My inside sources told me this top secret information, on a need to know basis only. I was swore to secrecy and granted access to the eye only black
ops documents that say this was adopted from a MIG-21 and stuck on a BIZ JET platfrom to test a new radar upgrade for MiG-21's.
It has been moth balled since AT LEAST 2001
( Actually not top secret - just wanted to add that! )
as One Man Short of Manhood said it's a Mig nose slapped into a busines jet for IAI radar testing, the intake part of the nose probably left there
because it interferes with the radar, either on a positive or negative way, but it has to be there for the testing to be accurate