finally decided to take off again and just befor take off......POOF no right aileron. It had gone completely bad that quick. I believe it had been intermittenly bad for a long time

This was my experience for what it's worth anyway.

thelocksmith

ty for your help, I will probably put an order in some time this week for some 2200's and then order a nice charger. You made a great point since I really am in no hurry to go to glow or gas powered that a good charger is a must, I purchased a nice radio system cause I felt it also is a must.
Thanks
J.R.


P.S. Is it just me or the deaper you get in this hobby the deaper you have to reach in your pocket? But man I LOVE flying!!!

tubamike78

while you are waiting for the radio to come back, you could always put in your 2.4 and fly it. this will tell you for sure if it is servor or not, but most likely it is radio.

BoysToys

I installed my ParkBEC yesterday and then proceeded to fly 4 packs through my otherwise stock Trojan. Everything performed flawlessly.

The only thing I had to be bummed about is that I am still being forced to use the stock radio. I am waiting for the AR6100 that I ordered from my LHS so I can use my DX7. This was the first time I have flow it since I moved the control rods to the second hole from the aileron. The plane did roll a little faster but still not as fast as I would like. I am going to move into the closest hole before my next flight as see if there is any noticeable difference. I was able to do some immalman turns, a bunch of snap rolls, barrel rolls, a few split S's, some sad looking cuban 8's, and some inverted circuits. All is all it was a great night out flying. I really like how relaxing the Trojan is compared to my helicopters. I am not shaking when I land the Trojan like I am after flying my T-Rex 500.

On a side note, I flew my 2 new Loong Max 3s 20c 2250 packs from HobbyCity for the first time tonight. I flew each pack about 12 minutes using approximately 3/4 trottle the entire time. They flew great and provided plenty of power. They were barely warm when I pulled them out of the plane. They each took around 1900mah tp recharge. That is a more than I would like to take out so I will set my timer for 10min next time I fly them.

Until next time, have some fun and go fly!

MAX HEADSPEED

I had sent an e-mail to HH last week stating that my replacement T28, the 5th and hopefully final unit in a series of attempts to acquire one that would function properly or didn't have an improperly formed main wing or a bent motor shaft or wasn't busted up junk in the box, had been manufactured with two(2) dsvs instead of one(1) thereby border-lining or over-loading the the ESC IAW the chart for the ESC spec sheet. I asked them if this was a mistake and if the servo should be changed out or should I 'JUST FLY IT' like it says on the box? The parts listing shows only one DSV being used on the rudder/nose wheel steering and the other three being micro servos but not digital. This issue was addressed earlier in this thread but was never resolved or discussed since.
So both servos in the fuse, rudder/steering and elevator are digital and the servos in the main wings are not digital. I told them of my concerns about having an issue with this B1-RD and that I would wait for their reply concerning this matter prior to giving it up to the air and gravity gods.
I haven't heard a peep from them in a week. Seven days! Maybe they lost my E-mail. Maybe it's just a simple little communist left wing conspiracy. I'll let you all know what they have to say about this matter if and when they respond. They've always been great help in the past. I hope they don't drop the ball now.
I don't want it to fail like it did during its January 7th 2008 5 minute maiden flight which was awesome until a control glitch took her out of the sky on its downwind turn to base for final on landing. A perfect low level left snap-roll from a right banking turn....wow! That was one long and memorable retrieval hike/stroll across a goose **** and mud covered field. My friend's T28 was glitch'in badly but he was able to land it. The whole kit was replaced by his LHS.

KEEP'EM FLY'IN!

BeavenX5

I have A123 batteries in my e-converted buggy and they are great batteries. Each cell is 3.3v compared to 3.7v for lipo so you have to consider this seriously when going from lipo to A123.
The main advantage of A123 over lipos are:
1- safety: they are much more stable and won't catch fire if mishandled. Lipos are safe only if treated properly...
2- durability: A123 batteries can take lots of abuse (excess amps draws, over discharge, dropped on the floor) what lipo won't tolarate. A123 batteries are also supposed to last over 1000 charge. 4-5 time more than lipos
3- greater "C" rating. A123 are rated at 30C wich means you can draw 70amps from them compares to up to 45amps with a 20C 2200mAh lipo.
4- fast charge: Because of their "roughness", A123 batteries can be charged safely at 4C wich is only 15 minutes compared to 1 hour for lipo. You only need 2 batteries to fly all day long...
5- longer flights: you can discharge safely A123 batteries more deaply (down to 2v per cell) than lipos therefore, for the same capacity, you can draw more "juice" out of them.

