Chapter 21 – Strakes & Fuel Tanks

Chapter 21 – Strakes & Fuel System

May 2012 — After a back & forth discussion with a builder that decided he wasn’t going to use these caps anymore, I bought these Newton fuel caps on Ebay.

These are the locking style caps as you can see in the pic below.

I was looking for the Newton A36LFF style caps with the solid flange vs. the flange that has bolt holes around the perimeter for attachment.  I believe these are slightly different than the A36LFF in that the flanges on these are simply sans holes, while if I’m correct the actual A36LFF has a raised lip around the cap and a slightly lower flange to allow it to be glassed in place.

Below is a shot of the interior side of the fuel cap.

And a shot of the retaining flange, underside.

I definitely remember for the price that I would make this configuration work since the pair of these caps were way less than buying just one A36LFF cap from ACS!  Plus, the flange showing on the external fuel tank surface versus just the cap peeking out is much more visually appealing to me.  I understand the issues of securing it, and I have an idea or two that will keep these guys in place.

One cap does have a couple of very light scratches (which I believe will happen over time anyway) and I’ll make a point that while these have a goldish appearance in all these pics (from the original seller) they in fact have the normal fuel cap silver aluminum finish.

[Admin Note:  I got a note from fellow Long-EZ builder Brian Ashton from Alaska asking a question about my fuel caps that I mentioned in my April 2015 post on acquiring fuel cap keys from ACS for these caps.  Well, to answer Brian’s question I had to go back and do a bit of research on my own fuel caps.  Turns out, I was remiss in ever actually posting anything about my fuel caps, so I am doing that here to correct my oversight!  Thanks Brian!]

•••

3 October 2012 — Below is the EFII Electric Fuel Boost Pump with filters that I recently received from ACS.

Chap 21 - Fuel System

•••

18 October 2012 — I thought I would show a picture of the fuel blisters that I just recently received from Feather Light.  I’ll be real happy when I’m posting pictures of these guys installed!

Chap 21 - Fuel Blisters

[Operational Note: I did NOT end up using the fuel sump blisters above.  Since I have the Mike Melvill Carbon Fiber cowlings that incorporate the Berkut-style “armpit” cooling intakes, I did not want these fuel sump blisters mounted immediately in front of the intakes and causing significant disruption to my engine cooling air.  I instead mounted the sumps in the GIB thigh support (see ‘Internal GIB thigh support fuel sump tanks’ page).]

•••

16 May 2013 — I researched & ordered my AN fuel line fittings.

•••

21 May 2013 — Although my primary focus today was to get both Inboard sides of the NG30s glassed, I like to multitask whenever possible.  In the pics below I’m sure you’ll note the Rock Star energy drink can covered with duct tape.  I glassed it with a 2-ply BID layup immediately following the NG30 layups, and then of course peel plied it.

Chap 13 - Glassing NG30 plates

This can is the start to the makings of a fuel tank vent manifold as James Redmon did on his fantastic Berkut 13.  James has an awesome site covering his Berkut build at www.berkut13.com, and for details on the fuel tank vent manifold system click here.  Below are also some before and after closeup shots of the can as it was glassed/peel plied.

Chap 21 - Fuel Vent Manifold

Chap 13 - Glassing NG30 & Fuel Vent Manifold

Chap 13 - NG30s/Manifold glassed/peel plied

Chap 21 - Fuel Vent Manifold

Since I laid up the fuel tank vent manifold 2-ply BID layup with fast hardener, just a couple hours later I pulled the peel ply.

[Operational Note: Unfortunately I will NOT be using this fuel vent manifold since I will be using a left & right sumped system (as per plans, minus the internal sumps) and NOT a no-management fuel system.  I will thus have 2 vents per tank that exit each tank, travel along the top edge of the firewall and then exit out the bottom of the aircraft on each side near the bottom of each strake.]

•••

22 May 2013 — I removed the can from the fuel tank vent manifold body.

Chap 21 - Fuel Tank Vent ManifoldChap 21 - Fuel Tank Vent Manifold

•••

27 May 2013 — I started off by marking & cutting the ragged ends off the fuel tank vent manifold body (that I glassed around a Rock Star energy drink can).

Chap 21 - Fuel vent manifold bodyChap 21 - Fuel tank vent manifoldChap 21 - Fuel tank vent manifold

I then used one of the cut end pieces to make a form for the fuel vent manifold end cap using blue wing foam.

Chap 21 - Fuel tank vent manifold capChap 21 - Fuel tank vent manifold cap

After I formed the shape I was looking for, I covered the entire form with duct tape & then fastened it using the tape to a duct tape base on a piece of cardboard.

Chap 21 - Fuel tank vent manifold cap

The pics below show the form ready for the 2-ply BID layup.

Chap 21 - Fuel tank vent manifold cap

Chap 21 - Fuel tank vent manifold cap

And here’s the cap curing in front of the heater (it was quite chilly weather in Germany even though it was late May).

Chap 21 - Fuel tank vent manifold capChap 13 & Chap 21 pieces curing

Since I used all fast hardener on these components, I think the much faster curing sealed the glassed pieces to the foam more than usual.  The first fuel tank vent manifold cap I made was a bear to get off the form, and I ended up tearing up the somewhat fragile foam form to get it off the darn thing.  Thus, I had to make a completely new form for the second fuel tank vent manifold cap.  No worries.  Also, when I was glassing the 2-ply BID layup, some of the plies separated at the “corner” of the cap.  Instead of messing around with pulling the separated ply, I simply added another ply of BID for 3-plies total on the second cap.

Chap 21 - Fuel tank vent manifold cap

After I got the second fuel tank vent manifold cap laid up & curing, I then mocked up the first cap to see how it fit.  Once I saw that the fit was good I drilled a ~21/64″ hole (I had to use my Perma-Grit tool once I drilled the initial hole so the measurement is an approximate…forgive me Marco for not pulling out the calipers!) and mocked up the AN912 bushing & Nylaseal adapter.

