Aircraft Restoration - 1972 Cessna 172L

Picked the airplane up -- home safe

Well - the weather was great yesterday (5/4) although a bit of a bumpy ride. Craig Lesinski (Mansfield based) gave me a ride up in his Zlin:

http://mansfieldlanding.com/forum/photos/mansfield_airport_local_pictures/picture360.aspx

http://mansfieldlanding.com/forum/photos/mansfield_airport_local_pictures/picture358.aspx

We had to stop in Montpelier VT for fuel due to the 25 knot headwind and the fact that the Zlin only carries 22 gallons of fuel. It took us 2.6 hours going up and only 1.6 coming home. In Montpelier I found a Beech 99 owned by Wiggins Airways:

http://mansfieldlanding.com/forum/photos/just_great_airplane_related_pictures/picture361.aspx

Here is a air to air shot of the Zlin on our way back home at 5500 feet:

http://mansfieldlanding.com/forum/photos/air_to_air/picture359.aspx

And here are a few shots of the Skyhawk back in our hangar:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture356.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture357.aspx

We just need to put all the plastic back in the interior and we will have COMPLETED our "Better than New" 172.

Week 11 --- Completed

Got the call today that the plane could be picked up this coming weekend. We will watch weather and make the decision on which day is best. The plane could have been completed a few weeks ago but with Sun-n-Fun we decided to wait and get the plane at the end of April.

Here are a few shots up at the paint shop. I will put more up when we get the airplane home.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture343.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture344.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture345.aspx

Week 9 --- Time to pull the covers

Well the painting is done - the interior has been painted and the covers are starting to come off. Here are some great shots:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture330.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture331.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture332.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture333.aspx

All the parts will not go on an we should have a completed plane shortly.

Does this paint job look great ?

Week 8 - Stripe Masking

I got some more pictures today. The airplane is completely painted white and they are laying out the masking for the paint scheme. The masking is computer generated to get the curves perfect. I picked a Cessna 2006 172SP paint scheme to use on our Hawk. Here is an example from the Cessna website.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture322.aspx

Our Airplane should come out like this with a slight modification to the registration numbers. On ours we changed the slant and added shadowing in grey -- should look pretty good. Here are the pictures of the masking. Note that the N-number has been changed to N157DF.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture318.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture319.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture320.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture321.aspx

The still need to complete the stripes, paint the interior and put the airplane back together. With Sun-n-Fun on the 17th they are targeting to have the airplane completed the last week of April -- we cannot wait........

*** Saturday Update:

The gray and the red are down. Once they paint the last color (Burnt Orange) they will clear coat all the colors. Then the airplane interior and door jams get painted, the parts go back on and we are done...... Here are a few shots of the red color applied:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture324.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture325.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture326.aspx

More pictures this afternoon (Saturday) with all the colors down. A little hard to tell with the mask but still pretty cool:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture327.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture328.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture329.aspx

Week 5 - Priming

Got some more pictures to list today. Here is a shot of the fuselage all ready to prime:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture285.aspx

They should be priming it this week.

Here are some pictures of the control surfaces all primed and ready for the base coat of white paint:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture286.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture287.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture288.aspx

Some more pictures are in with the fuselage primed - - here ya go:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture290.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture291.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture292.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture293.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture294.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture295.aspx

Starting to get excited.............

We may get her back at the end of the month.

Week 2 - Paint Removal Process

I just received some more pictures after the second full week.

The fuselage is down to bare metal and almost ready for etching and alodyne. They are now working on all the control surfaces and the cowling:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture281.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture282.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture283.aspx

Week 1 - Paint Removal Process

I got some pictures today from the paint shop. They have removed all the control surfaces and started the paint stripping process. A messy job to get the airplane back down to bare metal.

Here are a few shots taken 2-19-2007:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture274.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture275.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture276.aspx

And here are 2 more shots the following day:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture279.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture280.aspx

N19662 at the paint shop......

