First Flight: N997CZ Takes to the Skies Over Manassas

Watch: First Flight Video

Watch the full first flight video on YouTube →

The Morning Of

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 showing CHT hot zones
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:

CylinderPeak CHT
CHT 1454°F
CHT 2448°F
CHT 3435°F
CHT 4407°F
CHT 5450°F
CHT 6442°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 CHT temperatures during the first flight
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 graph showing stable readings throughout the flight
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 graph showing stable readings throughout the flight
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.

Cockpit photo showing AHRS-1 tumbled on PFD1 while PFD2 remains 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.

Blue skies.

Images: CHT data and flight track courtesy of engine monitor / EFB export, April 11, 2026, KHEF.

Flight 2: N997CZ — Erratic Gauges, an Early Landing, and a Lesson in Crimp Connections

Flight 2 was humbling. I’d walked away from the first flight feeling cautiously optimistic, and I went into Flight 2 expecting to build on that. Instead, it turned into a shorter, more stressful flight than I’d hoped—and it taught me some things I hadn’t anticipated. I’m writing this partly to document what happened and partly because I suspect some of you have run into similar situations. If you have, I’d genuinely love to hear how you handled it.

The flight took place on April 17, about a week after the first flight. Duration was roughly 28 minutes, and I burned 9.5 gallons out of the left tank—a number confirmed when the fuel truck put exactly 9.5 gallons back in afterward, which was a nice validation of the fuel totalizer. The right tank needed just 0.2 gallons, which appeared to be thermal expansion loss. So the totalizer seems to be tracking accurately, which is reassuring.

East Side, Lower Altitude

The first curveball came before I even took off. On Flight 1, we’d been given the west side of the field at 1,800 feet MSL—a comfortable racetrack that kept me away from most of the traffic flow. For Flight 2, the controllers asked me to stay on the east side of the field and would only approve 1,400 feet MSL instead of 1,800.

I get it—they have traffic to manage and can’t always accommodate an experimental doing racetrack patterns wherever it wants. But from a second-flight test perspective, the east side at 1,400 feet gave me a noticeably tighter box to work in. Less altitude, less maneuvering room, and a busier environment. Not ideal, but workable.

There was also a practical cost to working out the airspace coordination on the ground: time. The back-and-forth with the tower while sitting at the hold-short added up, and so did the waits for arriving and departing traffic before I could get onto the runway. By the time I was actually airborne, the engine had been running and sitting far longer than I would have liked—giving the CHTs a head start on warming up before I even had the cooling airflow of flight.

Flight map showing racetrack pattern east of KHEF with altitude trace

The flight map above shows the racetrack pattern east of KHEF. You can see from the altitude trace at the bottom that I stayed in the 1,200–1,600 foot MSL range throughout—tighter than I would have liked, but manageable once the tower and I were on the same page.

CHTs: Elevated at Rotation, Then Trending Down

Cylinder head temperatures were something I watched closely throughout. The chart below shows the full picture.

CHT chart showing all six cylinders exceeding 435°F on takeoff for approximately 3 minutes

The data-logging system flagged this flight with “CHT > 435°F on takeoff for 3 min,” which captures it well. Starting from the ground roll, all six cylinders climbed steeply. By the time I was rotating and in the initial climb, every cylinder had crossed the 435°F red line. The peak cluster—clearly visible in the circled area on the chart—shows the hottest cylinders reaching somewhere in the 460–475°F range, with the leading cylinders at the upper end of that band and CHT4 running a bit cooler than the rest. The elevated temperatures persisted for roughly three minutes before beginning to come back down as the engine found its footing at cruise power.

It was stressful in the moment. Seeing most of your cylinders above redline on a brand new airplane, in a tight pattern at 1,400 feet, is not a comfortable place to be. That said, the temperatures did trend downward on their own, and by the time I reached the cruise portion of the flight, the CHTs had settled back into a more reasonable range—roughly 350–400°F depending on the cylinder.

I’m honestly not certain how much of this is expected break-in behavior versus something worth worrying about. My read from the community is that high CHTs during the initial climb on a new engine—before the rings have seated—are fairly normal. But I’d genuinely welcome input from others who have data from their own early flights. What did your CHT peaks look like at this stage, and how quickly did they improve?