Chap 21 - Fuel tank vent manifoldChap 21 - Fuel tank vent manifold

Once I confirmed that AN bushing fit well, I sanded/prepped around the hole on the cap and floxed the bushing into place.

[Operational Note: Unfortunately I will NOT be using this fuel vent manifold since I will be using a left & right sumped system (as per plans, minus the internal sumps) and NOT a no-management fuel system.  I will thus have 2 vents per tank that exit each tank, travel along the top edge of the firewall and then exit out the bottom of the aircraft on each side near the bottom of each strake.]

•••

28 May 2013 — I pulled the fuel tank vent manifold end cap from its form, cut off the excess material & then sanded it. Below are the pics showing the manifold in its first ever appearance as one component.

Chap 21 - Fuel Tank Vent ManifoldChap 21 - Fuel Tank Vent Manifold

•••

5 June 2013 —  First off, the pic below shows my Andair fuel valve.

RAM/Pitch Trim Mount & Fuel Valve

On the fuel tank vent manifold I drilled a hole in the top (again, about 21/64″ in diameter) of the second cap & then test fitted the AN912 bushing.

Chap 21 - Fuel tank vent manifold capChap 21 - Fuel tank vent manifold capChap 21 - Fuel tank vent manifold cap

I then marked the first 2 (out of 4) side positions & drilled those holes as well.

Chap 21 - Fuel tank vent manifold

I then test fitted the two AN912 bushings into the side of the manifold, placed the new end cap in place and prepped all of the bushings & glass for floxing.

Chap 21 - Fuel tank vent manifold

I floxed in 2 AN912 bushings into the side of the manifold & floxed one AN912 bushing into the cap.  I set them in front of the heater to cure.

Chap 21 - Fuel tank vent manifold

•••

6 June 2013 — I mocked up my Chapter 21 – Fuel Tank Vent Manifold parts and still have 2 more side bushings yet to install.

Chap 21 - Fuel Tank Vent ManifoldChap 21 - Fuel Tank Vent ManifoldChap 21 - Fuel Tank Vent Manifold

•••

8 June 2013 — I used the remaining amount of epoxy from the winglet layups to mix up a batch of flox to install the the final 2 each AN912 bushings into my fuel vent manifold body. After I floxed them in, I set the manifold body in front of the heater to cure (the heater it’s leaning against is obviously not the heater being used).

Chap 21 - Fuel Vent Manifold

•••

12 June 2013 — When I mixed up the flox for the installing the Davenport leaf spring attach tube, I made up enough to also flox one of the Fuel Vent Manifold end caps into place.  I prepped the glass surfaces to be bonded by sanding the external top of the manifold body & the inside edge of the cap.  Below is the Fuel Vent Manifold end cap being floxed permanently to the cylindrical manifold body (I’ll blame the blurry pics on my camera being tempermental).

Chap 21 - Floxing on fuel vent end capChap 21 - Fuel vent end cap floxed

[Operational Note: Unfortunately I will NOT be using this fuel vent manifold since I will be using a left & right sumped system (as per plans, minus the internal sumps) and NOT a no-management fuel system.  I will thus have 2 vents per tank that exit each tank, travel along the top edge of the firewall and then exit out the bottom of the aircraft on each side near the bottom of each strake.]

•••

11 January 2014 — Well, as I was trying to nail down some particulars & plan out how I was going to build my strakes, I went to Nate Mullins’ wonderful Long-EZ build site.  Now, before I get too far into this, you have to know that my catch snarky phrase of late–well, over the last couple of weeks–has simply been: “Sometimes it’s better to be lucky than good.”  Ok, I was going through Nate’s strake-building adventures chronicled on his MyKitLog build site, when ironically, or maybe I should say coincidentally . . . oh, what the hey, we’ll call it serendipitously, I ran across the part where he stated that when he acquired his Long-EZ project, that it came with both the Aerocad/Aerocanard strake kit, and the Featherlite Strake Leading Edge Kit.  Thus, he had to make a choice between the kits when he built his strakes, so he went with the Aerocad kit.

Now, I have bugged Mike & Larry at Feather Lite every few months, since I started building my Long-EZ in April 2011, to see if they had started making the Foam Strake Leading Edge Kits.  I’ve talked to a fair number of builders, the Old Guard, etc. to know that the strake’s leading edge can really detract from a canard/ez’s look if not done well.  I really liked the idea of capping the entire leading edge vs. building the plans method, joining the strake tops & bottoms to LE as far back & away from the leading edge as practical (in the straight, not curved, area), and having a wet leading to add to the fuel amount in the strake. Unfortunately, in late 2012 Mike & Larry had had enough.  Apparently they felt I was by then a mature enough builder that they could break the bad news to me: they had no plans of ever making the strake leading edges again (they can’t because the foam manufacturer changed the actual chemical properties of the foam… and now it can’t contour properly to the forms).

So, when I read Nate’s strake building account, I asked myself in disbelief, “Could it be?!” Well, a quick email to Nate asking if he still had the Featherlite Strake Leading Edges and would he be willing to sell them to me, fortunately came back with a resounding yes! Eureka! (Well, actually Featherlite! But hey, they’re all good guys!)

A little bit of coordination later, and a ensuing rendezvous between Nate and my ‘ol northern Virginia neighbor Richard (who now lives in Kentucky an hour or so from Nate in Tennessee) and I was the new proud owner of a “new” set of Featherlite Strake leading edges. I would say I’m the happiest guy in the world, but I think that would actually be Larry Lombard from Featherlite ‘cuz that crazy yahoo will stop calling & bugging him about those damn strake leading edges.  In addition, I’ve been able to banter about a bunch of different build ideas with my new Long-EZ buildin’ buddy Nate!

And here they are:

Chap 21 - Featherlite Strake LE Kit

Since Richard still visits the northern Virginia area often, he’ll be bringing up the kit in May. BTW, I was teasing Richard that there must be some cosmic connection between him and Featherlite, because he was the one who drove me to the cargo terminal in his truck to pick up my crates of Featherlite foam cores to ship them off to Germany.

