Futaba Servo Quick Guide

If you've spent any time browsing Futaba's web site, or your favorite online dealer, you've probably noticed the incredible number of servos available. It can be daunting for modelers to choose the right servo for a given use.

It turns out that for airplane applications, there's probably only two servos you need to consider. (If you're one of those very serious flyers with a 10 foot wingspan, 5 horsepower monstrosity, you don't need this quick guide anyway). That's because most planes call for either standard or micro size servos, although it's worth noting that not everyone seems to agree on what micro means. This table lists the two models to look for:

Futaba Analog Servos

Name:	S3114	S3004
Street Price:	$14 USD	$14 USD
Size:	Micro	Standard
Dimensions:	0.86 x 0.43 x 0.78"	1.6 x 0.8 x 1.4"
Weight:	0.27 oz	1.3 oz
Torque:	20.8 oz/in	44 oz/in
Speed:	0.10 sec/60 degrees	0.19 sec/60 degrees
Uses:	Park flyers, foamies	Larger planes, gliders
Notes:	Replaces S3110, more powerful than S3111 and S3113	Adds ball bearings for almost the same cost as S3003, much cheaper than high torque S3010
Digital Alternative:	S3154 ($31 USD)	S3151 or S3152 (each $30 USD)

Of course, check your plane's manual to find out what the manufacturer recommends. You can usually download a PDF version before buying. If they do require a mini servo, try the S3115, which is the best value in that size.

You can also try the Futaba Servo Selection Form if you have more specialized needs. It's a good way to compare torque and weight across different models. Fans of other brands of servos can check out Hitec's site, JR's site, and Airtronic's site to compare their offerings.

Is it worth going with digital servos instead? That's a topic for a whole other article. My recommendation is to stay with analog servos until you reach a point or find an application where you're not satisfied with them. However, if you're buying a new radio, you will find that choosing bundled digital servos will be only slightly more expensive than the analog package, so go for it.