N997CZ on the ramp at KHEF, ready for Harry’s first flight
Three owners, three pilots — and as of this afternoon, all three have now flown the airplane. Flight 14 was Dan’s first flight; Flight 17 was Harry’s. Harry is no stranger to the family — he’s a partner in our RV-7 too, and a seasoned RV hand — but this was his first time at the controls of the RV-10. I flew the morning’s cruise-and-leaning card solo (Flight 16); in the afternoon I handed N997CZ over, stood out on the ramp with the camera, and watched the third member of the partnership take our airplane up.
The Numbers
Date
2026-06-13 (afternoon)
Engine time
~1.3 hr
Engine hours
23.9 → 25.2
Max altitude
~4,545 ft MSL (4,795 ft GPS)
Fuel used
14.9 gal (totalizer)
Profile
familiarization — no test cards
Conditions
warm afternoon (cruise OAT +63 °F)
No test-card link this time — like Dan’s flight, this was a familiarization sortie, flown rich and relaxed. The cards stayed in the binder.
From the Ramp
Harry took his time with it — a long, unhurried run-up and taxi before rolling, a good 24 minutes of ground time before brake release. That’s exactly how a first flight in a new-to-you airplane should go, and no surprise from someone who already knows his way around an RV.
Harry in the left seat of N997CZ before his first flight in the -10
Harry taxis out for his first flight in N997CZ
The Flight
Harry’s first takeoff in the RV-10
A proper get-comfortable hop: a cruise out to the southwest toward the Culpeper/Orange practice area and back, mostly down low (max ~4,500 ft MSL) and quick — about 167 knots true in cruise, full rich, no leaning. Nothing aggressive: no stalls, no steep stuff beyond gentle 30°-bank turns. Just stick time, getting the feel of the airplane’s weight, trim, and sight picture.
The ground track is a clean out-and-back — none of the test-pattern geometry of a card flight, just a flight with somewhere to go and back.
N997CZ’s Flight 17 ground track — an out-and-back to the southwest toward Culpeper and Orange
A couple of systems notes from the ride. Cabin CO peaked at a benign 6 ppm during the low cruise — worth a mention because it confirms the detector was reading normally, which retroactively makes the flat zero on the morning’s Flight 16 the genuine oddity to keep watching. CHTs ran warm-but-fine on the rich, low-altitude profile (hottest cylinder 430 °F), and the attitude system stayed rock-steady the whole flight — fitting, since this airplane’s long-running attitude saga had finally closed out that same day, with all three sources verified healthy.
Harry taxis in after his first flight in N997CZ
Bottom Line
The whole partnership is now checked out in N997CZ. Harry has the airplane in his logbook, it behaved exactly as it should, and Phase 1 rolls on.
Dan’s new BMW, already wearing the airplane’s callsign.
Let the record show the order of operations: Dan put the tail number on his car before he ever flew the airplane. That’s commitment. (In fairness — he offered the N997CZ plate to me first, before reserving it for his own ride. I passed. He didn’t hesitate.) So when Flight 14 rolled around, the man already had the callsign on his bumper; all that was missing was the airplane in his logbook.
Some context for newer readers: N997CZ has three owners — Harry, Dan, and me. I’ve flown every minute of the test program so far, because that’s how Phase 1 works best: one pilot, one airplane, building knowledge methodically. But thirteen flights and twenty-some hours in, with the stall series done and the systems behaving, it was time. Flight 14 was Dan’s first flight in the RV-10 — his airplane as much as mine.
The Numbers
Date
2026-06-07 (afternoon — second flight of the day)
Engine time
~0.9 hr
Engine hours
18.3 → 19.1
Max altitude
~6,140 ft MSL (6,490 ft GPS)
Fuel used
9.8 gal (totalizer)
Profile
familiarization — no test cards
Conditions
warm afternoon (cruise OAT +76 °F)
No test-card PDF link this time, and that’s deliberate: this was a familiarization flight, not a test sortie. The cards stayed in the binder.
Taxi Out
His first taxi out in the airplane:
Dan taxis out for his first flight in the RV-10.
