CHAPTER 23 FLIGHT TESTING
On October 6, 2012, I made the first flight in ERacer N382RB. I stayed near the field and climbed to 3000ft with the gear remaining down. After evaluating the flight controls, engine cooling and performance, as well and landing speed controllability, I returned to the runway for an uneventful landing....What an awesome feeling!!!
Below are my Taxi and the first 4 Flight test notes:
Taxi test 1 : Slow taxi with 90 and 180 degree turns. Engine run until CHT=350
Result : Aircraft pulls right and need heavy brakes to turn left and to
stop. Will check brake system.
Taxi test 2 : Slow taxi with 90 and 180 degree turns. Engine run until CHT=350
Result : As above, confirms original findings, left brake failure.
Installed spacers on axles and got vented cap for left brake.
Taxi test 3 : Break-in the pads taxi faster
Result: Speed 25kts and good braking. still pulling right
Checked alignment and found large toe-out on left wheel. Shimmed to paralell
Taxi test 4 : Increase speed and observe handling
Result: Speed 40kts and better handling...no airspeed readout on gauge, only GPS
Ac still turns right easy and left with difficulty
Taxi test 5 : Increase speed on Runway
Result: Speed 55kts, good handling at higher speeds and readout on gauge was 25???
Taxi test 6 : Increase speed on Runway
Result: Speed 75kts, good handling and gauge readout was 50???
Replaced airspeed indicater
Installed new main tires (originals were over 15 years old)
Taxi Test 7 : Increase speed to take-off
Result: Airspeed checks maybe a few higher than GPS and aircraft handled up to 80 kts.
At slow airspeeds, the AC still likes to pull right and turns easy to the right.
Takeoff test 1: Liftoff
Result: Could not get nose to come off with full back elevator, Did 2 runs to confirm.
Changed incidence on canard to specs +3 degrees, I was 2 degrees low.
will re-weigh for takeoff CG again. Brakes did not overheat after 2 taxi runs
but AC still pulls right at slow speeds ..max CHT=360
Taxi Test 8 : Check if nose will lift off at 75, check distance down runway at 75,
Check A/S idicator with GPS, Video Run
Result: Only ran to 60kts for engine test. A/S indicator 5 knots off from GPS.
Taxi test 9 : Go to 90 kts and check elevator nose lift and distance
Result: Nose wheel lifted at about 75kts....excellent
However, left braking for alliglnment has affected takeoffroll distance during
the first 30 kts so I will replace the entire nose fork assembly and pivot to
correct the flawed one that is on the AC.
MAX CHT= 360. #4 hottest. This is as high as CHTs have gone during all test.
Taxi test 10 : Test new nose wheel strut and fork, turns 90 and 180, slow/high speed.
Result: AC tracked straight, turned in both directions easily and overall handled great!
I did a high speed taxi run to 75kts. Nose came off at 72 on GPS. A/S
indicator seems to indicate a little high. I will use the GPS primary and
cross check with indicator. AC ready for first flight.
6 October, 2012
Flight Test 1: Initial flight evaluation .5 hrs
Result: AC rotated nicely...stable takeoff climbed at 100-110
crosswind 130 CHT went to 360 max. Oil temps went to 230..could be better
seemed to stabilize around 220....Aircraft requires a lot of back pressure,
seems nose heavy, need stronger trim.
.5 hours handling good no problems on landing
24lb ballast and book kit cg= 100.2
Flight TEST 2: Same profile: .5 hrs Changes: added voetex generators in front of oil scoop=
RESULT: no improvemnet on oil temps. CHT up to 360, Oil temp up to 235, stabil 220-230.
kind of bumpy today, OAT 75. AS induicator matches GPS most of the time.
AC is still nose heavy, added stronger spring which helped but still seems nose heavy.
14lbs ballast and book kit CG 101.6
Flight Test 3: Same Profile: .5hrs Changes: new oil temp gauge, larger oil cooler scoop,
new baffles additions to #4 cylinder.
