Ercoupe 415-C 9CF Baggage Compartement STC and 1320lb Gross Weight STC

The trim tab upgrade is a piece of cake.

The existing trim tab (really just a long piece of piano hinge) stays right where it is, you don't even need to disconnect the cable.

The new trim tab is just a long aluminum strip that gets riveted to the existing tab to extend it. You just need a drill and a rivet squeezer. I got a used one from Vernon, clamped it to the existing tab (which becomes the hinge), match drilled the existing holes, and riveted it on.

The new trim tab is so much more effective that I now only use about one inch of "throw" in the center of the trim control. I feel better about having a lot more excess trim authority - it would be much more feasible now to land the plane if I somehow lost an elevator cable.

I can get you some photos of the new tab if you would like them. If you end up buying the Univair version, I'm not sure it's pre drilled but again, no biggie. The instructions are probably (but don't take this as gospel) something like "drill a rivet hole every 1.5 inches" because it really is a simple upgrade. 

The below is from the Ercoupe Tech Note that covers elevator trim tabs. I can only find in it that if you have a C85 then you go to the 1 3/8" trim tab. Else if you have the C75 it is the 3/4" trim tab. Mine sticks out a little bit from the elevator trailing edge so I'll have to measure mine. I'll defer to Ronald or Brooks.

Elevator Tech Note:
dyzz9obi78pm5.cloudfront.net/app/image/i...rcoupe-tech-note.pdf

Thank you guys for the feedback and suggestions, It looks like a good way forward it to see if Vernon has a pre-made cargo compartment i can install to save some time.
To answer your question Ronald, converting to a 415-D seemed like more work than it was worth. 
Allong with the weight increase stc and baggage compartment, I am also installing a earth-X battery so by the end of these upgrades my useful load should be around 450lbs. 
I didnt see any specific requirments to limit the elevator travel for the 1320# stc either and I am feeling like I am missing something 

Brooks, thank you for the detailed post! This is great and really makes this project feel more doable. I hope that people in the future with similar questions see your post. 

Additional question, is there a general guide on replacing the narrow trim tab with the 1 3/8" tab?  
 

After reading the description of required modifications for the 1320 STC (Alpha Aviation), I don't see any requirement to adjust the elevator travel. It appears you keep the 13 degree up limit of the 415C. This STC only existed because of the Light Sport eligibility weight limit of 1320#. Due to recent changes, that limit is now much higher. Have you considered just converting to a 415D and getting the 1400# limit? (that does require a 9 degree up elevator limit).

If anyone sees that I am incorrect on any of this please correct me.

Similar to what Brooks was saying on the baggage area, Alpha Aviation also has the 1320 STC and it has a PDF you can read over. Looks like a slightly bigger trim tab and limit it to 9° only on the up travel and your bird has to meet certain criteria to be able to use it. (On the PDF)

Point of Interest if you have time and money, you can upgrade your 415-C to a 415-D model which increases the max weight to 1400 lbs: www.univair.com/content/ERC_IL01.pdf

Ronald Raty talks about this here but that is EXPENSIVE. Requires rebuilding parts of the aircraft to reinforce things and you strictly follow the 787 and submit a 337: ercoupe.org/index.php/forum/general/344-c-to-d-upgrade.

Forum discussion on this topic with @larrysnyder: www.ercoupe.org/index.php/forums/non-tec...ons/1200-1320-lb-stc

Here's the link to the STC and kit for it: www.aircraftspruce.com/catalog/appages/ercoupe05-15054.php

STC PDF Overview: www.aircraftspruce.com/catalog/pdf/ERCOUPESTC.pdf

Hi Brandyn,

I have just the small cloth baggage area but I do have the 1320 STC, let me read that over and get back to you with what I find on it tomorrow else I defer to the awesome folks here who are far more knowledgeable than I on all things 'Coupe.

Meanwhile look over the sister Ercoupe site, I think Vern runs this site?
Ercoupers repair pages:
www.ercoupe.info/pmwiki.php/Main/InteriorInstallation
www.ercoupe.info/pmwiki.php/Main/InteriorInstallation-06