Vashon Municipal Airport

Certainly one of the cuter airports I have been to, and never would go with a 150.

Flew off the remaining 1.9 hours of Phase 1 testing on Saturday, staying close to AWO due to weather. Performed and oil change with a new filter and did an engine inspection. Found that the radiator was rubbing the cowling a bit, so I installed some corking. Removed the NACA vent to the oil cooler and aluminum taped off the cooler to help with low oil temps. Also taped off part of the radiator to help with low CHTs.

Tried out the new "16" grass runway. Winds were 120@8kts to 120@10kts. Also finally tried the plane in the rain. All performed as expected.

PIREP: Grass

I finally took the 701 on the grass on Saturday and Sunday. The WX cooperated by providing mostly dry grass and limp windsocks over the weekend. The 701 of course is designed for these sorts of operations with large turf tires, direct linkage steering on the nose, a large rudder and a very centered CG.

After much discussion I decided not to use a full stick back technique for takeoff, nor pulling the stick full after after landing due to possibility of over rotation. Flaps were not used as they cause a “heavy” elevator, greatly increase sink rate and increase the pressure on the nose wheel.

I started with about 10 takeoffs and landings on the pavement to warm up and practice softfield technique. Then I transitioned to about a half dozen takeoffs on the grass with landings on the pavement, then finally approached the grass.

The first several landings were T&Gs so I could get a feel for the surface without committing the full weight of the aircraft to the strip. It also gave me a good initial idea of how much strip I would require. The current grass strip at AWO is 1500 feet. After 4 T&Gs I brought the plane to a full stop and taxied back by the pavement, then progressed to stop & gos. Overall I did 30 landings on Saturday

I found that with no wind on slightly wet grass I currently need about 500 feet from touchdown to get to a full stop solo. Takeoff run from a stop appears to be about 300 feet. Overall I prefer pavement takeoffs due to the 50% less space required. They are faster and just more fun.

After almost 40 hours in my 701 I think landing it on the grass is preferable despite the increased roll distance. The impact is softer and the slipperiness of the surface makes it feel more forgiving. The nose bounces a bit due to the bungee cord without a shock\dampener, but prop clearance did not look to be an issue and you do not feel it in the cockpit, although the video makes it look like I was tossed around.

After a few hours of landings at AWO I ventured south, when down the valley then across Bellevue to BFI for some pattern work. Like with the 150 I requested early bases and added early cross winds. By altitude the crosswinds were not early, but given where I was I still made sure they were OK. Once again the BFI guys are the friendliest ATCs around and even recognized my voice and commented on the plane’s performance.

In addition I tried a David Clark ENC headset. What a world of difference. This is the first active headset I have tried that does not produce an uncomfortable pressure on my ears. It also does not produce an irritating humming sound when on. The active “reduction” is very noticeable and allows me to hear myself without turning on the intercom while on takeoff.

Combined on Saturday I got 4.1 hours in.

The current grass runway at KAWO is on the West side of the hold short line, just north of the skirt and south of the A2 taxiway. There is a new grass runway that will be officially opened soon.

Saturday’s Video:

Sunday I played on the grass more and then ventured out. I ended up at JeffCo to have lunch where I just missed another 701 builder. Then it was out towards Sequim until clouds stopped me, up over Whidbey with a transition, then over Cypress to Bellingham, to Skagit and finally back to AWO.

The video does not really show it well, but saplings really do cover the old Cypress strip. The catch them on film them I would have to get much closer than I was.

Sunday was 3.4 hours in the air. That leaves 1.9 hours left of the 40 hour test period.

Sunday's Video:

Sunday Cypress Island Fly Over:

Hopping around the San Juans again in late October:

With clean fuel filters, I started to test again. Everything is running great, except the plane seems harder to get really slow on approach. This may be a combination of the slightly reflexed flaps and the VGs. Sometime soon I will attempt to move the VGs aft. The weather was lucky enough to provide a nice 8kt cross wind

On Sunday I was going to fly over to Bremerton from AWO, but I ended up getting some more important obligations the meant I would have to be back in Seattle around 1-2pm. After flying for 1.5 in the morning I found out that those plans had been canceled, so I installed some VGs that I had been wanting to test on the elevator, fueled up ( and yes, I tested the fuel at all three sumps ) and went back to flying.

My normal routine for testing out a change like this is to follow the valley and fields Northwest from AWO towards Stanwood and then try turns, stalls, ect at high altitude then return back to AWO to try landings and then more landings to make sure I like the change.

After about 54 minutes of trying out the VGs I hit a problem.

Halfway through a downwind leg at cruise power\attitude I hit an unexpected loss of power.