Oil Pressure: Stable and Reassuring

Oil pressure was one of the few systems that gave me no reason for concern. The chart below shows what it looked like across the full flight.

Oil pressure chart showing stable 75-80 psi throughout the flight

During taxi, pressure fluctuated between roughly 50 and 80 psi—normal variation at low RPM. Once I was airborne and at cruise power, it settled into a steady 75–80 psi and stayed there. That was the green band, and it held throughout the flight. Amid everything else that was happening, seeing that line stay flat and calm was genuinely helpful.

The Oil Temperature Problem

This is the main story of Flight 2, and I want to tell it honestly because the judgment calls involved are the kind of thing that’s hard to describe from the outside.

Before either Flight 1 or Flight 2, I had noticed some finickiness in the wiring near the oil temperature probe in the engine compartment. When I moved those wires during preflight work, the oil temp gauge in the cockpit would give erratic readings. I couldn’t reproduce it consistently before either flight, so I logged it as a known issue to investigate and flew anyway. In hindsight, I should have thought harder about what my abort criteria would be if that problem appeared in the air—because it did.

Oil temperature chart showing three erratic off-scale high spikes during the flight

The oil temperature chart tells the story. During taxi, oil temperature climbed gradually from a cold start of around 80°F, rising through the 150s, 170s, and into the 200s by the time I reached the runway—a normal warm-up curve. At takeoff, the real underlying oil temperature was somewhere around 210–215°F, which is in the upper end of the green band and nudging into the yellow caution zone. That in itself was worth noting—warmer than I’d seen in the previous flight, probably a reflection of taking off later in the day.

But the story isn’t the underlying temperature. The story is those spikes.

Three times during the flight, the oil temperature gauge went erratic and shot off-scale high—the near-vertical lines you can see reaching 325–350°F and beyond on the chart. Those aren’t real readings. Oil temperature cannot physically rise at that rate; a genuine spike that steep would mean something catastrophic was happening, not an intermittent wiring fault. I knew intellectually that these were false readings. But there’s a difference between knowing that and feeling okay about it when you’re flying a new experimental airplane in a tight pattern at 1,400 feet.

After the first spike, I kept flying and watched. After the second, I started thinking seriously about returning. After the third—when the gauge went off-scale high and then simply went dark, leaving me with no oil temperature indication at all for a minute or two—I made the call to land early and get it sorted out on the ground.

It’s worth being honest about why that decision felt as significant as it did. In isolation, an erratic gauge on an otherwise healthy engine is a manageable problem. But Flight 2 had been accumulating stressors from the start: a tighter-than-preferred practice area, a lower altitude than I’d wanted, CHTs above redline on takeoff, and now a primary engine parameter going intermittently dark. None of those things individually would necessarily have ended the flight. Together, they made landing early feel like the obvious right call. I wasn’t going to keep flying in a compressed pattern at 1,400 feet with unreliable oil temperature data on a low-time new engine.

I think it was the right decision. But I’d genuinely welcome input from others on how they think through these accumulating-stressor situations. What’s your personal threshold? I don’t always have a clean answer to that.

What Was Actually Wrong

After landing, I went looking for the root cause. In the firewall-forward area, the oil temperature probe wiring is spliced using crimp connectors—four of them joining two wires together. One of those four crimps had not adequately grabbed the wire. I was able to pull it free by hand once I’d unwrapped the bundle.

That was the whole problem. One poorly seated crimp. We re-did it, and the oil temperature gauge worked without issue on every subsequent flight.

The lesson I took from it: a visual inspection isn’t always enough to catch a bad crimp, and an intermittent behavior that shows up on the bench needs to be resolved before flight—not logged and hoped away. I knew about this issue before I flew and didn’t define clear abort criteria for it. I won’t make that mistake again.

A Few Other Notes

PFD-1 (the AHRS-1 attitude indicator) tumbled again on the takeoff roll, consistent with what happened on Flight 1. It seems to correlate with the application of forward acceleration—likely some vibratory effect on the AHRS unit. It’s on the list to sort out, but it’s lower priority than flight-safety-critical items for now. PFD-2 and the G5 standby remained solid throughout.

