What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Couple small random questions while on the fuse

RVFan671

Well Known Member
1) what can/should be used on the bolt shanks for the landing gear mounts. The bolts are pretty tight and I don't want them freezing over time. Anti sieze or grease are my thoughts but I don't want some galvanic corrosion somehow with various types of anti sieze.

2) for those who have put your comm antenna under the rear seats, what did you do for access? If I want to make an access panel that is flus it seems I'd need a 5 year old hand to reach in because the ribs are close forcing the access panel to be tiny. Pics of what you did might be useful here.

3) anyone dimple the rear seat pans (under the butt of the rear passengers) to use the countersink pull rivets versus the standard pull rivets that will protrude? Was thinking it might be nice to have all flush under there if I pull rear seats for a larger cargo area.

4) do I need to run my conduit before riveting the rear baggage floor pans? I pan to run the conduit along the side of the aircraft along each side and covered by the side panels that close things out.
 
1) what can/should be used on the bolt shanks for the landing gear mounts. The bolts are pretty tight and I don't want them freezing over time. Anti sieze or grease are my thoughts but I don't want some galvanic corrosion somehow with various types of anti sieze.
I agree with your concern about conductive anti-sieze. I haven't done the gear yet, but with the steps, I've applied some lithium grease that is designed for high pressure applications.
2) for those who have put your comm antenna under the rear seats, what did you do for access? If I want to make an access panel that is flus it seems I'd need a 5 year old hand to reach in because the ribs are close forcing the access panel to be tiny. Pics of what you did might be useful here.
I'm planning to install belly antennas under the baggage compartment with access panels to improve access.
3) anyone dimple the rear seat pans (under the butt of the rear passengers) to use the countersink pull rivets versus the standard pull rivets that will protrude? Was thinking it might be nice to have all flush under there if I pull rear seats for a larger cargo area.
I thought about that but am not going to bother. For big cargo use, I'll have a mat to lay down over the seats/bag floor.
4) do I need to run my conduit before riveting the rear baggage floor pans? I pan to run the conduit along the side of the aircraft along each side and covered by the side panels that close things out.
Almost certainly. I am at that exact phase now and have bought a bunch of conduit and am reviewing others' build logs for conduit routing. The path I think I like the best is down the side, then down through the seat floors (outboard of the close-out panels), through one seat rib, and under the bag floors to the tail cone.
 
3) anyone dimple the rear seat pans (under the butt of the rear passengers) to use the countersink pull rivets versus the standard pull rivets that will protrude? Was thinking it might be nice to have all flush under there if I pull rear seats for a larger cargo area.
I don't feel like it is worth the extra work. In my case it is covered by carpet and then the seat cushions. If the rear seats are out for extra storage the carpet covers the area.

4) do I need to run my conduit before riveting the rear baggage floor pans? I pan to run the conduit along the side of the aircraft along each side and covered by the side panels that close things out.
That works on the passenger side (right), but on the pilot side, how are you going to get electrical wires past the baggage door? I did not use conduite but rather used the routing concept in Vans optional wire harness OP-37 page 11.
 
2) for those who have put your comm antenna under the rear seats, what did you do for access? If I want to make an access panel that is flus it seems I'd need a 5 year old hand to reach in because the ribs are close forcing the access panel to be tiny. Pics of what you did might be useful here.

I have one under the rear pax seat and one on the tailcone top.
The hatch is tight but serviceable.

87E2C6C0-2A7C-4000-BC39-DDC070448A2C.jpeg

638AF363-49C0-41A0-B71D-CF0C122C6DEA.jpeg

For the conduits, as has been mentioned in other threads, you’ll need more than you think. I have 3 running to the tail one and it’s just enough. Not including the battery fat wires.
I think they should go under the seats. Along the side puts some decent holes through a small space in the baggage bulkhead frame on the RHS.

I prefer a straight-ish run from the rear spar bulkhead to the tailcone. That way, when the conduits fill up and get tight or if you lose or break your pull string (you will) then you can fish with a piano hinge pin.
 
Would anyone care to comment on their thoughts about locating antennas under the rear seats versus under the baggage compartment floor? It seems to me that a belly mounted COM antenna and a transponder antenna would go nicely there.
 
I have one under the rear pax seat and one on the tailcone top.
The hatch is tight but serviceable.

View attachment 20287

View attachment 20288

For the conduits, as has been mentioned in other threads, you’ll need more than you think. I have 3 running to the tail one and it’s just enough. Not including the battery fat wires.
I think they should go under the seats. Along the side puts some decent holes through a small space in the baggage bulkhead frame on the RHS.

I prefer a straight-ish run from the rear spar bulkhead to the tailcone. That way, when the conduits fill up and get tight or if you lose or break your pull string (you will) then you can fish with a piano hinge pin.

You happen to have dimensions you used for the doubler? What are the dimensions of the opening where you stuff your hand down in there?

I was going to have at least 4 runs of conduit. I’ll look at more pictures and advice to see how it’ll best work out for me.
 
