This is a House Swift - you can see the pale rump on this clear photo.
Cheers
Mike K Author: ajohn Time: 10/01/2010 09:47
I agree this is a house swift. The underwing looks paler because of the angle of the bird, so that the wing is catching the sunlight Author: wkcheng Time: 10/01/2010 21:33
Thanks both kmike and ajohn for the identification and explanation.
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