Run time for BabeBee .049

Thats it? Sure seemed longer! Wouldn't think 2-3 mins. woud make me TOO dizzy.....err....dizzier

Hi Bee, you can partially fill a 5cc tank, and
increase as you get your confidence back.
In no time,you might be looking for an 8cc
tank.
Have fun,
Bob

Thats what I was thinking Bob!

From my experiences, 2 minutes is about it for a standard 5cc tank. Also to note, the higher the percentage of nitro, the shorter the run time as well.

And I thought 5 min RC flights were short!

You mentioned dizziness, which implies the engine would be for CL use. I flew the Baby Bee on CL back in the early 1970's. It was the standard engine of the time for half-A sport use. Yes, flights were dizzying for the some 2 to 2.5 minutes, but at 3 second laps was the most I could stand. This was on the standard fuel of the day with 15% nitro.

When fueling you can tilt the engine so the fuel comes out of the other nipple sooner only partially filling the tank to shorten flight times.

For RC work the minimum I used was the Golden Bee which had the 8 cc tank. I got may be 3.5 minutes of flight time on my 36" Airtronics Q-Tee. My RC Bee with a larger capacity tank got may be 4.5 minutes of flight time, I used it on a single channel rudder only with auxiliary throttle 36" Sterling Minnie Mambo.

Of course if one wants more they can go to an RC Dragonfly or Ranger. They have the same tank as my RC Bee but with an extension back adding more fuel capacity. The Ranger is the muffled non-throttled factory version for Cox's ready to fly RC planes.

I say may be, because I never really timed the runs. Flying is too much fun to get caught up in the exacting art of timing the runs. I'd just fuel up right away, restart engine and keep flying.

OhBee

found you
got your address
see you have been here for more than a minute

wink
grin

OhBee wrote:And I thought 5 min RC flights were short!

I am an RC flier and use COX engines with no integral tanks (most often TD-s and Killer Bee clones or similar reedies), so I have never tried this, but if you plug one of the fuel nipples on the Bee tank - actually use it for filling the tank with the nose of the plane pointing down in order to drive air out through the other nipple, then plug the silicone filling hose attached to it - , and connect the other to an external balloon tank or similar, than your on-board fuel capacity and RC flight time can be extended at your discretion, depending only on the volume of additional external tank thus connected...of course filling this combo tank and making sure air pockets are not left in the tanks after filling  needs to be assured for an uninterrupted flight.

Alternatively you can fill the combo through the external  tank , and use the other nipple on the Bee tank as a vent, then close  this nipple when both tanks are full and air has escaped through this nipple. Venting during flight will occur through the ventline of the external tank. Or, if ballon tank is added fro external capacity, only the ballon volume will be available to feed fuel to the engine, with the balloon gradually collapsing as the fuel is consumed, the integral tank capturing the remaining 5cc fuel in it, because it cannot collapse.



The above is a bit weirdo solution but allows longer flight times on a Bee without cannibalizing the tank (some folks drill a hole in the aluminum bowl and connect the fuel line of an external tank led through this hole to the  internal fuel nipple on the Bee back plate.)


I use un-pressurized ballon tanks and 8-12 minutes of RC flight times are just quite fun and not yet tiresome.

I have swapped all my COX engines for NORVELs on my wet RC stuff and use Fuji film can tanks.  Flight times are 7 to 9 minutes which is plenty for me.

One of my club buddies is now flying some .049 stuff, but was a little disappointed with the short run times. I gave him a Sure Start and made up a Fuji tank for him to try when the weather here becomes a little more cooperative. Fuji tanks will hold around 28 cc's.

Back in the day I had a Lil Jumping Bean C/L with a small wedge tank. First flight I filled it...bad mistake! That was WAY past 2 minutes! Finally had to wander off course and ground it in the weeds. Now that was a dizzy flight!  I would love to do an .049 RC plane!  Taught  myself how to fly RC 4 yrs. ago ,but really not thrilled with electric motors and the electrical issues I've had.....and battery problems. I'd rather burn Nitro!

For you, OhBee:

https://youtu.be/EhcS78d3nlg

Jim...thats quite the setup ! Love it....In the summer my motorhome is kinda my hobby shop. I was messing around with one of my long dormant BabeBees...just assuming it wouldn't start anyway...And it fired right up. Had to make a hasty exit! Still have a faint castor oder in there! ...Which isn't ALL bad

This may help. a 5 cc tank is 0.1691 or 1/6th ounce. An 8 cc tank is 0.2705 or a hair over 1/4th ounce.

Here's an article where we are discussing the merits of the RC Bee, Dragonfly and Ranger engines:

RC Groups: Cox .049 Ranger Product Engine

My tanked run IS a bit short. I tilt the engine so the fuel pickup in the tank is dead bottom. I do this to consume all the fuel in the tank. However, since the vent is also not straight up, the tank doesn't fill completely. There will be an air bubble just above the vent hole.

Stock, the fuel pickup terminates in the tank at about 8:00. This is so the pickup is in fuel while the model goes Roundie-Roundie, and the fuel rides up the side of the tank a bit.

If the engine is straight up/down, then the fuel is dead bottom, and the pickup will not get down to the last drop.

So I bet I sacrificed about 15-20 seconds run-time. No big deal if just bench-testing. It sure beats having to drain the tank if that last little bit.

Pics can provided if you want them.

FWIW-- The other day when I had my syringe out for a couple of projects, I measured the capacity of a Cub .049A plastic tank at 7cc, not including the additional cavity volume on backside of crankcase. I guess the total would then come to at least 8cc.

Perhaps Cox International and Ex Model Engines manufacture a fuel tank extender in near future. I think that it will be a good seller.

I've got one of those Kavan tank extenders for the 8 cc tank, don't know final capacity but perhaps may be makes it 11 cc? I think that is what you mean? Here they are on E-Bay, time to snag them while the going is good for only $15 + $3.50 shipping US from gatafish:

E-Bay: 2 Kavan Bee Tank Extenders

(0.8cc) refers to the .049 c.i. displacement of the engine. This extender goes on a Baby Bee with a 5 cc fuel bowl and probably brings total fuel capacity to about 10 cc.

Unfortunately doesn't clarify for which tank, 5 cc or 8 cc. I think the barrel length was same for both (been a while since I last saw in the Ace R/C catalog umpteen years ago). May be you are right.

Anyway, if one has 3-48 screws long enough they can trim (I think that's the size, not 2-56?), can make it work for the other. A little discussion occurred here: https://www.coxengineforum.com/t1475-kavan-tank-extenders

If for 8 cc tank, increases to 12 cc per that forum thread.

Yes, it will work on Baby Bee and Golden Bee with appropriate length screws. I've just never seen a Kavan unit packaged with long screws for a Golden Bee.