Any Starfighter experts here?

[The Rat]

Looking at 104s in natural metal finish, and rarely are the wings left bare, they're usually painted, and often white. Any particular reason for that? TIA

[Weaver]

According to this thread, all the USAF ones with white upper wings had grey (FS16473) on the underside of them:

https://www.britmodeller.com/forums/index.php?/topic/234923310-f-104-reference-thread/&

No explanation why though.

[Weaver]

Here's an explanation that's been offered to the same question:

I've been told by a reliable source (actually, a former professional ramp rat) that the large quantities of hot bleed air, used to lower landing speeds, tended to erode the bare aluminum surface of the wings. The gloss white was actually a special hard epoxy finish used to protect the underlaying airframe. BTW, the bottoms were painted the same light gray as the radome. Later painted schemes apparemtly did not require these extreme measures.
Or so I've been told.

Phil

From here: http://cs.finescale.com/fsm/modeling_subjects/f/2/p/23751/233964.aspx

[Weaver]

I'm seeing other proffered reasons in other discussions, but nothing that I'd say sounded authoritative and/or 100% credible:

Nuclear flash protection (on aircraft tasked as interceptors with no nukes of their own, and only on the wings?)

Smooth finish for aerodynamic reasons (sounds credible since it seemed common on the tails and fins of NMF 104s too)

Maintenance reasons: it made hydraulic leaks show up better (why not on other aircraft then?)

Protection because the wing was used as a walkway by pilots in the absence of a ladder (why quick-dirtying white though? You'd think grey or black would be better if that was the reason. Also, why paint the undersides and the tails/fin?)

Reflecting the sun's heat to keep the wings cooler: allegedly there were temperature sensors in the wings that fed info to a throttle-limiting system designed to prevent the airframe getting damaged by aerodynamic heating at very high speeds, and these could give a false reading if solar heat was added to the mix.

[The Rat]

Thanks guys! I got an answer over on Hyperscale about it being to help preserve the laminar flow. Sounds reasonable, with wings that small you need all the lift insurance you can get. 

[Weaver]

Makes sense: with such a small wing area, every small ripple would have a proportionally greater effect than on a larger wing.

[NARSES2]

My first instinct was "protect the laminar flow" as per the Mustang. Glad it was on the ball for once 

[PR19_Kit]

Maybe because it just looked 'cool'? 

If you could look 'cool' back then of course, you may have looked 'hip', or 'groovy' even..... 

[KJ_Lesnick]

Thanks guys! I got an answer over on Hyperscale about it being to help preserve the laminar flow.

I got more about it not eroding the skin...