First Takeoff
And the moment itself — Dan’s first takeoff in N997CZ:
Dan’s first takeoff in the RV-10.Dan in the left seat on the ramp.
What the Data Says About a Familiarization Flight
Even a no-cards flight leaves a data trail, and Flight 14’s log reads exactly like what it was: a thorough, unhurried checkout.
Ground track for Flight 14.Altitude and indicated airspeed — the shaded block is the slow-flight and steep-turn air work.
Air work: a focused fifteen-minute block of slow flight and steep turns. The slow flight walked down to 52 KIAS at ~5,400 feet — comfortably into the regime where this airplane has now been thoroughly characterized — and the steep turns ran to about 45° of bank, pulling a maximum of 1.66 G. Textbook checkout numbers.
Mixture: cruise fuel flow ran about 21 gph — essentially full rich. Thirteen flights of my leaning experiments did not transfer by osmosis; nobody leans aggressively on their first flight in a new airplane, nor should they.
CHTs: the warm afternoon, rich mixture, and lower altitudes made this the toastiest of the weekend’s three flights — cylinder 5 peaked at 428 °F, still under the 435 °F comfort line. All six stayed in the green.
Cabin CO: peak 3 ppm. Benign.
Attitude system: the freshly overhauled AHRS #1, two flights into its tenure, stayed perfectly quiet through all the maneuvering. Not a twitch — the second tumble-free flight in a row, in an airplane that had never logged one before.
Fuel Etiquette
After landing, Dan topped the airplane off on his own dime — about ten gallons. The partnership’s fuel accounting remains in perfect balance, and the totalizer reconciliation thread that runs through this blog barely noticed the handoff.
Bottom Line
Flight 14 added a second name to N997CZ’s pilot roster, and the airplane treated its other owner exactly the way you’d hope: honest slow flight, crisp steep turns, cool-headed avionics, no squawks added. The man had the tail number on his car; now he’s got the airplane in his logbook.
Me? Maybe someday I’ll register a 997RV plate — the partnership’s RV-7 — and close the loop. Then each of us can drive around wearing the other airplane’s callsign, and the fleet will be fully registered on pavement and off.
We had hoped to be wheels-up by 6:30 AM. First flights have a way of humbling your schedule.
The day actually started on time — at around 6:30 AM we were already on the radio with the Manassas tower, working through the coordination that my operating limitations required before I could fly. That conversation shaped the flight plan for the morning. I asked the controller for 1,800 feet MSL inside the Class Delta, offset between one and two miles west of the runway, with north and southbound legs west of the field. It was a compromise altitude — lower than I would have liked for gliding distance safely, but it was as high as we could go inside the Delta without conflicting with Washington Dulles airspace to the north. The tower was accommodating and we had our area sorted.
What we didn’t have sorted quite yet was the aircraft. By the time we’d finished the walkaround, coordinated with the local fire department (who graciously agreed to stand by on-field — something I’d strongly recommend to any first-time experimental flyer), and began taxiing out, it was closer to 8:30. Two hours of pre-dawn nerves, checklists, and quiet conversations on the ramp.
The fire crew’s presence wasn’t just a safety net — it was a reminder of how seriously we were taking this. This wasn’t a routine departure. This was the culmination of years of building, hundreds of hours in the hangar, and a lot of faith in the process.
What Came Before: Engine Time at First Flight
One thing worth noting for anyone following along with their own build: we kept pre-flight engine running to an absolute minimum.
By the time we lined up on RWY34R that morning, the engine had seen just two cold starts and one brief taxi test to break in the brakes — probably less than 10 minutes of total run time prior to the day of the first flight. The conventional wisdom on Lycoming break-in is to get the engine to altitude quickly, run it hard, and let the rings seat properly. So we kept ground time short and intentional. I believe this is also to prevent “gazing” the cylinder walls — a condition that can occur from prolonged low-power operations before the engine is thoroughly broken in, and which can make proper ring seating much harder to achieve afterward.
