Page 8 - Volume 16 Number 2

seen more enhancements than a Hollywood starlet past her golden years. Hawker Beechcraft (along with Raisbeck, BLR, and others) has had some very talented “plastic surgeons” (engineers) creating King Air improvements over the years. Their ability to perpetually enhance the basic design is impressive and admirable. Therein lies the appeal of a truly timeless “classic.” Like the Hollywood starlet, the King Air design has proven that it can weather time and still keep an audience satisfied and asking for more.
When A Trick Is No Illusion
The latest and greatest of the KA200‘s is the King Air 250, which retains the 200GT’s 850 shp PT6A-52 engines but achieves some serious performance gains above
its brethren. The 250 has a few tricks up its sleeve helping it. These tricks are neither new technology nor new ideas; you’ve encountered them before in other applications, including many other King Air variants, both in new production King Airs or aftermarket STCs. These performance-enhancing additions make up the major ingredients used to “soup up” the 200GT, creating the new 250.
The least-obvious modification is the incorporation of Raisbeck’s Ram Air Recovery (RAR) System, which modifies the PT6A’s inertial separator from a flat-plate shape into a more complex airfoil design, reducing the amount of ram air lost when the inertial separators (a.k.a., ice vanes) are extended, greatly minimizing the drop in power. So, pilots can be more liberal about
separator use because there is little or no performance penalty. This is not only good for performance, but it’s also likely to benefit engine life and operating costs, as pilots will be less reluctant to use the separators and, thus, less likely to ingest ice chunks, ground debris, or other sources of FOD. The RAR system is a win-win situation; its probably a bit more complex and expensive to build and install than the flat- plate design, but the mechanical operation is nearly identical to the older system, so there’s no increased maintenance to speak of.
Visually, the King Air 250’s most obvious modifications are its winglets, which have been around for decades. Hawker Beechcraft has used them on its larger King Air variants for many years, so they’re almost “old hat.” Nonetheless,
6 • TWIN & TURBINE
FEBRUARY 2012