Web Site: http://www.airdorrin.com
Posts by fdorrin:
- Cylinders #1 and #3 peak simultaneously and the fuel flow spread was 0.7 gph
- 8.4 gph will yield 100o ROP at 65% power in this run
- LOP operation: 6.3 gph will get me on the LOP side where all cylinders have peaked and have EGTs declining as we get leaner. This would have been 10o LOP on this test, but Mike Busch doesn’t care where the peak is. CHTs are what matters, and those are all less than 380 in this scenario. Cylinder #4 was the hottest, but I suspect we’ll be more golden there now.
I just came back from a wonderful flight in rain and lowering visibility. It was by no means IFR, but a small step toward lowering my minimums again.
I’ve had pretty high minimums in my airplane for the past year. Mostly because I’ve been distracted while continuously diagnosing issues related the the new equipment I installed. The left engine seemed to be running hot after rebuild, as reported by the EDM 760. The EDM 760 kept giving false alarms related to CHT for a few months, and then fuel flow for the last few.
All that is behind me. I spoke with Lycoming, read the manual, and listened to what my A&P was telling me. The engines have both been running fine with temps that are well within range. I did read Mike Busch on Engines, but much of what he has to stay just doesn’t apply to my smaller lycomings. I spent countless hours trying to reproduced the EGT/CHT relationships and simply couldn’t do it. Now that might of been because I added GAMI injectors and Electro-Air ignition to the mix, but I’m absolutely done thinking about it. Done. My engines are fine.
The engine monitor is finally, finally, reporting all data channels without fail. It took connector replacements to make that happen, but whatever it took I’m happy. Now I’ll use that monitor for accurate fuel management, leaning to a GPH, looking for cylinder anomalies over time, and general engine care. I just wanted it ALL to work. Finally – it does!
So my minimums went high because I recognized the distractions and didn’t fly the practice approaches very well as a result. I have been keeping current, but now I’m refocusing my efforts on driving my PA30 minimums safely back down. You can only do that with practice.
Today, I went flying in the rain. After going to work for a few hours this morning to dig deeper into G280 avionics, I stopped at my hangar and went flying in the rain. It was a short flight in smooth air and lowering visibilities, so my VFR climb to 3000′ was cut short initially. I checked in VFR with Dover and flew the RNAV 27 from BLARE at 2000′ initially. I was able to climb to 3000′ before getting to the final approach course inbound, so the weather wasn’t all that bad.
The altimatic IIIB worked flawlessly, though I decided to step down to 1800′ by the FAF. That meant I would engage LOC mode late, so the vertical guidance did not arm in time for the autopilot to fly us down. No problem – I managed power, retained lateral autopilot, and flew the glideslope manually.
I went missed and flew the RNAV 9, also with vertical guidance. This time I locked and loaded the autopilot and let it do lateral and vertical nav down to circling minimums. During this approach I set up a return IFR flight plan back to Wilmington, and filed while still airborne it as soon as I got a cell signal. I thought it might be tight going back up north in lowering clouds.
The RNAV 9 circle 27 was fun, and I landed out of that just fine. Truth be told, I landed a bit flat, but no bounce.
Taxi back and depart VFR, I picked up my IFR with Dover. The cleared me direct 5000′ and I asked tor and got 3000′. Philly cleared me for the RNAV 27 from Woodstown, but I read the NOTAM that this was out of service. I requested VOR 27 full approach, and flew that to a better landing (long landing to expedite taxi to the West Tees).
This is what I love to do. Take a few hours and go practice approaches in weather. I’ll look for 1000′ ceilings next when there isn’t ice or lightning about. That’ll be a great next step on the way to minimums or misses.
Nice flight today and the airplane, avionics, and autopilot all worked like new.
Comments Off on April 14, 2021 Today, I went flying in the rain
My wife, Beverly, and I just flew down to Maneo (Dare County) airport for the afternoon a few days ago. We enjoyed smooth engines, a 60 kt tailwind, and mostly clear skies on the way down. The airplane is running very well, and with a recent connector replacement, every single data channel on the EDM 760 is finally working. What a pain that has been – running down diagnostics and tolerating false alarms.
