Flybaby is flying again

J

jesse

Touchdown! Greaser!
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Jesse
After nearly two months of the Flybaby being down because of various maintenance issues I was able to fly it yesterday just before sunset. Quite a few things were repaired: cracked oil tank, cracked no 3 cylinder, new spark plugs, wing anchor bolts, wing anchor plates stripped, inspected, painted, new flying wires, new turnbuckles, and a bunch of other things.

I was a bit nervous during the takeoff roll. It like always though quickly took flight and I started to feel a bit more relaxed once I got above parachute altitude. Circled the airport for about 45 minutes up high at a high power setting. Had to land since it was getting dark.

A hell of a view to come back to though:
yAFMgYq.jpg


Now I move onto installing panel lighting and potentially switching to disc brakes.
 
Glad that you were able to get it back together and have a nice evening for a break-in flight.

The first flight after a long downtime and MX is always something a bit unnerving to me as well. Certainly there is evidence that shows we should treat it with respect, given the number of post-MX crashes.

Looking forward to seeing the lighting result.
 
Jealous! Instead of flying I pulled a gear leg fairing to start working a mod/repair...

It was beautiful last night.
 
Always get a bit nervous on the first flight out of maintenance. Glasair was out for over a month with multiple repairs last month as well. I was crossing my fingers on take off in that everything was put back together again right.
 
jesse said:
Many times better but not absolutely perfect by any means.
Click to expand...


I wonder if a different handheld would work. Maybe better shielding or better squelch, or worse....

Gotta be a few around that you could try.
 
Ted DuPuis said:
The first flight after a long downtime and MX is always something a bit unnerving to me as well. Certainly there is evidence that shows we should treat it with respect, given the number of post-MX crashes.
Click to expand...

Amen to that. On a post-MX flight in a Duke we came in to land, pulled the power back, but the right didn't respond...power stayed up. Yanked the right prop back to feather and landed. Found the support bracket for the throttle cable hadn't been tightened. A go-around attempt would have been, uh, problematic....be extra prepared on those flights.
 
LDJones said:
Amen to that. On a post-MX flight in a Duke we came in to land, pulled the power back, but the right didn't respond...power stayed up. Yanked the right prop back to feather and landed. Found the support bracket for the throttle cable hadn't been tightened. A go-around attempt would have been, uh, problematic....be extra prepared on those flights.
Click to expand...

Yep, that would've been bad. Also why it's nice to have a long runway for the first flight.

Then again, you WERE flying a Duke. :D

(I still want one)
 
bnt83 said:
I wonder if a different handheld would work. Maybe better shielding or better squelch, or worse....

Gotta be a few around that you could try.
Click to expand...

I think at this point 80% of the noise has been cut. Now I just need to check grounds and perhaps give those magneto filters a shot.

Anyone care to explain how this should ideally all be grounded so I can confirm mine is all right:

Wooden airplane
Antenna in fuselage
Handheld radio in cockpit
Battery powered electric system in cockpit

The more detail the better. I've heard and read different things about how the p lead ground and shielding should be grounded. Basically how exactly should the p lead and mag switch be wired?
 
Spam can experience...

#1 ground strap from the engine to the other side of the rubber engine mounts, grounding the engine to the rest of the airplane.

#2 P-lead shields are terminated
a) onto a screw of the magneto
b) ground lug of the mag switch

#3 Mag switch may or may not be grounded to the airplane by a jumper.
 
Velocity173 said:
Always get a bit nervous on the first flight out of maintenance. Glasair was out for over a month with multiple repairs last month as well. I was crossing my fingers on take off in that everything was put back together again right.
Click to expand...

It's especially nerve-wracking after replacing a Fly Baby's wing bracing wires, like Jesse did. Remember, they hold the wings on...any failure of workmanship or material is going to have very dire consequences. We replaced the wires on the club Fly Baby 25 years ago, and it does make ya think....

Jesse, as far as the brake replacement goes, I replaced my wheels and brakes with Groves a couple of years back and they've been great....

Ron Wanttaja
 
jesse said:
I was a bit nervous during the takeoff roll. It like always though quickly took flight and I started to feel a bit more relaxed once I got above parachute altitude.
Click to expand...

Did you get the old open-cockpit coaming with the aircraft? When you're wearing a 'chute, it's easier to get out and walk with an open cockpit....

Ron Wanttaja
 
A sheet of copper makes a good ground plane, unfortunately it also ads weight.
 
Henning said:
A sheet of copper makes a good ground plane, unfortunately it also ads weight.
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I'm not sure that is really the problem. The antenna in theory has a ground plane. It's a whip antenna that basically looks like this inside the fuselage:
http://upload.wikimedia.org/wikipedia/commons/6/6b/Antenne_gp_vhf_3.jpg I haven't measured yet to see if all of that is the right length.

Whether or not the ground of that antenna is the same ground as the engine, magnetos, and electric system is another question entirely.
 
wanttaja said:
Did you get the old open-cockpit coaming with the aircraft? When you're wearing a 'chute, it's easier to get out and walk with an open cockpit....

Ron Wanttaja
Click to expand...

I did but I think it has warped over time. It's a major struggle to get it onto the airplane and is really hard on the fabric to install/remove with any frequency.
 
AdamZ said:
Jess where did you end up finding the new cylinder?
Click to expand...

A cylinder shop removed it from an A65 they had overhauled for someone awhile back that the person never paid for.
 
jesse said:
I did but I think it has warped over time. It's a major struggle to get it onto the airplane and is really hard on the fabric to install/remove with any frequency.
Click to expand...

