R-Duhb

I pulled my Rich Uravitch 52" OV10-Broncoout of the crawl space with the intent of FINALLY flying it. It's the kit version I built several years ago and it has two O.S. 25FX's in it. Is there anyone out there who has flown this version that can recommend good control surface throws? Also where should I balance it at?

Thanks!

Lnewqban

May be trying to contact this kit manufacturer:

http://www.hobbyhangar.com/newhh2_009.htm

Or PM the members participating in this thread:

http://www.rcuniverse.com/forum/m_97...tm.htm#9741919

Carlos Murphy

My Feedback: (72)

Dual rates, high rate full deflection, low rate half deflection on all surfaces then fly & try.

My ARF Bronco needed much elevator to rotate, I'm guessing due to the trailing arm style landing gear which seams to put the wheels a bit too far back from the CG.

Rather than bend the landing forward I just left er on the runway a little longer before rotation.

My CG was right on the spar, very stable and predictable flyer.

CanDo

R-Duhb, I have the same setup that you have. Unfortunately I'm not where my plane is right now, but I can give you the CG and control throws information in a few hours. I can tell you that with the OS .25FX motors, this plane can cruise at 1/2 throttle and pull lots of vertical at full throttle; it's not marginal power! I also found the main gear was too far aft, which required lots of elevator and speed to lift off. When I later installed retracts, I moved the mains ~1/2" forward which gave me smoother takeoffs.

R-Duhb

CanDo,

I'm breaking in the engines nowand haverun about two tanks thru so far. They sound great, ESPECIALLY when they're running in sync! I bought a mini tac to tweak them as close as possible.

Was it hard to add the retracts? By the way, what kind of retracts did you add and how much weight did it add?

Thanks for the feedback and looking forward to getting the throw information from you.

CanDo

-Sorry for the slow reply, I'm at work. Using your tach, make sure your motors are running 200 to 300 RPM lower than peak RPM (on the rich side). If one motor is running a little higher than the other, it's really not a big deal. If it bugs you, richen up the faster motor a little to lower the RPM.
-I used Spring Air retracts on mine. Because it was a kit, I left a little room and made some mounts. My nose gear is a bulkhead (vertical) mount. Because they were my first retracts, it was a challenge, but it's best to take your time and problem solve your way through it one step at a time. I don't have the numbers in front of me, but I believe the total weight difference for the retracts was ~8oz. Don't worry if your plane weighs ~7lb ready to fly, mine is in the 28 oz/sq ft range and handles wind really well.
Back to work!

CanDo

Here is your information:
-CG: 2 1/2" to 2 3/4" from the leading edge. This is just means it should balance on the spar. Mine is a little nose heavy at 2 1/2", but it works for me.
-Ailerons: +/- 3/8" (High), +/- 5/16" (Low)
-Elevator: +/- 5/16" (High), +/- 1/4" (Low)
-Rudders: +/- 5/8" (High), +/- 7/16" (Low)
With this set up, my plane is very smooth; it's not a 3D machine, but my buddies seem to like it. I don't fly this plane often now, but every time I take it out for a warbird meet, it feels like I just flew it a week ago.

kakariki

My Feedback: (6)

Hi
Do you remember which model of Spring Air retracts they were, a search bought up a lot of different ones, most only for planes up to 3kg which is at the upper limit for weight for the Bronco.
Thanks Barry

CanDo

Hi Barry,
I searched through my old parts boxes and came up with a Spring Air stock #204 HD label, but that number probably goes back at least 10 years. If that number isn't valid, I would search for some current gear that can handle that weight range. I believe Robart sells similar gear now too. I wouldn't be too concerned about the gear automatically lowering when you lose pressure, just pressure check your gear periodically to make sure you don't have any serious leaks. A good system should hold pressure for at least an hour, some will hold pressure for several hours. Also make sure you can cycle the gear up and down at least 3 times before you run out of air pressure. If not, you may want to put a bigger tank in.
-Les-

CanDo

Well, after searching the Spring Air website, http://www.retracts.com/Retrax_100.htm ,
I believe stock #101 is probably the gear I have in my Bronco. The 5/32" gear is plenty strong for this plane (3/16" gear is good for a 15lb plane). The gear that swings 100 degrees is better for the main gear however. My gear is 90 degrees and doesn't quite hide the entire wheel in the nacelle. Keep in mind too that the rudder and elevator cables will have to be routed around the main wheels.

kakariki

My Feedback: (6)

Hi
Thanks for the info, I've just ordered my Bronco, so I'll have a good look when I get it.
Barry

ronwc

My Feedback: (404)

