[79FT]: Building Things
|On:||May 16, 2019|
|In:||[Chickenhouse Charger] Electrical Rebuild|
|Tags:||6781G, MA5 Charger, Annual, electrical|
This thing nagged me for a while. The Charger did not have the Field breaker. For that matter, it didn't have the Alternator master breaker, either.
It had this weird "main buss" breaker for 60 amps, but that didn't look like the Alternator breaker to me.
So in between dealing with other things after having decided to put her thru Annual in 2019 a bit early, I was running around with my multimeter, tracing wires.
Initially, I quickly discovered that some lines were definitely not fused; like Battery -> Main Buss line, and thought I'd put inline fuses into them, and be done.
She has an old charging system; a mechanical switching voltage regulator, and a Delco Remy alternator seemingly from a tractor:
The old Delco-Remy
Voltage regulator didn't make sense. It had 4 wires (should be 2: supply and field output, or 3: supply, sense, and field output).
Alternator didn't make sense. Instead of 1 wire for Field input, it had two wires.
Additionally, Battery Contactor didn't make sense. One terminal had a wire going to it. The other was grounded....
Battery Contactor is an interesting point here. Normally, one terminal is connected to the "always hot" side of it (basically, directly to the battery) and the other goes to the Master Switch. Master Switch turns the Battery Contactor on by grounding that wire, providing the negative side to the circuit. It's a safety thing. If that wire breaks, it'll either turn the electrical off (open circuit), or it will keep it turned on (short to ground). That's it.
But, one of the terminals on the Battery Contactor was grounded... that means, that the other terminal (the wire coming from the Master Switch) must provide positive side??? Huh? But where does it get it's power from?
So to tracing we went. I spend maybe 10 hours trying to find diagrams and understand that alternator and voltage regulator hookups.
And me tracing it spelled my doom.
Now, I didn't trace the rest of it. Just the main distribution system. That was enough.
The current main power system of the Charger
Yep, the diagram is missing the main power buss. It's dangling off of the same spot where everything else that's interesting is - the Battery Contactor (marked MA RELAY) <-> Starter Contactor (marked STARTER REL) link.
So let's see what we have here.
That last bit bugged me. I couldn't find the damn thing. Even before actually tracing it, I knew that if the Master Solenoid is switched on the "hot" side, it needs to get the power from somewhere, and that only could be battery. But I didn't see any wires on the always hot side of the Master Solenoid. Only when I traced it, I actually traced the physical wire to where it goes, and then found it. It was so tucked behind the battery -> Master Solenoid wire that it was invisible:
This little !@#!S@#....
Oh; and by the way, the Master Switch is the only switch that's soldered in, and w/o any good insulation around the terminals, and over-stripped wires. So that's just waiting to short, and the magic smoke that'll be let out behind the panel when that shorts can't be stopped (always hot wire, remember?)
So I kinda went backwards here; but I thought it'd be easier to see the diagram first.
Most of connections are made on this very nicely marked terminal block:
The terminal block
All the switched power comes out there, and every wire is marked. This actually helped a lot in tracing. This block is on the side of the plane, right next to the front hole's backrest.
You know what threw me off the most with that damned always hot wire (I ended up tracing it physically)? It's how it's hooked up.
Yep, it is hooked up to that terminal block. To the terminal... that is marked.. (drumroll).... "Master Switch".
Wait.. this actually makes sense... But where's the "return" from the switch?
Ah! It's the wire that's marked.... drumroll... "Fuel Gauge"!
So really, let's look at what's going on, shall we? Zoom in the image below, it's annotated.
So let's see. We've got this bundle of wires, a lot of which are not fused, and one of which is always hot.
The Main Buss wire is the thickest one (10 gauge maybe?) that's not fused between this buss bar and the source (engine compartment).
Oh, did I mention that this buss bar is on the side of the plane near the rear instrument panel (so that 10 gauge run, and the rest of the harness between firewall and the panel is about 30 inches long)?
What else do we see there? Oh! The two little 1/16inch thick aluminum lines carrying.. fuel pressure (and oil pressure).
Shall I say more?
Shall I say that there's a fuel tank in between the front hole (passenger) and the firewall?
That the wires run along between firewall and rear cockpit along that fuel pressure line (to fuel pressure gauge)?
That if one shorts to this very nearby fuel pressure line, it'll burn a hole straight thru it, and then ignite the gas that'll start coming out?
Can I fix all of that?
Sure. But rewiring will be much much easier, because I have to touch pretty much everything. Re-running half of individual wires in a bundle is much harder than re-running them all.
So, I made a decision to rewire the plane... Sigh. Looks like I won't be flying for a looooong time.
