Performance Figures

These are my numbers as of 3/25/2000.

Aircraft:

Zenith Aircraft CH601HD, Taildragger, with Stratus EA-81 Engine.
Plane was built per plans (from a kit).  Zenith's firewall forward kit was used, and the engine was installed per Zenith's and Stratus' instructions.
Plane is currently unpainted.  There is light fabric installed on the cockpit floor, walls, and first 12" of baggage compartment.
Wheel pants (Zenith's, unmodified) are installed on the main wheels.
Plane has a fully equiped instrument panel, including a 7 lb radio and gyros.
Zenith's strobe-only lights are installed.
This plane has only Zenith's 16 gallon fuselage header tank installed.
One 12 lb 18AH battery is installed at the rear of the baggage area, as is one 3 lb 3AH battery.
Propellor is the 70", 3-blade nickel leading-edge composite Warp Drive blade supplied by Zenith in the firewall forward package.  It is pitched at 12.5deg.
The spinner is UHS 10" fiberglass.
Stratus Subaru engine has the standard 2.2:1 reduction unit installed.

The aircraft pitot-static system has been leak checked.  Indicated airspeed at 1000MSL appears to agree with GPS ground speed on no-wind days.

Weight/Center of Gravity:

Empty weight of the aircraft is 654lbs (does NOT include wheel pants.  Does include full oil and water).
The most forward center of gravity is 10.5" (the limit) with full fuel and a 145lb pilot.
The most rearward center of gravity is 17.5" (the limit) and occurs with no fuel, 465 lbs of pilot & passenger, and 49 lbs of baggage.   See wb.xls.

Climb Data

Data was taken with an air temp of 61F, starting around 1000MSL.  Only me (155lbs) on board.

Airspeed

Climb rate

45 KIAS 1200fpm
50 KIAS 1300fpm
55 KIAS 1100fpm

Descents (Glide Slope)

Data was taken with an air temp of 61F, starting at 5000MSL.  Data is with engine at idle (about 910rpm at these airspeeds).  Glide slope data is based off GPS altitude calculation, and as such is not terribly accurate.  Only me (155lbs) on board.

Airspeed Descent Rate Glide Slope
45 KIAS 400fpm 8.0:1
50 KIAS 450fpm 9.5:1
55 KIAS 700fpm 7.3:1
60 KIAS 650fpm 7.2:1

Speed Runs

Data was taken with an air temp of 61F. Only me (155lbs) on board.  Propeller pitch is slowly becoming optimal as the engine wears in and produces more power (at first I could only get 5050rpm out of the engine in level flight - now I'm up to 5350rpm.   5400rpm is red line and max power for the engine).

Altitude Engine Speed Indicated Airspeed Ground Speed
7000MSL 4800rpm 87 KIAS 97 KTS
(112 MPH)
7000MSL 5150rpm
( full throttle=75% pwr)
95 KIAS 104 KTS
(120 MPH)
1000MSL 5350rpm 115 KIAS 107 KTS
(123 MPH)

Service Ceiling Data

I haven't actually got to the service ceiling yet, but here is some high altitude climb data.  Only me (155lbs) on board.

Altitude ROC Full Throttle RPM
10000MSL 600fpm 4800
12000MSL 500fpm 4700
14000MSL 450fpm 4650

Update 10/16/2005:

I had access to a portable oxygen system today so I decided to see how high the plane can go.  Answer is: I still don't know & won't unless I get an instrument rating to enter class A airspace!

Conditions: Pressure 30.145 in Hg.  9 gallons fuel and 165lb pilot onboard.  22% RH.
Altitude:
17,500 MSL.  Air temp was 19F.  This calculates to a Density Altitude of 18,697ft.
Climb rate was still around 100fpm.  Level cruise IAS was 56kts.  Full-throttle RPM was 4200rpm.
It took 36 minutes to climb from takeoff at Meadow Lake Airport (00V), 6840 MSL to 17500 MSL.

 

Takeoff and Landing Distances

As always, I'm sure landing performance could be improved with better pilot technique!
All tests performed at sea level.

Operation Distance
Takeoff, 155lb pilot and 8 gal fuel 350 ft (off ground)
  800 ft (clear 100' AGL)
Landing, 155lb pilot and 8 gal fuel 950 ft, moderate braking

Minimum Controllable Airspeed and Power

Data taken at 1000MSL with only me (155lbs) on board.

Parameter Value
Minimum Easily Controllable Airspeed 40 KIAS
Engine RPM to maintain level flight 3200rpm
Engine RPM required for a Comfortable Takeoff
(used less than 2000' of runway)
4400rpm

Stratus says that without knowing manifold pressure they can only guess at what horsepower the engine might be producing, but their 'wild guess' was 3200rpm=15-20hp,   4400rpm=60hp.

Engine-off Operations

Data taken starting at 5500MSL, OAT of 59F, and only me (155lbs) on board.  Glide slope data is based off GPS altitude calculation, and as such is not terribly accurate.

Parameter Value
Best Glide Speed 45 KIAS
Descent rate at Best Glide Speed 500fpm
Glide Slope 6:1
Stall Speed with engine off 36 KIAS
Speed at which an Air Start can be performed Something over Vne

Stall Speed Data

Data taken at 1000MSL and OAT of 84F. Note that there is evidence of detached airflow (oil-canning) before the actual stall. Solo weight is me (155lbs) and approx 8 gallons of auto gasoline.

Parameter Value
Stall at Solo Weight and 1/2 fuel 30 KIAS
Stall at Gross Weight (1200lbs) 34 KIAS

Miscellaneous Stuff

Parameter Value
Altitude loss for a 180 degree turn during simulated engine failure on takeoff 300 FT

 

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