Even the autopilot, my 1967 Altimatic IIIb is running great. Hard to believe that it does so well in turbulence. I don’t use the altitude select mode, nor fly the airplane via pitch mode, but everything else works great.
Reaching ZEN on the engines: Now that everything is working in the airplane and the engines are clearly broken in, it was time to rethink how best to operate them. I read Mike Busch, but had difficult reproducing the EGT relationships he describes. Ditto the Cirrus Red Fin crowd. I have come to the conclusion that my small Lycoming engines simply won’t hurt themselves if you keep the heat reasonable.
I’ve been worried about nothing. My A&P has been telling me to just fly the damn things for some time now, but I wasn’t ready to listen. After not being able to apply the ‘new concepts’ effectively, I reached out to my friend Zach – a known Comanche expert, for his thoughts.
I sent Zach charts of actual EGT, CHT, and fuel flow trends from a recent flight. He responded by saying:
Don’t overthink it! In a normally aspirated Lycoming, it is safe to say that nobody has blown an engine up that is designed to run on 91 octane but is running 100LL. It can’t be done! Sure the pressures are higher in the “red box” but they are lower than design, and the engine has lots of margin.
Lean to power loss, enrich to power recovery and that is as good as you’re going to get! Big bore Continentals are different animals with much different characteristics running much thinner strength margins on top ends and the fuel control system is totally different. They are more critical but still not as fragile as they are made out to be.
As far as temps go, EGT raw numbers don’t mean anything except when compared to peak. CHT numbers in a Lycoming are stated by Lycoming that you can’t get any more life or reliability out of the engine if you keep the temps below 435 continuous for high performance and 400 for economy power settings.
That is continuous power not takeoff and climb. If you haven’t done so, download the IO-320 operators manual. https://www.lycoming.
I hope this helps a little. Remember these engines did just fine for many years before anyone started to over analyze things!
This is a guy I trust – so I’m done thinking about it. I’ll keep the temps manageable in the climb and lean to about 8gph in cruise. Thanks Paul and Zach – for the peace of mind.
Comments Off on Apr 9, 2021 – Peace, Harmony, and a Path Forward
2020 sucked for me too. Last month I lost my sister at the young age of 63. She was a smoker and paid the ultimate price for it. Last week I lost my live-in mother inlaw. She lived a good life and was receiving the best care possible here in my home. My wife has been dedicated to her, having lost her father in the last year or so. He had been living with us as well.
So now I’m in a unique situation. We’ve had people living with us since we moved into our home in Chesapeake City. That meant we really weren’t free to enjoy the home or the area as we might have, due to the more important business of senior care. That has all changed at this point, so we are re-arranging the house and starting to go out to dinner more. Bev and I went out yesterday – together – and the house was empty for the first time in 3 years.
What does this have to do with flying?, you ask. Everything, I’d tell you. During the downtime and house arrest, I’ve continued to re-work our airplane to be ready to go flying. N833DF has a new Aspen ProMax, new engines, and freshly overhauled props. All of the squawks have been, and are being, addressed. The squawk list will never ever be zero, however, and it isn’t now with both the 530W and #2 Nav Head giving me trouble. I will, however, not be defeated. I’ll fix and replace as long as I own it!
The Altimatic IIIB is also giving me trouble. It tries to kill me once a year. I get it worked on and it runs great for another 12 months. I’m tired of baby sitting it though, and just watched a video showing the basic features of the STEC 3100. The embedded Cessna 310 pilot video was very well done, and I’ve taken a lesson for them both on not only the equipment, but on video production as well. I want this autopilot!!
So I’ve decided today on my next project. I’m putting a deposit down to encourage the STC process by Genesys. That is, after I get a few basic questions answered. With my existing ProMax investment, I’ll be able to get altitude pre-select, a new Flight Director, IAS and VS vertical speed modes, and a reliable autopilot that is warranted for three full years. I’m so excited.