Oh, and tell you what. Tracing wires on a biplane is dangerous. I ended up twisting my knee and pulling a muscle while trying to get behind the panel so badly that I couldn't walk (or sit) for 2.5 days :(.
Every one already knows the definition of a 'good' landing is one from which you can walk away. But very few know the definition of a 'great landing.' It's one after which you can use the airplane another time.
...Comanche, no Comanche?
|On:||May 15, 2019|
|In:||[Chickenhouse Charger] 2019 Annual|
|Tags:||6781G, MA5 Charger, Annual, baffles|
Baffle seals on this plane are original reinforced neoprene rubber, and they were in pretty beat up shape. There is a lot of gaps, they sag in places, making the seal really not that good.
So one of the things I decided to do is to redo them.
Pardon the cruddy pictures; but those ones are the only ones I have :(
One of the things I noticed immediately is that baffle seals were turned the wrong way in the nosebowl area; where the front "air ramp" joins the bottom of the nosebowl.
Here's the nosebowl and the front ramp:
Notice the circled area? Here it is, from the back:
That marked rubber seal is in the circled area. Notice it's turned the wrong way; "into" the cowling, rather than away from it? Ram air hitting that front "ramp" will "bend it in", and leak into the underside of the engine compartment - precisely where it's not supposed to go.
Naive me thought that it was just wrongly installed - the rubber needed to have been folded up and out, "into" the lip of the nosebowl.
Correct and current seal orientation
Ha! Well, Remo (the guy who built the Charger) thought different.
There's just not enough room there. Everything is super tight. The seal just won't go there and stay there. There's just no room.
Look at the above two pictures - inside and outside - again. You'll understand why. Use pop rivet line as your reference.
Here's where the problem gets worse. Ramp is really thin - so with just a mild pressure, I can make that gap between the ramp and the bowl 1/4 - 3/8 inches. Guess what happens when ram air hits it... :)
What ram air does...
Okay, so then I went digging.
I thought this was a standard bowl. I was right!
It's an old Comanche single style bowl (I think).
Looks similar? I researched further.
Here's a guy making replacement ramps for Comanches, with some good pictures.
Front ramp on a Comanche
Okay; see the difference? Comanche ramps are curved the other way.
Changer vs. the Comanche
This is cross section. Mine's on the left, Comanche's on the right. Red is nosebowl; blue is this ramp, and black is my baffle seal.
Mine is "concave". Comanche is "convex". So if I got my thinking right, this makes the Comanche version more rigid facing the wind.
Drawing from the Comanche's parts' manual confirms this proper curve.
Comanche parts manual on baffles
The parts I'm talking about are numbers 11 and 12, bottom right corner.
But how the heck do they seal them? Notice that the material on the drawing above seemingly has some "dots" on it (as opposed to the rubber material on the side baffles).
Well, back to our "remade Comanche front baffles" guy.
Forward baffles from Comanche Gear guy
Well, I guess that makes sense. Felt wrapped around the front ramp.
Felt is thick and, contacting the nosebowl, I guess, will create a good enough seal if the ramp is rigid enough. I am guessing that Comanche's ramps are way more rigid than mine due to that opposed curve.
So where are we at with all this?
Remo probably built this noseramp himself. It looks very custom. It's too thin and doesn't have rigidity - ram air will flex bend it "into" the cowling. It's not sealed properly practically along all of that bottom edge between the bowl and the ramp.
The only hope for it is that it's aerodynamic-ish and looks like a "dozer blade" - curved up. Maybe the nosebowl lip deflects the air enough for it not to go under too much:
Can I replace the current rubber seal with felt?
Maybe. The front of the engine moves. The ramp's aluminum is very light - I am afraid that if I were to add any reasonable quantity of felt to it to hold the seal tight it will warp the aluminum via relative motion of that ramp (hooked up to the engine) rubbing on the bottom of the nosebowl. Or worse yet, make a hole in the bowl.
Can I replace the ramp? Well, everything's possible; but that's a massive undertaking. That ramp / nose baffle, Comanche-style, has that compound curve, and I don't have time or skill to do it fast. 2 months? Maybe, if I get lucky. BTW this is probably why Remo did it this way - because his is just an aluminum sheet, wrapped around the front of the engine, "neck cone" style, and cut to fit.
So, what do I do?
After discussing this at length with my good friend Ben, we settled on testing this out first to see how bad the air flow going "under" will be. I can mark the bottom of the nosebowl with some tinted oil, and go fly. Oil streaks will tell me if the air is flowing under a lot, or not so much.