We dropped off the Cessna today in Northern Vermont, Franklin County (KFSO):

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture271.aspx

The paint shop is Prestige Aircraft:

http://www.paintaircraft.com/

They told me that they would send pictures during the painting process.

I will send them up as I get them.

She Can Fly !!!!!

We have been pushing the last few weeks to get the airplane flyable before we needed to be at paint. The paint date is 2-15 and we wanted a few hours of flying before we headed off to northern Vermont.

The radios were built up on the bench and installed last weekend. Wiring was completed and the radios shook out on the ground this week ..... and this morning we flew. What a milestone !

Here we are landing after our first 0.8 hour maintenance check flight:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture267.aspx

The plane flew fine with just a few minor issues to sort out. We were able to do that back in the hangar and get another quick flight around the pattern before dark. We will now do a few hours of flying and then head up to Vermont to deliver the plane for paint towards the end of next week. Unless I can get pictures during the paint process we may have a 6 week period of no action here (on the Cessna).

Some other major things to point out that we completed since the last we spoke --

Nose Gear - the nose gear was removed from the airplane, cleaned, rebuilt and painted. This should give us many trouble free hours:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture265.aspx

Seat Belts - If you know the 172L, the seat belts were pretty basic with a separate shoulder harness that you had to clip in. Well, the new Cessnas have really nice belts (like your car) with intertia reels and all... Here is a picture of the only mod we needed to do to the airplane to accept the new belts. These are the 2 front inertia reels mounted on the top box beam:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture266.aspx

The panel - cannot resist showing the completed panel. We still need to do some touchup to the panel above the audio panel where we mounted the new "master caution panel", but I think you will agree there is a slight improvement over the original 172L design. Shown first is the original panel and then the completed "custom" panel"

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture151.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture268.aspx

WOW !

See you after paint.........

Starting to look like an airplane again.......

Well the new year is here, we are back to work at our real jobs and progress on the 172 has slowed down again. Last weekend we were up in Manchester NH for the kickoff of the FIRST 2007 event. and did not get too much done on the Cessna. For those of you that are not familiar with FIRST (For Inspiration and Recognition of Science and Technology) it is a great program where mentors (us) take a bunch of high school kids and embark on a 6 week journey to engineer and build a 120 pound robot. You can check it out at http://www.usfirst.org and if you can....... please, get involved.

Oh yes and last Sunday (7th) was around 50 degrees and the Stearman would not sit still in the hangar........

So what did we get done and what is left to do before we go to paint on Feb 15th? -----

Radio Rack - the radio rack is in my basement and I finally started wiring it. A few more nights and it will be ready to go into the airplane. Note on the following photo that we made band clamps to hold the entire rack together:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture261.aspx

This entire assembly will slide into the tray and gets screwed in at the front. This wiring to the aircraft is via connector so the entire radio rack can come out if we need to service it at some time in the future. This extra feature also makes it so "Murphy" will have no fun putting a few mis-wires into my work......

Main Gear - we are not leaving anything about this airplane to guess so Jerry pulled off the main leg fairings and surprise:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture256.aspx

As expected we found surface rust and some places that had chafed through. I guess the Duct Tape (Approved Cessna Part #?) did not do its job. Not a problem, we cleaned everything up, painted it and put real "Clear" Anti-Chafe material. We also patched up the fairings where they were taking a beating. Here is a completed shot of the main gear prior to putting the fairing back on:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture257.aspx

The fairings were put back on with all new hardware and clamps for the brake lines. We still need to pull off the nose strut and clean it up as well.