•••

3 May 2014 — This afternoon I was able to get a hold of Master Canardian Nick Ugolini and order a set of his Capacitance Fuel Probes.  Nick designed the probes himself to be used in canards and to link up to Princeton Fuel Probe electronics to provide high quality fuel reporting to EFISs, etc.

Chap 21 - Capacitance Fuel Probes

At first I resisted the idea of fuel probes since I already have Vance Atkinson’s fuel site gauges and will be using a fuel flow sensor, but considering that these are just a few ounces a piece including the electronic control boxes, I figured knowing my exact fuel quantity for a total weight penalty of well under a pound was worth it.  I had just read too many reports of high praise for this system to ignore it all and not pull the trigger on a set. (I pulled the pics below off of Nick’s blog):

Chap 21 - Capacitance Fuel ProbesChap 21 - Capacitance Fuel Probes

Another motivating factor for installing these early on (i.e. during the build) is that since I’m gearing up in the planning and R&D of building my strakes, it’s just that they’re a heck of a lot easier to install now during the initial strake build than afterwards.  Now, that being said, they actually don’t look that difficult to install after the strakes are built, but anything I can do to avoid introducing potential contamination–in the way of bits & chunks of foam & glass, etc–into the fuel system is worth doing early on.

•••

7 April 2015 —  Today I got some important keys.  One set, the cam lock & keys, is a recent requirement and is for the headrest opening, while the other has been on my list to acquire since 2012, which are the keys for the Newton fuel caps that I bought back then.

The two sets of keys on the right are the keys to the Newton fuel caps.  At this time, these are a special order item if you want to purchase them through Aircraft Spruce.

Headrest lock & gas cap keys

•••

30 September 2015 — After getting settled back in from being at Rough River this past weekend, I set about to do a proper inventory of all the strake ribs and fuel tank baffles from the Feather Light Strake Leading Edge Kit that I bought off Nate Mullins back in late 2013 and finally just picked up.

Here’s a shot of them below back AT MY HOUSE! The pieces all have a shiny covering on them which is just an extra layer over the peel ply.  All the parts will need a final trim before final installation, but having these parts pre-glassed and pre-cut should save me days on the strake build.

Feather Light Strake Kit

I cleaned up the inside glass of the leading edge pieces, and then set up for a pic before the were once again stored away.

Feather Light Strake Leading Edges

•••

29 June 2016 — I finally knocked another item off my list by giving the folks at EFII a call to order a couple of 90° fittings. Unlike standard right angle fittings, these 90° fittings supplied by EFII can be clocked into any orientation so the exact angle of the connected fuel lines can be dialed in.

Fuel pump

I need these right-angle fittings since I’ll be placing the fuel pump in the hell hole mounted on the underside of the CS spar. The awesome folks at EFII quickly sent me out a pair of the 90° fittings with the only requirement that I send back the stock straight fittings.

Fuel pump

Here’s my newly configured fuel pump, now ready for install!

Fuel pump

•••

8 September 2016 — Today I started off by calling the folks at EFII to query them on my options for mounting my EFII fuel pump.  In my research on fuel pumps, the position of the pump in relation to the fuel IN feed line is important, with a general requirement that the fuel pump be situated at a lower point than the IN fuel feed.  Since I was thinking about mounting the fuel pump directly to the bottom of the CS Spar in the hell hole, I wanted to make sure I could do this without violating any conventional wisdom mandates.  Well, as it turns out –and this is directly from the EFII horse’s mouth– it doesn’t matter the elevation of the pump vs the feed line, as long the pump is mounted horizontally.  Still, after taking the pump down to the shop and mocking it up in a few locations, I decided the hell hole was going to be a crowded place, both in components making their residence there and with all the transient elements (fuel lines, cable antennas, wiring, cables, etc.) coming and going, let alone the exact space required for my RAM air intake. So I decided to kick this fuel pump can down the road and wait until I get closer to HAVING to install it.

•••

26 October 2016 — I started off today with something I was curious about, and wanted to answer a nagging question that I’ve been having: will the EFII fuel pump fit under the pilot seat thigh support?  In line with what I posted above, I’ve seen a number of builders place the fuel pump up front near the fuel valve.  This is good for a few different reasons: 1) ease of maintenance, 2) direct knowledge –due to the noise/vibration– of whether its on or off, and arguably the most important reason, 3) is it drives 2-1/2 lbs of weight farther forward in the fuselage.

So, since I wanted to see where a good location was for the fuel pump, and in relation to the fuel valve, I played around with a few different mounting locations.  I stopped at this one since I really like that the pump can be mounted vertically here, thus driving as much of the pump weight forward as practically possible.   It also gives some nice space for the fuel valve and the fuel lines.

Fuel pump & valve mockup

•••

11 May 2017 — Today I started out doing some planning and inventorying for my fuel system.  Since I’m going to make my new work demarcation line at the pilot’s seat bulkhead, going forward, then I needed to figure out my fuel system in real terms, not just in my head.  I drew out the fuel system on a white board and then did an inventory to see what I had on hand and to see what I needed to order.  I was fairly pleased that I had the majority of stuff I needed on hand, but will need to order about $35 in fittings from ACS.

I also did some research on the exact installation requirements for each fuel system component.  For example, on the Andair fuel valve I could clearly see that the big red selector handle needed to come off to install it, but I hadn’t even truly read the install manual until today to find out how to remove the handle, and install the unit.  I also had some questions on the FT-60 Red Cube fuel flow sensor that I eventually got answered on the VAF site.  In addition, I wanted to double check some info on the fuel pump.

After a few hours I was happy with my progress on the fuel system and was satisfied that I actually knew the direction I was headed with that system once again.

•••

12 May 2017 — Today I focused on mounting the EFII fuel pump and its pre-filter.  I played around with the configuration for a bit before finally narrowing both components’ locations as shown below.

