Increased Gross Weight - Wood Spar Decathlons

Joined
May 6, 2020
Messages
7
Hey everyone,

Does anyone know of an Increased Gross Weight kit that's available for the Wood Spar Decathlons and Super Decathlons? I know you can 'upgrade' a Decathlon to the 'new' standard as per A21CE with metal wings, extended gear and the 180 HP (360) engine and have a 1950lbs Normal Category.

Also does anyone know if the fuesalage primary structure has been changed over the years? Especially around the landing gear?

Thanks!
Hugh
 

Bartman

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Staff member
Joined
Mar 27, 2018
Messages
1,122
Location
New Jersey, USA
Hugh,

The gross weight increase comes from the new wings so there aren't any options to get that with wood spars, AFAIK. The metal spar STC is for Citabria/Champ airframes only so there's no STC path to metal spars and even then, the Milman metal spars don't provide for a gross weight increase.

Primary structure is basically the same but there have been small changes. I'll have a bare frame back home sometime soon and I'll post photos when it's here. There have been some gussets added to reinforce tubing clusters but nothing structural beyond that that I'm aware of. A small diameter tube around the gear leg has been modified but it is only for the purpose of providing an attach point for the fabric where the leg passes through the fabric.

Hope that helps,
Bart
 

Bob Turner

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Joined
Apr 4, 2018
Messages
759
Just be careful and have good paperwork on board. The airplane will lift almost anything you can get in it.

When I put the Greek in back (she weighs 115#) I am at gross with full tanks, no baggage. I am not going to tell you I put her 300# brother in law in the back and it leapt off the ground. Nope. Didn’t do that.

Two guys and parachutes means you need to prove the tanks were not full.
 

BB57

Well-known member
Joined
Feb 20, 2020
Messages
45
This comes from an IAC "Technical Tips" publication, page 105:

file:///home/chronos/u-e3fbbe814d5e28e1fa8c738be4443f8432e0dfc7/MyFiles/Downloads/technicaltipsmanualvol1_0.pdf

"Dear Fred,

I have been asked to reply to your request for comparison differences in the Citabria and Decathlon aircraft.
Unlike the Cessna Aerobat, which is basically a beefed up Cessna 150, the Citabria and Decathlon are two different aircraft designed and certified independent of each other. For this reason, it would require a detailed description of both the Citabria and Decathlon fuselage and wing structure to properly describe the differences.
The fuselage of the Decathlon shares much of the same truss design of the Citabria, but structurally it is quite different.
*The material thickness of steel tubing is increased in many areas.
*The tail section has additional truss members.
*The wing attach and carry-through members are stronger.
*The fuselage is designed for 180 HP. The wing of the Decathlon is completely different and shares very few parts with the Citabria.
*The airfoil is a NASA 1412. This, for one thing, distributes flight load differently.
*The main spar is larger (wider and deeper).
*The rib spacing is closer (more ribs per wing).
*The front and rear wing struts are larger and stronger — adding greatly to its compression strength or negative flight loads capability.
The windshield of the Decathlon is made of thicker, stronger material and is supported with a center brace.
Another big difference is in the certification and operating limitations.
The Citabria is approved for aerobatic maneuvers listed on the placard on the panel. Only those maneuvers are approved.
The Decathlon is approved for a list of maneuvers and variations or combinations of those maneuvers which does not exceed the operating limits. Only the tail slide and lomcevak are not approved.
I have enclosed a copy of the Decathlon flight manual and the Citabria owners manual as a reference for you to compare operating limits and approved maneuvers in more detail.

I hope this explanation is adequate. If not, please do not hesitate to contact me. Sincerely, BELLANCA AIRCRAFT CORPORATION Richard M. Johnson Product Manager"