Cowl Seal - The original seal was asbestos and worn and broken. Jerry riveted a new seal on and it looks great:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture258.aspx

Glove Box - The glove box was cleaned, painted and installed. On top we fabricated a bracket to install some goodies. Since the right side of the panel is completely open we are using this area for our antenna splitters, lighting bus bars, etc. Here is a shot where you can see that all the antenna cables are complete including nice markers, the splitters are installed and the wire harness is taking shape. Once the lighting bus bar gets installed, the shunt for the ammeter gets installed and the radio rack goes in we will clean this up and clamp it all down:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture259.aspx

Note that the bracket along the right wall is where the dimming regulator assembly will go. We were able to use the new dimming assembly from the SP so we will have 4 dimming circuits as follows:

• LED Glare Shield
• Radio Rack
• Instrument Lights
• LED Fuel Qty Indicator

Rear Audio - The rear audio wires have been laced in waiting on the interior to complete. This is the right rear side and it will have a Music 2 input which allows the rear passengers to plug in an MP3 player and listen to their own music. This music input is isolated from the pilot and co-pilot which makes it really nice if you have kids in the back.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture260.aspx

Some Other Things - We installed most of the inspection covers, even the 2 courtesy lights under the wings which have been wired up and work great...

We still have some things to do but the light at the end of the tunnel is very bright now. The airplane looks like a real airplane again. When we did our run-up a few weeks ago we had a few squawks that we had to nail down as well. One was the oil pressure which was pegged to the top during the run-up. Turns out that the pressure transducer is bad so we have ordered a new one. We also had high vacuum and still need to adjust that next time out.

Authors Note -- Someone asked me today what real problems did we find?

Now I know I have poked a little fun at this airplane but considering that it has served its owners happily for the last 35 years the issues we found were nothing and totally expected for an airplane of this age. My original assessment of the plane was that it was a solid low time airplane that needed to be pulled apart and built back up again. I was smack on. This airplane had very little corrosion and she cleans up nice. We have pulled apart everything and replaced every bolt and nut that was worn or corroded. I am fairly confident that the paint shop will really like us for prepping it so nice. When she comes back from paint it will be a "New" airplane and something we all will be proud to fly.

All for now.........

Run up - Instrument Checks Completed

Well I have to say what a blast it has been working this past week on the Cessna with Jerry. We got a lot of the heavy work completed and should have her flying in the next few weeks. The paint is now scheduled for February 15th so we will have some time to fly around before sending her to paint.

Just a reminder -- this shoud be the "better than new" Cessna with most all parts new or completely rebuilt. Here is a picture of the instrument panel (pilot's side) as received back in September ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture161.aspx

And here is how the instrument panel (pilot's side) looks when we went home tonight ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture244.aspx

WOW!

Note that we were able to get the standard "6-pack" configuration of flight instruments in the right place but had to set the gyros up a little to clear the yoke. This while not impossible - did present some problems with sheet metal. Also note the radio rack shelf. This is bolted to the rear and gives the ability to slide the complete radio rack in as an assembly. This will really help if we need to pull it out for a wire modification later. The red cable harness on the right is the main power feed to the radio rack. This will just plug into the rack when it gets installed next weekend.

The instrument panel needed to be modified in 2 areas. Both were non-structural but did require some fancy sheet metal work by Jerry. The first area was a dog house to allow for room at the back of the Attitude Gyro. Because we moved this up on the panel, and we did not want to increase the height of the entire panel, we needed some extra space so we could clear the back of the gyro and allow us to connect the vacuum hoses. Here are a few shots of the completed dog house ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture245.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture246.aspx

The other area was on the right side. The older style Cessna 172 has a drop in the panel as seen here ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture160.aspx

The newer style Cessna 172 is straight across and since we wanted to use the new LED glareshield, we needed to modify the top of the panel. Here are a few shots of the completed panel sheet metal ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture247.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture248.aspx

With all the modifications done and the panel and radio rack fit we pulled everything back out and cleaned up the entire area. We then installed black leather over the top of the instrument panel and fit the original Cessna hardware. This now looks like it came out of the factory. Here are some shots of the leather cover glued in place ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture250.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture251.aspx

We glued the right side down one night and then came back the next day to glue the other side. The thought was if the one (flat) side was secure we could streach it a little to help cover the odd shape of the dog house. It worked although the trimming on the bottom was a little off. This was not a problem because the windshield covered that area.

