As previously mentioned, getting the FAA approval to fly your experimental aircraft is only the first step in gaining the full utility of your new airplane. Before the aircraft can enjoy all of the privileges that other certified aircraft do, it must first be tested for either 25 or 40 hours. The duration of my phase 1 test program is 40 hours because my engine and propeller combination is not certified. That is to say, there are no examples of this exact combination on an already certified aircraft.
While in the initial test phase, one is not permitted to carry passengers. There is an exception to this rule involving a passenger who is also a pilot rated in the aircraft, but I did not avail myself of that option.
Forty hours is a long time for sure, but forty hours of flying is still a pretty good time. My phase one area covered a good sized chunk of the Northern Sacramento valley between Lincoln and Corning. There are quite a few small airports dotting the valley and I think I managed to land at each one at least once during my test flying.
The phase one tests are designed to measure the flight envelope of the aircraft. This involves measuring the rate at which the aircraft climbs and descends in vertical feet per minute at various airspeeds and altitudes. Other tests are designed to measure the speed at which the airplane transitions from bird like to brick like flying (stall tests).
One series of tests involve finding the handling characteristics of the aircraft when it is fully loaded. My airplane weighs a portly 1165 pounds without fuel or people. The maximum weight allowed by the design is 1900 pounds. This leaves 735 pounds for people, fuel, and baggage. The RV-7A can carry at most, 42 gallons of fuel which weigh 252 pounds. That leaves 483 pounds for people and baggage. On the day of this test, I weighed 195 pounds, so I needed to add about 300 pounds. Five 60lb bags of sand is just about right. The bags tend to leak a little so I wrapped them with garbage bags before loading them in to the plane. Four bags in the passenger seat and one in the baggage compartment.
My first passenger: 240 lbs of sand
With full fuel tanks, I was just over gross weight on takeoff at 1912 pounds, but I would be well within gross weight by the time I landed. Take off at this weight was fairly normal if a bit lethargic. I could certainly feel the reduction in acceleration and the climb speed was reduced. In the future, I'll call this heavy sluggish performance, Cessna mode. Just kidding Cessna pilots, just kidding.
Flying around this heavy also placed the Center of Gravity at its rearmost limit. This is why I was only able to place 60 pounds in the baggage compartment that would otherwise take 100. I was somewhat apprehensive about stalling the aircraft at the extreme aft CG, but this is critical data that must be collected. With fingers crossed at 6000 feet, I powered back and gently lifted the nose until, quite suddenly, the plane pitched straight forward and I am in a fully developed stall. The stall recovery was normal: apply power and fly out.
The stall break in an RV aircraft is a bit abrupt as the straight wing stalls along its entire length all at once. There is little to no warning buffet before the break. But if the stall is approached too slowly the plane will begin losing altitude before the break and you enter a mushing descent instead of a stall. Stick full back and losing altitude is a good indication that you're doing something wrong. And, of course, there is also the matter of the stall warning horn blaring.
Once all of the flight tests are complete, the data are collected into a document called the Pilot's Operating Handbook, which is like a manual for this particular airplane. The POH is required to be carried onboard the aircraft as a matter of FAA regulation.
Although I was busy collecting data through some of the forty hours, much of the time I just spent cruising around the valley getting the feel of this airplane and smiling. I did a lot of smiling. Even after forty hours it still hits me every time I fly: I built this thing and it is truly wonderful.
Because I flew many of the phase 1 hours off after work, I was able to fly during the "golden" hour. A photographic term used to describe the first or last hour of the day when the golden hue of sunlight illuminates the landscape and the interplay of long shadows and back lit features combine to make everything look seductively attractive, romantic, and quite literally, picturesque.
It is just impossible not to appreciate the beauty of it all. Two thousand feet above the valley, the sun is just setting over the coastal range propelling streamers of light across green and gold rice patties and furrowed fields in the mosaic laid out beneath. Far below a tractor kicks up a dust trail that glows in the fading light and I wish that I could somehow capture this scene, but I know I can't. Reluctantly, I turn for home and look forward to tomorrow.
In the dim light I descend to my home airport and by the time I push the plane back into the hangar, night has fully enveloped the field. I am satisfied to have completed the data collecting mission if there was one. Otherwise, I'm just happy to have returned safely having collected another life experience.
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