I also spent some time this morning trolling for places to fly my wife to. She has been a very patient person to set her life aside for both of her parents, and now I’m looking forward to enjoying some time traveling with her.
Most will be 3 day trips or so, built around my work schedule. One will be a longer trip, and we’ll also start planning to make an around-the-CONUS trip over the next few years. No matter what – this is what we worked for.
Fly safe! I’ll get back to posting as my life comes back online.
Out of the bad comes something good.
Comments Off on Jan 2, 2021 – Ready to go Flying!!
These are crazy times. I’m not at all happy with the politics of today, but ready to get on with my life. It will all be fine – the pendulum swings for both sides.
We are still caring for Bev’s mom and scheduling time away continues to be complicated and involve a good number of people and calendars. I also have an ill sister, so I’ve added a bit of travel and logistics to do what I can there as well.
Work is going well and the G280 program is slowly accelerating in activity. My work calendar was recently changed on Friday to include new Monday activity (today), so I’m working with my program manager to not do that to me. The late change in schedule hit several appointments I had made for this week, but we are getting through it.
N833DF flew very well from KILG down to KJGG; Williamsburg-Jamestown airport. This was Bev’s first flight in her airplane in probably 4 years, and it was awesome having her back. I treated her like the VIP that she is, and appreciated the beautiful clear weekend we had ahead of us.
Our actually anniversary is the 9th, and I’m sitting in the Alliance FBO while Lancaster Avionics tweaks my autopilot and replaces my Aspen Pro-Max. Alliance is very nice to accommodate my stay. I’ll complete this blog and hopefully put out another autopilot video while I’m here.
The flight down was smooth at 6000′ and I crossed the field at mid-field for the preferred right downwind to RW13. That runway seems a bit downhill, but it worked out. Turning base, Beverly told me that she hadn’t heard me call ‘Gear Down’. What a partner! So proud of her!
I have been using GUMPS for some time, and reminded her that undercarriage means the same thing. I verified the gear was down and we landed uneventfully. How’s that for her situational awareness after years of not flying! What a girl!
We taxied to overnight parking to tied down and cover the airplane. I made sure to keep Bev safe from airport operations and from the hot props on our airplane as well. It’s been awhile for her, but I very much enjoyed having here there to help unload, cover, and secure.
We didn’t take on any fuel since I had tankered a full load from Wilmington. The car was ready for our overnight, and we loaded it up and were on our way to enjoy walking around on a beautiful day.
Williamsburg-Jamestown airport is in good shape. The runway is aged but good. The taxiway and ramp space has been redone and improved since my last visit as well. I called for a car a few days ago, and that process went without a hitch. The ramp fee was $15 and well worth it. The car only cost me $45, and I think the ability to do this type of day trip is awesome!!
I love this girl! Forgive me the diversion from flying. I’m writing this on the 9th, our 23 anniversary. Beverly is home caring for her mom, and I’m in Lancaster while Lancaster Avionics is working to refine my Twin Comanche’s older autopilot. My wife is directly responsible for my success, and her support and encouragement is why I own an incredibly well maintained PA30.
Williamsburg during the pandemic is lightly populated. Bev suggested we walk everywhere, and we did just that! I’ve finally found a method to lose weight, and walking is helpful in that regard. No breakfast, bread, or beer has helped me lose 15# already, and I feel it is continuing to come off.
The weather was PERFECT. Chowning’s Tavern holds childhood memories for me, but I was disappointed to see a significantly downsized menu. Burgers and bar food was the rule of the day, and the only drink options were sitting out in the sun and completely unappealing. We decided to forfeit our reservation and found a surprisingly good dinner at Sal’s Italian restaurant on the way home.
Sunday morning came with more awesome weather and we walked again. This time we found an excellent breakfast on the main drag, and headed back to the car. We’d pretty much walked ourselves out of energy by the time we reached the car, and decided to fly home a little earlier than planned. The idea was to go out to dinner before resuming our duties for Bev’s mom and sending the help home.
Unfortunately, we were exhausted when we landed. I even put the airplane away and forgot to unload the luggage. I’ll get it tomorrow.