We installed the windshield with new felt, sealant and stainless hardware. It went in without too much trouble and looks great. On Sunday (12/31) we rushed to push the airplane out of the hangar and do a ground run. The engine started up right away and ran great. We performed a leak check (nothing) and ran her for about 15 minutes. All systems worked great with some minor adjustments needed to idle speed, vacuum pressure and oil pressure.

Today we had a great day of "Rain" so we were able to push her outside for another ground run and leak check, this time water. When I first pulled the plane apart we had water in the belly so we knew we had a leak just not sure where. Here is a picture outside ---->

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture252.aspx

As suspected we found a leak (small one) on the rear window. Jerry pulled out some sealant and applied more. We will check this another day with the hose to confirm we are weather tight before installing the interior. I know --- the nose strut is low. I have a rebuild kit and it is on the list to pull the nose gear off to clean paint and rebuild. We already did the shimmy dampner which was completely empty... a common Cessna problem. Not sure why since there are only 2 seals and the cost about 25 cents to buy new ones.

Here is a shot of N19662 back in the hangar - she looks like an airplane again.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture254.aspx

The Stearman was moved to the back of the hangar so we could move the 172 in and out easy. As the day progressed the temperature went up and I think we have 60 degrees forecasted for later this week. January and I do not think the Stearman is going to be packed away just yet......

Oh yes - here is a picture of Jerry Brooks standing next to his work. He has done a lot of great work helping me on this airplane and it shows. ---- Thank Jerry!

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture253.aspx

All said we had a great week. The airplane is running again and we are very close to flying. I will complete the radio rack this week and install it next weekend. At that point we will only have a few things to wrap up before we can test fly her........

The Instrument Panel goes in.....

The new panel finally came out of the machine shop last Friday and we installed it with all the instruments this weekend ----

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture242.aspx

Because we shoved the DG and AI up enough to clear the control yoke we ran into a clearance issue with the vacuum hoses. We ended up cutting the top of the instrument panel cover and making a dog house to give us some extra clearance. I will put some pictures up once it is finished. The panel fit went well and we have pulled it back out to complete the vacuum plumbing, the pitot/static plumbing and the lighting. Once the rest of the metal cutting is complete the panel will go in and stay in.

Since we have some time off this week from out "Real" jobs the plane is getting a lot of attention. We are almoust done building a radio rack that will allow the complete radio package to be removed from the aircraft as a unit. This will save a lot of work later if we need to add a wire to one of the radio connectors.

We have also added a carb ice probe to the carburetor that will connect up to the EDM-700 graphic engine analyzer, a nice feature.

Starting to make some progress

Well, it has been a few weeks. The rebuilt flight instruments (Alt, VS and Turn Coordinator) took forever from the instrument shop. I did not want to release the new instrument panel until we got these and confirmed that we had the right measurements. Measure twice and cut once was what my dad used to say. Anyway progress has been slowed because of the delay in the panel.

I have been building the radio rack at home in the basement. The instrument panel is coming from the machine shop tomorrow and I have the week off between Christmas and New Years. I have moved the paint back to 2/15 just to give us a little cushion to fly the plane around before sending it off to paint.

The rear avionics tray is back in with modifications to make it stronger. A new ELT has replaced the side mounted system that was in the airplane from the factory. This ELT has a remote head on the instrument panel so you can check activation without tunning the radio and you can check operation without pulling the unit out.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture223.aspx

The GPS antenna has also been installed over the cockpit area which is standard on the new Cessnas. We put a cover over the old Loran antenna in the tailcone which could be used someday for XM weather, etc. We also ran extra wires up to the MFD for this option in the future. Someone will be very happy if they go to install the system and found the aircraft pre-wired. The original OAT probe in the Cessna which is mounted in the air vent has been replaced with a Davtron M803 digital OAT. You can see the new OAT probe and GPS antenna here:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture224.aspx

We have also installed a backup vacuum system by Precise Flight, Inc. which has a shuttle valve that can be pulled from the cockpit. This valve will route manifold pressure to the vacuum instruments. A very simple design but a nice feature for IFR. We will also run the "Low Vac" warning to the master caution panel. The original "L" model had only one warning light - the over voltage light. With this new setup we will have a new Cessna master caution panel that displays Voltage, Low Oil Pressure, Low Vacuum and Low fuel -- very nice.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture222.aspx

You might also notice in this picture that the battery box and relays have been pulled off, cleaned and painted.

