Global Goodyear - F2G ?
Creating International
Rules for Goodyear Racing.
By Göran Olsson
October 1998
My Cosmic Wind (Now in a dump somewhere in England, after being snatched
out of Håkan Östman's Volvo.)
It is quite clear that at the present level of performance F2C is
totally unreachable for beginners.
Especially on the pilot side, where a high degree of skill is necessary,
safety being a critical point. Therefore, for the survival of the F2C
class, promoting a simplified form of racing is momentous. In many
countries "Goodyear Racing" exists, and already serves this purpose,
although the rules differ. To keep competition in such a class at a
healthy turnout, and even expand it, we could benefit a lot from unifying
the rules. Interest would be greatly stimulated by having contests,
comparison of results, and equipment availability on an international
level. The scope of these ideas has gone from European to Global and even
further to defining a provisional FAI class, "F2G". In such a case the
name "Goodyear" probably cannot be referred to, as FAI would shudder
at a brand name.
Name suggestions are welcome! Maybe "Formula 1/8 Racing"?
The next step in expanding the scope is the idea that such a class could
replace the F2C junior competition at the World and Continental
Championships. The physical contact in F2C makes it unsuitable to match
juniors and seniors, as is done today.
A few important views of mine, in response to suggestions already
made by others, and to existing rules:
General:
Speeds should be much lower than F2C. Target: No models with faster 10
lap times than 22 s, bulk at 25 s, all normally faster than 28 s if set
correctly. There must be no limit on speed as such, or other penalty for
high speed, since this is alien to the idea of racing. If speeds go up,
rules should respond, first hand by reducing engine intake area. A
suitable step is .2 mm of the diameter. (see below) If we get "F2G", such a
change should still be made on the national level without waiting for a
FAI decision. We may end up in differing intake rules, but this is a
minimum inconsistency.
The rules for "Texas Quickie Rat" have this text, and something similar
could be used for F2G:
Objective:
To provide a racing event that may easily be flown "three up" and which
employs relatively inexpensive and easily constructed control line racing
models. To encourage and "promote the success" of the "average" control
line flyer in control line racing competition.
F2C rules should be used as a template, and everything about conduct,
safety, and so on should be applied.
Model Design:
-
There must be a smooth transition from existing national classes - keep
model specification similar: 1/8 profile scale of real "Formula 1"
racing designs (where the wing area requirement is 66 sq.ft.)
with a clearly defined tolerance, +-5%. The rules should specify which
dimensions this tolerance applies to. No wing or tailplane
area restriction necessary other than the scale tolerances. Keep the
extra allowance for a larger tailplane, +25% area. Maximum
fuselage width is not important, just specify that engine and tank should
be mounted on a flat vertical surface and exposed to the airstream. No
spoilers fore and aft of engine. Allow older models that may differ in
some way to compete for two seasons under the new rules.
-
Mandate paint on whole model including tank, with canopy in contrasting
colour. Also racing numbers on both fuselage sides and one wing tip. Just for
more attractive model appearance.
-
Don't mandate two-wheel landing gear, but rather the opposite: A
monowheel simplifies holding the lines on the ground during pitstops,
improving safety.
Propulsion:
-
High quality engines engines suitable for racing must be allowed. No bans
on ball bearings or schneurle porting, but firm limitations in other
respects. 2.5 cc capacity to begin with. To achieve good learning for
F2C, make diesels mandatory. This automatically takes care of hot
fuels and pipes. Intake area restricted to meet the above speed target.
An area of 12.57 mm2, corresponding to 4 mm diameter is a
preliminary suggestion. Reduction of existing carburetors easily done by
inserting a piece of brass tube. Carburetors with a central spraybar
should have the area calculated from the spraybar and venturi diameters.
(For a spraybar diameter of 4.0 mm, the venturi diameter becomes 7.06
mm. You can download a MSDOS program that makes this
calculation.)
Ban on pressure fuel feed is unnecessary, as there is no gain from it
with an intake area this small. Intake plenum chambers to cheat this rule
should be disallowed the same way as for F2D. How to deal with sub-piston
induction? Disallowed, but see next item.
-
Engines meeting certain criteria for low-tech design could be allowed free
intake area (including sub-piston induction).
Such as: Engines having two or more exhaust ports arranged
symmetrically along the cylinder perimeter.
The opposite also possible:
Engines having aluminium piston could be given an inlet area penalty.
Should rear intake engines have a larger intake allowance? (No)
-
A list of allowed engines is impossible on an international level - no
brand names could be mentioned in the rules. Maybe "any engine design
used in a F2C championship the last five years" could be banned, or given
an added intake restriction.
-
No restrictions on engine rework.
-
Engines with features aimed at reducing their aerodynamic drag are banned.
-
Propeller material restricted to nylon or glass filled nylon. No
restrictions on diameter or rework. This is the most important rule to
limit the cost of racing. Don't use the word "commercial" (as I have
seen) in the rules! Aren't Russian carbon F2C props commercial??
-
Silencers? Will limit both speed and noise, but to get reasonable
starting calls for more expertise than in F2C of today, so: No
silencers.
Gadgets:
Ban expensive or work intensive "killer" gadgets! BUT: I can think of none
that needs to be banned, though, as soon as intake and propeller are
restricted, except for state-of-the-art F2C engines! Avoid unnecessary
bans on equipment that gives no great flying speed advantage! Therefore
allow:
- tank valves
- automatic prime
- quick fill systems
-
any landing strut design
- internal leadouts + control mechanism
-
any weight (no lower limit)
Since it is clear that very simple designs, such as three
tube tanks, piano wire landing gears and outside controls work fairly
well and has no big speed penalty, why deny someone the moderate
advantage that a few hours' work on more advanced solutions will give?
Safety:
-
Mandatory safety wire between engine crankcase and bellcrank, .5 mm dia.
-
Contest director may disallow a model that appears to be unsafe.
-
Multi-strand lines of same size as F2D (.385 mm), 7 strands minimum.
Good availability and reduction of speed.
-
Pull test 10 kgf (100N) fixed value, for simplicity.
(A 700 gram model going 22 s/10 laps will pull 9.3 kgf.)
-
Shut-off mandatory. Type not restricted. The shut-offs made and sold for
F2A are cheap items and useful here.
-
T-bar comp screw not allowed. Old style diesels easily modified just by
removing the bar.
-
4 mm (not 5) minimum radius on spinner nut.
No protuding skids and so on.
Race organization:
-
Two pitstops for 100 laps, five for 200 laps. An increase in pitstop
count is possible. Three and seven, respectively?
-
Tank size free but filling up on pitstops mandatory.
-
In domestic contests pilots having a contest flying experience of less
than 10(?) heats should have right to two-up heats if they wish,
otherwise three-up heats. Final always three-up.
-
In domestic contests the contest director should be allowed to seed
teams in different heats by their experience - safety takes precedence
over fairness.
-
Contest run in four rounds, the sum of the two best times qualifies
for the final, and the single best time determines the place outside the
final.
(This system is used in Sweden for F2C.)
Avoid semi-finals that leave some teams as watchers only.
-
One timekeeper/lap counter per team is sufficient.
Send your views to
me!