There is so much more to tell, but I’m going to attempt to get another YouTube video out this morning too.
Comments Off on Nov 9, 2020 – Anniversary Flying
Flying has been great! I’ve been flying quite a number of hours per month lately. I’ve also been busy studying for work, learning handgun safety and techniques, dieting and exercise. Exercise has been lacking, honestly, but everything else is going gangbusters.
I am an examiner in both the G280 and Astra at this point, and we just completed our first recurrent client in the G280 program. He left happy and the Wilmington team did a nice job with it. More on that in a subsequent blog.
I did a nice flight to West Virginia with a friend last month to retrieve her mom and bring them both back for a wedding. That flight went very well, but had to wait until I replaced a failing vacuum AI. Done and Done. The Twin Comanche beat airline and driving options to that region handily.
Life gets in the way of the fun stuff occasionally. I have one of the multiple tankless heaters in the house that won’t fire, a new door that has to be cut and installed, a porch construction project about to begin, and several other home projects tanking my time.
My sister is also not doing well, with a serious health issue threatening her future. That is occupying my mind and one of my top priorities for this fall and next year. I will most likely get back to blogging and videos as the fall progresses and a routine develops, but wanted to explain the lack of activity.
Two new videos coming soon to my YouTube channel. The Rae Ann flight and then a subsequent flight where I talk about the use of the Piper Altimatic III B autopilot. I’ll add a blog on the later next – most likely weeks away.
Comments Off on Oct 7, 2020 – Fall Flying
August 10th was a Monday this year – my late mother’s birthday by coincidence. I’ll try to piece the story together of my trip down to Dallas this time, and what I was thinking by the time I got down there (Dallas).
Mid July: I have known I’d be flying to Dallas from Delaware on August 11th for some time now, and had planned to get all my ducks in a row well before hand. The airplane was to be packed and ready, and I’d be well rested the night before for the journey ahead. That was my plan, anyway, but it seems that I would not be in control of my schedule leading up the third big trip down and back. Roadblocks and complications were laid out before me at a pace and in a manner that became laughable.
This is a different man talking to you right now. My boys will tell you that this string of events would have made me loud and miserable 20 years ago. Age, a little wisdom maybe, and a slightly increased amount of patience helped me take everything in stride and keep on moving. I actually started shaking my head and chuckling as each new roadblock stepped in front of me. I knew I’d make safe decisions along the way, and either get there or not.
Let’s walk through it, shall we? I flew back from Dallas after returning from the last trip on July 29th. Before I even started flying back home, I had arranged for my A&P to change my oil in preparation for the next trip, and clean up a few minor squawks. Paul was great about it, so I arranged to have my wife pick me up in Cheswold after I flew the airplane down to him. Getting my wife out of the house is no easy task. She cares for her mother in our home, and we need other people to cover for her if she leaves to help me. This necessity can be a real pain in the ass at times to contend with, but we do.
I left early so I could drop off my oxygen tanks so that they’d be filled for the trip, then I flew the airplane down to Paul’s shop in Cheswold. I flew down there with the understanding that N833DF would be kept in the hangar until the work was done. Then I’d fly it home to avoid any exposure to weather. I’ve had weather damage before, and I don’t leave this airplane out for one day if I can avoid it.
As it turns out, Paul had another Twin Comanche in there ahead of me that he didn’t get finished. N833DF would spend the night on the ramp, but by now I was committed. Just two days prior to my leaving the airplane there, a rare tornado had touched down just a few miles east of this location. I felt good that the odds were with me that another big weather event would not happen again that soon, so I sucked it up and left the airplane there.
The very next day a completely different storm landed another tornado just 25 miles northeast of his location. Really?! That was just a warning shot, I’m sure. I made it through that storm untouched, but the pressure was building to get my airplane home and in my hangar. That pressure was all inside me, but it was there.
After the storm hit, I got a call next from Keen Gas telling me that one of my old oxygen tanks had an expired inspection. Updating that inspection would add a few days, bumping up against my planned departure. The oxygen would have to be a last minute detail, and I the pressure ticked up a bit more.