With the existing fillet at the bottom aft of the instrument panel –where it’s glassed to the fuselage floor pan– I needed to have a slight gap between the fuel body and the instrument panel.  I thought 1/16″ (0.063″) would do it at first, but it wasn’t enough and still caused the bottom of the fuel pump to kick out aft a little bit, not allowing for a true vertical install.  I tried 1/8″ (0.125″) but it seemed a bit too much.  I then scrounged up some 0.093″ scrap aluminum to test as a spacer and that did the trick.

With the position of fuel pump dialed into its final position, I clamped it and drilled the top 2 mounting holes into the lower instrument panel.

I then made up 2 K1000-3 nutplate assemblies with 1/16″ phenolic.

With my fuel pump positioned, I then fiddled around with the pre-filter before I finally figured out its final position.  I then marked the spot and 5-min glued a click bond in position (after I prepped the clickbond).

I then laid up 3-plies of BID over the Clickbond after creating a flox transition around its edges.

I also floxed in the left nutplate assembly and screwed an AN3 bolt into it to hold tightly in place while it cured.  Over on the right side, due to the drilled mounting hole being so low on the lower instrument panel cross frame (top edge of map box/lower edge of leg opening) I micro’d in a half moon looking piece of H45 foam in prep for 2 plies of BID on the front side, and 1 on the aft side.

If you’re wondering about the bolt head’s close proximity to the fuel pump frame, and how it can’t possibly turn, you’ve spotted an issue.  Tomorrow I need to pick up some hex head socket cap screws to allow them to turn in tight quarters.

I then decided it was time to roll up my sleeves and knock out the hour++ trial and error process of forming respective Devinycell wedges for both the right and left side of the fuel pump.  As you can see, these foam pieces will make up the mounting pads for the fuel pump frame’s “feet,” allowing me to bolt in the fuel pump frame on the lower aft sides (vertical bolts) and the forward side (left & right as well) using horizontal bolts.

After mocking up the fuel pump countless times, with a myriad of sanding with my Perma-Grit tools (still love those things!) to shape the respective pads, I finally got the shape and positioning I wanted with the pads.  Moreover, with the pads in place and the fuel pump temporarily installed, I could checked that there was a decent gap for the eventual mounting of the bigger sized click bonds for the aft side fuel pump mounting.

I then micro’d the foam pads in place and laid up 2 plies of BID over each pad.  Down in the lower left corner in the pic below is a small square ply of BID that I glassed in placed and peel plied (along with the pad layups) to patch a small divot I had put in the floor at some point… I still had a small amount of epoxy left over allowing me to do this.

I also floxed the right mounting nut plate assembly into place (after I redrilled the hole) and held it in place with an AN3 bolt while it cured.

Below you can see a shot of the small curved piece of foam I glassed in place to help as a backer for the the right side fuel pumping mounting nutplate  assembly.

With that, I did one final check on all the layups, and called it a night.

•••

13 May 2017 — First thing this morning I pulled the peel ply off the fuel pump mounting pads.  There were a couple minor air bubbles but the layups looked good.  I cleaned up the peel ply strings a little before snapping this shot.

And then sanded the areas that I couldn’t easily apply peel ply to last night.

I then quickly checked the fuel pump fit on the mounting pads.

I then prepped & floxed the 2 larger click bonds in place onto the mounting pads, securing the fuel pump in its mounting position to keep the click bonds appropriately spaced.

I ran over to visit my EAA buddy when I also stopped by my local Village Hardware store to pick up some 1-1/4″ SS hex drive cap head screws.  Normally stores only have half-inch increments available after 1″ (then 1-1/2″, 2″, 2-1/2″, etc.) but behind all the other cap head screws they had a small box: 1-1/4″ length for apparently a previous special order!  Voila!  And they didn’t even have a price… but we worked out a price and I bought a couple and was on my way to Jeff’s in short order.

Upon returning from Jeff’s a few hours later,  I then cleaned up & prepped the 2 large fuel pump mounting click bonds for glass.

After adding a bit of flox for transition around the edge of each click bond, I then laid up 3 plies of BID over each one.  I peel plied the 2 layups and then took off to meet a buddy of mine for dinner and a movie (sorry, no pic of the peel ply on the layups).

Upon returning home for the evening I pulled the peel ply and cleaned up the layups.

I then test fitted the fuel pump mounting on the freshly installed lower click bonds on my glassed foam mounting pads.  Looking good!  One small issue that I have is that the 1-1/4″ bolts are too long to fit in the gap on the fuel pump mounting frame.  I’ll have to drill out the aft-side mounting holes –which aren’t used here– to a wider diameter to allow the bolt head to fit and slide through to the other (forward) side.

I then test mounted the fuel pump’s pre-filter to check its fit & placement.  Again, looking good so far!

•••

14 May 2017 — Tonight I started out by drilling out the front side mounting holes on the fuel pump to 5/16″ diameter to allow me to slide the hex head cap screw through the front to then hold the fuel pump in place.

After drilling the front side of the fuel pump frame for the 2 top side mounting screws, I mounted the fuel pump . . . officially for the first time!

Here’s a close up of the hex head cap screw/bolt securing the top of the fuel pump in place.  As you can see, I still need to micro & glass the nutplate assemblies into place.

Here’s a shot of the aft left side mounting hole that I drilled out to 5/16″ & tapered with a large 3/4″ countersunk bit for ease of getting the mounting bolt inserted.

I wanted to ensure that all the pieces of my fuel hobby project here would fit together, so I cut a 3″ piece of 3/8″ 3003-0 aluminum fuel line tubing and collected up some fittings to connect the fuel pre-filter OUT to the fuel pump IN line.

With such a small piece space in the flaring & bending tools were TIGHT, but as you can see I was able to get the flares made & tubing bent to connect the pre-filter to the fuel pump.

Here’s another shot after I rotated the tubing downward about another 1/2″.

Also tonight I wanted to get one more major task completed tonight: run the fuel line from the Andair fuel valve OUT port to the EFII fuel pump pre-filter IN port.

