Trim/Flap Servo & Indicating Question

Kyle Carroll · #1 02-05-2014, 04:38 PM

I was wondering about Van's optional trim servo. I noticed that the Ray Allen servos have a nice indicator that can be purchased with it, that way you have an easy way to see trim position...does the servo that comes optional with the empennage kit have the ability to be connected to an indicator and/or the MFD, assuming it supports trim position, or would I need to purchase a different servo instead?

I'm also wondering the same thing about flap positioning. Does the kit come standard with electric flaps, or manual? I couldn't find anything about it in the order form. Again, if it does come with electric flaps standard, would those servo's be able to integrate with an indicator and/or MFD? I also plan on using the Van's Flap Positioning System.

Thanks!

rbibb · #2 02-05-2014, 05:31 PM

FWIW - I wouldn't bother with the flap indication system. There simply isn't any need for it. If you want some indication for partial flaps some tape on leading edge would suffice but I've never felt the need for partial flaps in my RV.

Trim indicator is useful so you can determine neutral position for takeoff. Beyond that I never look at it the rest of the flight.

Kyle Carroll · #3 02-05-2014, 05:48 PM

I suppose I really don't need indication, I just think it would be a neat thing to have show up on the MFD's. If I had a way to install a "Takeoff Trim" button similar to what we have on military aircraft, it would eliminate the need for the indicators, as it would place all trim tabs to their neutral state.

Toobuilder · #4 02-05-2014, 06:41 PM

Just keep in mind that "takeoff trim" position is highly load dependent in the -8. What works solo does not work with someone in back.

AaronG · #5 02-05-2014, 06:59 PM

The Ray Allen trim motors have a position sensor built into them. You can run the output wires to one of their LED indicators, or any MFD that supports trim indication. My experience is that the Ray Allen LED indicators break, so I would go with MFD if possible. On my 8A, I look at the tail to set trim on takeoff, and then trim for stick loads in flight. Never actually use my LED indicator.

The flap motor doesn't have a position sensor. If you want to know flap position, you will need to install a seperate position sensor. Or just install one of the flap position systems that check for position. I have neither and don't miss something extra to break. Motor sound tells me if flaps are full up or down, or I look out canopy.

Aaron

Kyle Carroll · #6 02-05-2014, 07:07 PM

Quote:

Originally Posted by AaronG

The Ray Allen trim motors have a position sensor built into them. You can run the output wires to one of their LED indicators, or any MFD that supports trim indication. My experience is that the Ray Allen LED indicators break, so I would go with MFD if possible. On my 8A, I look at the tail to set trim on takeoff, and then trim for stick loads in flight. Never actually use my LED indicator.

The flap motor doesn't have a position sensor. If you want to know flap position, you will need to install a separate position sensor. Or just install one of the flap position systems that check for position. I have neither and don't miss something extra to break. Motor sound tells me if flaps are full up or down, or I look out canopy.

Aaron

Good information. So basically, if I do want to add trim indication, my best bet would be the Ray Allen servos then. As far as flaps, the it looks like Van's sells a Flap Indicating servo for only $36 or so which can be wired to the MFD. So am I correct to assume that the -8 kit comes with a flap motor, as opposed to manual?