David Lasher's reply to STC weight increase

john-ranger · Post by **john-ranger** » Wed Aug 20, 2008 23:07

Hi John,

You can add aux fuel tanks in the wings or install no bounce oleo's. You will have to install a dorsal fin if you increase your gross weight over 1220 lbs.

Thanks,

David Lasher

=========

If this is true, where can I purchase a dorsal fin????

-John

---------------

Post by **joea** » Wed Aug 20, 2008 23:27

Just saw one on Ebay.

You do know that to do this you have to recover the whole fuselage I hope? This is not a "bolt on job" by any means.

Also Wag-Aero may still sell them.

Joe A

john-ranger · Post by **john-ranger** » Wed Aug 20, 2008 23:58

No. I thought I could recover the tail feathers only...Oh well.

Post by **joea** » Thu Aug 21, 2008 00:04

The bigger tail is accomplished by bolting a piece on the top of the fuselage that goes to the top of the tail, thus giving you a larger cross section.

Do not know of any way to do this safely and legally without recovering the entire fuselage.

Post by **joea** » Thu Aug 21, 2008 18:10

John,

Just thought of something. If you want to buy the pieces to make your airplane a large tail version, bet that ACA (American Champion Aircraft) would still make them.

Joe

Captgrumps · Post by **Captgrumps** » Fri Aug 22, 2008 00:34

Univair has the dorsal bolt on--it is their P/N 7-792. Guess it will cost between $350 and $400 . Check with them at 1-888-433-5433.

Doug

jerrymjr · Post by **jerrymjr** » Fri Aug 22, 2008 09:43

We dont stock the Dorsal, but I have seen a dozen or so go out over the years.

Its really a matter of perspective on directional stability with or without the extra area. Personally, I think it was a means for Aeronca to pay for engineering the mod. Also, discourages people from doing it and just get them to buy a new 7DC or EC.

Captgrumps · Post by **Captgrumps** » Fri Aug 22, 2008 12:54

Got a friend with a Champ with Wagner 0-200 STC installation and he won't fly it any distance. He says the small tail with the 0-200 is like a fish swimming through water--good exercise for the legs though. Says he wishes it had the dorsal.

Doug

john-ranger · Post by **john-ranger** » Sun Aug 24, 2008 23:18

I guess I'll wait until I recover.

Jerry Eichenberger · Post by **Jerry Eichenberger** » Mon Aug 25, 2008 10:18

Doesn't it make sense that if the dorsal were really needed, the new 7EC, with 100 hp, and which as a 1320 gross weight would have it, which it obviously doesn't.

Could this fact be used as the needed approved data to get a 337 to raise gross weight from 1220 to 1300 or 1320 without the big tail?

Seems logical, but then, logic may have little to do with it.

Jerry Jr. - Is the vertical on the new 7EC the same size as the 7AC?