Since more than 830 RV-12s are flying, quite a lot of knowledge has been accumulated regarding what to expect during flight test. Van's provides at the end of the PAP (Production Acceptance Procedure) five flight test cards to accomplish Phase I. It's a task-based approach rather than hours-based and I'm pretty much following what's laid out in the PAP. It's done just like the rest of the PAP, that being check boxes followed by a description of the task (83 check boxes for the first test card alone). Some tasks are simply yes/no, OK/not-OK things, others require numbers to be recorded. The data logging system built into the Dynon HDX helps tremendously. The system records all flight and engine parameters many times per second which are then downloaded to a thumb drive after each flight.
All flight testing is set up to be done solo at a specific total weight. Accurately observing and recording numbers would difficult while also flying the airplane. Thank you Dynon for providing this terrific data logging tool. The FAA now allows, as discussed in the previous post, an additional qualified pilot to assist with Phase I, but so far I'm feeling the urge to keep doing it solo. For some of the tasks I may want a helper, an example being calibration of the AOA gage which requires pushing a button on the EFIS at exactly the stall break while keeping the wings level with rudder. We'll see.
Before getting into the actual flight test, here are a couple of additional thoughts about the first flight. I've done eight flights so far (about 11 hours on the Hobbs) and I've gained some perspective. Here's what I felt I had just done immediately after the first flight:
That's actually Chuck Yeager in a rocket-assisted F-104. Here's what other people probably thought I had done on my first flight:
The first of the five test cards checks to see that all the sensors, instruments and systems are functioning properly. Basic flying qualities are evaluated including trim and straight-ahead 1g stalls. Frankly, considering the complexity of the systems, I'm surprised that everything worked perfectly and the airplane flies so damn well.
After reading the write-ups other builders have done detailing their flight tests, I was fully expecting to have a "heavy" wing as most people do to varying degrees. That's a tendency to roll one way or another with the ball centered and hands off the stick, requiring corrective stick force to counteract the rolling tendency. No heavy wing. The airplane also stalls straight ahead with no tendency to fall off on a wing.
Power-off 1g stalls were done with no flaps, half flaps and full flaps. Because of the surprising numbers I am seeing in the cockpit (confirmed by the data logs) I repeated the stalls in each configuration multiple times on multiple flights. According to a table in Section 5 of the POH, indicated airspeed and calibrated airspeed (corrected for instrument error) are the same. Based on my real-world experience, I find this hard to believe. Theoretically, a Pitot tube would produce about 3.5% error at the AOA seen at stall (~15 degrees) but I've seen larger errors in the lab. Van's does bevel the end of the Pitot in order to mitigate this, so maybe it's true. I just had a discussion with a Van's techs support guy at Oshkosh, and he agreed with me and said he'd check. Strangely, just under the table in the POH showing no difference between indicated and calibrated airspeeds, the very next table shows a difference of about 4 knots between indicated and calibrated airspeeds but with indicated being higher than calibrated for stall speeds in all three flap configurations at a gross weight of 1050 lbf! This would make my numbers even more amazing. Solo with full fuel, i'm right at that weight.
Anyway, even with a few knots error I'm surprised with the numbers I'm seeing. Prior to flying my airplane, I had done stalls in other RV-12s, but it was always with a passenger. For my airplane, built light (735 lbf empty weight), a passenger can easily be 25% of that, having a substantial effect on performance.
Solo, with about 110 lbf of fuel, I'm repeatedly seeing an indicated stall speed of 40 knots with no flaps and 35 knots (!) with half flaps. With full flaps the number is a bit higher, probably because the nose is bobbing up and down and never reaching steady state. The static ports are on the sides of the fuselage a few feet behind the aft edge of the canopy and may be in the turbulent wake from the separated flow at the wing root
Landing, full flaps do add noticeable drag. Half flaps are apparently magic in this airplane and that's the way I land unless I'm high on final -- something I prefer, slipping off any excess altitude. This airplane will sink like a Cherokee (what I learned to fly in 57 years ago!) when slipped with full flaps.
The pic shows me sharing the runway with a bird on short final. My hangar is at Vance Brand Airport (KLMO) in Longmont Colorado, elevation 5040 feet msl. One of the tasks on the first card involved pushing the nose over until I had 120 knots indicated. Starting at our field elevation and climbing a few thousand feet to do the tests, my density altitude has typically been over 10,000 feet. Before doing this, I wondered how close I'd be to Vne (never exceed speed, no doubt based on flutter margins). Many pilots I've known think Vne is indicated airspeed. That's a good way to become no longer counted among the living. Vne is true airspeed, 136 knots on an RV-12. Fortunately, my Dynon HDX displays true airpseed (along with density altitude) so I kept a close eye on it as I did this task. As I slowly approached the prescribed speed, at an indicated speed of 119 knots I bagan releasing forward force on the stick. The computer screamed in my ear "Overspeed, Overspeed." The data log showed I had reached a true airspeed of 136.1 knots. I'd like to never hear that again.
Oshkosh 2026 I just returned from my 37th pilgrimage to aviation Mecca. Although there was a record crowd (around 3/4 million people) it was a bit atypical. As usual, I got there on Sunday (usually one of the best days for watching arrivals) but smoke from Canadian wildfires kept the airplane traffic low until Wednesday. It was still, as always, a sensory overload. Our NASA administrator, Jared Isaacman, flew his personal Mig 29 in.
His personal T-38 was parked beside it. Looking at his accomplishments, I'd say he's an amazing guy.
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