Friday, August 7th: The airplane was ready to be picked up, but now I had oxygen tanks to retrieved (if they were ready), and then would have to drive south to get my FAA Medical completed. My old AME retired, so I chose a new one down in Dover. I meet the ‘new guy’ and he tells me that he is now retiring too. F#@$ you, and good luck, is what I was thinking. I just smiled and said – ‘Naturally’. I meant it when I wished him well.
So now I’d be driving RIGHT BY MY READY AIRPLANE, but would have my wife’s car down there since mine was in my hangar up north. I can’t drive a car and fly a plane at the same time, so I started to make other arrangements and think this through. I stopped to see if all was ready, and offered to do the leak-test / run-up for Paul. That was a good idea until the clouds turned dark and it started to rain. I drove home and left my airplane there on the ramp. I did at least manage to retrieve my two oxygen tanks on the way home.
Saturday morning, August 8th: Beverly couldn’t help me get to the airplane until late in the day. I asked my son Chris to drive me, and he graciously came over and drove me down. I’d be able to get the airplane home and take my time packing it on Monday night for departure Tuesday morning. Chris and I stopped for breakfast first, and then I had him drop me at the airport. No need to stay, I said, she had new engines and fresh oil and I haven’t had an issue with her since the new engines.
I have my new 2nd class medical and my oxygen tanks. Just no airplane and I’m stuck in Cheswold with no way home. Both of the new temperature probes did get installed, and the oil is fresh.
I paid Paul and spoke with him about the work. The airplane pre-flighted good, so I jumped in and fired up. Holding short of 27, I did the run-up and found that the left electro-air ‘mag’ was not firing at all. Zip. Nada. Paul took a look, checked a few readings, and declared it good. I taxied back out and the same thing happened again. Now I was in Cheswold without a ride. My head hurt thinking about what I’d spent on this mag replacement to have it sit there dead.
Paul was convinced my old toggle switches were just that – too old to be reliable. It didn’t help much that this particular switch had been shorted when he hadn’t tightened it down all the way during the early test flights. The thin silver lining is that these issues do emphasize the modes of failure I might encounter, making me a better pilot in the end.
Paul loaned me his car and promised to come back Sunday to work on it. That’d mean I’d have to arrange a ride back then; work all day Monday; but have plenty of time to get the airplane packed and fueled for the flight Tuesday. The Sunday work turned into Monday, so I knew I’d be working all day before the flight, flying late evening for the post-maintenance, and then flying all the next day. Whatever fat I had in the schedule had evaporated.
Monday evening: I finished working an Astra initial class and drove Paul’s car back to Cheswold and my airplane. I paid Paul and another quality A&P to completely troubleshoot the Electro-Air system and ensure nothing was amiss. I’d be far away from home and didn’t want any complications I could avoid. Everything checked good, so I paid the bill and did the run-up, half expecting the mag to not light up again.
The run-up was fine, and I flew back north to my hangar. Arriving home around 8pm, I ate a late dinner, organized my gear, and called it an early night.
Tuesday morning I start out late, only to be blocked by a train at 6am. I’ve never seen a train before at this hour, and it wasn’t moving. After waiting about 5 minutes, I did a u-turn and took a longer, alternate route.
Arriving at the hangar, I pulled the airplane out and packed it up nicely. Pulling the car into the hangar, I reached for my phone to ensure I’d received the latest expected routing. My hand found no phone clip and no phone. It was sitting on my dresser at home. No question now – I’d be delayed an hour. Do I leave the airplane sitting out and the hangar door open, or do this properly and put it back in the hangar for the round trip home. Keep it professional and safe – I put the airplane back into the hangar, but left the door open. It’d be fine until I returned.
Phone in hand – I am on the return trip back to the airport. I’m not speeding and not pressuring myself to rush. That is a very good thing, because for the first time ever – there is a very large and very slow farm vehicle blocking the entire road. The car in front of me is losing his mind behind it, and decides to go for a pass on a curve. He ends up on the opposite shoulder when oncoming traffic surprises him, which is a sign for me to RELAX. I do just that.
