Dynon Pitot/AOA location

Until now, I had been planning to locate my Dynon pitot/AOA tube just outboard of the aileron bellcrank, simply because that's where the SafeAir1 pitot mount instructions suggested. However, Dynon's website suggested the normal location for Van's pitot (bay inboard of the bellcrank) worked as well in their testing. Since I still haven't found a way to run the AOA pitot lines past the bellcrank (in a way that doesn't leave me a little uncomfortable about potential bellcrank interference), is there any reason not to put the pitot tube in the bay just inboard of the bellcrank? It seems that this would still be easily accessible through the bellcrank inspection cover and would no longer require running the tubing through or around the bellcrank. Am I missing anything? Thanks.

Just a thought (question) here...

Would it be safe to use slightly longer bolts to attach the bellcrank brackets, so that you could put the bolt throught some adel clamps to secure hoses running above/below the bellcrank assembly?

Longer bolts usage

I think that if you decide to do that, use the longer bolts, washer and nut as per plan, THEN add the adel clamp and a second washer/nut to hold the clamp between the first nut and the second one.

Mike S

RV7Factory said:

Just a thought (question) here...

Would it be safe to use slightly longer bolts to attach the bellcrank brackets, so that you could put the bolt throught some adel clamps to secure hoses running above/below the bellcrank assembly?

Click to expand...

I've looked at that (and Van's indicates it's OK to use an Adel clamp here), but I don't really like that set up for me. As recommended by Van's, I used the original Van's pitot line hole as well as the adjacent tooling hole. Given that, both holes are in the center forward most portion of the rib and would run right under the bellcrank if I were to run the lines straight through. Bending the lines around to adel clamp them to one of the b.c. attach bolts will put a pretty tight bend on one or both lines and would probably require another attach point elsewhere in that bay to hold the lines away from the b.c.'s movement. Thus, I'm really hoping someone will just tell me that they put their Dynon pitot just inboard of the bellcrank and have lived happily ever after since.

I'm following the crowd, putting mine just outboard of the bellcrank. I can't think of any problems with inboard. Just make sure the pitot isn't near the tiedown ring (don't want to get it caught on a tiedown rope) and won't get in the way if you decide to put in a servo for an autopilot later.

Dave

Davepar said:

I'm following the crowd, putting mine just outboard of the bellcrank. I can't think of any problems with inboard. Just make sure the pitot isn't near the tiedown ring (don't want to get it caught on a tiedown rope) and won't get in the way if you decide to put in a servo for an autopilot later.

Dave

Click to expand...

Thanks Dave--
Do you have any pictures (on your website or otherwise) showing how you routed the 2 tubes around the bellcrank?

I hadn't thought about the tie down issue (but should have). Still, with the short RV wingspans, you're almost guaranteed to be running the tie down ropes up from the ground and inboard to the tie-down ring. Thus, the pitot being inboard of the bellcrank/tie down ring, rather than outboard might be a good thing, right? In any case, it's closer to where Van's locates theirs.

For those who have Digitrak or Trio, doesn't the servo go in the bellcrank bay (preferably)? Perhaps another reason to have the pitot lines terminate at the bay inboard from the bellcrank?

Again, I'm just thinking aloud. I haven't cut my bottom skins for the mast (or yet attached the mast) so I can still change my mind about all this and looking for reasons to.

Thanks. I appreciate the ideas.

I haven't run the tubing or wires yet. That'll be part of the infamous "last 10%". I know I've seen routing around the bellcrank on someone else's site, but I can't remember where right now.

True, it does seem like inboard might be better for the issues I mentioned. Unfortunately, I've already cut the hole for the mast, so I don't have a choice.

Dave

How I'm doing mine.

The tubes are sheathed inside larger tubing. That makes them less flexible and should give good chafe protection.

Routing the pitot and AOA lines

Here is a picture showing how I am routing my pitot and AOA lines. I am planning on using Dynon's heated pitot if they ever get it to market. I was initially planning to run all aluminum tubing straight to the fuse, but I may put coils in the aluminun tube from the pitot to shed pitot heat and then continue from the bulkhead fitting with plastic tube. I would like to have positioned the pitot inboard of the bellcrank, but I had already run my wiring conduit and with the pushtube,it gets too busy just on the other side of the bellcrank wing rib. Positioned outboard of the bellcrank bay gives me plenty of room. Only draw back I can see is potential tie-down conflict. Of course, I'll get with my local tech advisor to see what he thinks.