Black stripes on TWA wings

[Will]

Does anyone know why TWA used to paint a black stripe on the top of their aircrafts' wings? The stripe was typically 6 feet wide, and ran from the front edge to the trailing edge of the flaps, located about 2/5 of the distance from the wing root to the tip. The stripe wouldn't extend onto the leading edge devices, if any.

The only explanation I've heard is that they might be for better visual detection of icing, but that seems a little unlikely, as I'm not sure they can always be visualized from the cockpit. And anyway, ice would form on the leading edge, not on the upper surface.

They are very distinctive, so I wonder if they are for better recognition of TWA aircraft from satellite photos? TWA got hijacked a lot back in the early days of jet travel and maybe they were interested in finding their assets wherever they were, by whatever means available.

Any other ideas?

[Mariano]

Will,

I believe those are for (clear) ice detection, especially before takeoff as, during freezing precipitation, ice would form all over the wing (and other surfaces) when taxiing or while static in line for departure (once anti-icing fluid has ran its course). The black makes the (clear) ice coating stick out a bit better when compared to the rest of the wing.

As holdover time nears its end, a visual inspection is the only way to determine whether it is safe to depart or whether a trip back to the de-icing pad is needed, hence the black stripes.

I think ANA still uses those stripes.

On 77Ws, those are meant to deleniate the outermost tires for use in conjunction with the tail camera for ground maneuvering operations.

Regards,

Mariano