I did not like the option to mount the comm antennas under the rear seat or baggage area - for the restricted access as has been discussed.

I mounted them fore and aft under the tunnel, one on each side of the tunnel. The backing plate was joggled to fit over the associate rib so the antenna was a far outboard on each side of the tunnel as possible. This provided adequate clearance to the elevator push tube and such.

The transponder antenna was mounted under the passenger seat, biased to outboard. The ADS-B antenna was mounted aft of the baggage compartment bulkhead, the SkyView ADS-B receiver mounted a few inches from the antenna. The Nav/LOC/GS antenna was in the right wing.

This antenna placement provides for easy access and proved to work well.

Yes - run your conduit before the floors. I have three on each side of the fuselage that then pass under the baggage floor. I ended up using five so now one is a spare.

Carl
 
Both

Both com antennas under the rear seats, outboard.

I made two doublers and covers. Access is incredibly easy, remove the rear seat cushions, lift carpet, Remove cover plate...easy peasy.

Reach through access panel to connect/disconnect antenna BNC.
 
Would anyone care to comment on their thoughts about locating antennas under the rear seats versus under the baggage compartment floor? It seems to me that a belly mounted COM antenna and a transponder antenna would go nicely there.
It is wider there and you can get more spacing between the 2 antennas.

I do have my com antennas under the rear seats and I have access panels. However if I were to build another 10, I would not put in access panels there. What purpose do they serve, what do you need access to? Make sure you have a way to route the coax, or install the coax, install the nut plates and hole in the bottom. Make the hole big enough so the BNC connector fits through. Close it up and later install everything from the bottom. Am I missing something?
 
It is wider there and you can get more spacing between the 2 antennas.

I do have my com antennas under the rear seats and I have access panels. However if I were to build another 10, I would not put in access panels there. What purpose do they serve, what do you need access to? Make sure you have a way to route the coax, or install the coax, install the nut plates and hole in the bottom. Make the hole big enough so the BNC connector fits through. Close it up and later install everything from the bottom. Am I missing something?

No, you aren't missing anything, that would work.

I did find, however, that those access panels came in handy when routing some wiring. Of course, if you know exactly what wires need to be run and where from the start, that is a non issue...
 
It is wider there and you can get more spacing between the 2 antennas.

I do have my com antennas under the rear seats and I have access panels. However if I were to build another 10, I would not put in access panels there. What purpose do they serve, what do you need access to? Make sure you have a way to route the coax, or install the coax, install the nut plates and hole in the bottom. Make the hole big enough so the BNC connector fits through. Close it up and later install everything from the bottom. Am I missing something?

I was under the impression that spacing between COM and transponder antennas didn't matter so much, unlike spacing between like antennas. For COMs, I'm installing a bent whip on the belly and a whip on the dorsal area, so there's no issue with separation there.

Am I wrong about a lack of concern for spacing between COM and XPDR antennas? I have at least 30" of space between potential antenna locations on the bottom under the baggage floor.

My thought about installing the COM further back on the belly was to avoid shadowing by the landing gear as much as possible, although that may not be a big concern for an RV.
 
It is wider there and you can get more spacing between the 2 antennas.

I do have my com antennas under the rear seats and I have access panels. However if I were to build another 10, I would not put in access panels there. What purpose do they serve, what do you need access to? Make sure you have a way to route the coax, or install the coax, install the nut plates and hole in the bottom. Make the hole big enough so the BNC connector fits through. Close it up and later install everything from the bottom. Am I missing something?

X2 I can access the connector and pull antenna from the bottom. I think though it depends on your antenna. Mine uses nut plates on the inside to install.

Keith
 
X2 I can access the connector and pull antenna from the bottom. I think though it depends on your antenna. Mine uses nut plates on the inside to install.

Keith


I'm using the DeltaPop antennas, which attach via studs with nuts inside the aircraft, so I will need access to them from above to remove/service them.
 
Antenna spacing

I am admittedly "electronically challenged" but my Garmin Xponder and Garmin Radio DID have a recommended minimum distance between antennas. I had some interference (according to my radio guy) and ended up moving one antenna which solved the issue. At the risk of being Captain Obvious, I would certainly research and respect this separation if applicable.
 
belly antennas

I mounted belly antennas for ADS-B and XPDR under the front seats. Com antenna on inspection plate in wing bay, and another embedded in the cabin top. Access is not a problem.
 

Attachments

  • IMG_2182.jpg
    IMG_2182.jpg
    280 KB · Views: 151
  • IMG_2177.jpg
    IMG_2177.jpg
    296.8 KB · Views: 167
I've posted these here before, but I neglected to mention the VOR vee dipole is in the cabin top along with com 2 antenna at the right rear passenger's shoulder. These are made from copper foil tape. GPS pucks are in the overhead console but inside the cabin top. ELT antenna is under the empennage fairing. Net result is no protruding antennas on the top or fuselage, just the two blade antennas on the belly and the bent whip com 1 under the wing. No idea of the speed increase from this effort, but confident it's not zero.
 

