OV-10 Bronco 81"
 

Anyone build Uravitch's 81" Bronco? Nearly completed and it's coming in about 12 lbs. or so. What engines are you using?

Bronco
 

Hi, I am about to start on mine....I measured the plans and I believe .91 OS FX's will fit if you don't use the wooden block offset on the firewall...THey may protrude out of the top though...just a little....Mr lumpkin aka TWIN MAN says to go large like a .61 and up if you fly off grass besides you can throttle back...I am still debating myself...

color schemes
 

By the way what color scheme are you going with??? Any mods to the plans??? I heard you are probably gonna come out tailheavy.....move that battery to the nose....

Caution
 

ACHTUNG!!! Caution!!!! I remembered that you'd better reinforce the horizontal stab/elevator mounts as 3 seperate people had elevators fly off in flight.... Just a warning..

OV-10 Bronco 81"
 

There is a post nearby that I started several months ago about my Dad's OV-10.

12 lbs is really light. Ours is closer to 20 (for a number of reasons - including a pound of ballast in the nose ) and 2 saito 91's provide plenty of power.

It is a sweet flyer!

OV-10
 

My ears are burning. Yes, if the plane is over twelve pounds and you fly off of grass, I would suggest at least 90's.
Mine at rcwarbirds.com is a little heavier and I wanted scale three blade props, so it has a "Little" larger engines.
Good Luck,

OV-10 Bronco 81"
 

I scratch built a 70 inch version. Mine is about 13lbs I'm not sure always been to scareed to weigh it!! I first flew it off of grass with a pair of MDS.40's It was scarey a little low on power no room for mistakes. I went to a pair of Thunder Tiger .61's and made a fun airplane to fly. I mistake I made was not putting flaps on it, landing speeds are very high. We have about 900 foot of very nice grass runway and it takes most of it to land! Live and learn high wing loaded airplanes need flaps!

OV-10 Bronco 81"
 

I have both nacelles framed up and the fuse framed on mine. I wasnt going to put flaps on, but now I think I will. Still havent chose what retract to use. I've been shopping, found some scale looking retracts, but $$$. But I like em!.....Don't tell anyone, but I ran nyrod thru the fins for the elevators..... Then I read to beef up the stab area...... so I chose to drill a few holes and glue 1/8 inch dowels thru the stab and plywood nacelle sides......Yup you guessed it. Shhhhhh.... I drilled right through the nyrod caseing on both sides. Put a dowel right through em' both...duh
Actually, my repair job made things a little smoother, and I believe stronger.
This is a cool looking plane, I can't wait for the first high speed low pass........

OV-10 Bronco 81"
 

I will not tell you know sometimes things just happen! I have alway felt it usaully was for the better. I think you will like having flaps. I took off work Friday it going to be nice here and hope to get a few more flights on the OV-10. I will try to get a picture to post.

OV-10 Bronco 81"
 

PICTURES PLEASE!!!!!!!!!!!!!!!!!!!!!!!

OV-10 Bronco 81"
 

I've got the smaller version with 2 OS 28's, and I'm contemplating building the larger one...anybody know who's making glass cowls for it ??? What retracts are you guys using ??

OV-10 Bronco 81"
 

I build mine the cheap way, we fly off a grass field I did fixed gear. I also do not have cowling on this one. I had a small one with MDS .28s on it and the overheated with the cowls. The way the fire wall is on the OV-10 you need to duct the hot air out some way, mine did not have enough exit area. I fixed it the easy way on the bigger one I left the cowls off. Yea I know it does not look right but it sure is fun to fly!!!

OV-10 Bronco 81"
 

here is a couple....


http://www.rccanada.ca/albums/album12/abg.sized.jpg

OV-10 Bronco 81"
 

It is modeled after one NASA still uses for atmospheric research.

http://www.rccanada.ca/albums/album12/abh.sized.jpg

OV-10 Bronco 81"
 

Nony, What kind of engines did you use? Do you have trouble keeping them cool?

OV-10 Bronco 81"
 

Thank you so much for the photos, I read the review in the latest issue of MAN, I'm thinking about going with the Thunder Tiger GP61s.I also like the Precision retracts, They offer both fun scale and scale. Check them out at http://sierraprecision.com/prod16.html
Century Jet air had a set for the Bronco as well. I emailed Robart but they havent gotten back to me yet. (It's been two weeks)
These are,I Think, what I'm going to use in mine, I still have to build the wing, So I have time to research and ask around.
Oh Yeah, How did you fasten the stabilizer to the finns? I'm looking for a quick,strong way without having to rebuild (too much) what I already have built.
Thanks!

OV-10 Bronco 81"
 

It is powered by 2 Saito 91's. The engines were moved 2" forward for clearance and it helps with the cg. They run perfectly - no problems at all with cooling.

I will have to get back to you on the stab mounts. It is my Dad's plane, and I will check with him. I know they are strongly reinforced over what the plans recommend.

fiberglass parts
 

They are available but I don't know from whom. I bought these from someone here on RCU. The balsa parts are from the Uravitch plan. The glass parts are less boxy and just look better. Going to use two St 90's. It will have 14 servos and two flight packs (one in each boom.) Elevator servos are mounted in the fins. too much binding and slop using bell cranks. Spring Air retracts.

OV-10 Bronco 81"
 

Hi Drifter,

I would be grateful if you could put a picture of the retracts on this topic as I am thinking of getting the Spring Air units for my Bronco.

