Austers on Floats

[shorty]

A question which should be right up Anthony's or Baz"s alley. When the Austers NZ 1701 and NZ 1705 were on floats they used a different fin and rudder assembly from when they were on wheels. On floats the rudders used aerodynamic balancing whereas when on wheels a mass balance was used. How much of a task would it have been to change these over? Is the fin to fuselage fairing just a simple metal fairing attached with screws? I assume that the ventral fin would have had a similar set-up (if it used a fairing at all)

[baz62]

The fins and rudder are quite different Shorty and no fairing as the fabric provides the blending of the fin into the fuselage. The small tail verizon curved rearwards at the top to line up with the top of the rudder. The bigger fin/rudder combo has the fin with a flat top so the top balanced part of the rudder can sit above. And not an easy job to change the fin as the fabric goes over it to the top of the fuselage. So if you go large to small you still need to remove the fin fabric (or possibly peel it away partially as the leading edge of the big fin goes further forward on top of the fuselage and is tied to a fuselage tube (whereas the small fin isn't.)
If it was me once I had the big fin and rudder on it would stay on as it gives you a bit more rudder authority and less hassle to go back again!.
This is from the repair manual and shows the big style fin being covered first before the fuselage. (This is a high back Auster like a J5G but fin is the same)
Scan0001 by Barry Tod, on Flickr


And two Austers showing the two types, with the smaller rudder using the "weight on a pole" for rudder mass balance.

Small
Auster_AOP.6_TW539_663_Sqn_1954 by Barry Tod, on Flickr


Big
1920px-Auster_J1N_Alpha_VH-PCY_Berwick_Vic_03.88 by Barry Tod, on Flickr

[shorty]

Thanks for that Baz, so changing from wheels to floats and back again wasnt a very simple quick task . It wasn't obvious from the photos how the fin was faired.
P.S. I like the way the article come from a web page called "fighter plane blueprints"!

[baz62]

Jan 12, 2019 10:56:38 GMT 12 shorty said:

P.S. I like the way the article come from a web page called "fighter plane blueprints"!

Yes they do reprints of quite a few manuals but yes bit of a stretch calling an Auster a Fighter!