1947 Box Car Chief

I noticed about 2:09 the engine is still breaking back and forth but at 2:15 he pulls into a vertical maneuver the engine is starting to sag. The engine remains in a fast 2 until the engine quits. I also just realized to my stupidity the plane was already flying when the video was shot so no telling how long the plane was in the air. So it's obviously running low on fuel and it just shut off. I have to ask how much time is on this Fox? A new Fox can certainly display a behavior as seen in this video in regards to the time it starts due to the engine becoming overheated. That doesn't seem to be the situation here. A Fox is fickle at times and certain issues can be a result of over propping, muffler too tight,  new engine, tight engine, not enough engine for a certain size airframe,  too tight of a liner fit within the case itself or restricted exhaust configuration.   I can't see from the pictures or tell by the sound but is a muffler being used? The flight itself was quite short and during the flight it was continuously leaning from the 2 minute mark. From what I witnessed here the engine just ran lean and shut off. So I would have to ask, how large of a fuel tank is being used? And if it did say have at least a 3.5 oz capacity was there fuel left in the tank?  Seeing this is a OTS plane, I can only assume it has a very small tank. This was  the norm due to the OTS pattern not requiring a lot of fuel. A Fox .35 doesn't require 3.5 oz's of fuel to do a OTS pattern. The head pressure within the tank was certainly lessening therefore the engine was going overlean. I'm also intrigued by the fact the engine was breaking back and forth the way it was. A Fox .35 in a upright or inverted position typically doesn't do that when mounted in this fashion. Certainly not a problem of course, just a design factor of the engine. I would be very satisfied with that run with the exception of it going lean to the point of overlean  throughout the flight. Essentially muffler pressure could assist the run into higher G maneuvers but it will still lean throughout the flight. While uniflow is the solution, it certainly can be hit or miss using a Fox. It doesn't make much sense as to why that would be, I can only say that out of all the engines I run, Fox .35 stunts are the most problematic to get working on uniflow with the uniflow pipe directly to the atmosphere. I've had them work better using muffler pressure to the uniflow pipe. It really depends on the plane and the vibrations of the plane. Seeing this is a full bodied plane this certainly suggests to me that one would have a  better chance than a profile. I don't know this plane well enough due to not flying OTS or the likes  to comment on it. I will say that if there's a remote chance of canting the rear of that tank outboard within the fuselage it  would certainly be a positive thing.    Ken

Cribbs74 wrote:Cool model that I was lucky to see fly today. For as old as the design is it has some unique features, such as a semi built up leading edge and a removeable wing. Pretty agile too! powered by a Fox .35 massaged by Lew Woolard. Here is a short video with a very close call when the engine shuts down at a very bad spot!

Nice save by Doug! Glad your Ring wasn't damaged Ron. Were you running a Fox too.. or an OS? I can't remember

Ken,

I started taking a video about a minute or less into the flight. Can't say how new the Fox is either. Pretty sure the prop is a 9x6 wooden job.

Maybe Doug can answer your questions.

Roddie,

The Ringmaster sports a 1952 Model Fox .35

It's a safe bet to say that of I am flying something it has a Fox or Cox on the nose. I have other engines, just a fan of Fox. They take some fiddling or in some cases reworking to run well and when set up correctly they can be CL Nirvana. When they don't run right they can be real nasty and cruel little beasties. I am going through a love hate relationship with a 1954 Fox .35 at the moment. Ken is helping me to get it set up right.

Ron

I have to say I truly like Doug's paint schemes. A great imagination and very nice craftmanship, two thumbs up!!!!!!!!

Doug loves his purple!

I grabbed a roll of lime green Ultracote off the shelf at the hobby shop where he works a couple days ago. You should have seen his face!

Thanks, guys!
This plane and engine combination is still in the first few flights phase. The video may have been only the 5th or 6th flight. I'm still finding the needle setting and propeller which work best on this plane. I have Fox .35s on several different airplanes, and they all seem to like a different propeller, to fly better: One propeller doesn't work best on every airframe, with that engine. Some need a 10x6, others a 10x5, I have one with 11x4. This is a 9x6, and a step in finding the correct one.
The fuel is 5% nitro 25% castor, with no synthetic oil in it. The flights with the Box Car Chief have been rather speedy- lap times faster than I desire. I will get them slower, with the right prop and needle setting. Four second laps on 60 feet of line, just isn't what I'm into. The Trike Magician I flew that day, has a Fox .35 "Gold Edition" powering it, and it does nice, slow laps. It is a heavier airplane, too! It also sports purple trim!
Yep, there's some tweaking still to do on the BCC, but it's gonna get there.