In reality, this task was a 2 part process.  I ended up nearly destroying the first piece of tubing I tried to install here, but then ended up using it as a prototype model to then craft the second tubing with the tubing bender vs. my ham-fisted manipulations of the tubing.  I figure this will the be the most difficult fuel line tubing connection that I’ll have to make on my fuel system.

Beside just getting this tubing piece configured and in place, my actual main goal here was to figure out the positioning of the Andair fuel valve.  As per my norm, you’d probably not be surprised to learn that I am NOT putting this valve in the plans position!  Close, but it will sit over an inch higher and well aft of the plans position.

Why?  Well, in talking to current Long-EZ flyers, and having sat in Marco’s Long-EZ, I can tell you with all certainty that I want to have the ability to SEE what position my fuel selector is set on versus only being able to FEEL the position of my fuel selector valve.  I will of course check this out and ensure I have enough seating room, but beyond any other issues, this is my main goal as far as the fuel valve configuration & installation is concerned.

•••

15 May 2017 — Today, with the leftover epoxy I had from glassing over the pitch trim mount, I added a little more to the bit of flocro I had and made primarily a micro mix.  I spread the micro on both the left & right side nutplate assemblies used to secure the upper fuel pump attach bolts in place.  I then laid up 1 ply of scrap BID over each of the nutplate assemblies and peel plied the BID.

Then, while the composite stuff cured, I set my sights back onto the Andair fuel selector valve. I took the valve lever and cover off to assess how it will get mounted to the fuel valve bracket & cover.  I also wanted to double-check that the K1000-3 nutplate mounting holes were countersunk for the rivets, which they were.

I then riveted 3 each K1000-3 nutplates to the Andair fuel selector valve.

I set the fuel selector valve back in place and will assess it more fully later on.

Here are both the left & right side nutplate assemblies used to secure the upper fuel pump attach bolts after their layups cured.  I realize it looks like a lot of micro is covering these nutplate assemblies, but there really isn’t that much.   The thickness of the phenolic combined with the back side of the nutplate, rivets, etc. makes it look like there’s a ton more micro than there really is.  Admittedly, there is a bit more micro on the right side nutplate than the left.

•••

16 May 2017 — Today turned into an all day planning, coordinating and all around down a dozen different rabbit holes day.

I’ve been having a back & forth email discussion with my buddy Dave Berenholtz on, well, just about everything involved in the build, but today specifically was on the sump tanks and the fuel system.  I haven’t really communicated my fuel system since I have been researching, studying, and planning it for literally 4-5 years now.

Thus, today was the day to polish off the particulars on my fuel system and get it finalized so I can implement it.  To understand my fuel system planning, I will be throwing out some big names in the canard world…. not to name drop, but to show the pedigree (not mine) and experience of those involved in this discussion.

It started a number of years ago as I was talking to Marco on the phone and sent him a link to Wayne Blackler’s Long-EZ to make a point as to what I was on about.  After a few minutes he simply declared over the phone: “He has no external sumps.”  He noted something I had failed to notice, and we pondered over that a bit.  I bit later I discussed with Wayne his “no-management” fuel system, as I did with Ken Miller, Bill James, and Vance Atkinson, among others.  So, although I started out ready to install the plans version fuel system, I made a distinct departure from that plan and decided on a GIB thigh-mounted central sump with no fuel selector valve system.  I was going no-management all the way Baby!

Well, my planning was geared towards the no-management fuel system for years when last year before RR I made one final search online before installing my EFII fuel pump right below the CS spar…. and I mean it was going literally on the bottom surface of the CS spar, centerline.  I have to say I had a nagging feeling about putting all that weight back there (it’s 2.5 lbs), and when I saw a pic of Joe Carragio and few others who had mounted there fuel pump under the pilot thigh support, it got the gears in my brain turning. Hmmm…

I did a quick mockup of the fuel pump up in the pilot thigh support area and realized it would fit perfectly.  Hmmm….  Ok, well a big reason that I was going with the no fuel management system was the integral GIB thigh support sump, meaning: no external sumps.  Why is that important to me?  Simple. I have the Berkut-style armpit engine cooling intakes on my cowlings.  These sit literally inches behind the plan’s external fuel sumps.  This means not only accepting more drag in general, but bringing disrupted, disturbed, burbling air into my engine for cooling.  Not optimal.  The no management thing, well, that would be nice.  Of course, that came with a decent, unique risk all its own. But added drag and disrupted engine cooling air! Well, I was not willing to accept that when I could simply move the fuel from an inch away from the GIB to an inch away from the GIB (IMO!)

Fast foreward.  After pondering it for a number of months, looking at the pros & cons, I decided to do what “we” in Washington, D.C. are best at: COMPROMISE!  I decided to go GIB thigh support sumps (yes, plural) by simply not making the mouse holes that would normally be made in the center rib of a single tank sump.  I then would use the Andair fuel valve I bought many moons ago –since I was adding fuel weight going forward anyway. Moreover, since I needed a fuel line going to the pump, and a return coming back, what was the complexity or weight of one more?

The bottom line is I will be going with a hybrid fuel system.  No external sumps with internal fuel sumps under the GIB thigh support (yes, I know the arguments of “bringing fuel into the cockpit” . . . and clearly I’ve weighed all my pros & cons, and risks & benefits). I will however keep the separate tank concept by running the fuel through the Andair L-R-OFF fuel selector valve.

Today I confirmed installation requirements with EFII for my fuel boost pump and Precision Airmotive for my Silver Hawk EX fuel injection system.  After getting questions answered regarding size and location of filters, and fuel pressure sensor connection info, I finalized –after 7 years– my fuel system!

Now, to throw yet another wench in the works, I’m strongly considering knocking out my internal fuel sump in the back seat, which would then allow me to ACTUALLY run my fuel lines for the left & right sump feeds to the fuel valve.  In addition, that would clearly give me the info on spacing requirements I need for fuel lines, wiring, etc. going down the right sidewall.  This would also give me all the real world clearance specs I need for the pilot thigh support ribs and configuration, under armrest configuration for the right side, etc.

