Steven wrote:
That depends on the albedo of the airplane, the angle it presented to the
sun, the brightness of the landing light, and the exact direction it was
facing. It does not sound unreasonable to me, although I wasn't there at
that exact moment.

The landing light may have made the arriving aircraft harder to spot. In
WWII it was found that forward facing lights mounted on ASW aircraft allowed
them to get closer to surfaced submarines before being spotted.

I expect the pilots of those planes knew enough to make their attack
runs with the sun at their back; i.e. a direction where the vision of
the submariners would be impaired.
Lights can be used as camouflage when you have a relatively dark plane
silouetted against a brighter sky. But in this circumstance where the
landing plane is observed from the direction of an almost setting sun
you have the opposite situation; a brightly illuminated plane seen
against an already darkening sky. Adding lights would then only make
the plane more visible.

Similarly the bright white winter coat of an arctic hare is good
camouflage, but the same color on an albino rabbit in a hay field just
makes it stand out as an obvious target.