The car is in the hangar now and the hangar is secure. I taxi out to pick up my clearance from ground, since they are open now because I’m delayed. This will be a full route clearance, in the opposite direction I had asked for – north around DC. I launch and talk to Philly, and he sends me south. On the second vector further south I tell him that this makes no sense according to the clearance I’d received. Turns out he still had my original clearance, so he turned me back north again. Wasted fuel. Wasted time. I am surprisingly not flustered yet.
The hits just keep on coming as I realize that the 2 to 3 knot predicted headwinds are going to be 20-35 mph on the nose all day long. I’m also giving away another 8 knots to test LOP, so this is going to be a long trip. LOP is turning out the be an incredible performance booster, so I’m ok with not getting max speed today.
The last roadblock I recorded was due to equipment complications. I was in IMC diverting around storms along the route with 1″ hail. Scanning the panel I noted that the CDI had a 1/2 dot deflection with the autopilot following LNAV. That never happens unless something is not working right. It turns out that my vacuum AI (drives the autopilot) had badly precessed in flight.
Report? Don’t report? I disconnected it in flight and flew by hand for awhile to consider my options. The device righted itself, and I reengaged the autopilot with a vigilant scan for the rest of the trip. It would be overhauled either in Dallas or when I got home – depending.
Further complicating this AI issue when I got to Dallas was a new AD that had come out on the Aspen. If you have version 2.10 or 2.10.1 of the software, and you have no analog backup, you are grounded. That’d be me in this circumstance. Lucky I had version 2.9 installed.
Harrison Aviation is taking great care of me down here. I keep the airplane in a hangar and the airport is well suited for my needs.
I’ll be doing a return flight blog as a companion to the video I just completed, so you can look for that if you have read this far.
Comments Off on Aug 10, 2020 – Prelude to a Cluster Flight
I am doing what I’ve always wanted to do. I retired from engineering and have successfully transitioned to aviation. I’m instructing in jets, and my airplane is in great shape and actively flying. I have no clue how long all this will last, but I’m making the most of it while it does.
I’m still working: I don’t want to explore the gory details here, but we have had a staff reduction. I had taken a voluntary 30 day leave, but came back full time after that. Some of my friends weren’t so lucky, and have since moved on. My interest in this new jet is the reason I’m still working, so I’m happy about that.
One of the things I asked for when I signed up for this, is the ability to fly myself back and forth whenever I need to travel for work. I was thinking Savannah, but have been commuting to Dallas. Kudos to my management for staying with that commitment and supporting my desire to fly. In this environment, I’m even more excited to avoid the commercial flying experience, and supplement that with my hobby – flying myself!
There are some friends really struggling in this virus economy, and I wish them well.
Flying to work: So the really cool thing is that I’m flying the hell out of my new engines. I’ve logged 22 hours in June and another 26 hours in July, with 81 operating hours on these engines as of this writing. I’m ready for LOP ops on the next flight, and really curious what effect that will have on the time it takes to reach Dallas. I expect to reduce the 10 gph per side fuel burn at Rich of Peak to about 7.5 gph Lean of Peak. My range will improve, but at what impact to cruise speed?
Check out one of my favorite videos in the link below. I made this while traveling back and forth to Dallas. I like this one in particular because of the colors, the view out the window, the minor weather challenges I encountered, and what i consider a successful experiment with the time warp video feature on a very long flight. I really like this video, and will use the technique again.
I believe I’ll be flying additional trips to Dallas in August and September. After that time, our sim should be ready and the need for travel should subside. The experience has made me aware of just how capable an airplane this is, and moved one of my goals from being a stretch goal to a very real possibility.
Sitting in my hotel room in Dallas, it occurred to me that flying to Oceanside, CA would take less time than flying home. I have been routinely traveling more than half way across the country a few times a months, and it’s no big deal.
Once I got home, I spoke with Bev about it. We are going to plan an around the country trip to include San Diego, San Francisco. Catalina Island, and Washington State. Then we’ll head back across the country east, with various stops along the way. The difficult part will be deciding where to stop and spend some time, while being careful to avoid the trouble spots.