As Zestril mentionned, you don't need 30C or more capacity (mAh) with the Trojan. The main advantage on your T-28 would be safety, durability and fast charge. They will also be usefull if you get larger plane in the future.

As an exemple, I just finished building a Richmodel 3.25pounds P-38, both motors together draw a peak power of 36amps: too much for my lipo batteries: 15C 2100mAh = max 31.5amps. I am currently flying it with two lipos in parallel to make up for the 36amps draw and the performance are a bit underpower. I just ordered a new Dewalt battery to make myself two 4s A123 batteries for this P-38. At 13.2v instead of 11.1v, the performance will be greater and being able to draw 70amps on one battery, I won't need to put two of them in parallel and therefore will save some weight. I think this is an exemple where A123 batteries have a significant advantage over lipo...

Thelocksmith: if you still want to go with A123 batteries on your T-28, you will need to go with 4s: 13.2volts. I fear that 9.9v might be too low voltage and performance will suffer. You will have to check if the motor/esc is able to handle 13.2v... probably yes... Unfortunately you won't find 4s A123 batteries on the market: you have to buid them yourself using Dewalt 36v battery pack. You will see, it is easy, requires minimal soldering skills and is significanly cheaper than the ready to use ones.

For more details on A123 batteries and how to build them out of Dewalt packs click here: [link=http://www.slkelectronics.com/DeWalt/index.htm]A123 batteries bible[/link]

BeavenX5

Keith:
why do you want to change the ESC? The one in the T-28 is perfectly good. The problem with it is the fact that the 2 digital servos used by PZ for the elevator and the rudder draws more power that the build in BEC circuit in the ESC can handle. By the way, BEC means battery eliminator circuit and is the circuit supplying current to the receiver to operate the servos in the plane.
If you fear of burning the ESC in the T-28, you can just install an external BEC to the receiver and unplug the red wire from the 3wires plug going fom the ESC to the receiver. Another option is to replace one of the digital servo with an analogue one that will draw less current from the build in BEC. Both these solutions will keep the E-flite ESC happy and are cheaper than replacing the ESC.


Edit: If you still want to change the ESC, I have both the towerPro 25A and the Turnigy. They are OK but not better than the E-flite. You can get them cheaper there: [link=http://www.hobbycity.com/hobbycity/store/uh_listCategoriesAndProducts.asp?catname=All+Speed +Controllers&idCategory=61&ParentCat=182]Hobbycity in HK[/link]

MonSooN WeBber

Hey Guys,

I finally got my Trojan going. Turns out I had a faulty transmitter out of the box. I maidened it tonight. It is a such a smooth flyer, and very quiet. I am really going to enjoy flying this. I am a newby and am loving this hobby, my wife and my wallet arn't though :P.

I have moved up from a super cub and the transition seemed pretty reasonable.

Monsoon

king_arthur1953

I have been looking at this plane with great interest. I was a crew chief on a T-28D Nomad in SE Asia in 1974-1975. It was much more than a trainer. We had missle launchers and bomb racks with 30 cal guns. We flew ground support missions in the jungle. The flight envelope of the Nomad made it a perfect match for close ground support. (My life was saved more than once by the Nomads sending the KR rebels back into the trees.) I have never flown electrics so this may be my 1st experience into that side of RC airplanes.

Check out this link [link=http://en.wikipedia.org/wiki/T-28_Trojan]T-28D Nomad[/link] The last pic is a decommissioned version of one of theNomads I supported.

zzz12

Hello Beavenx5 have you got some more video clips of you T-28 Flying. What planes do you have in your hanger now ?