I will sleep on it, but I am strongly leaning in that direction as my next move.

Also today, besides updating my fuel system diagram (last updated June 2014) and my firewall components & wiring placement & configuration diagram (last updated Feb 2014), I also updated the fuel system wiring diagram and the engine information/management system wiring diagram.  That may not seem like much, but the phone calls and digging into the manuals and websites to confirm, verify and update components, do analysis on part selection, prices, check inventory, etc. . . .  well, that all consumed about 6 straight hours.

I then spent a good hour sitting in the back seat, marking up my thigh support requirements, and then trying to guesstimate how to translate that over for the passengers I’ll be carrying.  As a comparison, the thigh support mod spelled out in CP 28 has the front wall at 37″ forward of the firewall, 4.5″ high, and then tapering back 6″.  Before climbing into the back seat I looked at Dave B’s sump tank, which is a little too robust for me (in all fairness, he called that), and Bill James’, all online of course.  I then looked at the Berkut GIB thigh support sump plans, reread emails from the whole gang I mentioned above, and then after a few machinations dialed mine in at 35.5″ forward of the firewall, with a height of 6.2″ and tapering back around 10″.  I’ll continue to work out the particular specs over the next day or two, and then make my decision on whether to break ground on this part of the build or not.

•••

17 May 2017 — Today I did over an hour’s research on fuel system related topics.  I then went down to the shop and decided to knock out all the 1/4″ 2024 aluminum hard points for both the main fuel tank fuel drain valves that exit the front of the strakes and the sump tank fuel drain valves.

I marked up my 4″ wide (convenient eh?!) piece of 2024 into 1″ squares.  Then, knowing my Sharpie lines would be gone in 3 seconds after I started, I scribed the lines. I then center punched the crosshair for each hole for a nice starting point for my drilling.

I then drilled subsequently larger holes . . .

Until I finished drilling the holes out for the final diameter required for a 1/8″ NPT Tap: 11/32″.

I then started tapping all the holes in old skool fashion with the tap and a crescent wrench — and of course some cutting fluid.

Yes, I really wish I had a nice tap handle for larger taps, like the one I have for smaller taps because each one of these holes took at least 15 minutes.  Below is a shot of the first hole finished.

 

After a good bit I finished tapping all the holes with the 1/8″ NPT tap.  I then cleaned up the 2024 aluminum piece in order to test mount all the drain valves.

I then rounded up the pair of main fuel tank drain valves that exit the front of the strakes.

I then mounted all the fuel drain valves that will be on my Long-EZ.

Here’s a profile view of all the fuel drain valves.

And, lastly, an “inside the tank” view of all the fuel drain valves.

Finally, today I dropped a small order with ACS for the remaining required fuel system fittings from the firewall forward.

•••

18 May 2017 — I started off today by marking up the aluminum to cut out the individual hard point blocks for the fuel drain valves.

I had an issue that the only saber saw blade for cutting aluminum that I had on hand was quite dull from the last time I used it.  I cleaned it up as best possible and tried it out since I didn’t want to take time out to go pick up some more.  Well, the blade definitetly wasn’t optimal, but it was just enough to get the job done.

I then pulled out my big miter saw and cut down the line to free all the individual fuel drain valve blocks.

Later on the evening I Alodined the fuel drain valve mounting hard points.

•••

24 May 2017 — Today I started back in on the right side cockpit.  I flared the tubing for an AN fuel line fitting, shaped the engine feed fuel line and ran it off off the fuel boost pump.  I then did the same thing for the left sump tank feed line running it aft from the fuel selector valve.

Here’s a closeup of the fuel selector valve with the left fuel sump feed line freshly attached.

I swapped out the clockable 90° AN fitting for a 45° fitting on the fuel boost pump to get a better exit angle to the sidewall and then aft.

•••

25 May 2017 — I started off today doing a bunch of research on the Silver Hawk EX fuel injection system to figure out the mechanical lever configurations and how the throttle handle and mixture lever would control the fuel injection servo.  I needed this info to get a good approximation of where the throttle and mixture cables would be run down the fuselage sidewall.  This allowed me to better figure out where my oil lines will go inside the cabin for the oil heat system.

I also did a fair amount of research on the FT-60 “Red Cube” fuel flow sensor installation, as well as the Matronix pulsation damper I have on hand.

•••

26 May 2017 — I realized that I was remiss in showing a pic of the fuel selector valve with all the fuel lines in place, so here’s a shot.  Also, to the right you can see one of the new Clickbonds.

•••

27 May 2017 — I had an issue today with the right side armrest today that needed some cutting to solve.  I simply couldn’t get the armrest mounted since the fuel lines were in the way.  I wanted to be able to mount the armrest since I was going to install the “map” pocket permanently to get a final idea of fuel line routing… and just to get it done!

I taped in my 12″ flexible decimal ruler to get a good estimate of what the pilot thigh support ribs profile will be, and then cut it out.  Of course, I also wanted to get this area cut out in my continuing effort to get the pilot area sorted out as well to allow me to move on to the nose build.

One of my tasks was to make foam fuel line mounting brackets that –at least the bigger one– will need to be glassed in place when the fuel sump right forward wall extension piece gets glassed in.  I’ll most likely wait on the smaller bracket.  If you’re wondering why I went with foam and am using fiberglass to secure the fuel lines, I actually got the idea when I queried Nick Ugolini on it.

To use Adel clamps, I would have had to spread out the fuel lines much farther apart (unless I grouped them together, which was not something I was so keen on doing). Plus, the way the fuel lines go through the pilot seat back opening, they either have to have a significant bend or slant to get them to the sidewall an inch away to use the Adel clamps, or they still need some type of bracket built to provide the required standoff from the sidewall.