I’m getting better: As you’d expect, the increased flight activity has improved my performance all around. I’ve noticed my radio work has improved, and that will be reflected in the instruction that I provide. Fuel and Engine management skills have significantly improved, as has my understanding of those systems and subjects, since I now have new equipment to manage. Weather management has been a big deal in the summer heat, and my landings have improved in various conditions as I fly more.
With all this flying, it still has been more than a year since I shut an engine down in training. I was supposed to fly to KXLL last night to do PA30 emergency training in their PA30, but postponed that with the incoming storms. My intent was two-fold. Mitigate the insurance increase everyone expects, and supplement my single engine training. Too late for the former – I got my increase yesterday. Not too late for the later – I’ll get it done over the next two months.
What I need this week, however, is an oil change. I am expecting a call from my A&P today, and will fly down and stay with the airplane when he is available. I’ll either help him or I’ll study while he does the work. He and I can discuss if there is time to swap the probes out as well. I need this done if I’m going to Dallas next week. I’m not a fan of exceeding the 50 hour oil change.
Studying Airplanes: I’m teaching initial ground school in the Astra on Monday, and leaving after that to fly to Dallas to provide sim instruction in the G280. I’ll be doing an initial simulator session to one client.
My study plan is to bone up on G280 Initial SIM sessions first. Review limitations and procedures; ensure my plan and documentation for the client is in order. Once I am satisfied that I’m organized enough to instruct next week, I’ll review the Astra ground school material that I’m more familiar with. Once all that is complete, I’ll review multi-engine and single engine procedures in the Twin Comanche.
Enjoy the day. Fly Safe!
Comments Off on Aug 2, 2020 – What I’ve been looking for
I heard from JPI regarding my replacement temperature probes. I am a bit disappointed that they didn’t run to the mailbox and send out new probes. Instead, they asked me to send them the POs and Invoices and questioned how long I’ve owned them. That made me go back to my A&P and have them do that research for me, which adds times. I gave JPI some lip that they should be able to look that up on their own and not be giving me homework. So far JPI is giving me attitude rather than support.
Reviewing the last GAMI test to harvest more data is fascinating. What the heck did I do without an engine monitor? What was I thinking? Then again – you don’t know what you don’t know.
Here are some interesting tidbits from the left engine I’ve observed that will help set up the next test. It is generally the same for the right side.
The next Test: I wanted to fly after work today, but have since seen that the weather south of us will not be all that great. I’ll wait a bit and do a flight down to Norfolk with a stop on the way back at Georgetown for gas. I’m looking forward to gathering some good intel on how best to operate these engines for allot of flying I have planned in July. I will not be operating LOP operations for this oil change, but I’ll gather data to get ready. Paul suggests I keep it ROP for another 50 hours.
N833DF Test Profile
- Climb to 6000′
- Lean as necessary on the way up to maintain 400o F on all cylinders
- Reaching 6000′ in level cruise, note the OAT against 38o C standard. Plan on adjusting MP (see below for details)
- Set power 24 squared, close cowl flaps, lean to 400o F and note the fuel flow
- Set power 23 squared, closed cowl flaps, lean to 400o F and note the fuel flow
Note: Leave the mixture there as a starting point for the GAMI test
- Begin GAMI Lean Test – one engine at a time
- Open Cowl Flaps
- Verify props to 2300 RPM and MP to 21.6″ +/- OAT adjustment
- Lean slowly (0.2 to 0.3 gph increments)
Note: Test is complete after all EGTs continue to drop as you decrease fuel flow with the mixture
- Determine LOP Range: Continue leaning slowly right up to engine roughness.
- Note the fuel flow. Expect cut-out at 5.7gph
- Enrich to smooth operation. Try 6.0 gph specifically.
That is it for what I’m trying to accomplish. What follows is my thinking behind this profile. if you see a flaw in that thinking, please speak up. I plan to use the video to both share and to supplement the recorded data.