The engine became rough and power dropped down to an almost stopped state, then came back up gradually, went back down gradually a few seconds later, came back up gradually a few seconds later, went back down, came back up. The loss of power lasted about 45 seconds to a minute. Carb ice crossed my mind while doing the landing. It was similar to the symptoms of carb ice in an O-200, but my installation has constant carb-heat.

At the first sign of the drop I had already started pitching for glide and called out the mayday. There were two planes on final and one on base. The two on final went around, but the pilot in the tow-plane still turned final and did not abort, turn or otherwise react. Several other people on the radio chimed in in an effort to get him to react.

With the 701 I fly my downwind and base no more than ¼ mile out. I turned base just a little North of the numbers and landed the numbers with better than idle power.

Sadly the on board camera had run out of battery and 1) did not catch the engine event 2) did not catch the emergency landing with a HAPL approach that I hope would have made my flight adviser proud.

Up to that point I had put on 2.5 hours alone that day. There was plenty of fuel and I was hallway finished with my downwind at cruise power, so even a failed fuel pump should have not caused this.

After landing I did do a full run up, and everything was fine. It made full power, mags grounded, ect.

The loss-of-power event was caused by a clog that collected in the fuel filter. My morning preflight showed no issues at the gascolator or in the fuel filter. My theory is that debris that had not been swished out of the tanks, along with debris introduced by auto-fuel and some small amounts of sealant collected in the gascolator on the forward edge. Earlier in the morning I performed a test were I wanted to see how far I could taxi with the fuel valve shutoff ( this was due to several accidents this year were some Cessnas had enough fuel to start takeoff with the valve shutoff ). The intentional fuel starvation most likely caused suction in the fuel lines causing the clog to dislodge and move up the fuel line to the filter.

As a result I will be cleaning the filter and gascolator every 20 hours or so.



Video of a short landing:





Video of flap testing\very consistent landings:

Worked on improving the nose gear. First a a piece of phenolic material was installed underneath the nose strut stop. This reduced the friction of the nose strut while in flight. Next the v-notched channels were ground down and polished. The nose strut no longer touches the extrusion in normal flight, but rides when the rudder is at extreme positions.

The friction in the rudder pedal bearings was also reduced by changing the bolt tension down a bit to 25lbs from 30lbs.

In flight the rudder slowly returns to position, but is still not as loose as I would like due to the nature of the nose bearing surfaces.

A new lower nylon bearing had been fabricated and installed last week. The old bearing had shown some signs of wear and had a 2-3mm gap in it. This new bearing was intended to reduce the amount of forward and back shake on landing. Overall the change was successful. The shake is still visible, but it is no longer detectable in the pedals. This may be the nose strut flexing.

I ended up making a side-by-side comparision video of my 701 & 150 taking off and landing. The takeoffs are on the same runway and almost identical conditions. The winds, pilot, amount of fuel, ect were almost the same. What was not the same was how I flew the 701. This was a normal takeoff, not a short field takeoff. For the 150 I did a short takeoff.

The landings were similar in wind. Obviously the runways were different. The 150 land land short. Just drop 40 degrees of flaps and use power to keep from falling out of the sky.

The weather was bad on Saturday and I took it as a chance to try to reduce the friction in the rudder system and reduce nose gear shake on landing.

For the shake I fabricated a new lower nylon bearing. This one has a tighter fit than the original, so the forward\back motion is limited.

To install it the old lower bushing had to be removed. This was an incredible pain. Reaching the bolts is complicated by the nose strut and the muffler. While the nose bearing was out I removed the v-notch channels and machined them down to create a smoother ride. the new shape is a semi-circle instead of t notch.

I also experimented with the strut cap. New pieces were fabricated out of nylon and phenolic to attempt to reduce the nose gear friction. Once all the pieces were re-installed some reduction of friction was made, but not much. In addition new friction was added by the new lower bearing. The lower nose gear needs to be removed again as I found the new machining of the notches allows for full left rudder deflection, but not full right deflection.

There is still too much friction in the rudder system. After much experimentation I can say the friction is mostly from the nose strut. The rudder by itself is free of perceivable friction. Some friction is being added by the rudder pedal assembly bearings. Grease, teflon, lithium, ect does not seem to reduce the pedal friction.

With the nose gear push rods removed, it obvious that the nose gear is the cause of my troubles. By placing washers under the nose strut cap, I tried lowering the nose strut to allow the cross tube to rub the newly machines angle. This was more friction than the strut cap, despite having less contact surface. The addition of a nylon or phenolic piece under the strut cap adds some reduction in friction, but not as much as expected. One idea I have is to place a matching nylon piece on the firewall shelf so the bearing is nylon to nylon. This would require removing\accessing the bolts holding the upper nylon bearing and may be impossible with the nose strut in place.