Many thanks,

Sarah

retracts
 

The retracts are heavy duty with a firewall mount nosegear. Simple wire struts. The nose gear strut from Springair was unusable because the coil struck the gear frame preventing complete retraction. I had to bend my own. The scale gear from Sierra looks good but is way out of my price range for a sport plane.

I was an OV-10 Driver......
 

I loved flying the OV-10...did a tour in Vietnam as a Forward Air Controller.

Anyway, you guys are doing a great job with your Broncos.

Here is a pic of a full size OV that is at Davis-Monthan AFB in Tucson.

FAC
 

Russ, What squadron did you fly with? Im asking because my father was FAC in 68-69. His call sign was Covey 220, Based at DaNang.
Evan Quiros
http://www.homestead.com/evoshangar/home.html
Looks like Im gonna have to add a bronco to my warbird collection. Drifter, Id like to know who makes those fiberglass parts.

parts
 

I purchased them here from this ad:
http://www.rcuniverse.com/showthread...t=bronco+combo]

OV-10 Bronco 81"
 

I am about to make a new building board to build a number of models on. Could someone please let me know what size of board will be required to build the Bronco on, as I am waiting for the plans to arrive.

Many thanks,

Sarah

building board
 

Sarah, I built one (the 81") on a 24"x48" board.
Lots of luck.

OV-10 Bronco 81"
 

Good Lord! I already have more planes than I can keep operating/ build/ stay current on/ afford, but I really want one of these :greedy: Especially the fiberglass parts. Sheesh.

I gotta win the lottery and retire to the shop.

BTW - I found the web site for Bob Sealy, Quality Fiberglass. No mention of the OV-10, but definitely may be worth a call or e-mail.

http://www.ucrcs.com/quality.htm

BTW- The guy shows what looks to be a really nice C-130 glass kit that goes for $350, shipped

http://www.ucrcs.com/10222000_C_130_Plug.jpg

OV-10 Bronco 81"
 

Thanks for the information about the board size Drifter, I have seen a building board which is 48" by 18" will that be large enough?

Also thanks for the picture picture of the retracts, Drifter.


Regards,

Sarah

bronco wing
 

The Bronco wing panel is 15" cord by 40.5" span. A 48"x18" board will work. The two wing panels are then joined on something long enough to maintain accurate alignment. The nacelle is about 38" long.

OV-10 Bronco 81"
 

Hi Drifter,

Many thanks for your help.


Sarah

OV-10 Bronco 81"
 

Hey Drifter Man, did the spring air retracts come with all the goodies? You know.....valve, fittings,tubing?

Bronco cockpit kit!
 

Hey guys, if you're looking to scale up the cockpit, then Dynamic Balsa will be releasing their cockpit kit for the Bronco. I don't know exactly when, but they tell me that it'll be around $100.

Dean

http://www.dbalsa.com/index.html

OV-10 Bronco 81"
 

Hey Guys,
I have the RU plans but have not started yet. I did scratch one from three views that I got from North American in 1974.
60" span, two OS 40s, 11.5 pounds.
Articulated gear as per full scale and electric retracts,and flaps.
BTW there is a LONG NOSED version and the nose gear retracts forward to be scale.
Good Luck

OV-10 Bronco 81"
 

Great! I'm glad to hear some one is coming out with a cockpit kit. I searched a quite a few web sites on the OV-10 and could find any useful pictures of the cockpit area. A few side views, but nothing I could really use to build my own. Howz everyones progress on their Bronco?

OV-10 Bronco
 

Just finished covering...decided to go patrotic..corsair blue with red and white. Weather here lousy right now,waiting for nice, warm, calm, spring day for that first flight. Using two OS-61fx for power. I'll try to send a photo in the near future.

progress
 

Getting ready to glass the wing.

Elevator question?
 

Hey guys, did you use 2 servos (and 2 linkages in the booms) to operate the elevator, or just one? Also, how many receivers did you use? I'm thinking of putting one in the wing, and one in cockpit. I will only remove the centre cockpit for travel and storage.

Thanks, Dean.

OV-10 Bronco 81"
 

Two servos,(and pushrods) definately. Even though one might do the job, two will help eliminate flutter. I'm even gonna go for more powerful servos, maybe 70+oz torque for all flight controls. I plan on using one RX with a 6v 1100+maH batt. I found scale and semi-scale retracts at Precision and Century jet but they're not cheap. Robart couldn't be bothered to answer my email whether or not they had something I could use.
Right now I have all componants framed and mostly sheeted. I'm now waiting for epoxy to cure on a few strenghtening modifications I made on the wing, then I can finish sheeting.
Very soon I will have to order the plastics, and choose what retracts I want to use ($$$)
Thanks for the photos and sharing your input and Ideas. Lets have a Bronco flyinn! (If spring ever comes)

Elevator control
 

I've got two Hitec (s-77's I think) low profile servos mounted in the upper fins. I didn't trust the four bellcrank system suggested on the plans. Too much opportunity for slop and binding.

The Fiberglass fins are wider than the same fins done in balsa and allow servo mounting.

I'm using two receivers, each driving seven servos. Each has a 1100 mah battery pack.

OV-10 Bronco 81"
 

Where can I order Uravitchs plans and stuff,I know Ive seen his ads and a review or something I just cant remember which mag ..SteveD

Plans
 

Go here for plans:

http://www.rcstore.com/rs/general/de...201a&catego=PL