e-a,
It would have been Simpang/Sungai Besi, home of the RMAF Museum. As mentioned earlier, it was probably the HU-16 Albatross that you saw.
20091103-IMG_8719 by
Janner88, on Flickr
However, it could also have been one of Maritim Malaysia's CL415s that visits this base occasionally.
IMG_9566 by
Janner88, on Flickr