Thursday, August 13, 2020

Vacation, 2020 Style | Part 6, Hot Headed

Last Chance at Lobster

Date Aircraft Route of Flight Time (hrs) Total (hrs)
13 Aug 2020N21481 IWI (Wiscasset, ME) - SDC (Sodus, NY) 3.42139.0

I have often said that the Aviator's Corollary to Murphy's Law is that any landing with an audience will be something less than awesome.

Photo by Tom

That is particularly true when the audience contains a knowledgeable pilot holding a camera. I flared a little too high, came down down hard on the mains, and downward momentum planted the nose wheel. Thus, we thumped-down at Wiscasset, my 205th unique airport, while Tom captured the graceless landing on "film".

Photo by Tom

We pulled alongside Eight Five X-Ray and parked. Tom gathered photographic evidence that my family actually flies with me sometimes.

"Do you think these tie down ropes belong to someone?" I asked, concerned that I was taking someone's tie down spot.

"Naw, they're airport ropes," Tom answered. "There was a Cirrus parked there before, but he probably didn't bother to put the ropes away."

"Yeah, those Cirrus guys are the worst." We shared a laugh over the inside joke. Our good friend Brad owns an SR-20 and we are all secretly jealous of his modern aircraft that was built this century.


We left Eight Five X-Ray and Warrior 481 together at the airport to get re-acquainted.

Using his local traffic knowledge, Tom got us to Sarah's Cafe on US-1 via a back way that mostly avoided the usual traffic congestion. On the way, Tom and Alicia regaled us with the their own tale of rental car difficulties; at least such problems were not unique to us that week.

Red's is on the other side of US-1 from Sarah's, supposedly serving the best lobster rolls in Maine.

We chose Sarah's over the more popular Red's because they offered more seating and were less notoriously prone to long lines. I have never been a big "brand name" guy anyway. Our food was good and I exercised my last chance to get a lobster roll before we put Maine to our airplane's tail. The Bear ordered a shrimp scampi pizza that was so garlicky that it completely changed my long-held opinion that it is impossible to put too much garlic on anything. With that said, it was still really good. Kristy ordered a crab cake and a delicious-looking blueberry soup.

I always enjoy hanging out with Tom and Alicia and, this time, The Bear did not try to steal any of Tom's food.

N1185X made a perfect camera stand for our group photo.

Back at the airport, we noticed that the Cirrus had returned, parked in the next spot over, and reclaimed his ropes. I momentarily imagined the pilot grumpily moving the ropes from under my airplane to the adjacent tie down and had a brief moment of regret, but come on, I had to park next to Eight Five X-Ray.

We said our goodbyes and launched skyward.

Aberration

On climb-out, I remarked to Kristy that the cylinder head temperatures (CHTs) seemed to be climbing faster than usual.

"Should we turn around?" she asked.

"No, I think..." 

As I spoke, the CHT on cylinder #2 hit 450°F, reaching a pre-programmed alarm point that I had set on the JPI EDM-700 engine analyzer sometime around 2008. Although Lycoming indicates that CHT redline for their engines is 500°F, recent work suggests that continuous operation above 400°F is undesirable. Cylinder #3 on my old engine would occasionally crawl above 400°F on a climb, though it never ran that hot at cruise or for any prolonged period of time. In setting the alarm on the JPI, I split the difference at 450°F, intending to set a meaningful alarm point before the heat became too dire, but avoiding nuisance alarms during climbs on hot days.

In twelve years, I had never tripped that alarm. Until now.

Based on telemetry data recorded in ForeFlight, we were just two minutes off the ground when I throttled back, pushed the nose over to increase cooling airflow through the engine compartment, and turned 180° to Wiscasset. These actions brought the temperatures back into a normal range and we flew a standard pattern at low power, landing less than ten minutes after breaking ground. It was my second-ever emergency landing.

Kristy and The Bear disembarked while I consulted with Ray. Because all cylinders were running hot, the likely culprits were ignition timing or running at too lean of a mixture while demanding full power. The latter could suggest an induction leak (affecting all cylinders), low fuel flow, inadequate mixture travel, or a carburetor problem. 

I verified that the mixture control went to the stop on the carburetor when full forward. I also checked the baffling on the engine for good measure.

Focusing on the ignition system, I did some experimental run-ups alone in the airplane to see if the temperature readings were affected by running solely on the Surefly versus the conventional magneto. CHTs do not react quickly and the troubleshooting was inconclusive, though running on one mag versus the other did not produce a discernible effect. 

I did a quick solo test flight to reassess the effect of single magneto operation on CHT while I had high airflow over the engine in hopes that it would make CHT more responsive to ignition changes by hastening equilibrium. Again, this was inconclusive. But I determined that a shallow climb would keep the CHTs reasonably in check.