The single EGT instrument has also been replaced with a nice JPI EDM-700 Graphical Engine Analyzer. This will show CHT and EGT for all cylinders. It also has a carb temp probe which will be very nice to alert us to possible carburetor icing. Here is a picture of the probes installed. This aircraft had a nice Tannis heater and we wanted to keep it. Fortunately JPI had special probes for the cylinder temp that could be installed under the Tannis probes.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture221.aspx

Anyway, when the instrument panel shows up tomorrow things will start to take shape fast. Please watch for more posts......

Pilot Window - Antenna Cable and the new Fuel Qty Indicator

We did not get a lot of work done again this weekend because we were still working on painting at the airport. I can see the end of that tunnel so hopefully we will start making real progress on the Cessna soon.

We did complete the final (for the 5th time) measurements on the new instrument panel. My dad always said "measure twice and cut once" so hopefully the panel will be perfect when it is complete. We are waiting on the rebuilt Altimeter, VSI and Turn Coordinator to make sure we have the cutouts perfect and if so we will fire off the CAD file to the machine shop.

Jerry completed the pilot side bubble window. I have to say that the view from the front with the 2 bubbles is impressive. I cannot wait to see how she flies with them. Here is a shot of the pilot side window:

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture199.aspx

We also pulled new RG400 antenna cable from the instrument panel into the tailcone. The Nav antenna on the tail is connected waiting to be dressed to the new radios. The Marker Beacon and the Transponder need to be dressed in as can be seen in the following picture. I also sent 2 spare 4-conductor cables from the front to the back. I may be crazy but if someone wants to put in weather datalink they will thank me for making their job simple......

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture200.aspx

This week we also wired the Aerospace Logic TSO'd fuel quantity indicator and powered it up. This is a replacement for the original Cessna gauges. I would have been happy using the R or S style fuel qty indicator but they were setup for 26 gallon tanks and mine is only 19 gallons. This will fit in the small round hole to the left of the pilot yoke and should look great. We still need to properly calibrate it by draining each tank and then adding fuel 1 gallon at a time until full.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture201.aspx

New Main Circuit Breaker Panel Installed and Working

With all the electrics torn down to basics, getting the main circuit panel installed and working was a big milestone.

Here is the old panel. Note the breakers and rocker switches which were common on all the Cessna models until they came out with the new single engine line in 1997.

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture152.aspx

An interesting thing about the way Cessna (and many others) did their electric back then. That really big breaker (in this case 60amp) means that there is a hot side of the breaker unprotected inside the panel. This 8 awg wire of course can be switched off with the master switch but while the master switch is on there is a 60 amp power source coming in unprotected.

The new aircraft have dual essential power busses with breakers in an electrical box on the firewall near the battery. The only battery / alternator related breaker inside is the alternator field breaker which just supplies power to the field side of the regulator.

Anyway I thought it too big of a jump to redesign the original electrics in the aircraft so I put the 60 amp breaker back on the panel. I also tied the 2 essential busses together (you can see the bus bar jumper) so there was one essential bus identical to the original design. The 2 areas that did get changed for the better were the loss of seperate switches and the dual avionics busses.

On the original design there was a relay that would cut off power to the avionics bus when the starter was energized. While this is good, there can still be voltage spikes on the line when the engine shuts down which is the main reason they all went to an avionics master switch. On this new panel I have 2 - 20 amp breakers that then go through the split rocker switch to power 2 avionics busses - way cool and the way it should be.

Also the new design uses switch breakers and I incorporated them to eliminate the need to have a breaker and switch like the original design.

Here are a couple of pictures of the power panel front and rear -

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture182.aspx

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture183.aspx

And here is what the panel looks like now with all the basic electrics operating -

http://mansfieldlanding.com/forum/photos/1972_cessna_172l_restoration_n19662/picture184.aspx