Heavily modified Gulfstream II of Missile Defense Agency (MDA) of USA used as a High Altitude Observatory platform .

Gulfstream G-IIB - 125  High Altitude Observatory platform. 

Gulfstream G-IIB - 125  (Regd. N178B) of United States Missile Defence Agency is used as a High Altitude Observatory platform. 

The Gulfstream II aircraft has been modified by installing a large front dorsal fairing, that houses a system of Electro-optical / Infrared Systems (EO/IR) sensors.

The aircraft has a maximum ceiling of 45,000ft, a range of 3,000nm with cruising speed of 460kts. Aircraft is powered by two Rolls Royce Spey engines which have a thrust rating of 11,400lb per engine.

The Missile Defense Agency (MDA)

The Missile Defense Agency (MDA) is the research, development, and acquisition wing of the Department of Defense. MDA employs government civilians, military service personnels, and contractors across the United States of America.

The Missile Defense Agency is dedicated for the development of several ballistic missile defense (BMD) systems, that includes the Midcourse Defense system, Patriot PAC-3 and Aegis BMD .

Recently, the 21.7 years old Gulfstream G-IIB - 125  (Regd. N178B) of United States Missile Defence Agency caught in camera while arriving at RAF Mildenhall (MHZ) from Lajes(TER) .