Sierra Industries has brought its Stallion Citation to the show. The company was awarded its US Federal Aviation Administration supplemental type certificate in August last year and at the end of April it received European approval for the modifications. So far 28 Eagle II and eight Stallion modifications have been performed.

The modification for the Citation 501SPs calls for removal of the original Pratt & Whitney JT15D-1A engines to be replaced with more powerful Williams FJ44-2As rated at 2,300lb (10kN). This allows a direct climb to 43,000ft (13,000m) in 24min.
The modified aircraft will fly an extra 370km (200nm) and at economy cruise consumes 270kg (600lb) of fuel per hour.  It is also quicker, at 385kt (710km/h).

The modification costs $1.53 million, less any refunds from engine core exchanges.

A winglet modification is also in flight testing, but preliminary data has shown an increase in climb rates by 6% and a speed increase of 3-4%.  Sierra expects certification of the winglet in the third quarter of this year and expects it cost $50,000-75,000.
“This is an important milestone for us and EASA approval creates a viable product for the European and Middle Eastern market.  With our ‘right now’ availability we believe our modifications are a very attractive product for our customers across the ocean,” says chief executive Mark Huffstutler.


Source: Flight Daily News