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PH Aviation flap actuator in an RV-8?

N546RV

N546RV

Well Known Member
So tonight's deep dive into hypothetical land has revolved around my flap system - do I want a flap controller, or just limit switches, or just one limit switch, or nothing at all, or blah blah blah blah. Then I ran across what seems to be a fairly new product, PH Aviation's upgraded flap actuator.

While not cheap, I like that it incorporates basically all of the features I was looking at adding externally, with a bonus of being able to drive a position depiction on the EFIS. However, I'm trying to think through the installation details. I've run across a few VAF threads about adapting the actuator to basically every model except for an -8.

The installation instructions do have a couple photos showing an -8 install, but no real detail. However, from a look at the photos, it looks like absolutely nothing is changed about the mounting. The upper bracket on the bulkhead is the same aileron bracket used with the factory actuator, and appears to be in the same location.

Does anyone have any knowledge or thoughts on this? Perhaps the -8's flap architecture is such that no modifications to the attach point are required to account for the longer actuator? (It does appear that the hole in the armrest has to be opened up quite a bit)
 
I installed one in my -8. So far, so good. I was experiencing the usual problems with the standard actuator. I liked the fact that the PH actuator incorporates the position sensor so you don't have to mess with that. A couple of points:

1. I mounted mine upside down relative to how the Vans actuator is mounted. The motor is mounted at the top. I did this so I have no moving parts outside of the arm rest and to minimize the hole you have to put in the armrest.

2. The mounting point on that end of the actuator is wider than the space inside the Vans mounting bracket by about 1/8". I used my Dremel to slice off 1/16" off each side of the mount and then polished it out. You might be able to make a replacement mounting bracket out of U channel aluminum or the like. In retrospect, I probably would do this instead of taking metal off off the mount, although there's plenty there.
 
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Phillip, Pat's Full Up Auto Stop kit would be worthwhile in an -8, as it would free your left hand for other things, like re-trimming. A solo RV-8 is typically trimmed far rearward for final approach, so during a go-around, the forward stick pressure requirement grows rapidly with rapid speed gain. I've never liked moving my right thumb from behind the stick (to trim) while forward pressure is required.

Nothing very wrong with the kit-supplied flap actuator, assuming you already have it. Thoroughly de-grease it before installation.

A flap position indicator on the EFIS? Build what you want, but I'd consider it a sure symptom of optionitis, given RV drivers come standard with dual optical sensors ;)
 
In re: a flap position controller, I personally would put that on a "gotta have" list. In my case, I use the VPX Pro which has that capability and allows me to hit the flaps switch once and the flaps go down about to the 50% point without having to worry about it. One touch on the switch and they come up all the way as well...No, it's not a required component but highly desired in my opinion
 
Initially, I wanted a controller as well with discrete positions - and that was one of the things that had me going with a VP-X - but after logging a bunch of Grumman hours, I wasn't at all bothered by just having an ON-OFF-(ON) setup, and holding the switch down to extend as I desired. I do still want to have the ability to flip the switch up to retract for go-arounds and such, but I don't personally feel that a flap controller (or, in a grander sense, the VP-X) are worth the money.

And to Dan's point, now that I've had a day to sit on the results of yesterday's marathon research session, I'm leaning towards the PH motor being overkill as well; the Full Up kit seems like a much more reasonable way to get what I want. Though some part of me keeps wanting a down limit switch, even though it seems that having the factory motor reach full travel and run on for a few extra seconds is no issue.

Long story short, this is what happens when I'm visiting the parents and spending my free time firming up my electrical system design...I start really wanting to answer detailed questions...
 
N546RV said:
...now that I've had a day to sit on the results of yesterday's marathon research session,.... the Full Up kit seems like a much more reasonable way to get what I want..... it seems that having the factory motor reach full travel and run on for a few extra seconds is no issue.....
Click to expand...

I reached the same conclusion and if the factory controller motor craps out then I?ll buy the updated PH actuator. For now I?m going out to the hangar and I?m going to count how many seconds it takes to go from full down to full up and memorize it. Next time I fly I?ll just count and release and see if that works for me for now.
 
Pilot135pd said:
Next time I fly I?ll just count and release and see if that works for me for now.
Click to expand...

Yeah, that's pretty much what the routine in the Grumman was. Run the flaps in three rough increments, each increment equating to holding the down switch for about three seconds. On final when I wanted to verify full flaps, I'd just hold the switch down while glancing out the window to confirm that the flaps weren't moving any more. Dirt simple, and no problem to handle.
 
According to PH's information, their actuator is nine ounces heavier than the factory one.
 
More reason to not do it until the factory one craps out. I’m trying to make the plane lighter and every little bit counts. I’ve personally lost 18.6 pounds since I made up my mine to lose some weight on October 1st and my goal was to lose at least 20 pounds by the end of the year, still hoping to make it ! Feels good not lugging around those extra pounds too.
 
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