I'm by no means an expert but having had a pretty active
combat season including a visit to the NATS, I have a few observations, which
may be of use to folks working on their winter building projects:
1)
Big wings are IN. The more wing area, the better, it seems, especially evident
in scale. Any resulting slower speed seems well worth the tradeoff. Big wing
planes were vary dominant in scale winner's circles. In Open B, spans seem to
have settled in the 63-72 inch range. Don't see many wings shorter than this in
the winner's circle, and the occasional 80 incher shows up but has not been
shown to dominate. Roll rate seems to be acceptable up to 72 inches but may be
a problem beyond that.
2)
Short fuselages are IN- nose and tail moments seem to be decreasing with
overall lengths from firewall to elev hinge line less than 20 inches, often
much less. Have also seen some flying wings, which seem to have exceptional
turning ability. I shortened the fuses on my Open planes last year and found
that there was no deterioration of any of the easy flying qualities of the planes;
in fact I plan to go shorter yet. Pitch response is improved, and weight is
saved.
3)
Larger VSTABs are IN- with the longer wings comes severe yaw when a streamer is
stuck on the tip. A big fin will really help to offset this and even with my 72-inch
planes, a streamer on the tip was quite manageable. Larger fins were the single
biggest improvement I made in my open planes last season, and I plan to go larger
yet this year. I would suggest a minimum of 65 square inches, though you can go
much larger. The weight increase is minimal compared to the performance
benefit.
4)
Sub fins are IN- I have not tried this yet so I am going on what I have heard,
but a sub fin will help keep the wing from blanking out the VSTAB in high AOA
flight, which should improve turning ability and stall resistance. Also
improves knife-edge flight, which helps in pursuit. Definitely adding sub fins
to this winter's projects.
5)
Selig 8036 airfoil is IN- AJ uses it so it must be great, right? Dr. Evil
changed to it and claimed it improved the turning of his planes too. Thunder
has also tried one and loves it. Can't wait to build some myself. This airfoil
has some negatives to look out for. It is thinner so wings are slightly weaker-
chords have been increasing to add thickness to offset this. It is very
sensitive to aileron trim, you must be neutral to slightly reflexed- NO CAMBER
or the pitch response will suffer dramatically. And the ailerons are prone to
flutter, make sure your ailerons and linkage are STIFF. But sorted out, it is supposedly
the best turning airfoil out there right now.
5)
Lighter construction is IN- planes are turning tighter than ever, and the
heavily armored battlewagon is yielding to the more lightly armored, but
tighter turning, construction. Seeing a lot of wings that are only Dow HiLoad
40 foam, 1/8 f/g rod spars, 1/4 PP rod LE, and covered with bi-di tape or plain
nylon. Much faster to build than other forms of construction and lighter,
though more prone to midair damage. But the performance of planes has gotten so
high that a few ounces saved is making a competitive difference. I built battlewagon
wings last year, and after a full season of combat for both Brian and me, ALL
our wings are still intact! Despite this, we were still knocked out of the air
many times- battery leads disconnected, elevators disabled, engines knocked
out, etc. So a tough wing, while nice, is no guarantee that you will survive midair!
I may build lighter wings this winter!
6)
Power is IN, seems just about every serious competitor is using tuned exhausts!
Hard to see where more power is any kind of detriment, performance-wise!
Personally, I wish tuned mufflers were outlawed as I feel the performance level
is too high, but I apparently am in a small minority. So to try to stay
competitive, I use tuned mufflers. See my other Flightlines thread on this
subject.
6)
Bubbleless fuel systems are gaining in popularity- with the rigid fuselage construction
of some planes, plus the higher rpm levels being run, more folks are using
bubbleless systems to improve engine runs. They are more difficult to maintain
and fuel, but their performance benefit is well worth it if you have a foaming
problem. If your engine runs fine, they will be of no benefit, but if you have
erratic runs or late-heat leaning problems, they may help.
7) Having a great spotter is IN- I feel so much better when I have Brian there to spot for me, he settles me down and helps me find targets and comes up with some great suggestions and tactical tips while I am concentrating on keeping my plane in the air! AJ has his wife spot for him; see his excellent tips and tactics article. Unless you have the innate capabilities of Dr. Evil, a spotter will really help you out!