The Beechjet 400A/XP is one of the most popular light jet aircraft due to its cabin size, speed and reliability.  The aircraft is operated domestically and internationally in many missions.   The drawback of the 400A/XP, and most of its competitive aircraft, is its range.  The 400A/XP has a range of only 1,333 nm with 4 passengers and IFR reserves.  This is largely due to the inefficiencies of the Pratt and Whitney JT15D-5 engine and certain aerodynamic inefficiencies within the aircraft nacelle design.  The JT15D engine was one of the earliest high bypass turbo fan engines and thus it is heavy, has high fuel consumption and is costly to maintain.

Additionally, the JT15D-5 engine overhaul cost has increased significantly with overhauls now costing as much as $425,000.   The engines are overhauled at 3600 hours and with the average aircraft operating 450 hours per year, the opportune time for the modification is around the 8 year mark. 

Replacing the JT15D-5 engines with Williams FJ44-3AP’s and installing new aerodynamically improved engine nacelles increases the performance of the Beechjet 400A/XP substantially.

Combining this engine modification with an upgraded state of the art cockpit, will make modified Beechjet 400A - Nextant 400NEXT- a true “category killer”.  Outperforming all other light jets at its price point (Cessna CJ1, CJ2, Citation Ultra, Citation Bravo and the Hawker Beechcraft Premier) and a lower operating cost and a purchase price of aircraft with less performance. (Embraer Phenom, Grob SPn, Cessna CJ3, CJ4, Encore and Learjet 40XR).