Thursday, August 25, 2011

Adjusted the rudder cables today to get a straighter track on final. The nose wheel was slightly off compared to the rudder and acting as a rudder itself. Need to loosen them a bit or allow them to stretch.

Monday, August 15, 2011

The weather has not been very cooperative for test flying recently. Taking advantage of this down time I opened all the inspection ports and did a full day inspection on the plane.

Additional grease was required and I vacuumed out more chaff that has appeared. More grease was required in the inspection bays around the controls and bearings. Some additional grease was required between the nose strut and the accessory shelf.

In addition I added velcro fasteners to all the seating and installed a document holder.

Sunday, August 07, 2011

I added another 1.6 hours today in the air.

Several tests were done. First was a temperature measurement of the avionics area during taxi, pre-flight and in flight. Next was a test of flap deployment and retraction. finally I measured time-to=climb and have first numbers for Vy.

The ambient temp was 82F during the test flight. During run-up and taxi the area near the Dynon reached upto 95F. Opening the air hatches reduced this closer to 91F. I may need to install a fan tied to the master bus in the area of the Dynon.

Climbing out to 4000 I explored slow flight some more. The force it takes to deploy the flaps above 60MPH is very high. Realistically you need to be lower than 55MPH, or even 50MPH. I found the flap deployment produced a strong nose down attitude, but ample authority was available in the elevators and ailerons.

With the flaps deployed I attempted slow flight at 40MPH. I may attempt slower flight later. An attempt was made to stall the plane with the flaps deployed, but once again the elevator does not have the authority to produce a high enough attitude to stall the plane.

The transponder was re-verified and flight-following was used during most of the test-flight.

Additionally I reversed the bend of the trailing edge to the elevator. Currently the bend is now about neutral. This helped reduce the amount of nose up trim required for cruise flight. I suspect reflexing the flaps slightly will be the final solution to not requiring too much nose up trim in cruise flight.

The rear locking pin on the pilot side works well, although the door is slightly harder to close.

I did several measurements for Vy. The initial winner for a 4000-5000' climb is 45MPH. The time for 45MPH was several seconds faster than 50MPH. I did attempt 40MPH and 35MPH. The nose attitude of 35MPH is amazing. The ground reference plane of the Dynon just goes out of view. The other runs were made at 70, 65, 60 and 55 MPH.

After landing I did find a small drip was coming from a fuel sampler fitting. After cleaning the area with a cloth and examining it, it looks like the drip is coming from the sampler's hole. I checked the tightness of the fitting and it is secure. Furthermore I pulled on the fitting to make sure that it was fully down and not stuck slightly up. I may need to drain the tank and replace the fitting.

The plane now has 5 hours in the air and 4 flights\takeoffs\landings.

According to the indicated fuel levels, 5 gallons were used in the 1.6 hours of flight. Fuel burn was at 3.1 gallons an hour.

Saturday, August 06, 2011

Added another flight today for 1.4 hours. That brings the new grand total to 2.5 hours of in-flight testing.

The area above AWO started getting bumpy beneath the 4000' scattered layer over AWO, so I took the plane out of the pattern. There is a nice stretch of pasture the runs NW from the airport to the shore.

I ended up climbing all the way to 6k indicated and the plane still had plenty of power, refreshing compared to a 150\O-200.

While up there I did several things. First I contacted Whidbey approach and verified they could pick up the transponder. At first they were just picking up the discrete code. It took me a while to realize that the transponder was on, but not on ALT.

While climbing I played with my airspeed to at least partially verify Vy. Without doing a specific, A\B test, it looks like 55MPH indicated is the answer.

I also explored slow flights and attempted power off stalls. I took the plane all the way down to 40MPH and the plane exhibited good control characteristics. Even with low power settings substantial right rudder was required with the nose high attitude.

Power off stalls were approached with caution. In the end the elevator ( as often reported ) does not have enough authority to stall the plane. The altimeter unwinds ( but not too fast ) and you still have authority in the ailerons and rudder.

I also attempted to pull some Gs and perform tight turns. I was able to turn inside my wake, not hitting it until I straightened out to reverse the turn. Forty-five degrees was as far as I was willing to take it. Even then it was hard to pull more than a G or two, the plane is just that maneuverable.

Enough grease and lube has been added that the rudder now straightens itself out gradually. As the nylon block wears in the rudder should loosen even more.

Part of the testing was fuel usage measurements. The plane started with 10 gallons. After 1.4 on the hobbs the final indicated fuel amount was 5.5 gallons. Power was well below cruise for most of the flight, so 3.5\hour for cruise should be reasonable with 11.5deg pitch.

Today's landing was the best yet. I kept more power into the landing than before and made a good effort not to flare until last minute. Keeping the power up and settling on long final with a slightly nose high attitude ( like a seaplane ) really added a lot of stability to the approach. The improved rudder lubrication also showed through.

The 701 really rides thermals and updrafts. The low wing loading combined with short wings also gives the ride a unique feel. You hear some metal rattle a split second before you get tossed up in the sky. Crossing through a disturbance on one side of the plane produces what I can only describe as a "burble"... like crossing a power boat's wake in a canoe.

The next several flights will be taking the turns tighter, hitting VNE and then adding simulated passenger weight.

After the flight I ended up installing a rear locking pin on the pilot side.