AUDAX

[Bloodhound]

I took a few pictures at the flying field today. The weather was really bad: overcast, cold, windy, and even a slight drizzle from time to time. But flying was great

[Bloodhound]

I initially planned to have the fuselage painted by a professional, but he became busy with other projects so i decided to film cover the fuselage.
I started by cutting the cardboard templates and sanding the fuselage with 300 grit sandpaper:


The first color applied was white, followed by the other colors:


I had to give up on the gold color used on the wings because when applied to the fuselage sides, from most angles and in most lighting conditions it looked more like dark brown. It also highlighted too much the areas where it overlapped the other colors, so i chose to use a light grey instead.


The canopy will be painted later, for now it is just sprayed with primer.
Some images of the finished covering job:

[fabien drouet]

I'm very surprised by filming a moulded fuselage. I've never seen before.
It would be very light ?

[Bloodhound]

You are right Fabien, filming a composite fuselage is not common practice. I prefer paint, but i can't do it myself so i had no choice but film cover.
I didn't weigh the fuselage before, so i can't tell exactly how much the film weighs. The film for the wings weighs aprox. 50g for each wing panel, so based on this the film for the fuselage is probably around 110-120g.

[claudecuinet]

Hello Alex

I think it's lighter, may be around 60 g.
Area of fuse is around 1 m2 (I measured on Harmonie fuse which is bigger than Audax) and 1 m2 Oracover weights 60 g.
Je pense que c'est plus léger, autour de 60 g.
La surface du fuselage est environ 1 m2 (j'ai mesuré celui de l'Harmonie qui est plus gros que celui de l'Audax) et 1m2 Oracover pèse 60 g.

So how do you did to avoid bubbles ?
comment avez vous fait pour éviter les bulles ?

Your design is awesome.
A+

[Bloodhound]

Thank you Claude!

Not all colors are the same weight, for example the white film weighs 89g/m2. Here's a link to the weight table from the Oracover web site: http://www.oracover.de/downloads2/daten ... e_engl.pdf

The fuselage side area is a little larger than the wing. Total weight gain for the wings after film covering was 100g; the fuselage uses the same colors (except grey) so the film probably weighs around 110-120g.

To avoid the bubbles i started with low temperature (100-110 degrees C, measured with an infrared thermometer on the sock covered iron).This is enough to activate the adhesive without any shrinkage of the film. I always kept the film tensioned and tight on the fuselage with one hand and worked my way from the center to the extremities to avoid trapping air under the film. In the end i used a slightly higher temperature (130-140 degrees C) and went over the whole surface of the film one more time.

If you use 130-140 degrees right from the start, you will create gas bubbles between the film and the fuselage surface. Anyway, gas bubbles can be cut with a razor down the center to let the gas escape and you can go over them with the hot iron one more time.

[Bloodhound]

The rudder i built last year was cut and modified at the field for testing purposes, so i had to build a new one:


Film covered wheelpants:


The spinner was painted red matching the fuselage film cover and the canopy was painted using a light blue metallic color:


A few images of the assembled fuselage:

[Bloodhound]

Decals were added to the wings and fuselage:


A few images of the assembled model:

[fabien drouet]

Very nice, you could be proud of your job

[Bloodhound]

Thank you very much Fabien !

[Bloodhound]

Setting the incidence angles with the TLL-90S angle meter.
I measured all incidences 4 times and repeatability is very good (approx. 0.005 - 0.007 degrees for the wings). Elevators are clamped in neutral position only at the stab tip and they flex a little under the weight of the angle meter and bar, so variation in measurements is a little larger (around 0.01 - 0.02 degrees).

[Bloodhound]

And finally some pictures from the flying field:

[Bloodhound]

Picture from the Hungarian F3A Cup in Gyor:


Video of the Audax F3A going through some of the P17 maneuvers.
We tried to make a video of the whole P17 schedule but the cameraman couldn't follow the plane all the way through. This is all i could gather from the raw video: