It's really great to work for an aviation organization...you can tell the guys in the office "I'm test flying, so I'll be in the air first thing in the mornings, and into the office by noon!", and they understand!
It's been just shy of three weeks in the air, and I've put the 20th hour on the plane this morning. I uncowled her for a change to regular oil (break-in complete - ready for detergent oil), and found not a single leak or drip, nothing wearing or vibrating, and all the bits and pieces just where I put them. Oh...one of the blue anodized rings on a firewall eyeball fitting had unscrewed, and was riding down on the throttle cable, but that wouldn't have had any bad consequences...just put it back on and tightened it up!
So far, I have broken in the engine, and done a first run through most of the performance testing - I have a good hack on speeds, climb rates, power settings - all the operational stuff. In addition, I've tried to check out all of the avionics as I have had the chance, and shot a few extra landings at a neighboring wide runway (our runway is closed, and we're flying off a narrow taxiway - not a place I want to be exploring handling qualities!) to get a handle on how she lands.
A few observations...
1) The GRT EFIS coupled to my Garmin 430 has been flawless! I thought for awhile that the glideslope wasn't working, but yesterday and today I slid down an ILS and sure enough, there were the needles. I had just been too high the first time I checked it, and the "needles" were off-scale. Flying with the GRT "Highway in the Sky" function as well as the traditional ILS needles is a real trip - the HiTS display makes it far easier to stay right in the center. Since I wasn't planning on landing, there was no traffic, and I was coming down from an altitude test, I hit the outer marker at about 185 knots and really enjoyed the slide down the glideslope. Very much like flying the Orbiter - only way shallower glideslope, and slower!
2) I solved my heavy left wing in about ten flights of gradual squeezing of the right aileron. I used a hand seemer, and wish that I'd been a little more careful the first time - I got some little dents where the corner of the seemer jaws were. If I had it to do over again, I'd use pieces of wood and a clamp.
3) Van's published numbers are very good. The web site claims 212 mph for the 180 HP, C/S Prop -8, at 8,000', and I have repeatably gotten 186 knots - 214 mph. I climbed up to 17,500' this morning (couldn't go higher without an IFR cleaerance, and can't do that until I'm out of phase 1), and I was still climbing at 500 fpm. Low altitude climb rates are close to 2,000 fpm.
4) Back to the GRT...one of the coolest aspects is the "percent power" computation. After take-off, I reduce RPM to 2500, and then the only thing I use to set power from then on is % power. I haven't really paid any attention to MAP - it is what it is. I never thought such a simple computation would be so useful! And the velocity vector on the PFD display is superb for sticking an altitude for data-taking. It's even superior to flying the altimeter. Put the dot on teh hirizon line, and you are dead level.
5) Ground handling, including landings, has been quite docile - as I had been told to expect. I have stayed way from much crosswind, because of the narrow taxiway/runway, but today the ASOS was callign 8 knots of cross on my return, and that was no problem.
6) I had been worried about how the cockpit temperatures were going to be, having rarely closed the canopy in flight on my Grumman for twenty years. Although I am not flying in the summer, the ventialtion I am getting from the two eyeball vents is quite good, and I expect that while it sure isn't air conditioned, the cockpit will stay pretty comfortable. I used cabin heat for the first time today, and I can say that my right leg got nice and toasty! (I only opened it up a little - I'm sure it will be fine if I need it...)
7) I have noticed some "thrumming" at certain RPM's, and I believe it to be exhaust resonance on the belly. Not worrisome, but a bit tiring. I am still using my non-ANR helmet, and figure that once I go to an ANR headset, that will control it just fine.
I'm about ready to start stability and control stuff, and expand the V-N envelope. That should keep me beusy for the next bunch of hours. I guess I'll go buy some bags of concrete to pile in the back seat for ballast. One of the guys at work wanted me to build a water-ballast system with a tank in each of the baggage compartments, and a pump to varry the CG in flight with a hose in between. Sounds really cool, but I'm not that ambitious! Besides, then I'd have to worry about a pump runaway, water leaks, Failure Mode Effects Analysis, hazard reports on the ballast system...oh, wait a minute, too much like my day job....
Hope this helps encourage all you folks that are close to finishing! I had high expectations for this airplane, and so far, it has surpassed them! (Good thing too...my Grumman sold in a week when I posted it on the Grumman Gang..so I'm back to a single airplane....)
