There is already a F1D-beginner class. It used to be called
F1D-beginner, but more recently it was re-named to F1M. The models can
be built to be competitive without exotic materials, using only
balsawood. Hobbyshop wood goes all through the construction, except that
the body tubes are more easily made from special indoor wood. I have
made models with fuselages sanded down from hobbyshop stuff, it is
possible, but a bit tedious.
Here in Finland we have multiple F1M's, and only a few F1D's, so the
models share the airspace. Collisions are common, but an F1M-F1D
collision poses no greater risk to the latter than does a F1D-F1D -one.
That is, no damage usually takes place.
F1M is easier to build, as the minimum weight is 3 grams, double that of
a F1D. The model is almost as big as a F1D, so flying weight is not much
larger. The construction is quite similar to a F1D, so tubes need to be
rolled for fuselage. For the rest of the construction, balsa wood is
sufficient. You guys in the US may be distracted with Bills carbon
construction, but I may assure you that it is totally unnecessary. Wing
spars cut out of 1mm balsa sheet, and 2.5 to 3 mm tall at the wing
center section, are good and stiff for consistent flying. I have never
used anything but balsa for my F1M wings.
Another advantage of F1M is that the motor minimum weight is 1.5 grams.
Thus the rubber quality and handling are not such super-critical as they
are for F1D. Impressive flight times can be achieved with recent Super
Sport rubber. But, the class allows the use of a VP prop, so you can
also learn the secrets of building and adjusting such delicate
instrument before moving on to F1D. The higher minimum weight allows the
F1M VP mechanism to be built larger and heavier, and easier to handle
(300+mg is perfectly OK) that those for F1D, so you can manage that more
easier. No exotic materials needed for F1M VP mechanism either, even
nylon M2 bolts are quite sufficient for the adjusting screws!
For the rawest beginners, we have made a further restricted class,
F1M-limited, for our local use in Finland (the rules made along similar
class in Germany): restricted length of fuselage, so solid wood can be
used, and ban of VP, so solid balsa prop is OK. That makes a nice path
from SciOly type models towards F1D: first a F1M limited, then a larger
F1M with fixed prop, then replace the prop with VP, and you are almost
ready to move onto F1D. I have given courses on the three steps of F1M's
here in Finland, and we have a couple of new guys on the climb towards
the top tier...
Later this summer I had a drawing of my F1M "course model" published in
INAV. Let he heartily recommend that as a good and solid design for a
beginner, as on a previous course we had 15 guys build them over a
weekend, and almost all got their models flying on Sunday afternoon.
Most flew straight off the building board, and several models made over
10 minutes on their first outing. With a fixed pitch prop, in a 18 meter
hall!
-Tapio-
On 28/11/2017 3:53, leop_at_lyradev.com [Indoor_Construction] wrote:
> There has been some concern about how to introduce young (and not so
> young) fliers to the F1D class. The usual method is to start with
> “simpler” classes and proceed along to F1D. One problem with this
> method is the rule restrictions of many classes, especially the
> material and design limits, make for planes that are not only
> difficult to build to the minimum weight and the needed stiffness
> without careful and costly material selection but also are difficult
> to set up and fly with the basic design limitations. For example, LPP
> class planes may be easy to build but their flight characteristics
> take expert attention to fly at the highest level. F1L’s are nice
> planes but the very best wood is needed to build a minimum weight
> plane with the stiffness needed to fly well especially in higher sites.
- application/x-ygp-stripped attachment: stored
Received on Tue Nov 28 2017 - 05:58:52 CET