That philosophy was tested on the morning itself. The long taxi out gave the engine time to heat up, and by the time we completed our run-up, CHTs had climbed to around 405°F — already nudging our yellow warning limit. I made the call to pull back to idle for a couple of minutes and let things cool down before attempting the takeoff roll. It was the right call: temperatures settled, we confirmed everything was in order, and we lined up.
We knew engine temperatures were going to be a story on this flight. We just didn’t fully anticipate how much of a story.
The Flight Area
Per my operating limitations and the coordination with Manassas tower, the first flight was conducted inside the Class Delta airspace, one to two miles west of the runway at 1,800 feet MSL, with north and southbound racetrack legs west of the field.
The altitude was a deliberate trade-off. Higher would have been better for cooling airflow and giving me more options in an emergency, but 1,800 feet was the ceiling we could use without stepping into Dulles’s airspace. You work with what you have.
Flight track over Manassas (KHEF). Red segment marks where CHTs exceeded 435°F — concentrated at the departure end of RWY34R.
Takeoff and Climb: The CHTs Tell the Tale
Liftoff from RWY34R was clean. The RV-10 accelerated exactly as I was expecting — consistent with the seven hours of transition training I’d done with Mike Seeger in Vernonia, Oregon before the build was complete. That experience paid off; there were no surprises on the runway and the controls felt immediate and responsive — more on the flight characteristics in a future post. For now, let’s talk about what the engine monitor was screaming at us.
We had configured our warning limits conservatively for the first flight:
Yellow (caution): 400°F CHT
Red (warning): 425°F CHT
Remember, CHTs were already at around 405°F during run-up, before we even started the takeoff roll. The climb loaded the engine further and temperatures rose quickly.
At 13:01:19 UTC — roughly a minute after liftoff — cylinder head temperatures peaked across the board:
Cylinder
Peak CHT
CHT 1
454°F
CHT 2
448°F
CHT 3
435°F
CHT 4
407°F
CHT 5
450°F
CHT 6
442°F
Five of six cylinders exceeded our red warning limit. CHT1 hit 454°F — well into territory that gets your attention. The aircraft’s engine monitor was painting a very pink picture.
All six CHTs during the first flight. Peak at 13:01:19 UTC with CHT1 reaching 454°F. Temperatures were above 435°F for approximately 2 minutes before trending down.
The good news: we had expected elevated temperatures during break-in, had briefed the scenario, and had a plan. We maintained climb power, kept the nose slightly lower than we might otherwise to maximise airflow, and watched the numbers. Within about two minutes, CHTs began their descent back toward normal operating range and continued to trend down through the rest of the flight as the engine settled in.
Not everything was alarming, though. Oil temperature and oil pressure both told a completely different story — and a reassuring one.
Oil temperature started around 65°F at engine start, climbed steadily through the long taxi, reached roughly 185–190°F by the time we lifted off, peaked at around 195°F shortly after takeoff, then settled into a rock-solid band of 185–195°F for the entire flight — squarely in the green, never threatening the yellow or red zones. Whatever the CHTs were doing, the oil temperature was happy throughout.
Oil temperature throughout the flight. Climbed steadily during taxi, peaked at ~195°F shortly after takeoff, then held a stable 185–195°F band for the duration — solidly in the green zone throughout.
Oil pressure was equally well-behaved. It jumped to around 70 psi immediately at startup, showed some normal variability during taxi at idle power, then spiked cleanly to ~85 psi as full power was applied for takeoff. From there it held a steady ~80 psi through the entire flight — solidly in the green band — before settling back down during the taxi in after landing. On a brand new engine, seeing oil pressure that stable and consistent is exactly what you want.
Oil pressure throughout the flight. A brief spike to ~85 psi at full-power takeoff, then a steady ~80 psi through the pattern — well within the green band for the entire flight.
The flight track map tells the same story geographically — you can see the red segment (CHT > 435°F) concentrated right over the departure end of the runway, fading as we worked through our planned pattern to the southwest of the airport.
