Kitfox IV
Speedster
N4JU
 

 

 

Aircraft Specs & Data

The following Aircraft Data have been composed during many flight tests. The testing has been conducted primarily at about 7000 ft and during the warmer season. The engine together with the Warp Drive has the capability to output a considerable torque but also an impressive short field take off capability. To achieve smooth operation of the engine careful adjustment of the fuel flow has to be made whenever another power setting is selected.
 

Dimensions + Weight


Spatial Dimensions - with the wings spread
Length over all 226 inch       wingspan 388 inch
 

height with tail wheel on the ground at

- vertical stabilizer  70 inch
-  wingtips                74 inch
-  tip of propeller     90 inch
 

height of tail wheel when in horizontal position 32 inch

 

height of top of tail when horizontal

for take off or w&b measurement       100 inch
 


Spatial Dimensions - with the wings folded
Length over all 264 inch      Width 98 inch
height with tail wheel on the ground at vertical stabilizer 70 inch

Wheel base (center tire) 56.5 inch

Weight
Gross weight 1320 lb
Empty weight+ 1 gal unusable fuel   855 lb
Useful load                                               465 lb

Center of Gravity Limitations
"Measured from the vertical plane (in flight attitude) through the leading edge of the wing, pos in direction to the rear."
Most forward limit        10.2 inch
Most Rearward limit    16.0 inch

CG arm for various stations
Passengers 1 + 2 16.3 inch
"Fuel in wing tank, max 2 x 13 gal ( 156 lb)" 16.5 inch
Baggage sack behind pilots 40.5 inch



Performance

Performance at max load
"Stall speed, full flaps, power ON"   36 kts
"Stall speed, full flaps, power OFF" 39 kts
Cruise speed                                  80 - 91 kts
Max speed VNE                                    109 kts
 


"Take off run, with flaps" 225 ft
"Landing roll, with flaps" 250 ft
 


Rate of climb (at sea level) 1200 ft / min
Best rate of climb speed (at sea level)    VY 56 kts
Best angle of climb speed (at sea level) Vx 50 kts
Maneuvering speed                                          88 kts
 

Maximum Altitude was limited by the cooling capacity of the oil cooler during the climb. An altitude of 10'000 ft has been reached several times. Attention has to be given to avoid a high power on stall.

 

 

 

Speed ranges
Flap extended range white   0 - 50 kts
Operating range green      40 - 100 kts
Caution range yellow      100 - 109 kts
Never Exceed red line           109 + kts
Do NOT attempt Full Power Stall >> Will result in violent spin
Use standard spin recovery procedure



Various Data
Fuel capacity Header tank                       1.3 US gal
Fuel capacity of each (two) wing tank 13 US gal
Fuel type Automotive Unleaded
Oil engine        Castrol GTX SAE 20W-50 3 quarts
Oil gear            Castrol HD 30SAE motor oil 650 ccm
Coolant      50 / 50 Water / Glycol (Prestone EX) 6 quarts
Alternator       12 V  50 A
 

 

 

Equipment / Engine Data

Airframe
Kitfox Classic IV serial # C9407-0041
Kit purchased 1994 1994


Engine
NSI Subaru EA81-120-TBI serial # A12242

Propeller Unit
Propeller gear drive NSI A12 / A430 serial # 072 198 005
transmission ratio   1 : 2.23
Cockpit adjustable prop. drive NSI CAP 140 serial # 0214 97 041
 

Adjustment range:  +27  to -27 (beta) degr. at prop tip
Propeller serial # H6616
number of blades 3
length of blades 73 inch

Landing Gear

Main Wheels 2 wheels
Wheel type: Cleveland 40-28
Tire: 6.00-6 1750 lbs min 25 psi

Tail Wheel:   1 wheel
Scott 3200 Tyre 2.80 / 2.50-4 min 20 psi

Gear springs with Bungee Cord

 

Attachment points for floats are provided


Engine Operating Ranges
Idle      1350 - 1400 RPM
Cruse 3200 - 4500 RPM
Take Off (limited for 5 min) MAX 6200 RPM
MAX Continuous 5800 RPM
NEVER EXCEED 6500 RPM

EGT green arch  1325- 1550 F
EGT yellow arch 1550 - 1600 F
EGT red arch       1600 + F

Oil Pressure red arch         0 - 20 psi
Oil Pressure yellow arch 20 - 35 psi
Oil Pressure green arch  35 - 75 psi
With hot engine increase idle to keep Oil Pressure above 20 psi

Engine Oil Temperature green arch  140 - 235 F
Engine Oil Temperature yellow arch 235 - 275 F
Engine Oil Temperature red arch       275 + F

Transmission Oil Temperature green arch    80 - 200 F
Transmission Oil Temperature yellow arch 200 - 230 F
Transmission Oil Temperature red arch       230 + F

Water temperature green arch 150 - 220 F
Water temperature yellow arch 220 - 245 F
Water temperature red arch       245 + F

Fuel Pressure Low         1 - 3.5 psi
Fuel Pressure Normal 3.5 - 5 psi
Fuel Pressure High         5 + psi
The engine can run without the electrical fuel pump, however with reduced power.
 


Typical Engine Operating Settings
 

Taxi Propeller pitch 14 degr.
Taxi Power setting 4800 RPM

Take Off Propeller pitch 18 degr.
Take Off Power setting 4800 RPM

Best Cruise Propeller pitch 24 degr.
Best Cruise Power setting 3800 RPM

Best Economy Propeller pitch 26 degr.
Best Economy Power setting 3400 RPM

Top Speed Propeller pitch 15 degr.
Top Speed Power setting 5800 RPM

Fast Descent Propeller pitch 26 degr.
Fast Descent Power setting 2800 RPM
 

 

For further information select from the directory at the top right

Contact address is   My.Sky2fly@gmail.com

This page was last maintained  2. 9. 2008