Sessholvlaru

Picked up one of these 70mm RCBlitzWorks F-104's and it had arrived slightly damaged. One of the tip tanks was crushed, so I removed both of them (I like the plane better without them anyway). I also added a scale amount of anhedral as stock it has none. Upon flying it I notice a pronounced wobble side to side. I assume this is a byproduct of the anhedral since the non-modified plane does not exhibit this characteristic.

Any ideas how to cure this? The model does not have the ventral fin. Maybe it is bottom or top heavy? It is laterally balanced. Help!

Sessholvlaru

Here is a pic. Again, out of the box this jet had no anhedral. Put three flights on it today, and other than the wobble it flies great.

otrcman

You might try putting the ventral fin on. The short wings of the F-104 provide very little inertia or damping in roll, so any little disturbance will show up in roll before showing up in pitch or yaw. Airplanes tend to roll whenever they are yawed, so increasing yaw stability may reduce the wobble in roll.

The other thing to remember is that full sized F-104's wobble some if the stability augmentation is turned off. You could add stability augmentation by putting a simple rate gyro in the roll channel of your radio. The real airplanes had basically the same thing as what we call a rate gyro. Only difference is that they had gyros for all three axes.

Dick

Lnewqban

Some additional wingtip weights will add roll inertia.

rmh

Weight additions on this size stuff is not really a great idea- the power to weight is critical.
The added anhedral is also a problem on this size
We fly a lot of this small stuff . the extremely low weight, makes em work in the first place -
a couple of small plates -one on each tip beveled to make tiny winglets pointed outward at about 45 degrees may work-
We used this trick to correct roll couple on larger models stuf in the 10-12 lb range.

JeffH

My Feedback: (43)

A flying buddy put the scale anhedral in his after test flying it stock. His rocked back and forth stock so bad he had to put a gyro on the ailerons. He cut the wings off and put the scale anhedral in, but we never flew it without the gyro. It does fly decent with the gyro, but being an F-104, I don't think it will ever fly what we consider "good".

Sessholvlaru

Is it the same model as mine? Mine flies great and the wobble does not affect how it flies, it just does it. It has surprisingly good low-speed characteristics and it (relatively) easy to fly.

rmh

yes- it is very low in aspect ratio (short n stubby wings)
these will not "snap out" - just settle rapidly .
all of my planes which are really fun to fly have very low aspect ratio wings and are extremely light and grossly overpowered .
I also have gliders but they are a different matter altogether.