National Aeronca Association Bulletin Board

I am picking up my L3 project in a couple of weeks and I'm busy gathering as much information as I can about this model. I orders about $150 worth of manuals, catalogs and drawings etc so far.

My question concerns this:

According to the Type Certificate A-751 the gross weight for an L3-B (O-58B) is 1260lbs.

In the Army Air Force "Handbook of Operation and Flight Instructions" it gives the gross weight as 1260 lbs - but on the last page, Section V, the weight data given lists the gross weight as 1300 lbs.

Also, in the Army maintenance and erection manual it states the tire pressure for a gross weight of 1300 lbs, also.

While my project has logs, they are skimpy and I don't remember seeing a gross weight figure.

I come from a homebuilt background and dealing with FAA stuff such as 337s and STCs is new to me but:

Given that this model of airplane, in some forms, has obviously been operated at 1300 lbs (and even 1350 lbs, in the case of the SO-58B) would it be possible to somehow legally increase the gross weight to 1300 ? Would such a step require something more drastic than a 337? I also intend to change the A-65 to A-75 configuration (possibly even A-80?) - can this be done with a 337 and an increase in gross to 1300lbs included at the same time?

It's only 40 lbs, but that is a big chunk of weight in the real world. The difference between flying with two big guys or not flying at all (legally).

Lots to learn and I can't wait to get this home to my shop.

It looks like the TCDS has the 1260 number as the max gross weight. If you can find a military document that allows the higher weight it could be used as approved data to allow the increase.
Make sure it was a plane contracted with the military and not a civilian plane pressed into service during the war.
Paul

Aerco,

First off, a first name would be nice, we are a friendly group here. As well you get more replies with a name.

Third I have to scold you a bit. Darn, wish you had posted here before doing the above. Please do not order any more things like manuals and such as frankly its all available on the internet for FREE! As well there was no manual for any of the Aeronca's before the L-16A and Sedan models. Its all contained in the Type Certificate Data Sheet and thats available for free at various places on the internet.

Now, lets help a bit. Go to http://www.aeronca.com and take a look there. This is Todd Trainors excellent Aeronca site and has 337's, STC's, manuals and so on for FREE downloading. He also has a very good selection of Aeronca factory blueprints. What he does not have, we at the NAA have and will email them out for free.

Next is: http://hangar9aeroworks.com/11ACmain.html This is John Bakers excellent site that has a lot of very useful info on Aeronca's.

Enjoy your airplane and when you have questions, please feel free to ask!

Joe A

Ah - sorry - my name is Peter; I'm in Corona CA.

I believe I have scraped up everything free about the L3 there is to find, but ordered some things like part catalogs from Essco. Even if I duplicate some stuff, you can never have enough of this kind of thing. I collect old aircraft engineering books and actually found a few references to the L3 in there too.

The airplane was built in May 1942, so it was not a civilian version, I would assume. All the reference material I have found so far refers only to military models. I intend to keep it as original as possible, but also as light as I can get it. I am NOT going to search the country to find original radios to install (although that would be oh-so-cool...)

I think I have a valid case for the 1300 lbs gross weight - the last revision of the military operating manual (Technical Order N0. 01-145LA-1) definitely lists the weights as:

empty - 870,
useful load - 430,
fuel and oil - 80,
misc equip. - 10,
gross weight - 1300.

Wing loading listed as 8.23 lbs/sq.ft and power loading as 20lbs/hp, all of which fits.

Empty weight figures for the L3B without all the military stuff (radios, battery, generator) is listed at 782lbs, leaving 518 lbs useful. Now that is a figure I could live with happily for this type of airplane, unlike the brand new Champ which has a useful load of only 395lbs! Not much of a two-seater....

Peter,
It does look good for a GW increase with the information you have. Check your logs to be sure of the model. My TAC was built Feb.7,1942, Aeronca filled all of their order backlog before they started the L birds. Most of the planes were delivered to the CPT program and sold as surpluss assets after the war.
Paul

Peter,

See if you can get the CD from the FAA that lists the aircraft's history. My L-3 came w/ copies of all Bills of Sale since it was sold as surplus. The bill of sale where the RFC sold it to its first civillian owner was also included. This showed its military identification number and with the help of members of this forum, I was able to get my L-3s service record.

L3CFI wrote:Peter,

See if you can get the CD from the FAA that lists the aircraft's history. My L-3 came w/ copies of all Bills of Sale since it was sold as surplus. The bill of sale where the RFC sold it to its first civillian owner was also included. This showed its military identification number and with the help of members of this forum, I was able to get my L-3s service record.

I received the CD from the FAA and it does not show anything more than I have in the paper records, though.

The Bill of sale list the details as:

Aeronca L3B

Manufacturer's Serial No. 058B2042

Identification Lot: 42-36178 (is that an individual aircraft's number, or just for a lot?)

The data plate lists date of manufacture: 5-2-42

Those are all the numbers I can find on the airplane or paperwork so far.

All sold for the princely sum of $303.60 in 1945

Its civilian registration was N4641V.

Am really surprised that you have paper records for most of its life.

Personally that would make me feel that its worth more than many as the majority of the WW2 airplanes were grabbed by the military and when returned none of the previous logs or paperwork ever made it back with them.

Joe A

Peter,
The Identification Lot number will be the military serial number. You can use this number to get the military record card. It will show where it was stationed and any major repair visits. I posted how to request it somewhere in the site.
I'd like to take a look at it on my next trip to Corona.
Paul

Paul Agaliotis wrote:Peter,
The Identification Lot number will be the military serial number. You can use this number to get the military record card. It will show where it was stationed and any major repair visits. I posted how to request it somewhere in the site.
I'd like to take a look at it on my next trip to Corona.
Paul

I'll do some digging into its history.

You're welcome to stop by anytime; I'm at shop every weekday and some weekends too. Just drop me a line when you want to visit.

Well, I've a question on this also. In more than one place that seem to be authoritative sources in other aspects, I've seen the gross listed at 1800 lbs, usually for the O-58B/L-3B, but also heavy weights for other variants as well. I have a hard visualizing such a plane with 65 HP getting up in the air at that 1800, unless it has a B-29 sized runway and a really stiff headwind.

I know all about "war emergency ratings" and the like, but 1800 seems so... wrong...

Is the 1260 (or 1300) figure the gross for all military spec O-58/L-3 types? That one seems to make the most sense...

Dennis,
The T series G/W is listed as 1150lbs and the TA series is 1200lbs. These weights are listed in TCDS A728. The O-58B is listed at 1260lbs on TCDS A751.
Paul

Dennis ,
I've also seen 1800 lbs. listed many times in various places , but I believe it is probably a mistake by someone trying to read an illegible document and seeing 1800 instead of 1300 . Paul is correct with the gross weights he quoted .

The early Flight Ops. Manual , TO-01-145LA-1 for the O-58B / L-3 series , lists the allowable gross weight as 1260 lbs. , the last revision shows the gross weight as 1300 lbs. The FAA Type Certificate Data Sheet ( last revision available ) still shows 1260 lbs.

The Military manuals MIGHT be used as " Acceptable Data " to apply for approval , but is not recognized as " approved " by the FAA .

The 85 HP STC previously sold by Buzz Wagner has the additional advantage of increasing the allowable gross weight of ALL aircraft listed in both the A-728 and A-751 TCDS to 1300 lbs. which is probably as much weight as you would want to subject the airframe to . This might be the preferable way to go since the STC is already " approved data " .

The only down side is that you still have only 12 gals. of fuel . Getting an aux tank approved may be a bigger challenge .