C90/E90 - Kilo Alpha 290 Conversion

Kilo Alpha Logo

The Ultimate Turboprop Conversion

For anyone that knows turboprops, imagine having the ULTIMATE combination of Twin Commander/Conquest II performance with the cabin of a King Air! Well National Flight Services has done it! Spectacular performance from the ground to FL300, immediate throttle response, greater fuel efficiency by up to 15%, and less than half the scheduled engine maintenance of competing conversions! It can all be yours with the Kilo Alpha 290 King Air C/E90 Conversion!

Short Field Capabilities of Kilo Alpha 290

Other conversions offer power at altitude, but do not utilize the King Air 90 turboprop for its short field capabilities! With the Kilo Alpha 290 Conversion, you no longer have to worry about being able to leave the short strips you land on! C & E90s with the Kilo Alpha 290 Conversion utilize two 1000shp TPE331-10AV-511KA engines derated to 715shp on takeoff. This allows for spectacular takeoff performance; using as little as half the takeoff distance of King Air 90 with 550shp PT6s! The each flat rated engine gives you 715shp to FL180, so short fields at high elevations are no sweat for the Kilo Alpha King Air!

The Kilo Alpha 290 Conversion utilizes the McCauley BlackMac five-bladed, noise reduction propeller system which not only makes our King Air 90 cabins quieter than most C/E90s, but it also turns a high enough RPM not to bog down your engines in slow operation. When combined with the 1000SHP TPE331-10AV-511KA, our prop-engine combination allow you to climb out at 1000FPM on one engine; that is 526FPM more than the competition!

Kilo Alpha 290

A Great Business Decision

From a maintenance stand point, the Kilo Alpha 290 Conversion makes great business sense! Not only will you get to altitude faster where you burn less fuel, but with the Kilo Alpha 290 Conversion, there is not a scheduled engine maintenance event for 3500 hours! And your TBO is 7000 hours! That is twice the engine life of the competing PT6 conversion and almost four times the life of the Walther Conversion! You may not even see a pricy engine maintenance event for as long as you own your aircraft! And fly as much as you want!

Completion Time

Fortunately though, all good things come to those who wait. The Kilo Alpha 290 Conversion comes with a longer completion time than the competition; being completed in 6 to 9 weeks depending on the lead time. However, the Kilo Alpha 290 Conversion is a COMPLETE AIRCRAFT MODIFICATION including a complete transformation from the firewall forward on both engines. This also includes propellers, gauges, wiring, dual aft body strakes, stainless steel sootless exhaust, and more! Besides, the longer waiting time vastly outweighs the time you'll have to spend in the shop changing out or maintaining your PT6s/Walthers down the road. We can have your aircraft interior refurbished during your down time as well! Avionics updates too!

Engine Cutout

The TPE331 Performance Advantages

For those that are skeptical about Honeywell/Garrett TPE331 power, there are many advantages you get with a TPE331 that you simply sacrifice for the quieter ground operation of a Pratt & Whitney PT6. To start, TPE331s are 15% more efficient than competing PT6s because they are direct-driven engines (with a physical link between the hot section and the prop shaft). PT6s are also installed backwards, with the exhaust exiting the engine just behind the propeller. Through many years of operation, the PT6 has been perfected quite a bit, however the design is still inefficient. With the TPE331, the engine is actually installed right-side-forward eliminating drag and giving you close to 60hp from the exhaust stack.

Other advantages to TPE331s include much better throttle response, less of a power sacrifice with inlet heat, and they are just a quiet as a PT6 in flight.

Despite common belief, TPE331s are not hard to start and are often given a bad reputation. With any turbine engine, it is recommended to have good batteries for quick starts to maintain a healthy hot section. Hot starts are unfortunately a reality with all turbine engines and are just as common with PT6s. For added convenience, the Kilo Alpha Conversion installs both a parallel and series start modes to handle any start situation that may occur; including extremely cold temperature climates.

Kilo Alpha Conversion!

The TPE331 Maintenance Cost Advantages

TPE331s from a maintenance standpoint have longer TBOs and cost as little as 20% less at scheduled engine maintenance events for your first TBO period (from zero time until required engine overhaul hour limitation). During reoccurring TBO intervals, TPE331s can be as much as 45% less expensive to operate than PT6s due to horrific PT6 turbine wheel costs! That amounts to a HUGE SAVINGS for TPE331 operators!

For the conversion that will offer you the best performance for your hard earned dollar, call National Flight Services today to create your ULTIMATE TURBOPROP!


  • Powerful, yet Efficient Honeywell TPE331-10AV-511KA Engines!
  • McCauley BlackMac 5 Bladed Noise Reduction Propellers!
  • National Flight's Sootless Exhaust Modification!
  • Dual Aft Body Strakes!
  • Increased Cruise Speed - Up To 290 Knots True Airspeed!
  • Increased Range - Up To 1,500NM with the C90 - 2000NM with the E90!
  • Increased Climb Rate - 4,000 Feet Per Minute Climb Rate off the Ground!
  • Increased High Altitude Climb - 2,500 Feet Per Minute Climb Rate at 25,000 Feet!

The Kilo Alpha 290 King Air C/E90 Conversion Includes:

The Kilo Alpha 290 King Air�C/E90 Conversion

  • Honeywell TPE331-10AV-511KA Engines
    • Factory New Engines - Factory Warranty
    • 1,000 Thermodynamic SHP – Direct Drive Power
    • 7,000 Hour Time Between Overhaul
    • 3,500 Hour Midlife Inspection
    • FAA Supplemental Type Certificated w/ FAA Approved Maintenance Program

Engine Inlet

  • McCauley BlackMac Five Bladed Noise Reduction Propellers
    • Factory New Prop w/ Factory Warranty
    • Significant Noise Reduction
    • Improved Climb Rate
    • State of the Art Hub & De-ice Technology
    • Appealing New Look

Raisbeck Aft Body Strakes

  • Raisbeck Aft Body Strakes
    • Greater Pilot Control & Handling Qualities
    • Increased Climb & Cruise Performance
    • Improved Aesthetics

Kilo Alpha 290 Soot Reduction Exhaust System

  • Kilo Alpha 290 Soot Reduction Exhaust System
    • Nearly 100% Exhaust Soot Reduction - Fresh Air System

Kilo Alpha 290 Conversion applies to models: C90, C90-1, C90A, C90B, C90GT & E90.

Complete aircraft packages are put together on a per customer basis and with any King Air C90, E90 or complete Kilo Alpha 290 converted aircraft. Please call for more information.