John,
The Ilya Mouromets was, in fact, designed by Igor Sikorsky.
Sikorsky was born in Kiev and designed aircraft in Russia until he left in 1918. He then ended up in the United States, where he started the
'Sikorsky Aero Engineering Corporation in 1923.
The above was taken from Durkota, 'The
Imperial Russian Air Service' which is an excellent overview of Russian military aviation up to 1918.
It is expensive, but if you are serious I suggest you find a copy.
I do not know if Igor Sikorsky was related to the Polish leader, but interestingly, there is (was?) a well known specialist in Polish history named Norman Davies... might you two be related?
VBR,
MDD