Sbach Recovery

This has been a lot of busy work... at time frustrating, but all in all, success.

The first big project was getting the frame damage repaired. Very much like setting  bones, and installing support to the weakend areas. The wasn't hard.

The only damage to the cowl was some abrasions to the bottom. Sanded out, painted, done.

The latch work. Took a bit of MacGyvering, but it fit.

The second big project was the landing gear. Replaced the hardpoint and rebuilt the structures in the fuse to which it attaches.

I also had to build a little hard point for the fuel vent.

All done with the undercarriage! Not shown is the tail wheel which came off. Built up the hardpoint and reinstalled. The red streak is still there, just washed out of the pic.

The Evolution two needle barrel carb. I washed out the carb and the cylinder in case any dirt got in. When I started the engine it was way off and wouldn't run steady, no matter what I did to the needles. When the throttle moved it pulsed irregulalry, even when it ran steady, and would not move through the mids well at all. Something was wrong with fuel delivery. I took the carb apart and cleaned it, but there wasn't any dirt. I flushed out the cylinder and checked the spark plug, reset it. Didn't fix the problem. I decided to replace the vaccum line, and reset the needles exactly to factory, and that did it! It stutters just as it reaches WOT as it always has, but it's acceptable.

The latch arm broke off. Just like that. This was a frustrating part, that and dropping the plane on the tail and cracking the end of the rudder, but that's for another day. So I had to literally tear it out... Rebuilt that and replaced it with the second latch (they came in a pair). Finished, and then went to open it and, damn, it snapped too! So I will just use a micro screwdriver to open it to install and remove the wings.

The aluminum nose cone was scratched up. I sanded it and used a "chrome" paint that really was just silver... that was annoying.  Will order a new one.

To do list:

1. Install the cowl.
2. Repair the minor damage to the tip of the rudder.
3. Repair and install the wheel pants.
4. Snug up the rudder lines.
5. Work on getting the canopy to sit better. 
6. Recheck CG
7. Crash it again.

In other news, the RCGF 30cc engine for the MX-Bach arrived from Joe Nelson at RCGF! That will be the next project.

Let me know when this starts being fun...

In between local storms, the day calmed remarkably and I took advantage of it.

If you can't be good, it's good to be lucky. I was lucky.

The SBach started right up, and ran impeccably! Idled sweet and clean, no hesitation transitioning to WOT. Let her sit, and she purred. Opted to go ahead and take her up. I had moved the battery pack back, and added a second so I could just switch leads when I flew the first one down, since I needed some weight aft of the CG. This worked and she was nicely balanced. I took off, heading north and flew her out to the far end, turned and flew back towards the field. She sounded smooth and sweet, power and performance, turned back north and then decided that I wanted to increase the expo on the surfaces, it's at 35 but still sensitive. I turned her back south on the downwind, and as I started to turn to base, I realised something was wrong she suddenly righted her self to level flight. It was too quiet... and she was getting sluggish. Did she brown out? I had control again.  (I wondered if having the vertical antenna in front of the duck would create a dead space aft, and this would be the orientation that Howard would block both antenna, did it?). Dead stick, the engine stalled. Since I had been at the end of the downwind leg. and she was dropping to stay aloft, I started a turn to base and realised she wasn't going to make the runway, and the upside of the hill is sure death. I turned back away towards the north, but she wasn't going to make the turn, I leveled out. I had no idea where she was in relation to the chain link fence that separates the dump from Mt Hudson and the Southern Ents. I feared landing in the active dump as there are nothing but metal dumpsters, and a bit of open hard dirt driveway. I could only try to keep her level as her nose finally dropped and she disappeared.

I had no idea where she actually ended up, so I drove down to the gate and walked the south east corner, challenging the ticks and poison ivy. Nothing. Didn't see her in the trees, or beyond the fence in the south woods. She wasn't in the cabbage.

So reluctantly I headed into the active dump. If she went in there surely she took a dumpster out or was in a million pieces.