The Insta360 X5 camera I’ve been using for documentation ran out of battery before the takeoff roll on this flight, so there’s no video to share. I’ll be more deliberate about charging it before future sessions.

What I Took Away

Flight 2 was short and more stressful than I’d planned. But the outcome was fine—nothing broke, I made a conservative decision to land when my instrumentation became unreliable, and we found and fixed the actual problem before the next flight. That’s the process working as it should.

A few things I’m carrying forward:

  • Known issues need abort criteria before departure. If something is behaving oddly on the ground, decide in advance what you’ll do if it shows up in the air. Don’t leave that decision for the moment.
  • Airspace coordination is worth doing ahead of time—and worth holding firm on. Getting assigned the east side at 1,400 feet added unnecessary pressure to an already-demanding flight. For subsequent flights, I’ve made a point to coordinate specifically for the west side of the field. Until I have full confidence in the aircraft and it’s ready to venture further outside the Class Delta for the remaining flight test program, having the more open, higher-altitude practice area on the west side is genuinely important—not just a preference. I’d encourage any experimental builder doing early Phase 1 testing at a busy Class D airport to have that conversation with the tower in advance, and be clear about what you need and why.
  • The fuel totalizer appears accurate. Having the refueled quantity match the totalizer reading exactly was a genuinely useful data point—I’m more confident in that system now.

As always, if you’ve been through something similar—erratic instrumentation on an early test flight, a wiring issue that surfaced at an inconvenient time, or a tricky judgment call about when to land—I’d really like to hear about it in the comments. I don’t have all the answers on this airplane yet, and the conversations here have been more useful than I expected.

Flight 3 is up next.

2021 Annual Condition Inspection

Hobbs: 824.1, Tach: 735.4

Annual Condition Inspection started 2/27/21.

Compression check: 79/78/7878

Removed all wheel pants. Need to replace the right wheel. Left wheel and nose wheel were tires and tubes were replaced last year.

Lubricated aileron hinges, aileron external pushrod rod end bearing, flap lower (external) linkages. Lubricated prop, mixture, throttle, cabin heat, and alternate air push/pull controls both inside the cabin and outside in the engine compartment.

Removed spinner. Greased prop with 6 pumps of grease each side. Inspected bolts and safety wire. Reinstalled spinner.

Removed all baggage items from aircraft. Vacuumed carpet, removed interior carpet. Determined both magnetos had been previously IRAN’ed at 398.7 (left) and 525 (right) Tach times respectively. Current tach 735.4.

Removed 8 spark plugs.

Inspected and took pictures internal to each cylinder of intake and exhaust valves. Replaced all spark plugs with new.

Left wheel pant maintainence

Hobbs: 412.9

Did some maintenance today. Had a sneaking suspicion about the left brake rubbing. Opened left wheel pant since it was just a tiny bit wobbly. Found brake caliper and wheel pant mounting bracket all 3 bolts loose allowing up down motion of whole brake assembly. Removed wheel and tightened bolts. Reinstalled. Noticed this very tiny motion two months ago and we should have checked sooner. Lesson learned: if anything changes even a little bit investigate. Left tire at 22 psi. Right tire at 15 psi!! Filled to 35 each. Since the pressure was low the bulging wheel managed to rub and take another small chunk of the fiberglass wheel pant off on both sides. Trimmed and cleaned a bit more using the sanding wheel in a die grinder on both left and right main wheel pants. Reinstalled both wheel pants. Will test fly it tomorrow AM during instrument lesson. Should probably check nose tire pressure but I didn’t have time before leaving today.

RV7A Maintenance Work – Spark Plugs – 350.5 hours

7/18/18
Good news:
Decided to remove and regap all 8 sparkplugs which made a big difference in ease of starting. Most had gaps bigger than 0.022. Reset to 0.016.
Bad news:
While working around the plane the led work light stand tipped into the wing and put a dent on the top side of the leading edge of the right wing outboard of the fuel tank. It’s smaller than a dime and doesn’t affect airworthiness but I’m feeling pretty bad about it. I plan to research options for removing the dent via auto body service like dent masters or filling the dent with bondo and recovering with a small vinyl patch.