I'll also replace all the other baffle seals, which will improve cooling. There's a lot of gaps to RTV, too.
I don't want to replace the bottom nosebowl ones, because actually there the rigidity of old neoprene rubber seals should help...
Things which do you no good in aviation:
Altitude above you.
Runway behind you.
Fuel in the truck.
Half a second ago.
Approach plates in the car.
The airspeed you don't have.
...and 1/2 of May
|On:||May 14, 2019|
|In:||[Chickenhouse Charger] 2019 Annual|
|Tags:||6781G, MA5 Charger, Annual, Rotec TBI, baffles, prop, fabric|
Well, as usual, I got too focused on the plane and the mess I got myself into; and didn't log things as they went...
I will split the notes in multiple posts; by theme / subject. Just general notes here.
We got together with John, my IA, and continued working on the plane early April.
We pulled the prop, so that I will have access to baffles (I wanted to redo them).
John re-riveted the air takeoff flange back to the front ramp.
Meanwhile, I started disassembling the fuel system to get to the screens, including the oil sump screen, and clean them.
TBI intake airflow straightener
Okay, stop right there. See that fuel inlet, right above the air intake? See the little smudge of dope around the inlet fitting? Yep. Teflon dope. Rotec explicitly tells you not to put ANYTHING on there - there's a copper crush gasket behind that fitting.
TBI crush gasket
See all that dope above? Okay, that thread on the TBI is a female thread. Dope will be all in it, and guess what will happen when I screw the fitting back in? Yep. It'll go into the TBI fuel galleys. Right to where that spray bar is with tiny little holes in it. Not Good (c).
TBI holes plugged
I noticed evidence of possible intake leaks, so without "burping" the engine, decided to pull the intakes and replace the gaskets. This is my karma. I did that on the Cheetah just a year ago, and scraping remnants of one of those gaskets and re-chasing the threads took me about 10 hours; maybe more.
Also: interesting note: she has intake tube clamps on studs and not bolts like every other Lycoming I've seen. Old, narrow-deck cylinders :).
When we pulled it, bolts were in the thru holes on the wooden prop really tight.
Pulling the prop
She has the prop made by Frank Johnson of Performance Propellers fame, and after contacting him, he just suggested to re-drill the holes and re-coat them inside with something.
Well, I got me a 29/64 (1/64 oversize) reamer, and went to town.
But first, I needed a rack.
My prop rack
Built with a 1/2" pipe, some foam, pipe brackets, screws, 2x6s screwed to the table, and my 3/8" drive extension rod. You get the idea :). Redneck engineering galore.
Prop on the rack
This whole thing was happening over a few days by the way; and when I finally got my reamer and had time to deal with it, the holes.. extended. Wood moves!
Hey, we had much rain then, and prop "swelled" a bit methinks.
But I still decided to fill the holes as much as I could.
Even got me some nice scales for mixing System Three ClearCoat.
A filled hole
Fabric on this plane is old. Flyable from what I am being told by experts, but old. Cracking, peeling paint.
Original logs say that she was covered in Polyfiber. But the current finish looks more like Imron and the company - "flexible" automotive poly. It's cracking and peeling around areas of high wear (prop wash, etc).
Sad, sad fabric
John (my IA) wanted to take a Maule fabric tester to it; but I didn't want holes in my wings.
I discussed this with a few guys that worked with fabric their whole lives, and we came to a consensus that for now this is fine. Will just fill with silver, and keep on flying. Incidentally, that's what Glenn has been doing, too.
I worked on baffles a bit, but then, everything went downhill. We'll talk about baffles in the next post. And the downhill part, afterwards :).
You can always depend on twin engine aircraft. When the first engine quits the second will surely fly you to the scene of an accident.
...wing root fairings
|On:||Apr 06, 2019|
|In:||[Chickenhouse Charger] 2019 Annual|
|Tags:||6781G, MA5 Charger, Annual|
Only had a few hours today, so decided to concentrate on taking off the wing root fairings. As I mentioned before, the "back-side accessible" screws were set up to have nuts on them rather than nutplates. Well, I don't know about that accessibility....
It ended up being 3 hours for ~30 screws.
Root fairing off
Most of them on the back side of the wing require you reaching with a wrench thru the rear cockpit, and my arm is just barely long enough to do that successfully. Since nuts are nyloc, no way I can hold them with my fingers - they need a socket.
Some of those nuts are in a U-type channel over which the fabric is glued, and some of the holes are off-center: making it impossible to put a socket over them.