Yes, if my “map” pocket wasn’t installed I could have possibly drilled or removed the edge of the pilot seat back that sticks out from the sidewall, but I wouldn’t prefer to do that anyway . . . and of course it’s not an option in this case.  To be clear, I have been researching this topic online and talking to folks for over a week now regarding the securing of fuel lines, and when Nick mentioned this, it was simply an Aha! moment.

In the pic below you can also see the foam fuel line bracket that I floxed & glassed in place.  For this I simply used 1 ply of BID on each side.  After I ensure the fuel lines are in the correct position, tomorrow I’ll secure each fuel line in place with flox in its respective notch, then I’ll layup a 1″ wide ply of BID over the entire edge of the fuel line bracket, from floor to sidewall.  I’ll most likely mount the other fuel line bracket, and probably even get the fuel lines nice and situated, then mounted at the pilot seat bulkhead opening.

I actually did this early evening before it got too dark, but I placed it here for better topic flow.  I went out to my shed and pulled out the big miter saw to cut this 2.5″ x 2.5″ x 3″ wide 6061-T6 angled aluminum bracket piece for the initial fuel selector valve bracket.  This bracket will be the base for the “S” curve bracket that will attach to it. In turn, the “S” curve bracket will be what the fuel selector valve actually mounts to.  The position shown here is way low since I just have it setting there.  However, the left/right position shown is pretty much spot on.

Here’s a shot of it free & clear.

•••

5 June 2017 — Today I set the fuel pulsation damper in position and spent a bit of time dialing in the position and tube bend of the fuel line from the pulsation damper to the FT-60 Red Cube fuel flow sensor.  In a perfect world the pulsation damper would be mounted immediately forward of the red cube, but I just couldn’t get both fitted into one spot with the space I have on hand.  In other words, I couldn’t get them paired together neither where the pulsation damper is now, nor where the red cube is in the hell hole.  For flow requirements for both, this was the best compromise and I believe the damper should still work well to smooth out any odd pulses generated by the system, and allow quicker recovery of fuel flow sensing after the fuel pump is turned off.

[NOTE: ELECTRIC FUEL BOOST PUMPS ARE KNOWN CULPRITS TO CAUSE THE FUEL FLOW READINGS TO BE OFF WHILE THE PUMP IS ON… THE MAJOR DRAWBACK OF MOUNTING THE RED CUBE FORWARD OF THE MECHANICAL FUEL PUMP, WHICH ITSELF DOESN’T CAUSE ERRANT READINGS AND IS THE PREFERRED MOUNTING (MANDATED) LOCATION OF THE MANUFACTURER.  I’M MOUNTING IT ON THE COLD SIDE OF THE FIREWALL SINCE IT’S WAY EASIER, SAFER (IMO) AND BESIDES THE JUMPY READINGS ONLY DURING FUEL BOOST PUMP OPS –WHICH HAS VERY MINOR, NEGLIGIBLE AFFECTS ON OVERALL FUEL USAGE DATA– WORKS FINE ACCORDING TO A LARGE NUMBER OF OUR RV BUILDING/FLYING BRETHREN].  

Here’s a shot of the fuel line traversing through the back seat bulkhead and connecting to the FT-60 Red Cube.  Mounting the fuel line through the seat bulkhead this way of course required me to flare and terminate the fitting on the aft side, then after drilling the hole I had to then ensure I bent the tubing just right to intersect & mount to the pulsation damper before flaring and terminating the fitting on the forward side of the seat bulkhead.

Here’s a shot of the FT-60 Red Cube fuel flow sensor.  It’s hanging in space right now, but once I get a small order that I placed with ACS I’ll have the hardware to build & mount a bracket for it to attach to.  I’ll note that one of the requirements for fuel flow OUT of the red cube is to have the fuel flow upwards (specifically, not “downwards”) to ensure no reading-deviating cavitation occurs.  There should be 5-6″ of straight plumbing after the fuel exits the sensor, but many have reported that a 45° fitting has worked just fine.  With this final location I may very well be able to use a straight fitting and obtain that desired 5-6″ straight line out.  Either way, I think this configuration will be acceptable for good fuel flow sensor readings.

•••

8 June 2017 — Today before I could proceed on installing the right wall main tank feed, I needed to mount the fuel pulsation damper in place to avert a more difficult install later on.

I actually went back upstairs and brushed up a bit on installation techniques & methods before diving in.  Also, on a FaceBook post a few weeks back, Nate Mullins stated that he had used DEL fitting seals with very good results, and since I was getting ready to submit an Aircraft Spruce order, I put them in the basket…. talk about good timing, eh?!

Here’s a closeup of a DEL fitting seal.

After getting the pulsation damper mounted, along with the fuel line traveling aft from it to the engine (via the FT-60 ‘Red Cube’ fuel flow sensor), I then floxed in place the main tank fuel feeds to each sump tank & the sump vents.  After I got the flox set where I wanted it, I then peel plied it to match the top edge of the side walls fairly closely.

In addition, if you look closely in the pic below, you can see that I floxed a Clickbond in place for the fuel pulsation damper Adel clamp.

•••

9 June 2017 — Today I made this video providing an overview thus far on my fuel sump & fuel system.  I also do a water flow test using a marble, which I momentarily misplaced, hence the blog title.

I then laid up 2 plies of BID over the fuel pulsation damper Adel clamp click bond.

And 3 plies of BID over the 3 click bonds that will secure the FT-60 ‘Red Cube’ fuel flow sensor bracket to the Hell Hole sidewall.

Speaking of which, here’s the bracket for the FT-60 ‘Red Cube’ fuel flow sensor right after I drilled the 3 lightening holes on the lower portion of it.

And here’s the FT-60 ‘Red Cube’ fuel flow sensor bracket set in place after the click bond BID cured.  There is some gunk at the base of one of the click bonds that I need to clean up so that the bracket will mount fully onto the click bonds, but I’ll save that until tomorrow.

