Kolb MKIII Tweaks & Hints

N420P (4 2 Old Poops) is a Kolb MKIII Classic, a joy-to-fly 2 seat light aircraft. Construction began in March 1995, and the aircraft first flew in October of 1996. Other than the shape of the rudder, squared off to cosmetically match the rest of the tail, the aircraft was built to plans, but has since undergone a number of minor modifications to enhance comfort and performance. It is based at an 800' grass strip, and operates very comfortably, solo or dual, from that size runway. The aircraft stalls solo at 27-28, dual at 32-33. (Love those vortex generators!) Normal cruise speed is anywhere between 50 and 75 at 4500-6000 rpm, full throttle level flight is around 85 mph at 6500 rpm. The Rotax 65 hp 582 ( B gearbox, 2.58:1 reduction) with 2-blade 68" Ivoprop uses 4 gph at 60 mph & 5000 rpm, and around 5 gph at 75 mph & 6000 rpm. Empty weight is 525 pounds with a full electrical system, 720 channel radio, transponder, mode C, intercom, and a ballistic parachute, and is day/night VFR legal.

Article & Picture Index

  15 Gallon Fuel Tanks

  Controls & Avionics

Pitot Tubes & Lighter Ailerons

  The Need For Speed...

  Wingtip Navigation Lights

Aileron Hinge

  Fine Tuning the Flaps

  Trim Tabs & Wheel Pants

Landing Lights & Antenna

 Vortex Generators

Gull Wing Doors

Principles of 2-Stroke Jetting, & Reading The Plugs

Firestar II Tweaks and Hints

N582EM is a Firestar II with a Rotax 582 engine. It has been reinforced in the motor mount area to handle the extra torque of the 582, as the original upper fuselage structure was insufficient for the torque of the 582 and could be damaged in turbulence at full throttle. This engine is an excellent choice for the aircraft, as it gives outstanding performance on takoff and climbout, while allowing cruise power settings to be very low. Typically the airplane cruises at 65 mph @ 5000 rpm with commensurate low fuel consumption and inproved engine durability.

 Replacing the Original Sling Seat

 Heavy Ailerons

Vortex Generators 

 Battery & Hot Box mounts

 Door Latch & Rear Enclosure

 Muffler & Exhaust Mods

 Changing Elevator Incidence

 582 Structural Mods


Had some grief a while back from a broken landing gear/axle fitting. Gave us an opportunity to do some mods:

 Landing Gear Update

 Wingtip Mods

 Fuel Tank & Storage Mod


FireFly pictures

The pictures showing the free air engine and the muffler forward over the wing center section were taken in the spring of 2018.

Since that time, the windshield has been changed, the free air engine has been replaced with a fan cooled engine, and the muffler is alongside the engine.

The pitot tube has also been changed.


Instrument panel has airspeed, variometer, EGT/CHT, tach, and an antique altimeter out of an automobile! This was a happy find, because it only weighs 3 ounces. It is easy to adjust and quite accurate.

You can see the windshield locks hanging down on either side of the picture. The windshield is easy to open and close, stays locked securely, and is easy to get your feet inside without hitting it.

The pink thing in front of the rudder pedals is the paperwork. It is signed off as Part 103 legal.



The two red caps are atop the throttle lever, just to the right of it is the brake lever. Just to the right of the seat is the bag for the hand deployed parachute. Seat belts are a 4-point harness.


Windshield in the open position.


Elevator trim.


Disc brakes are cable operated, originally for a bicycle, they work very well.





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