Paul
It's been just shy of three weeks in the air, and I've put the 20th hour on the plane this morning. I uncowled her for a change to regular oil (break-in complete - ready for detergent oil), and found not a single leak or drip, nothing wearing or vibrating, and all the bits and pieces just where I put them. Oh...one of the blue anodized rings on a firewall eyeball fitting had unscrewed, and was riding down on the throttle cable, but that wouldn't have had any bad consequences...just put it back on and tightened it up!
So far, I have broken in the engine, and done a first run through most of the performance testing - I have a good hack on speeds, climb rates, power settings - all the operational stuff. In addition, I've tried to check out all of the avionics as I have had the chance, and shot a few extra landings at a neighboring wide runway (our runway is closed, and we're flying off a narrow taxiway - not a place I want to be exploring handling qualities!) to get a handle on how she lands.
A few observations...
1) The GRT EFIS coupled to my Garmin 430 has been flawless! I thought for awhile that the glideslope wasn't working, but yesterday and today I slid down an ILS and sure enough, there were the needles. I had just been too high the first time I checked it, and the "needles" were off-scale. Flying with the GRT "Highway in the Sky" function as well as the traditional ILS needles is a real trip - the HiTS display makes it far easier to stay right in the center. Since I wasn't planning on landing, there was no traffic, and I was coming down from an altitude test, I hit the outer marker at about 185 knots and really enjoyed the slide down the glideslope. Very much like flying the Orbiter - only way shallower glideslope, and slower!
2) I solved my heavy left wing in about ten flights of gradual squeezing of the right aileron. I used a hand seemer, and wish that I'd been a little more careful the first time - I got some little dents where the corner of the seemer jaws were. If I had it to do over again, I'd use pieces of wood and a clamp.
3) Van's published numbers are very good. The web site claims 212 mph for the 180 HP, C/S Prop -8, at 8,000', and I have repeatably gotten 186 knots - 214 mph. I climbed up to 17,500' this morning (couldn't go higher without an IFR cleaerance, and can't do that until I'm out of phase 1), and I was still climbing at 500 fpm. Low altitude climb rates are close to 2,000 fpm.
4) Back to the GRT...one of the coolest aspects is the "percent power" computation. After take-off, I reduce RPM to 2500, and then the only thing I use to set power from then on is % power. I haven't really paid any attention to MAP - it is what it is. I never thought such a simple computation would be so useful! And the velocity vector on the PFD display is superb for sticking an altitude for data-taking. It's even superior to flying the altimeter. Put the dot on teh hirizon line, and you are dead level.
5) Ground handling, including landings, has been quite docile - as I had been told to expect. I have stayed way from much crosswind, because of the narrow taxiway/runway, but today the ASOS was callign 8 knots of cross on my return, and that was no problem.
6) I had been worried about how the cockpit temperatures were going to be, having rarely closed the canopy in flight on my Grumman for twenty years. Although I am not flying in the summer, the ventialtion I am getting from the two eyeball vents is quite good, and I expect that while it sure isn't air conditioned, the cockpit will stay pretty comfortable. I used cabin heat for the first time today, and I can say that my right leg got nice and toasty! (I only opened it up a little - I'm sure it will be fine if I need it...)
7) I have noticed some "thrumming" at certain RPM's, and I believe it to be exhaust resonance on the belly. Not worrisome, but a bit tiring. I am still using my non-ANR helmet, and figure that once I go to an ANR headset, that will control it just fine.
I'm about ready to start stability and control stuff, and expand the V-N envelope. That should keep me beusy for the next bunch of hours. I guess I'll go buy some bags of concrete to pile in the back seat for ballast. One of the guys at work wanted me to build a water-ballast system with a tank in each of the baggage compartments, and a pump to varry the CG in flight with a hose in between. Sounds really cool, but I'm not that ambitious! Besides, then I'd have to worry about a pump runaway, water leaks, Failure Mode Effects Analysis, hazard reports on the ballast system...oh, wait a minute, too much like my day job....
Hope this helps encourage all you folks that are close to finishing! I had high expectations for this airplane, and so far, it has surpassed them! (Good thing too...my Grumman sold in a week when I posted it on the Grumman Gang..so I'm back to a single airplane....)
Paul
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...fortunately, Sandy at GRT already has numbers for some of the popular engines, and sent me the values for mine.)
