Why the nose paintedin black?

[MHN_pilot]

Hi!

It might be a silly question but the thingis that I always wondered why in classic jets the radome was painted in black, as it can still be seen in some iberia and alitalia birds for example. Something to do with the radar maybe? just "fashion"?

Thanks!

[sb_sfo]

Supposedly to knock down reflected light. Think NFL players with charcoal under their eyes.

[MHN_pilot]

Ok sb_sfo I'd have never imagined the reason....

Thanks!

[GarageYears]

You folk surprise me sometimes?

Radomes were originally made of fibreglass and covered the wx radar, and most importantly were sensitive to the thickness of the paint application - any greater than 12-15mils would reduce the radar efficiency from 90% down to 50-60% and worse with thicker paint. Part of the problem "back then" was the composition of the paint contained metallic salts and oxides that could impair the signal.

Due to both changes in the composition of the radome (now many are composites) and great improvements in paint technology, it is possible to paint the radome in the same color as the rest of the aircraft. It is still necessary to be careful with paint layer thickness, but the color issue is now largely solved.

When repainting a radome it is still generally necessary to remove the previous paint layers to ensure the signal remains unimpaired.

The comments regarding anti-glare are still correct for some aircraft, but that was perhaps more style than substance.

- GY

[kijangnim]

GarageYears

[deltayankee]

They used to paint the area between radome and flight deck windows black too, presumably this was only for glare attenuation. Look at the AF airbus repainted in classic colours and you'll see this.

[glhcarl]

Radomes (nose?) are interchangable. Example, you can take one off any 737 and put it on any other 737 without modification to the radome or airframe. By painting the radome a single color like black or white you don't have to worry about any logos/paint schemes lining up, from aircraft to aircraft.

[avionic type]

Or the old radome was damaged and the new one won't get painted until the next repaint, happened a lot in my day

[Dairyground]

Radomes (nose?) are interchangable. Example, you can take one off any 737 and put it on any other 737 without modification to the radome or airframe. By painting the radome a single color like black or white you don't have to worry about any logos/paint schemes lining up, from aircraft to aircraft.

Or the old radome was damaged and the new one won't get painted until the next repaint, happened a lot in my day

A bit of thread drift, but it wasn't only radomes. I recall seeing at least one BAC 1-11 with a rudder painted in one BA colour scheme and the rest of the aircraft painted in another. I forget whether the rudder or the rest was the more up to date.

[freespinner]

most radomes are still made of fibreglass combined with a resin-composite construction.But the paints materials have changed over the years.

[aviatordom]

Is this why some BA 757s have a black circle around the nose?

[Bolty McBolt]

As previously stated in this thread early paints contain “metallic salts and oxides” and these paints were used to protect the fibre glass structures from the degrading effects from suns rays UV etc. I was once told the black paint used originally on ray domes is a lacquer.
It allowed the thinnest application of paint to protect the fibre glass composite structure from elements without impeding the radars performance. The paint needed to be black as black was the only pigment that offered a protective solution without compromise of the radar. Later I have seen ray domes painted black in a MIL- spec non magnetic Black polyurethane paint on F111 and C130s perhaps out of tradition ?
My 2 cents

[tom775257]

<<Is this why some BA 757s have a black circle around the nose?>>

I think it might be to differentiate BA aircraft that have MLS capability, but stand to be corrected.