More tension on trim lines to hold springs. 10lbs ballast and book kit. CG=102.3
RESULT: Oil temp gauge needs sender so old one was used. OIL temps 190-220...very good, dropped
about 20 degrees, CHTs were the same and maybe a bit higher 340-375 trim was much better
and held most of the pressure. AC flew nice and landing was better...great flight
Flight Test 4: Area profile: 1.3 hours Put the gear up/down test and fly longer (150TAS record data)
RESULT: Gear retract at 110- kts. no problem...speed increase to 120 Gear cycled up and down
and it worked great. Did have a small leak around resevior. Temps were stable at 190.
and CHT 320-340 with gear up and power at 21-2300. Speed stablizes at about 145kts with slight down
deflection in canard. Got speed up to 160kts...no flutter noted.cimbed to 5500ft. In
climb temps went to 360 CHT and 210 oil. 325 CHT and 180 oil temp in cruise.
Above and Below: Test Flight photos
Above left: Me enjoying some of the 40 hour test phase.
Above right: This is a picture taken through one of my strake windows that I decided to add during the construction phase. This gives a nice look-down as well as storage and arm room in the cockpit.
Above: Taxing out for another test flight
Above left: During the 10 hour oil change, I installed an oil heater to preheat the oil on the cold winter days.
As I go into November with 11 test flights complete and 12.2 hours on the aircraft, I will further test the clean and configured stall speeds, the best rate and angle of climb speeds as well as the max speed of this ERacer.
After all test flights, below is the speed and stall info from my ERacer.
Altitude RPM IAS TAS MPH
8000 2200 132 153 175
8000 2300 141 163 187
8000 2400 151 175 201
8000 2500 160 185 212
8000 2600 163 189 217
8000 2700 166 193 221
Lycoming IO-360 with a 66 x 78 propeller
- Canard stall is at about 65 kts in an accelerated as well as a power off stall : clean as well as in a fully configured condition for landing.
-- Power off stalls tend to be more of a gentle drop of the nose.
-- Accelerated stalls tend to result in a bigger nose drop that feels more like a conventional aircraft main wing stall even though it is a canard stall.
Above: A couple pics from test flight # 15. All the work in building is worth it!!!
I have now completed 16 flights and just about 20 hours out of the 40 required in the test phase. At this point, I need to correct a few things:
- Left fuel probe failed so I am replacing it.
- Larger springs on the rudder cables to ensure full rudder deflection at high speeds
- Replace a portion of the hydraulic line that seems to keep leaking
- Build and install two removable cup holders on the passenger side
- I also found a tiny oil leak around my oil temp probe port which needs to be fixed
- Go over entire aircraft and check for loose screws and bolts
I have now completed 20 flights and have logged 25.5 hours.
Rudders works great now at all speeds, the new fuel probe is installed, the Hydraulic line that was leaking has been replaced, the fitting that was leaking oil has been tightened, and I have built a double-cup removable cup holder.
After my last flight, I found that I had a small fuel leak during the flight which was a result of some poor plumbing and engine vibration. One of my fuel lines was putting torque on the "T" fitting coming off the fuel pump. I have ordered a longer line with a 45 angle on one end to fix the problem and I have moved the inline fuel filter that was also causing part of the problem. I will show a before and after pic when I complete the repair.
After getting a couple test flights in and getting the tanks empty, I decided to change out the left fuel probe that was having issues. Now I have 2 fully fuctioning fuel guages, I will still continue to "stick" the tanks before and after each flight.
-- The aircraft holds 18 gallons in each main and almost 2 gallons in the sump for a total of 38 gallons. (I lost a couple gallons of space in each main tank becuase I chose to add the strake storage and window on each side of the aircraft)
-- At 2200-2300 RPM I burn 7.0 - 8.0 gall/hr.
I flew the last 2 flights with the new unfinished hatch. I think its going to work much better.
the last 3 flights have been my right seat test flights.
-- Flight # 23 50lbs in the passenger seat cg-101
-- Flight # 24 100lbs in the passenger seat cg-100
-- Flight # 25 150lbs in the passenger seat cg- 99
-- Flight # 26 200lbs in the passenger seat cg- 98
I find that the aircraft requires more nose up trim as the CG moves forward. However, I can trim off the forces and the aircraft handles the same in all configurations and phases of flight. A tribute to the design.
I prefer flying the aircraft at 103 when solo.
2 Feb, 2013
The 40 hour test flight phase is complete and the aircraft is now signed off, fully operational, and ready to take passengers. Thus completes the Flight test Chapter.
Please reference the "Current Flying" tab for my status and the "Upgrades" tab for any future modifications that I WILL make.....Thanks