Sealing the baffles (round 2)

The elevated CHTs on first flight caused me to go back and seal the baffles with even more care. I used EAA tech counselor’s recommendation of siliconized latex caulk to seal the baffles. I hope this stuff holds up to heat the way the tech counselor promised.

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First Flight Cylinder Head Temps

During my first flight of 0:28, I flew at reduced throttle settings and prop full forward (high RPM). This is not really recommended for several reasons: 1) the throttle full forward enables an enrichment path that increases fuel flow and helps to cool the engine during breakin, and 2) for engine break-in you want to fly with 65-75% power for the first 5+ hours to ensure you seat the rings. By flying with reduced throttle settings, i bypassed the enrichment circuit and had higher CHTs (or this is my working theory).

The desire is to have CHTs during climb stay below 400 F and CHTs during cruise in the mid 300’s. My CHTs peaked at 434 F during climb and were in the mid 300’s during my low power circuits around the pattern.

On my second flight, the goal is to fly full rich, and possibly pull back on the prop control to keep airspeeds reasonable while still enabling the full throttle enrichment feature. My airspeeds during first flight never exceeded 115 KIAS, but with these settings for my second flight I may see airspeeds > 150 KIAS and will need to be ready for the rapid pace in the KHEF class D (4 nm radius).

It is quite the dilemma for the 2nd flight. KHEF class D has a ceiling of 2000 MSL and 4nm radius. Warrenton airport (8 miles away) is outside the Washington DC SFRA and I could have unlimited altitudes out there. Should I depart the proximity of manassas in exchange for the added safety of extra altitude available near warrenton, but risk the 8 nm flight between the two airports during flight 2? Current plan is to wait till flight 3 for that. I will try to fly flight 2 inside the KHEF class D at higher power settings.

You can see the advice I got from Vans Airforce here:VAF First Flight Post

First Flight

First flight occurred on Black friday, just after thanksgiving 2015. Initial preparations began at 06:30:

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I asked my ground crew to arrive at 7AM.

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My ground crew for the first flight consisted of my brother Steven, Greg Mitchell (volunteer rescue squad member), Dan Havens (rated private pilot familiar with Manassas airport), and Mark Gramann (good friend in town for Thanksgiving). My wife Rachel and 8 month old Zack were also present.

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For gear, I wore my road rally racing fire suit, nomex socks, nomex hood/balaclava, work gloves (nomex ones hadn’t arrived), and regular tennis shoes. I carried a 1.3 lb. halon fire extinguisher, a small hatchet (to help if I needed to break the plexiglass window to extricate myself from the airplane), an aviation handheld radio, and smoke goggles in a duffel bag I strapped to the passenger seat.

Ground gear consisted of a 20 lb. chemical fire extinguisher, Greg’s fire axe, Greg’s rescue sawzall (used on car extractions for cutting A/B pillars), a hand held aviation radio, and a 4 wheel drive vehicle.

We performed a preflight briefing and I provided the crew with maps of the airport and surrounding area, local tower and ground frequencies, and a gate card to let in the local rescue squad if required. Greg contacted Manassas City Fire & Rescue and we learned that they knew how to access the airport perimeter and had a 3-5 minute estimated response time to the airport.

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