The final attempt will be to perform the roller bearing mod. Adding the bearings will require removal of the nose strut or the exhaust system. It will also require some way of adding additional material on top of the lower nylon bearing to allow for full deflections.

The roller bearing mod was originally found here: http://www.utdallas.edu/~klaus/Airplane/nose_gear_thrust_bearing.html

The proper bolt length appears to be AN3-37 and the bearings are "DPP4-FS464" from ACS.

Tested gross weight and aft most CG limits. To test the aft limit I flew off the fuel to only 6 gallons and then loaded the baggage compartment with 40lbs shoved to the far back. This is as close to the aft limit as I could get given the baggage hold limits.

Handling at rear CG was slightly lighter. Power-off and powered stall attempts, takeoffs and landings were about the same as solo/no gear.

Next I added 200lbs of sand bags and fueled up to 16 gallons. Starting DA was 2000'. This was also the most forward CG I could obtain according to the numbers.

Takeoff roll was about 300' and climb out was ~700~750FPM. Power-off stall attempts resulted in a lower nose attitude when the elevator lost authority. Poweron stall attempts also resulted in a lower nose attitude.

Landings were very different. The added mass gave the plane much more momentum and was harder to slow. With my standard final approach speed of 60 MPH, the sink rate was higher and the plane felt "faster".

On Sunday I found an issue with the control system. The baggage area was loaded, but in a slightly different way. This caused the piece of nylon I installed underneath the baggage area to shift. The end result was a snag that I felt in the controls check. It took about 30 minutes to locate it and then a few more minutes to fix it.

Lots of flying over the Labor Day weekend. The big item was getting N701GV up to 17990 and running out of VFR airspace. The climb took 38 minutes and 100+ FPM of climb was still left at 50MPH indicated.

Parts were ordered for the roller-bearing mod on the nose gear. This should improve the feel of the rudders in the air. I will also adjust the lower strut bearing to see if it can be tightened and remove the V-notches the nose strut sits on.

Reached 10 hours in the air. Changed the oil and did another under the cowl inspection.

All indications from the magnet filter and oil look good, break in is going well.

Found some evidence of an oil cooler fitter rubbing against the engine mount. This was more flex than expected. The filter was moved and secured down additionally to stop this.

After adjusting the turnbuckles more, it appears that 18lbs tension is the magic number. The slight left turning bias on the ground was traced back to a trailing \ not yet broken in brake pad.

There is still more friction that I would like in the rudder system, so I will install the rolling bearing mod on the nose strut.

The airframe now has about eleven hours in the air.

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.

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.

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.

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.

Here is the POH I created for N701GV. Please copy this and use it for your own purposes.
This POH was heavily inspired by many others including my C150's, The Czech Aircraft Works, Keith Ashcraft and George Race's.

Second flight was on Sunday the 24th. This flight lasted for about 45 minutes, bringing the total time in air to one hour. Thirty-nine left.

The good news is that the door pin on the passenger side worked. I noticed some puckering on the pilot side today, so I will repeat the mod on the other side.

The efforts to reduce the rudder stiffness worked.

Today was a hot day which mad me think about cooling: specifically of the Dynon. The Dynon does not have any fans. After the flight it was hot near the Dynon. I am thinking a NACA style duct may be a good idea to promote cooling of the electronics.

The flight was a basic repeat of the first flight, with the exception of attempting slower flight. I took the plane down to ~50MPH and experienced the same shudder\bobble that I felt in the plane I transition trained in.

When I took off, winds were calm and mostly down the runway. When I landed I had a good cross wind.

During the landing the plane certainly seems to want to shuttle cock into the wind. That or there is a left yaw tendency. I checked the rudder alignment and it appears fine. If the third flight exhibits the same behavior then I will adjust the dorsal fin.

This landing was another firm landing due to flaring too high. I have also noticed that adding power to attempt to slow the settling will result in a ballooning. Adding power just makes the plane climb.

Frabricated a securing mechanism for the passenger side door.

The fix is basically a thick piece of angle riveted to the top side of the factory supplied handle. I then drilled a hole in the free side of the handle and bolted a rod-end there.

The rod end was connected to all thread. I then riveted a piece of tubing onto the door for the all-thread to be retained by. Finally I drilled a hole large enough for the all-thread into the fuselage.

I also spent a large amount of time chasing down friction in the rudder system. The biggest offender was a huge spot I had not greased - the nose strut stop plate! I ended up just giving everything more doses of grease, even the nylon fairings. With the tail tied down I was able to reduce the friction by an order of magnitude.

By the time I was finished with all the other work today the winds had picked up past my threshold. I did a taxi test and a run-up. The door held without any pucker on the ground where it had previously puckered some during run-up.

Taxi tests with the newly loosened steering system were highly encouraging. Friction for ground handling has been reduced to at least a quarter compared to the first flight.