 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
raimo.toivio(at)rwm.fi
Guest
|
 Posted: Fri Aug 03, 2007 4:45 am Post subject: Europa colours /The facts |
 |
|
All
who are interested about "colour & temp" topic:
couple of days ago I promised to come back after
finding some real scientific facts instead of "I feel so
knowledge" and here we are:
I have today interviewed two (2) experts, one after one,
just to be sure:
1) Professor Timo Kalema, Energy and Process Technique,
Tampere University of Technology, Tampere Finland
2) Professor Reijo Karvinen, Energy and Process Technique,
Tampere University of Technology, Tampere Finland
http://www.tut.fi/public/
I strictly point both of these gentlemen represents the highest thermal knowledge:
They BOTH stated as follows:
- direct from the sun the surfaces (Europa upper parts) get SOLAR RADIATION
- the wave lenght is about 1 um
- the colour of the surface is essential because of the thermal absorbtion
- Europas should be painted white or at least light coloured
- that is even more important what nearer equator you are
- from the ground the surfaces (down side parts) get only THERMAL RADIATION
- the wave lenght is about 10-100 um (depending the ground material)
- the colour of the (plane dn side´ s) surface is nothing to do w absobtion of that radiation
- easier observation ratio method:
" go to the shadow and have a white shirt or black shirt on and you still feel same temperature"
I make the point even clearer: two Europas, one has white coloured down side wings
and other one has black coloured down side wings. Both has light coloured upper sides.
Both are standing on the hot black asphalt side by side. If measured the temperature from
the down side surface, it will be exactly same. That is proved and a fact - I am sorry !!!
Colour is important only when DIRECT sun solar radiation, and nothing to do with thermal radiation.
For me personally it is interesting because half of my wings´ down sides are light and
half of them are dark. You can be sure I am a happy man today - right choosing makes
always good for builder - especially aviation safety questions.
Please notice couple of important things:
1) I have dark colour only underside, not sides or upper side (except letters, that´s bad).
2) I do not recommend anybody to paint their Europa uppersides or even sides
anything but white or very light (because of solar radiation). Otherwise be careful.
3) If you like to paint ONLY underside dark, you can do it where ever you live and fly,
even in the equator (please do not fly much uppside down!).
4) where ever you live and keep your plane out, be careful when on the asphalt
because or thermal radiation (nothing to do w plane´s colour, white or black). If a hot
day, move it away to the hangar or at least to the grass surface. That is good
because heat energy makes water in plants to steam and so it is cooler.
5) If you paint it only white, you can forget this topic but please notice point 4!
Painting only white is easier to paint and maintain and also cheeper to paint
and maintain but so boring. If it´s look means nothing, please paint white.
Otherwise you have to think and use your own brains and that is very hard.
Look those Chinese /North Korean girls; all have or used to have
similar green uniform. Sexy?
Karel; this is not only for you but I have done my best to provoke some of you.
Please do not take personally - your golden strips are extremely beautiful
(those professors told me also some facts about high price heat reflecting
dark metallic colours, I am sure your strips are safe and you can fly peace
in your heart, also in a sunny day).
I hardly can wait comments.
Me personally - will not continue this topic any more. I was right as usually
and that is enough for me. What is the most important thing - It is not
necessary to repaint my plane. If I would paint it again, I did like to do same.
Tim: N914XS suffered case 4 - hot asphalt - not a colour relative problem.
Joyce: you wrote "The heat radiating from the ground to the underside of the
plane was enough to soften it, so that heel pressure when we got back in
distorted the skins!
It is worth taking the skin colour and heating possibilities
seriously! Regards, David Joyce G-XSDJ"
Now you can be sure: your Europa´s down side colour had nothing to do with
your problems in Morocco. White colour - same situation. The fact is: you kept
your plane in too hot conditions. Do not fly to hot hell by Europa and if you do so,
keep it in hangar or in good shadow!
Gentlemen, you can be sure I will take my head of from hot ass now.
And continue to fly my Europa with "dark underside colour"!
This colour topic was a good example of "trust only yourself and your senses".
And some individuals out there - who have kindly supported me - just thanks.
Raimo
=====
Raimo M W Toivio
OH-XRT Europa XS Mono #417, The Experimental of The Year (w DARK UNDERSIDE)
OH-CVK C172 Skyhawk, totally restored 2006-2007
OH-BLL Beechcraft C45, w radial engines (grounded)
37500 Lempaala
Finland
tel + 358 3 3753 777
fax + 358 3 3753 100
gsm + 358 40 590 1450
raimo.toivio(at)rwm.fi (raimo.toivio(at)rwm.fi)
www.rwm.fi
[quote] ---
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
|
|
| Back to top |
|
 |
rparigor(at)suffolk.lib.n
Guest
|
| Posted: Fri Aug 03, 2007 8:21 am Post subject: Europa colours /The facts |
|
|
Hello Raimo
Thank you for your posting on "colour & temp".
I think you are missing vital consideration.
What about a surface that reflects a reasonable amount like like cement
runways and parking areas?
I am a hot air balloonist. My last homebuilt is a huge 8 ball, 95,036
cubic feet (majority is black). When there is good solar energy around, I
can take a person in a harness attached to the envelope and fly them solar
powered. It works far better on a white runway compared to black taxiway.
