3m car wrap film on fuselage

[Fendermandan]

Friend of mine sent his plane to be repainted and made me think of an idea if the plane is stripped to aluminium and all shined up to add some of that 3m wrap to add design details instead of painting. Later he would take it off and make something new easily. I dunno how heavy is that film and if would substantially mess with basic weight.

[ScudRunner-d95]

Probably would need to an approval type thing from the feds to make it Kosher, homebuilt you might be good. don't know just throwing out my brain tinking.

[woodzi]

There are some using it on homebuilts. There is an article in a recent EAA magazine about it.

[Chris]

http://www.eaavideo.org/video.aspx?v=5222132662001


There don't seem to be any regulatory issues - Scheme Designers does vinyl designs for Cirrus, etc. Seems like the more typical approach for owners is to spray a base coat and apply stick-on designs over that. I believe the Red Bull guys and other who use a lot of flashy sponsor stuff do full wraps though, makes it easier to update your scheme.


With aluminum planes one thing to keep in mind is that wraps are not terribly happy conforming to lots of little details - think dome head rivets. Not impossible but you definitely need the right person doing the job.

[Colonel]

Not sure anyone gives a shit about the engineering
side of things, but putting wrap on flight controls,
you probably want to worry about balance.

I know homebuilts are great, homebuilts are wonderful
because they don't need any paper, but a guy two
hangars down from me - Andy Philips - is still dead
because his rudder fluttered on his RV-7 after an
auto mechanic slathered on the bondo.  Legally,
of course.  The paper was fine, because you can
do anything with a homebuilt.

We had a nice funeral for him.

[img][/img]

I'm happy to have a nice funeral for you guys, too,
that worry more about the paper than the engineering.

Not everything is a "learning experience".  At least,
I'm not sure how much Andy learned from that, after
his rudder exploded.

Not sure anyone remembers Steve Wittman, either.

Remember, there will be no new causes of aircraft
accidents in 2017.  Feel free to relive the past.  We'll
have a nice ceremony for you.

[John Swallow]

“…but a guy two hangars down from me is still dead because his rudder fluttered on his RV-7 after an auto mechanic slathered on the bondo.  Legally, of course.  The paper was fine, because you can do anything with a homebuilt. “

Not according to the accident report...

It would appear that flutter was the cause of the accident alright, but not particularly due to the “bondo”.  Excessive speed, “g” loading, and the lack of a post painting W & B appear to have contributed to the accident.

Amateur-built, home-built – call them what you will, must be maintained IAC recognized standards for such aircraft.  If you change/modify them without proper oversight, you become a test pilot – an inexperienced and poorly paid one at that…

The findings from the accident report:  (a link to the report follows)

Findings as to Causes and Contributing Factors

1. After painting, the rudder was not likely balanced, nor the aircraft reweighed. As a result, the rudder was susceptible to flutter at a lower speed than designed and the aircraft was over the maximum aerobatic gross weight during the manoeuvres.

2. During the manoeuvring sequence, the speed of the aircraft reached 234 knots, exceeding the 124 knot manoeuvring speed and the 200 knot never exceed speed (Vne). 

3. The aircraft encountered either flutter or overstress of some rudder components. Subsequently, the vertical stabilizer and parts of the rudder separated from the empennage during flight. Consequently, the aircraft became uncontrollable resulting in the impact with terrain.

Link to the Report:

http://www.tsb.gc.ca/eng/rapports-repor ... 0o0018.pdf


I built and fly a similar aircraft and I would reflexively loosen my anal sphincter muscle if I ever saw 234 knots on my ASI…

Regarding the "plastic wrap", I'd closely look at the process if ever I built another RV... 

[Colonel]

[quote]but not particularly due to the “bondo”[/quote]

Not sure how you concluded that.

The auto mechanic - who disappeared shortly after -
slathered on the bondo to the rudder aft of the hinge
point, reducing it's flutter speed to an obviously
unacceptable margin above Vne. 

It was supposed to flutter at 300 knots, according to
Vans.  I think there is a significant difference between
300 and 230 knots, even if you don't.

I knew both the mechanic and Andy.  I know exactly
what was done to that aircraft.  It was bondo'd and
painted across from my hangar, reducing the flutter
speed of the rudder to 230 knots.

Yeah, Andy accidentally exceeded Vne.  If the auto
mechanic hadn't put the bondo on, he'd still be alive.
We try to plug the holes in the swiss cheese.

Remember, Vne is 90% of Vd.  One of the proud AvCan
experts likes to post pictures of his dashboard, well
past Vne.  Airspeed indicators and pitot/static systems
can have wild errors, too.

If you think it's a great idea to put bondo on your RV,
go right ahead.  We'll have a nice ceremony for you, too.

You homebuilt guys are really weird.  The locals were
in total denial, and blamed buzzards (in winter?) for
the accident.

I really don't know why the fuck I bother, frankly.

Go kill yourselves.

[cgzro]

The center of gravity of a control surface relative to its hinge line and the stiffness of the hinge control,its flutter speed. Andy is 100% correct. just because the report does not mention bondo the fact of repainting and not balancing is essentially saying the same thing.


If you put stuff on a control surface you need to check that  surface is still in the weight and balance as designed and tested during the engineering/test phase of the ac otherwise you are a test pilot and should be wearing a chute etc.

[DeflectionShot]

First time I've heard that people use Bondo on airplanes. Is that a common practice for homebuilts?

[Slick Goodlin]

[quote author=DeflectionShot link=topic=5439.msg14065#msg14065 date=1484850354]
First time I've heard that people use Bondo on airplanes. Is that a common practice for homebuilts?
[/quote]
There's some speculation that Bondo may have [i]started[/i] with airplanes.  To maintain laminar flow, P-51s had their wing surfaces faired in with surface putty right from the factory.  The couple of time capsule examples of the type (ie. never restored) show that the fairing compound is about the same colour and consistency as Bondo, a product that showed up shortly after the second world war.


[quote author=cgzro link=topic=5439.msg14063#msg14063 date=1484849196]
The center of gravity of a control surface relative to its hinge line and the stiffness of the hinge control,its flutter speed...  the fact of repainting and not balancing is essentially saying the same thing.

If you put stuff on a control surface you need to check that  surface is still in the weight and balance as designed and tested during the engineering/test phase of the ac otherwise you are a test pilot and should be wearing a chute etc.
[/quote]
Even test pilots don't want surfaces out of balance.  Take the Skystreak for example, one of those experimental push-the-envelope machines of the late forties.  Douglas delivered it in high-visibility red, then at some later time NACA had it repainted to white.  The thing is, they left the control surfaces red because they had been balanced that way and NACA didn't want to re-balance them after a coat of white paint.
[img width=500 height=375]http://www.fiddlersgreen.net/aircraft/D ... -pilot.jpg[/img]
[img width=500 height=375]http://aircraftwalkaround.hobbyvista.co ... 58ch02.jpg[/img]