I could've ground a socket down; but I don't have a grinder - so especially one of the nuts took a while to get off. And oh, you have to do all that without dropping the nut and the washer onto the floor (and having them go into the tail). So the process looked like this:
Having magnetic sockets helped. They weren't deep enough to grab most of the fully tightened nuts because screws protruded from them. I used them as magnets sometimes, and sometimes used my magnetic "fishing for lost hardware" probe.
Now I'm writing this, I realized what I should've been doing is using a long extension and a 90 degree adapter on my socket. Damn! But this still doesn't solve the problem with some of the nuts that were hidden almost behind things that were in the way (ie, a trim control wheel's attachment structure that's welded into the fuselage).
One of those pesky nuts
I'm considering replacing those nuts with Tinnerman-type and screws with sheet metal screws thru Tinnermans. I'd put some anti-chafe tape inside the U-channel, and then Tinnermans on top of it. Since Tinnermans are long, when undoing (or tightening) the screw, they will turn and touch the side of the U-channel, which will act as a wrench.
Wing attachment - right side
And that's literally all I got done today. Just took those damn screws out.
Don't forget to keep the blue side up.
... getting familiar
|On:||Mar 30, 2019|
|In:||[Chickenhouse Charger] 2019 Annual|
|Tags:||6781G, MA5 Charger, Annual|
After getting the Charger, I have decided to fix a few basics.
Getting a bit ahead of myself, a series of coincidences (airport closed, baffles' condition, intake leak, and others) made me decide to go thru the annu... sorry, Condition inspection (damn, will have to get used to new nomenclature :) ).
Cowling came off.
Discovered a few booboos:
Since I will need some helps with skills and tools with riveting, and we'll need to pull the prop to change (and turn the right way) the seals, decided that I will put her thru annual.
Studying the systems (I was mainly concentrated on fuel and other al lines and hoses to see where things go), discovered a few things, too
Crack in inlet ramp: stop drill
Inlet ramp baffle: turned the wrong way
Inlet ramp's take-off flange - un-riveted itself
TBI - Regulator Side
TBI - Throttle linkage
Electrical fuel pump and gascolator
#1 bottom plug - in pretty good shape
Engine compartment right side
Spent the rest of the day taking off fairings and access panels. This is the first thing I thing could've been done better here methinks. Everywhere where it was deemed that the back side would be "accessible", Remo used #6-32 nyloc AN nuts on machine screws instead of nutplates. Well, some of those nuts are not accessible, and I gave up on quite a bit of them around the rear wing root fairings.
Need to standardize on fasteners' length so that I don't juggle 10 different screw sizes.
Gotta love that easy access!
Flying wires' fairing
My laborers for the day working on wheelpants
In thrust I trust.
... for Glenn
|On:||Mar 27, 2019|
|In:||[Chickenhouse Charger] Blog|
|Tags:||flying, 6781G, MA5 Charger|
I met Glenn and Judi in 2014.
This was my second Oshkosh, and the first time I noticed the Biplane Forum's Beer'O'Clock thread.
We had two "events" that year: one in the Vintage at the awesome Piper Pub (yep, the spelling is right - it was a Tri-Pacer with the baggage door that had a beer tap. The guy who owned it claimed he had an STC; but paperwork got soaked in beer and was drying somewhere). We sneaked in a large cooler of Austin sour beer then, hauling it all the way from the opposite end of Camp Scholler. I met Glenn there, and later that night washed out in his camp and was fed with a kick-ass grilled cheese sandwich, and met Judi.
The second "event" was at Glenn's airplane, parked near Homebuilder's HQ. It was a beautiful Marquart Charger, I learned then; a 1987 Golden Lindy recipient, built by Remo Galeazzi in Petaluma, CA.
That biplane was beautiful; just the right curves and not as aggressive as more modern ones like Pitts and Skybolts. It looked straight from the 1930s, with wooden prop tipping the nose. I fell in love with it.
In 2015, we've had a good crowd around the plane.
Oshkosh 2015 Biplane Forum Beer'o'Clock crowd
Glenn's Charger became a traditional spot for these beer get-togethers, and we became friends who only met at Oshkosh; but to me it felt like I knew Glenn for my whole life, and 11.5 months between AirVentures felt like hours.
In 2016, I was finally around Chicago where Glenn lived, and he took me out to his home field, Poplar Grove. Man, what an airport! Just the right kind for his plane. We spent a day there, and I think I have seen only one spam can and maybe one RV. The others were a few Cubs, a Twin Beech, a Waco, and the like. A few friends showed up, and that day I got a ride in an AcroSport bipe, and later in the evening, finally, in the Charger.
Oh man. I flew a couple sport biplanes before; and while I liked them, they were too much for this lazy guy. Just a bit too twitchy and too sensitive.
