"I should bring you up to date on the DOODLEBUG Family
Tree. The original DB was published in the March 2002 Flying Models
magazine. It caused a slight ripple in interest, and several guys sent
pictures of their copies from the magazine plans (CD158) Carstens Plans.
Photo by Bill Netzeband
Family of DoodleBug control line aircraft. Apparently
they reproduce at the same rate as other kinds of bugs.
I then decided to scale the 580 sq. in. plane down
to .049 engine size. My first try led me to a 256 sq. in machine that was
way under-powered (I have had several 240 sq. in 1/2A's that flew well).
Nonetheless, the second guess at 10% linear reduction led to a neat 1cc plane
(207 sq. in.), and the third iteration of another 10% finally got a legitimate
1/2A plane at 168 sq. in."
"I published these three in the February 2003 issue
of Flying Models, and their plans are CD187 at Carstens. You have already
noticed that there are no 330's yet."
"I was searching for a logical sequence to scale CL
planes up and down based on the ratio of the 2 engine's displacement. With
some help from friends, the key was the 2/7 root of the ratio of the
displacements. There are a couple of other things that have to be
considered to make the planes viable in the CL circle, involving velocity, lines
length and weight."
"The proof for the method lead me to build three
more DOODLEBUGS, the 440, the 330 and the 100. These were specific to the
.25, .15, and the .020 engines, coming down from the 580 with a .40. This
method also faired in the three planes that were designed by iteration."
"Actually, I threw in a flapped version of the 580,
which is a real barn-burner. These were offered to Flying Models earlier
this year, but have not yet been bought. My 440 has a nice OS25LA, and is
happy. The 330 is happier with a McCoy 19 series 21. Finding a 15 that will
function well with a muffler isn't easy."
"Let me hasten to add that I don't plan any more
DOODLEBUGs, at least in the CL arena. Now there COULD be something for RC?"
and received from Wild Bill on 05/28/2005...
Since Flying Models was apparently tired of
Doodlebugs, I gave the text and photos of the last 4 versions to STUNT NEWS, and
the article and scaling procedure was published in the March/April 2005 issue,
on Page 50. GUESS WHAT. I was mistaken in stating I would build no more
As Paul stated in the 330
photo caption, " these bugs seem to breed just like regular bugs. I have the
airframe and part of the controls package in process in the shop for the Cox TD
.010! Comes out to a 67 sq. in. machine, and as of this afternoon, the airframe
lumber has been shaped and is ready for assembly. Looks like the controls and LG
will weigh more than the airframe structure, and with an engine at 0.9 ounces
the finish weight lurks just over 2.6 ounces.
I am now toying with going back through the line of
flapped versions, but don't order plans yet. It probably won't happen. My
shop is overrun with finished models. Of course, I have a solution (but painful)
for this condition.