I attribute this to reflection to lower part of balloon in addition to
direct solar.
I expect reflection from a cement surface can heat lower of Europa less
whenm it is white than dark.
The very best conditions I have had for solar flight was on a frozen lake
covered with snow when it was -20F. This is in part to do with thick air,
but amount of heat generated to dark was very impressive. It was dead calm
and an awful lot of cold clothes came off, and packing away was mini
summertime.
If calm wind and strong sun reflecting off snow, it would be well advised
to measure underside of dark composite, I have feeling it could surprise
you.
Ron Parigoris
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
|
|
| Back to top |
|
|
europa flugzeug fabrik
Joined: 13 Feb 2006
Posts: 65
Location: North Coast, USA
|
| Posted: Sat Aug 04, 2007 12:34 pm Post subject: Re: Europa colours /The facts |
|
|
In the interest of adding my amateur science here [  ], I have this digital, infrared temperature reading, gun thingy which is remarkably accurate. Have also an SUV with much sculpting on the body for different sun angles, in med-dark gray-green metallic. The paint reads 10F-degrees below its various black parts on a sunny day. Like today, bright-sun, 78-80F. The highest temp near midday read 135F, for places on the car most perpendicular to the sun, or 55F above ambient. On the side of the vehicle more facing the noon sun, highest temp for a pure vertical surface was 110F, or 30F above ambient. For lowest side surfaces, more angled toward the ground, highest was only 25F above ambient. These side temps (110 or less) will not soften fiberglass, even on an ambient day of 95F, or resulting 125F worst case.
At 2:30PM, a very thin overcast moved over, but still classed as a sunny day, all measured temps dropped significantly, like 20F. So, for a Europa whose lower portion of the fuse is painted in a less brutal color than my SUV, the more perpendicular angle will occur as the sun is nearer the horizon, but through all that similar atmospheric stuff, we know that the sun does not feel as hot. On a clearer day, I shall test again.
As to heat reflection from the ground, when the sun was at a midday angle to best reflect off the concrete (reading 105F), I "shot" the rocker panels. This is metal, painted black on my SUV, underneath the door bottoms, and why in U.S. they're called "rockers," who knows. They are more angled down toward the ground than the door above, but still read about 10F higher than the dark gray above it. I then shot the temp on the bottom side of the rocker, parallel to earth, and it read another 10F higher yet. However, this is 8 inches above ground. This would be a function of distance for sure, and I'll guess it's an inverse-square relationship. This suggests that the monowheel would be more affected than a tri-gear.
Thus, a possible explanation for the damage to the factory demonstrator with the dark blue bottom paint was a combination of monowheel which it was, hot day, black asphalt ramp, and after a flight where we're adding engine room heat to the the affected area. Accordingly, on my tri-gear, I have no problem with painting my Europa's lower 40% in color less brutal than that blue.
Fred F.
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
|
|
| Back to top |
|
|
UVTReith(at)aol.com
Guest
|
| Posted: Mon Aug 06, 2007 4:17 am Post subject: Europa colours /The facts |
|
|
Hallo Raimo, Hallo Europa Family,
first of all congratulations to your baby and your first flights, Reimo.
Once you made a remark during rolling exercise. - " Oh, she is also flying ! "
Have you made a turn around or have you stopped flying?
Somebody told me once:
" When the bird is off the ground during your rolling exercises continue with flying. By sudden reduce of the power, the plane can drop down due to the lost of the prop wash effect."
An answer from some experts will be very welcome, as I will start in two or three weeks time with my roll outs.
But now to the topic of this eMail: Europa Colours / The Fact
Attached is a picture of an Austrian Europa Classic Tri-Gear.
I guess the Monowheel was changed to a tri-Gear recently, as this is kit 173.
The full approval was given in 2000.
As you can see, this bird looks still very nice.
Best Regards,
Bruno Reith / UVT Reith
europa-aircraft-germany
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
| Description: |
|
| Filesize: |
464.29 KB |
| Viewed: |
445 Time(s) |
|
|
|
| Back to top |
|
|
raimo.toivio(at)rwm.fi
Guest
|
| Posted: Fri Aug 10, 2007 8:57 am Post subject: Europa colours /The facts |
|
|
Guten Tag, Bruno
und danke sehr schön!
OE-CMW looks great and I am sure
it is going to do so decades. Of course!
By the way very intelligent painting scheme...
I have no ground loops and still flying.
In fact I had a rare opportunity
to fly together with Sir Rolph Muller, English gentleman.
It was last Monday and he will later
write a report of my OH-XRT´s characteristics.
My intend is to end upp w my test flight sessions during August-September.
I wish you luck with your roll outs.
Do enjoy every moments - they will not come back.
Regards, Raimo
=========
Raimo M W Toivio
OH-XRT Europa XS Mono #417, The Experimental of The Year, about 20 hrs & 100 landings.
OH-CVK C172 Skyhawk, totally restored 2006-2007
OH-BLL Beechcraft C45, w radial engines (grounded)
37500 Lempaala
Finland
tel + 358 3 3753 777
fax + 358 3 3753 100
gsm + 358 40 590 1450
raimo.toivio(at)rwm.fi (raimo.toivio(at)rwm.fi)
www.rwm.fi
[quote] ---
| | - The Matronics Europa-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Europa-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