This plane? It flew just like a Grumman. Perfect control harmony. Perfect, light forces on both elevator and ailerons. It fit like a glove.
Then, that night, by the way, I started seriously reconsidering building a Skybolt (BTW, this site was started as a Builder's Log for a Skybolt). I flew one, and while I still liked the plane, I liked the Charger even more.
Especially with it's more "classic" looks (and come on, admit it, we pick biplanes for looks), and it's perfect flyability.
In 2017, we did Beer'o'Clock at my camp (I forget why.. maybe the Charger wasn't around).
And later that year, Glenn told me he's thinking about selling it. He got too much stuff on his hands, and didn't want to neglect the Grand Champion.
I thought for about a day. I loved my Cheetah, and I loved the fact that it was a "normal" airplane. I could take my 2 year old son up in it. Not in a biplane. I could take "normal" people up in a Cheetah. Not in an open cockpit biplane - at least, it's a bit more.. rough, shall we say?
But I couldn't let the plane I loved just be sold on the Barnstormers; so the next day I told Glenn I'll take care of her when the time comes. I was overwhelmed, and honored to have a chance of taking care of a piece of aviating and homebuilding history.
The MA5 Charger
She was built in 1982. From what I could gather, she was started in 1977. There were two guys who built two MA5 Chargers in a chickenhouse in Petaluma, CA. Glenn's plane was built by Remo Galeazzi, and won the Golden Lindy in 1987. The other Charger won too by the way, some years earlier :).
Remo wrote a really nice article for Sport Aviation about both planes.
Here's another article about the plane.
Glenn changed it a bit, adding the smoke system, changing the prop to wood, and tweaking the induction and fuel systems. But the plane stayed all original mostly - original engine, original fabric, and such.
Oh, and it's the Charger on Wikipedia :)!
I told Glenn to give me 6 months heads up, so that I could work out the logistics.
See, I have lots of hours to be very comfy flying any common tricycle single. I didn't have enough experience to haul a taildragger bipe across the country (Glenn moved to CA by then). I would have to learn how to fly it comfortably before embarking on the trip; and figure out the logistics.
But then, things went much faster than I thought.
At Oshkosh 2018, Glenn was telling me he's about to sell the plane. I realized I didn't have time to train enough, and that it would be better to train in the Charger from the getgo. So the working plan became me renting a large-ish truck, and hauling the airplane over to Texas with wings off.
And then, Glenn offered to fly the plane over himself, as a good bye to her. I couldn't refuse.
September 2018, Glenn told me he's gonna fly the plane over soon. I put the Cheetah up for sale, and said my last goodbyes to her November 21, 2018. Then, life and weather intervened, and we couldn't set the trip up till last weekend.
'It's warming up', Glenn texted me a week and a half ago.
A week after that text, he was wheels up en route to TX, with Judi in the front hole.
That didn't last long. An hour and change later, Glenn was stuck in Bakersfield, just at the southern tip of Central Valley, CA. All mountain passes were blocked by low ceilings...
What's funny was that I was flying.. strike that, being flown from San Jose to Los Angeles, continuing to Texas, the same day Glenn and Judi were stuck at Bakersfield. I saw the damn clouds blocking the passes. They were maybe a mile wide!!!
This delayed them by about 24 hours, but the rest of the trip was fairly smooth. They did a lot of flying after being stuck in Bakersfield for practically a whole day, and some hours the following day.
Somewhere in the desert...
Saturday, March 23, at around 10:30 AM Central, they touched down at my home field. We had very little time - their flight back home was in a few hours. Glenn walked me thru the basics. We tucked the airplane away.
Judi saying bye
Glenn and Judi...
Quick lunch, and on the way to the airport with the big planes we went. A few hours later, late at night, Glenn and Judi were back home.
It was all so fast, I was in the state of... denial? and disbelief? I started becoming overwhelmed when I got back home in the evening on that day, and opened up the logbooks.
Remo's signatures and flight log.
Glenn's signatures and notes.
The letter from Remo to Glenn, with a bunch of pictures - just pictures of this Charger being built; mundane almost; but a part of the Champion's history.
I ended up writing this into my logbook:
First 6781G log entry in my log book
I now am a caregiver of a piece of aviation, homebuilding, and EAA's history.
And, I am no longer planeless! She needs a bit of cleaning and a touch of TLC, and to learning how to fly her we go!
The Chickenhouse Charger!
Don't drop the aircraft in order to fly the microphone.
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This website only shows how I did things in my various projects. These pages are for information and personal entertainment only and not to be construed as the only way, or even the perceived correct way of doing things. You are responsible for your own safety and techniques.