•••

10 June 2017 — Today I had an issue cleaning the threads on a click bond that I used some leftover E-Z Poxy flox to mount the 3 click bonds for the Red Cube mounting bracket.  As soon as I got to that first little oomph, I could tell the click bond snapped free of its bonded base.  Of course, then I didn’t have a good way to get the nut off since the base was spinning feely!  After messing around with it for a bit, I simply used my Dremel cutoff tool and ridded myself of the useless post & nut.  For the next 2 click bonds I was of course much more cautious, gentle and moved much slower, grumbling and NOT happy with E-Z Poxy the entire time!

Coincidence?!  Maybe so, but this builder will never find out because I’ll simply stick to MGS (or 5 min glue) from here on out.  Thus, my cool 3 click bond posts for the Red Cube mounting bracket are now simply 2 posts, and I’ll flox on the mounting bracket for extra measure when it goes on.  Since these sit on the fuselage layup for the main landing gear mounting brackets, I’m not messing around with digging that click bond out or redoing it…. I just won’t chance doing more damage to some very critical fiberglass.  I’ll just chalk it up to being in the aptly named “Hell Hole” and move on . . . with lesson learned in hand.

•••

12 June 2017 — I started out today wanting to get the FT-60 Red Cube fuel flow sensor mounting bracket finished so that I could Alodine it with the armrest mounting brackets that I planned to prep as well.

I did get the FT-60 bracket configured with the mounting bolts drilled and the corner nutplates’ rivet holes drilled out as well.

I countersunk the rivet holes in prep for using flush rivets.

Thankfully, after the click bond disbonding issue, I was able to get the bolt holes aligned correctly, since the Red Cub sits on its bracket at a slight angle left-right to align properly with the fuel feed tube.  I added the nutplates in the pic so you can get a sense of how it all goes together.

Also, after pondering it for the last day or two I decided that with all the fuel lines, fittings & components in the back seat area –and the entire cockpit actually– that the fuel vapor sensor that I bought while I was in Qatar was going back into the lineup.  I just think that it’s the prudent thing to do to have the earliest possible warning of any fuel leak, at the vapor level before it gets any bigger/worse.  I decided on an out-of-the-way spot for the sensor element and will mount it there (it’s just mocked up here) with 2 click bonds using?! . . . yep, MGS!

•••

13 June 2017 — Well, I have to admit that when I started off this morning by using 5-min glue to mount the fuel vapor sensor module’s clickbonds in place, I realized I have may have been a bit too thick with the praise for MGS over E-Z Poxy when it comes to mounting clickbonds, since I do quite often use 5-min glue to initially hold them in place.  However, I will still state that I have not had an issue with either 5-min glue or MGS when it comes to clickbonds.

Moving on.  I prepped the bottom of the fuel vapor sensor module with clear packing tape, then put some dabs of 5-min glue on each prepped clickbond and set it in place.

A bit later I laid up 2 plies of BID over these clickbonds and then peel plied the layup.

I then Alodined the armrest mounting brackets and the FT-60 Red Cube fuel flow sensor mounting bracket.

I then riveted the 90 deg. corner -4 nutplates in place on the FT-60 Red Cube fuel flow sensor mounting bracket.

Here’s a shot of the bottom side of the bracket (my Alodine is a bit old, and unlike a fine wine it doesn’t get better with age… maybe that explains some of the splotchiness on my bracket… not sure…)

And here is the  FT-60 Red Cube fuel flow sensor mounting bracket after I floxed ‘er up and bolted ‘er in!

 

•••

14 June 2017 — I had errands to run today, and then dinner with friends tonight, so before I headed out I wanted to get some stuff mounted to ensure my efforts in installing brackets & mounting pads were successful.

First up was the FT-60 “Red Cube” fuel flow sensor.  I used a couple of thick washers on the AN4-17A bolts and put it in place.  The spacing was tight, but I got the bolts in nice and snug with the unit correctly aligned with the fuel line coming aft from the fuel boost pump. Thus, the fuel flow sensor install is marked off the list as complete!

I also double checked the clickbond spacing for mounting the fuel vapor sensor element, and they were spot on.  In the pic below you can also see the new GIB right armrest mounting tab just above the engine fuel feed line.  Lastly, you can see the mounted fuel flow sensor peaking out from behind the back seat.

•••

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Project Update

Hey Guys,

I left my last project update for a while so everyone would have a good chance to read it.  

So this is it folks!  I hope for this to be the final push from now until Rough River to get the main assembly of the aircraft completed.  That’s my goal.  Is it an aggressive timeline?!  Oh, yeah!  After Rough River, I then expect the next few months to be finalizing any leftover punch list items and the finishing & painting! 

Over the past few months I’ve had some unexpected scope creep in my build, which is all well and good because the build is THE project.  As you know I rewickered Marc Zeitlin’s new AEX system which took a fair amount of time to implement, then I had planned on knocking out a good dozen electrical related items so that I could close up the nose.  I got a bunch of those completed, but kept finding myself not being able to really close out wire runs, confirm install spacing configurations such as the pitch trim unit, etc. because I couldn’t sit in the airplane and confirm what I had dimensionally without the actual pilot’s seat in place.

This drove me to move my immediate project line of demarcation from the instrument panel, back one more bulkhead to the pilot’s seat.  I was then going to knock out the pilot’s seat area –including the thigh support & cover– but there was a glaring prerequisite to doing so: I couldn’t get the pilot’s thigh support configured & installed without the fuel lines in place!  Thus, I needed to move the project line of demarcation back one more bulkhead and knock out the thigh support sump tank to get the fuel lines run in reality without merely estimating some more with a fake, mocked up install.  

So the immediate order of battle right now is to finish the fuel sump (including configuring the majority of the back seat area), and then the pilot’s seat area. These, in turn, will allow me to finalize the configuration of the nose components. At which point I will focus on the building the nose while concurrently finalizing the wheel pants install (nope, haven’t forgot about those!). Then the canopy install will be after that.

Hang on to your hats folks, it’s about to get busy all up in here!

Cheers!

 

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  9. Chapter 21 – Interior layup cleanup Leave a reply