S-1C v S-1D fuselage differences

[gloopy]

[FONT=&quot]In order to resolve a type registration issue over a Pitts S1 I’m trying to research how it’s possible to tell an S-1 fuselage is a ‘C’ or a ‘D’ variant and also to form some view of its likely origin. I’ve read through all the fuselage forum posts and gained the impression that differentiation is a little ‘hit or miss’ as fuselages may have been modified over time.[/FONT]
[FONT=&quot]As a starting point I’ve pulled together the following:[/FONT]
[FONT=&quot]Are there any fundamental differences in construction of a ‘C’ or a ‘D’? For example is the tubing of a different wall thickness or does one variant have more tubes than the other?[/FONT]
[FONT=&quot]I think I’m correct in thinking that the ‘D’ is an ‘S’ fuselage fitted with the ‘flat –bottom’ wings and chronologically came after the ‘roundwing’ ‘S’ which was developed after the ‘C’. Was the ‘S’ fuselage simply a late type ‘C’ or was it changed in any way specifically for the ‘S’? Is the ‘D’ fuselage exactly the same as an ‘S’ built to the Aviat plans?[/FONT]
[FONT=&quot]The differences I’ve identified between ‘C’ and ‘D’ type fuselages include:[/FONT]
[FONT=&quot]Pitch trim. The ‘D’ has adjustable pitch trim whereas the ‘C’ does not although some may have been retrofitted. Thus all ‘D’s have weldments for a trim system and trim cable housing.[/FONT]
[FONT=&quot]Elevator hinges. The ‘D’ uses ‘strap’ type elevator hinges rather than piano type hinges of the ‘C’. Again some ‘C’s may have been retrofitted.[/FONT]
[FONT=&quot]Fuselage length. The ‘D’ fuselage is 3” longer than the ‘C’ fuselage although later ‘C’s also had this lengthened fuselage.[/FONT]
[FONT=&quot]Elevator idler bearing. ‘D’s have an idler bearing midpoint in the rear fuselage whereas ‘C’’s don’t have this.[/FONT]
[FONT=&quot]Brace at top of cabanes. Not sure about this as to whether there’s any difference?[/FONT]
[FONT=&quot]Are there any other distinguishing features between ‘D’ and ‘C’ fuselages?[/FONT]
[FONT=&quot]Is it possible to distinguish a factory built fuselage frame from a homebuilt frame i.e. by the quality of the welding?[/FONT]
[FONT=&quot]I’d be very grateful for any input, corrections to the above.

Thanks to all in advance
[/FONT]

 

[smutny]

 

[jrs14855]

 

[cwilliamrose]

 

[acropilotbret]

 

[TFF1]

 

[gloopy]

 

[PittsDriver68]

 

[TFF1]

 

[Morphewb]

 

[jrs14855]

 

[gloopy]