Amps and Fins

[Sqwidge]

Firstly, Whats the deal with Stability fins? once you upgrade them to say carbon and they have holes in them, i dont see them serving a great purpose so with this though i removed my horizontal fin.
Is this going to affect my flight any? and if so how?
What does the vertical fin do apart from keep the tail rotor hitting the floor?

Secondly, does anyone know if 3 ino lab digital servo's, a 401 gyro, and a s9257 will cook my stock 25 amp esc?

[Holst]

I was wondering the same thing about stability fins the other day.
I could do with saving some weight on my tail as my heli is a bit tail heavy at the moment.

As all helis seems to have them they must do something.

I did think that they were to ballance out the wash on the canopy with the wash on the tail.

[waveydavey]

Stops your tail rotor hitting the floor and adds stability in backwards flight. A lot of guys remove the horizon fin, don't know why but I wouldn't advise removing the vertical.

[J3DI]

The solid fins are actually a hindrance in backwards or 3d flight, so the less surface area they have the better for 3d. The only pupose of the vertical fin is as you say, to keep the tail blades out of the mud! The horizontal fin can be removed to save weight and improve 3d flight.

[Holst]

Then why do all heli manufacturers seem to fit them?

Surely there is some benefit?

Will the fin add some stability?

[Sqwidge]

My horizon fin came off yesterday and looks better for it, i notice noone has answered my second question lol is this a bad sign?

[moyesboy]

Amps
Depends on the spec of the BEC in the ESC. Usually overloading the BEC doesn't burn anything, what happens is the voltage collapses and the receiver stops working. Once the receiver stops working the servos stop taking current (and the ESC cuts power), the BEC cools and starts working again and the servos start working again. So the effect is power going on and off and loss of control...

Test the setup by loading up the servos to see if you can brown out the BEC. yuo can put a voltmeter on the BEC power and see what is happening to the ESC. Usually a 3A BEC is only capable of 2A continuous....


As regards the vet and horizontal fins - some helis tend to have a nose down tendancy in fact forward flight (notably raptors). The horizontal stab can help with this. however if you are flying just as much sideways, backwards and upside down then it becomes useless and on 3D specific helis it doesn't have much surface area - its merely an outline or is very small. Its only there to help see the roientation of the heli.

The vertical fin does keep the tail blades from grounding and is essential for that. 3D pilots often cut it down to a thinner outline as it tends to cause travelling manoevres with the heli rotating to whip with the wind due to weathercocking.

[Tom Burgess]

The fins can also help with orientations

[SRH990]

When we only had gyros that were spinning wheels in a box (yes really!) the solid tailfin helped forward flight as the tail tended to follow the direction the heli was heading, no heading hold in those days, it was also there to keep the tail blades off the ground, as moyesboy says. It could be a pain when hovering as the heli really only wanted to hover nose up-wind but as we didn't do a lot of backwards & sideways flight the solid fin suited.

Fast forward to today and we have heading hold gyros, I had to adapt to these as I didn't use much rudder at all in forward flight, and we want to fly backwards, sideways, upside-down etc. so a solid fin is a hinderance, that's why they are mainly fresh air now and are really only there to protect the tail blades.

Quick UK now sell boom stay brackets for a few helis without any provision to mount a horizontal stab and with current flying trends they are a pain. If you notice full-size helis have both a vertical fin and a horizontal stab, talk to a full size heli pilot and he'll tell you he doesn't use the rudder much in forward flight and the stab helps to prevent the heli pitching up & down in forward flight, if you notice the Blackhawk has a moving stab, this helps even more.

[Sqwidge]

Thanks SRH, my horizontal fin is carbon so had lots of holes cut out of it for styling more than anything so im guessing me taking it off wont make a huge difference, maybe a click or two extra on back trim