One other thing you’ll notice if you watch the cockpit video: the primary flight display — connected to Attitude and Heading Reference System number one (AHRS-1) — tumbled during the takeoff roll. Importantly, this was isolated to screen one. Primary flight display two, connected to AHRS-2, remained solid throughout, as did the G5 standby attitude indicator. So while the artificial horizon on screen one was misbehaving, we had two other reliable attitude references in the cockpit the entire time. The image below captures it clearly — PFD1 on the left showing a wildly incorrect attitude while PFD2 on the right remained perfectly stable.
PFD1 (left, circled) showing a tumbled attitude during the takeoff roll. PFD2 (right, circled) and the G5 standby both remained solid throughout.
Notably, AHRS-1 corrected itself shortly after takeoff — before we even reached the first turn — so the tumble was brief. That said, “it fixed itself” isn’t a satisfying answer for a system you’re counting on, and it’s not ideal, absolutely something that needs to be resolved before any IFR or night flight. It’s sitting lower on the priority list right now while we focus on the engine temperatures. One squawk at a time.
The Builder’s Conundrum: Run It Hard vs. Take It Easy
Here’s the tension nobody talks about enough.
A brand new Lycoming needs to be run like you stole it. Full power, or as close to it as you can manage, for as long as it takes to get the rings to seat against the cylinder walls. We’re talking an hour or two of hard running — sustained high power, letting the pressure in the combustion chamber do the work of pushing those rings out and wearing them in. The payoff is a marked drop in cylinder head temperatures on subsequent flights as the seal improves and the engine breathes properly. You watch for that drop like a hawk.
But running an engine flat-out is exactly at odds with what you want to do with a brand-new airframe. Every builder’s instinct — and the right instinct — is to build up slowly. Fly a little conservatively at first. Take things one step at a time. Get familiar with the aircraft before you start pressing limits.
Those two requirements don’t coexist gracefully.
This isn’t our first rodeo — we previously built and flew an RV-7A (N997RV), and we had elevated cylinder head temperatures on the first several flights of that aircraft too. That experience helps. You know the temperatures are coming, you’ve seen the trend lines before, and you have some confidence that the numbers will fall as the engine breaks in. But it doesn’t make the decision any easier when you’re staring at 454°F on CHT1 and trying to decide how hard to push a machine you’ve spent years building.
What We Learned
A few takeaways that might help others approaching their own first flight:
1. Brief the temperature scenario in advance. We had talked through “what do we do if CHTs spike” before we ever started the engine that morning. That meant when the warnings lit up, there was no panic — just a pre-briefed response.
2. Watch your pre-takeoff temps carefully. The long taxi and run-up had already pushed CHTs to ~405°F before we ever lifted off. That warm baseline mattered. If temperatures had continued to climb during run-up, I would have aborted and tried again later in the day. Knowing your limits — and sticking to them — is the whole game.
3. Keep the new engine ground running time to a minimum — get it flying at high power quickly. The elevated temps during climb are part of that process — uncomfortable to watch, but expected.
4. Coordinate your airspace early. The 6:30 AM tower call was one of the better decisions of the morning. Having the flight area locked in before we even went through the walkaround meant one less variable to manage when we were ready to fly.
5. Set your limits to inform, not alarm. Our conservative warning thresholds (400°F yellow, 425°F red) meant we were informed early. Some builders set limits higher to avoid nuisance alerts; I’d argue starting conservatively and adjusting based on data is the better approach.
6. Have the fire department on standby and mean it. Not as a formality. Talk to them beforehand, make sure they know the aircraft and where you’ll be operating. They were professional, prepared, and I hope we never need them — but knowing they were there made a difference. We also brought them donuts as a bribe, which we highly recommend as part of any first flight preflight checklist.
What’s Next
The RV-10 is now officially a flying machine. Phase 1 flight testing has begun, and there’s a lot of data to collect and share. Future posts will cover:
Flight handling and control harmony
Engine break-in progress and CHT trends over the first 25 hours
Performance numbers vs. the Van’s specs
Lessons learned from the build that showed up on the flight line
If you’re building an RV-10 (or any experimental), I’d love to hear from you. Drop a comment below or reach out directly — the EAA community is one of the best parts of this whole journey.
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