Meanwhile, Ray talked to Penn Yan and SureFly. Penn Yan was unconcerned about my 450°F alarm, reiterating the Lycoming party line of 500°F being redline. "But isn't a big change like that on an engine cause for concern?" Ray asked. SureFly was responsive, but did not have much to offer.

I explained to Ray that I had observed some aberrant temperature readings earlier in the trip and was certain that something was changing or drifting. Ultimately, I was in no position to do any further troubleshooting in Wiscasset and there was no skilled help available at the airport.

"If you can manage your climb to keep the temperatures under control, get it home so I can look at it," was Ray's final word of advice.

If we were uncomfortable doing that, my other options included staying put (Tom and Alicia offered to host us at their camp) or flying my family home in Eight-Five X-Ray (Tom and Alicia did not need it again until the following week).

After a long discussion with Kristy, we decided to follow Ray's advice. 

But if I was going to fly home, I wanted to be smart about it. If the CHTs got out of control, we would turn around, land at Wiscasset, and explore other options. Our route home (KIWI - GRUMP - KSDC) would pass directly over Brunswick Executive about ten miles west of Wiscasset, which has a full service FBO (FlightLevel). My high school friend Alex lives nearby. Therein lay another backup. We would also pass close to several other airports along the route I chose. By considering the route, we managed some of the risks.

Splitting the Difference between Terrain and Sky

Clouds near Laconia, NH

With a shallow climb, CHTs never exceeded 430°F. Brunswick Executive came and went. In level cruise at 6500 feet, temperatures hovered around 400°F while the engine was leaned at 75% power. Though the temperature was a little higher than normal, it should not have been overly abusive. Had the CHTs begun to increase, I could have reduced power or enriched the mixture.


Clouds at our altitude forced a descent to 5500 feet as we crossed the New Hampshire-Vermont border. Though this cruise altitude may have broken the hemispheric rule, doing so was better than passing too close to the mountain peaks below. (How does one define AGL in the mountains, exactly? For some reason, this did not come up during ground school in flat-as-a-pancake southwest Michigan.) I could have requested a pop-up IFR clearance and climbed above the clouds, but I was not interested in adding IFR complications to the flight, nor was I interested in subjecting Warrior 481 to any unnecessary ascents.


While I was prepared to defend my altitude choice, neither Boston Approach, Boston Center, or Syracuse made any comment about flying westbound at an easterly VFR altitude. 



In spite of it all the flight home was beautiful. I have always been fond of sunbeams, mountains, and dramatic clouds.


Eventually, we reached flatter, lower terrain near Rome, NY and descended to an appropriate 4,500 foot cruise altitude. Through it all, Warrior 481 purred along smoothly without any indications of trouble.

2020 Style

Home again. Photo by Kristy.

In the final analysis, this year's family vacation included:
  • 8.5 total flight hours
  • 1 missing rental car
  • 1 day in a rural ER
  • 1 kidney stone (passed)
  • 1 emergency landing
  • 1 N1185X sighting by ADS-B while in flight over Brunswick
  • 1 valuable object lesson for two teenagers about paying attention to wind while on the water
  • 1 crummy Jeep
  • 2 ridiculously large slides
  • 2 whole lobsters, both with faces (consumed)
  • 2 matching Emma's Lake Placid Creamery t-shirts
  • 3 airports visited (1 new to me, 3 new to Kristy and The Bear)
  • 3 outings for ice cream
  • 4 obvious instances of Mark and/or Dena using the Jedi mind trick on retailers to get free stuff
  • 5 tomes of significant size devoured (metaphorically) by The Bear
  • Some of the best-smelling porta potty hand sanitizer on the eastern seaboard
  • Experiencing beautiful places like Lake Placid, NY and Mount Desert Island, ME
  • Wonderful times with terrific people like Izzy, Dena, Mark, Alicia, and Tom
Clearly, we had some great times, but also some 2020-consistent awfulness. Either way, it all made for some memorable vacation stories and -- most importantly -- everything worked out in the end.

Epilogue

As of this writing, the root cause of the CHT issue remains unidentified. Ray verified that the timing is spot on, that the cooling baffles are in excellent condition, that the JPI EDM-700 temperature readings are accurate, and that the carburetor looks pristine. Through process of elimination, the carburetor remains suspect and Ray has sent it back to Penn Yan for additional testing and inspection.

We'll see what happens. In the meantime, the airplane is down. Again.

Such is 2020.

2 comments:

  1. Bloody engines. Never a dull moment. Sounds like the most amazing trip. Impressed that you’re able to transport all three of you and luggage for a long trip. I need to train my family members in the gentle/dark arts of packing light..... Hope you’re sorted soon.....

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    Replies
    1. The trick is limiting the whole family to one shared suitcase. Now if I can just get my daughter to stop growing...

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