The FlightAware staff person I spoke to suggested this question had already been answered in the Forums, but I did not find an answer, so I am asking.
Is there any source of information about arrivals at Heathrow, the same way I can get information from FlightAware about arrivals at any US airport?
I am trying to determine if a specific British Airways flight, BA873, arrived at Heathrow on August 28, 2008, and, if it did arrive normally, what time did it arrive?
The best source is to call the airline. The UK flight data from ASDI cannot be redistributed to the public.
There are many sources for current information outside of flightaware.
The BAA website, flytecomm.com (EGLL), CEEFAX etc., but none of those will have historical data back to August. I doubt even the airline would have immediate access to that either.
However 
, from a plane-spotters’ log site I can tell you**
BA0873 From Moscow, USSR G-BNWB 763 28/08/2008 17:40**
Thank you, Pat206! This was exactly what I needed!
What’s with all the interest in this flight by two “different” posters 
in two different threads for two different arrivals it would seem
discussions.flightaware.com/view … highlight=
Hmmmmm, Ok, back to bed, forgot it was Saturday.
I’m wondering if argus08 and cworster are the same person.
I sent argus a PM that hasn’t been replied to.