Attachments

  • IMG_4762.jpg
    IMG_4762.jpg
    293 KB · Views: 194
  • IMG_4765.jpg
    IMG_4765.jpg
    306.9 KB · Views: 191
  • IMG_4766.jpg
    IMG_4766.jpg
    274.9 KB · Views: 147
  • IMG_4810.jpg
    IMG_4810.jpg
    274.7 KB · Views: 193
Baggage floor access

I drilled the holes for access to the step bolts, per the builder's manual, but still needed access for the two antennas that I plan to install under the baggage floor. I bought the upper fuse access panels, thinking I could use them in the floor, but they were too large.

Instead, I installed two VA-195C access hatch doublers and two VA-195D access hatches for the wing - see p.19-2 of the builder's manual. I installed a third one to clean up a homemade access hatch a previous builder had cut into the floor, too. Great access.
 

Attachments

  • Access hatch placement.jpeg
    Access hatch placement.jpeg
    50 KB · Views: 151
  • Access hatch WIP.jpeg
    Access hatch WIP.jpeg
    83.7 KB · Views: 182
  • Access hatches.jpeg
    Access hatches.jpeg
    57 KB · Views: 166
Baggage floor conduit

After studying what other people had done, I decided on four conduits - two on each side of the tunnel. Even though I don't know what capacity I'll need, I haven't heard anyone complain about having too much room for wiring.

I decided to go with Carlon ENT conduit. It's light and flexible, but will also hold the slight bends needed to pass through the lightening holes. Carlon makes push-on terminations with screw-on caps that work nicely to hold the conduit in the forward holes. I found almost everything I needed at Menard's - a DIY home center in the Midwest. I also picked up a couple of fittings at McMaster-Carr, which fortunately is about two miles from my house.

I discovered that 1" ID conduit wouldn't go under the step tube, so I used 3/4" ID for the two outboard conduits and 1" ID for the two inboard conduits. You can see the clearance below the step tube in the second photo below, where I simulated the step tube with 1" conduit.

I didn't want them bouncing around under the baggage floor, so I cemented tie-wrap anchors to the skin with E-6000.

Under the rear seats, I used Adel clamps, aluminum standoffs that I found in the aviation drawers at Ace Hardware, #AN3 bolts, and Nord-Loc washers under AN365 nuts. I really don't want them coming loose under the riveted seat pans.

When I asked Vans about running conduit, they cautioned not to drill through the rear spar (F-1005B). That's why I installed them near the top of the rear spar bulkhead (F-1005A).
 

Attachments

  • Conduit installation.jpeg
    Conduit installation.jpeg
    98.4 KB · Views: 233
  • Conduit clearing step tube.jpeg
    Conduit clearing step tube.jpeg
    70 KB · Views: 175
  • Conduit standoff.jpeg
    Conduit standoff.jpeg
    68.9 KB · Views: 221
You happen to have dimensions you used for the doubler? What are the dimensions of the opening where you stuff your hand down in there?

I was going to have at least 4 runs of conduit. I’ll look at more pictures and advice to see how it’ll best work out for me.

The opening is 1 7/8 x 3.5” the doubler is about 3/4 all around.
 
Antenna placement near battery- OK or not

Hello

I am just about to drill for my antennas. I was planning on Com-2 just above the rear battery on the top of the tailcone and Com-1 just on the side of the battery on the bottom/belly. Both are DeltaPop. Top one is strait, bottom is bent.

My reasoning is I can get to them easily with the baggage bulkhead off. Any known issues with them being just behind the baggage bulkhead (keeping it far enough back to avoid any fiberglass transition from cabin top to metal and still have a good ground plane?

Any issues with "noise" close to the battery? I am using good quality connectors and RG-400.

FYI-
Transponder antenna to GTX45 in the tunnel, forward of the baggage bulkhead and aft of the flap motor. About 45 inches forward of Com-1 antenna on the belly by the battery

Nav antenna on top of the VS- Already mounted. Drilling the cat's whiskers at a 45 degree angle was a challenge yet came out really well.

Qty 1 to 3 GPS antennas on glare-shield or aft of the Com-2 antenna on the tail-cone to achieve a good ground plane and out of the laminar flow area. Separating them enough to avoid the common failure mode.

I put fireproofing on th belly by the firewall and cannot mount any antenna in that section.

Thanks
 
Would anyone care to comment on their thoughts about locating antennas under the rear seats versus under the baggage compartment floor? It seems to me that a belly mounted COM antenna and a transponder antenna would go nicely there.

I have two comm antennas under the rear seats. I did put access panels on the rear seats, in ten years, I’ve never had an issue with both commas being on the bottom.

I would keep the transponder antenna away from the comm antennas. Mine is located just forward of the fuel pump in the tunnel

I also have an ADSB and APRS antennas mounted aft off the baggage bulkhead.

I have a NAV antenna just forward of the rear tie down.
 
Back
Top