These are very good flying planes - mine is about 10 years old and has two OS 25 FSR - here's a few pics -

smithth

Great looking OV 10. I have one also from Hobby Hangar, I love it but made one mistake which almost cost me the plane. When glueing on the elevator control surface, I thought I had gotten all the hinges well. I was wrong. On the planes 5th flight, the elevator departed the airplane. Im sure you can imagine my heart racing a 100 miles an hour as I tried to control this plane. I was able to keep the airplane in the air for almost 5 minutes trying to learn how to fly all over again. Of course at this time I had no idea that the elevator had departed the aircraft. All I knew was I had a serious flight control problem. I was able to land the plane in some tall grass but it hit pretty hard. Nacelles and wing were fine but he main fuselage had some serious damage. Airplane is currently being repaired and it will fly again. What a great flyer and it looks awesome in the air.

lilhachet

My Feedback: (2)

you wouldn't happen to have the instructions for this kit? Thanks, Guy

smithth

The instructions from Hobby Hangers OV10? Yes I do have them. I can scan and email them to you if you would like.

R-Duhb

Hey Cando,

I know it's been awhile since we chatted about the OV-10. Question..... What did yours weigh in at? Also did you have to add any weight to balance it? Mine is EXTREMELY tail heavy!!! I'm gonna have to add an inordinate amount of weight to nose to get it to balance at the 2.50" - 2.75".

CanDo

After adding 4" to the wing, adding the retracts, etc, mine weighs a hefty 7 lb. Even at that weight, it handles well, especially in the wind. All OV-10s big or small come out tail heavy; it's just a matter of how much. Knowing that before I built my 80" one, I worked on making every part aft of the CG as light as possible, but I still added a couple of ounces of nose weight. On my smaller one, I put my battery pack up near the nose gear, but I didn't have to put lead in the nose. I know a lot of folks have.

R-Duhb

Thanks for the information. I moved the battery upfront as well. Prelim testing indicates I'll need to add about 11 ounces.

Thanks again!

CanDo

You're very welcome. I hope you enjoy your OV-10 Bronco as much as I have mine!
-Les-

R-Duhb

Hey CanDo,
After about 9 ounces added I got it to balance. I put as much in the nose cone as I could fit. The remaining is mounted on the forward gear wall. (Drum roll......) It now weights a HEFTY 8.62 lbs. DAMN!!!
I can't wait to see how she flies.
R-dubh

kakariki

My Feedback: (6)

Hi All
Good to see this thread come alive again. As I mentioned I ordered a Bronco from Hobby Hanger, but unfortunately it didn't arrive and I lost interest. Maybe I'll try again or look for another and hopefully share some info.
BB

CanDo

-Sorry for the slow reply, I wasn't subscribed. R-Duhb, 8 2/3 lb is a hefty wing loading, but not impossible. You will need to carry a little more speed, so go easy on the elevator. The good news is I can fly when others are grounded by the wind. Make sure your motors are happy before you fly!
-Kakariki, I started building mine from plans originally, but in order to save some time, I got the kit. It does take some time to build, but if you keep the tail as light as possible, you will have a very unique plane that looks cool and flies great!

R-Duhb

The 8.62 shocked the hell out of me! I built strickly per the plans and instructions. There isnothing drastic I can point to that accounts for the extra weight. Heavy balsa and ply I guess.
Now I wish I had added the extra bay to the wing. Oh well.......

I've got about three tanks of fuel through each engine so far. They sound great!

Needless to say, I'm gonna be a bit nervous when this one goes up.

R-duhb

CanDo

-I'm sure you did nothing wrong, the weight just sneaks up on you. I replaced lite ply with balsa wherever I could, I selected my lighter balsa for anything aft of the CG, kept the paint to minimum, made sure everything fit well to minimize glue joints, etc. Usually it's just a whole bunch of little things that add weight, not one thing.
-You probably already know this, but double check to verify the motors are a little rich (verify by holding the plane vertical for a few seconds). On take off roll, give it lots of ground speed before you try to lift off. I've found it's best to ease the throttle up, don't just jam the stick to full throttle to start rolling. This will help a sluggish motor accelerate smoothly.
-Note, if your mains are too far aft, it will take a lot of speed and elevator (force) to get the nose up, but when it lifts off, it will suddenly zoom upwards; be ready to reduce your elevator input if this happens. When I installed my retracts, I also moved the main gear forward a little, which greatly reduced the "zoom" at take off. Now it takes off like a "normal" plane!