Do you wear the 'chute all the time, or just after major repairs? Is the Flybaby aerobatic capable?
 
Bill Jennings said:
Do you wear the 'chute all the time, or just after major repairs? Is the Flybaby aerobatic capable?
Click to expand...

All the time. It is aerobatic capable but if I wanted to do aerobatics I would buy a better airplane with more safety margin.
 
jesse said:
I'm not sure that is really the problem. The antenna in theory has a ground plane. It's a whip antenna that basically looks like this inside the fuselage:
http://upload.wikimedia.org/wikipedia/commons/6/6b/Antenne_gp_vhf_3.jpg I haven't measured yet to see if all of that is the right length.

What the hell is THAT thing? Why not just take a picture of what you actually have so that we can see it?

Whether or not the ground of that antenna is the same ground as the engine, magnetos, and electric system is another question entirely.

IT matters not whether the grounds are the same. THe antenna and ground plane are a system unto themselves.

Jim
Click to expand...
>>>>>
 
weirdjim said:
>>>>>
Click to expand...

The same style of antenna. A whip with rods on the bottom to act as the ground plane. No pictures because it's pretty damn hard to take pictures of an antenna buried in the fuselage and because I'm not at the airport at this moment in time.

To me it was logical to make sure the entire ignition system is 100% correct before moving into the antenna especially since the antenna is so inaccessible.
 
weirdjim said:
Four strips of 1/2" 1 mil copper tape works every bit as well and adds negligible weight.

Jim
Click to expand...

Could be, I'm only familiar with what the SSB rigs I deal with call for, I'm not a tech, I just follow the instructions.
 
Henning said:
Could be, I'm only familiar with what the SSB rigs I deal with call for, I'm not a tech, I just follow the instructions.
Click to expand...


If you are talking about the HF SSB rigs for overwater, the SHORTEST quarter-wave for a ground plane is about 8' in each direction from the center of the antenna. That is the SHORTEST. Mostly you are talking about dozens of feet, so all that copper plate is giving you is ballast.

Jim
 
jesse said:
The same style of antenna. A whip with rods on the bottom to act as the ground plane. No pictures because it's pretty damn hard to take pictures of an antenna buried in the fuselage and because I'm not at the airport at this moment in time.
Click to expand...


I think we've found PART of the problem.:yes:

.
.
.
 
weirdjim said:
If you are talking about the HF SSB rigs for overwater, the SHORTEST quarter-wave for a ground plane is about 8' in each direction from the center of the antenna. That is the SHORTEST. Mostly you are talking about dozens of feet, so all that copper plate is giving you is ballast.

Jim
Click to expand...

They're wired to the antenna tuner box and usually end up in the dog house under the wheelhouse, and yeah, they're big.
 
Henning said:
They're wired to the antenna tuner box and usually end up in the dog house under the wheelhouse, and yeah, they're big.
Click to expand...

Are we talking airplanes or boats? If we are talking saltwater boats, you've got a ground plane roughly ten thousand miles in any direction.

Jim
 
weirdjim said:
Are we talking airplanes or boats? If we are talking saltwater boats, you've got a ground plane roughly ten thousand miles in any direction.

Jim
Click to expand...

Boats, and salt water boats. Never figure out why people don't want to use Dynaplates on the bottom.:dunno:
 
jesse said:
Wooden airplane
Antenna in fuselage
Handheld radio in cockpit
Battery powered electric system in cockpit

The more detail the better. I've heard and read different things about how the p lead ground and shielding should be grounded. Basically how exactly should the p lead and mag switch be wired?
Click to expand...

Ground the mag wire shield at the engine only, not at the switch. The p-lead should be inside the shield except a very short portion at the engine and mag switch. I have no mag filters (slick mags). Be sure the wires are secured well, if not they will eventually break due to vibration.

I've got a Pietenpol with your exact setup and I have no mag noise at all. External antenna on the bottom of the nose, and I've been able to communicate with it up to 125 miles, air to air. This is with a VXA-150 handheld. The antenna is made of a brass brazing rod, and the aluminum lower nose cowl is my ground plane.

Make sure no radio wires are bundled with the mag wires (i.e., keep the radio power, antenna, PTT, and other wiring as far as possible from the p-lead).

What are you using for a ground plane for your antenna?
Also, for best performance the tip of your antenna needs to be as far as possible from all other metals, ideally at least the length of the antenna. This won't affect the noise issue, but will help your transmit/receive performance.
 
It would make sense not to ground the ground lug on a switch to the airframe because first it doesn't need to be and when the switch is in the "on" position the shields would be floating like a true radio shielded wire should be.


 
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This is how mine is wired, the ground lug to the airframe and also grounded at the engine. There is mag noise only really noticable when manually beaking the squelch and not during normal communications.

 
bnt83 said:
How is the switch grounded to the engine? What switch do you have?
Click to expand...

The shield is used to ground the p-lead at the switch (by closing the switch), exactly as shown in your first diagram.
 
bnt83 said:
It would make sense not to ground the ground lug on a switch to the airframe because first it doesn't need to be and when the switch is in the "on" position the shields would be floating like a true radio shielded wire should be.
Click to expand...

Agreed. If you ground it at both ends, it creates a ground loop, i.e., parallel ground paths, which can induce noise since the two ground paths will be of different impedences.

http://en.wikipedia.org/wiki/Ground_loop_(electricity)
 
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