Lucky. I found her in the middle of this driveway between the dumpsters next to whatever detritus that yellow thing is. Smack dab in the middle. Flat. She landed flat! Should have taken a pic from here before I picked her up. I think the vortex generators kept the lifties under the wing to the last moment.

Yeah, that's Clarence on the other side of my car, just arriving as I was leaving. Dumpsters...

The big dump was right in front of her.

This is what I saw as I walked up.

It was like just a hard landing! 

If you suck as a pilot it pays to be lucky.

Hatch latch is missing. The fuse must have flexed and pushed out the canopy taking the hatch.

Most ot the internal damage was on the port side.

Took out her spark and the blade.

Starboard side damage is light.

Will be rebuilding the wheel hardpoint again. The wheel pants came off and one of the wheels, but I have all the parts, and the suspension looks fine.

Sheared the tail gear clean off.

Cracked the bernoulli flap.

The gear. The canopy is fine.

Small puncture from the wheel pant as the gear came off, starboard wing.

The port wing looks to have some mild internal damage.

The control horn is intact, came out, port wing.

All in all, a pretty lucky ending. I have no idea why the engine quit, it was running so nicely. I had idled back to take some speed off for the landing. I going to take a break with her for a few days then rebuild and figure out what happened.

What is it with me and landing gear?

BEAUTIFUL DAY today. Took the Sbach and the Pulse XT60 out this afternoon. The Pulse started, ran fine, flew well, but discovered a small problem. The Sbach started but wouldn't run right. I removed the cowl, tuned her and she ran fine, but lacked something. I was flying her with the 12x8x3 blade, and she didn't seem to like it. I put the 2 blade 13x8 back on, small tweaks to the needles and she found her somethin'-somethin'! She wants the two blade. Sweet.

After the third flight, the first with the two blade, she rolled out after a nice landing and her gear just came right off. Right. The. Frick. Off.

Reset the crash clock...

The fore and aft tabs on the hard plate, and glue on those two longitudinal stringers was it. Thin balsa held the tabs in front. This was just begging to fail.

I did manage to find a muffler extension length and position to keep most of the exhaust oil off the fuselage.

The Pulse flew well. Her engine still sputters in the mid ranges, sweet at WOT. But her elevator servo will twitch once or twice up when the vibrations hit on WOT. I saw this is I gunned it, both in flight and on takeoff. It does it once, pitching the nose up then goes back, aa quick up flick. I bet this is what happened  when she flipped over her wing and threw the fuse cover. Need to replace that servo I guess.

So, the gang is all here. The Sbach is already fixed, strengthened the attachments. Still looking for a used 30cc gas engine for the MX-Bach. Here's hoping the Sbach and the Pulse become dependable.

A pattern is emerging...

Is this my new thing? I get to the field and a perfectly good engine won't start. And when I get home I make a couple of random changes, and she starts.

On putting the Sbach wings on I found the extension from the reciever to the left wing servo lead had one pulled wire, and a second pulled when I removed it. Fixed that.  Then tried to start her, nada. I really didn't feel like trying too hard to fix her at the field. Couldn't do much, didn't even have a tool to remove the spark down among the fins.

At home I found a slight pinch in the fuel line from the 3-way to the engine and slung it straight. Found the ignition wire plastic spiral coat melting on the muffler extension, and slung it out of the way.  This choke-less motor needed me to manually choke the air inlet, and she started right up, but would stall at idle. Needed to re-tune her low needle, then reset the idle end point, it just has to be really rich. For giggles I had ordered a Du-Bro 3 blade spinner, and put a 12x8x3 prop on her.

Luke, my son, came out with me and took a pic.

And helped me put her together and apart.

Bad girl...

I had brought the Pulse XT60 having repaired my head-wedge mistake, but the resting winds waxed and waned to 7-8 mph, with 14 mph gusts. I could fly her fine but I wasn't in the mood.

Meh. Two days of work, then it's the 4th, so I won't be able to fly for a few days.