Honeywell flies a Boeing 757 with a difference. The test aircraft is distinguished from an average 757 by a strange outgrowth - a unique extra engine mount. The third engine on the right-hand side of its forward fuselage is used to test the American equipment manufacturer’s various engines.
Honeywell uses this flying laboratory to test in-flight business jet engines under development. The jet has been used for research and development by the US company since 2008, and has completed more than 400 flight tests in some 15 countries.
Its distinct third-engine pylon is original, because when it comes to certifying a new engine, the test engine is usually installed by General Electric or Rolls-Royce in place of one of the series’ reactors, present under the wing. However, Honeywell’s testbed engine has its limits. It can only be used for small reactors weighing a maximum of around 700 kg.
As for the Boeing 757’s aerodynamics, these are slightly modified. But according to Honeywell, it doesn't affect the overall handling characteristics of the 757, which has over 1,700 flying hours under its belt.