1. ROP Operation: Right off the bat, reaching 6000′ let’s determine what fuel flow looks like for a CHT of 400o F on all cylinders. Keep in mind that fuel injectors, temperature probes, and baffle seals have all changed. Do this for both 24 squared and 23 squared operation.
Note: I see definite improvement in cylinder head temperatures now, but would love to know where the improvements came from. Did the physical repositioning of the probe knock the problem out of the probe or connection for left CHT#4? Did the baffle improvement really drop Cylinder #4 by 30o F? I have to assume at this point that sealing up the air leaks in the baffles made that big difference. Paul did that work on both sides.
Note: without an engine monitor – I’d be flying along and possibly toasting one of my cylinders. Continuously.
2. GAMI Lean Test: This requires a climb to an altitude that ensures I stay at 65% power, the recommended power setting for the GAMI Lean Test. From the PA30 POH, you can see that 6000′ will generally work. From the two charts below I determine that 65% power can be achieved using 2300 RPM and 21.6″ MP, This will keep me just inside the Red Fin for most of the process. I’ll never be in a truly abusive zone with high internal cylinder pressures.
Power (MP) must be adjusted by 0.17″ for every 10o F above standard temps at that altitude, or lower by the same amount for temps below standard. Standard temp at 6000′ is 3o C or 38o F.
The method I will use from the GAMI site is the download method, since I have an engine monitor with integral fuel flow and downloading capabilities. In flight at 2300 RPM and 21.6″ MP, lean very slowly from some point rich of peak EGT to some point where all EGTs are lean of peak. You will know that you are lean of peak EGT on all cylinders once the exhaust temperature of each cylinder continues to drop as you reduce the fuel flow.
I am going to continue the leaning process right through to LOP operation and engine roughness. That will tell me everything – minimum fuel flow at smooth operation LOP; what fuel flow leads to the engine running rough or cutting out; the GAMI fuel spread; and even where ROP fuel flow is. I just need to do it slowly enough to gather meaningful data, all the while keeping CHTs below 400o F.
I’ll publish this post, and then go to the SavvyAviation website and analyze the previous GAMI Lean Test for what it can tell me.
Comments Off on Jun 16, 2020 – N833DF Follow-up Test Profile
Oil Change Complete! I dropped off the airplane yesterday morning, and both Paul and Ralph jumped on the work and completed it in one day. You can see the squawk list on yesterdays blog, so I’ll just focus on the highlights today.
The cowls on both engines were removed and all mounts, mounting points, fasteners, and general conditions were checked once again. Two of the exhaust mounts (straps with metal end caps) were brand new and both failed. These are WEBCO PMA units that run $56 apiece.
The issue was reported to WEBCO. Two new ones were installed and I’ll be looking for money back from them soon. If these new ones fail as well, we’ll get the piper part installed and report the issue. Minor point that doesn’t affect my flying. No other issues were found. No leaks and no looseness.
On the left engine, CHT #3 had been erratic. You can see here that the brown line is CHT#3 zooming up over the red line (450 deg F), and then right back to normal. This was from a flight on June 6th. On other flights, the CHT #3 went to +700 F and right back down to -90 F. At least I knew with great certainty THAT wasn’t happening.
Paul replaced all the connectors in the CHT#3 line to rule out crushed and shorted connections. The character of the anomalies changed for this latest flight, with the CHT dropping to zero, but the issue remains. JPI has been directly asked to replace this probe.
Next up was the issue of the left cylinder #4 being so damn hot that I have to shallow out climbs and reduce power in cruise. On JPI’s suggestion, we swapped the #4 probe and the #2 probe. Now here is where it gets a little sticky. The temperature problem did move to cylinder #2 in that it is now the hottest cylinder. It gets complicated though, as the guys did quite a bit of work sealing up all my new baffles.
With the cowls off, both engine baffle systems were re-inspected and fireproof sealant was added to seal off potential leaks and maximize airflow for cooling. I didn’t expect any noticeable improvement from this, but Paul wanted to try it.
As you can see from yesterdays flight, all temps now are in range and reasonable (except CHT #3 of course). The climb was unrestricted on a hot day and never got much above 400F. Wow! That was nice! I closed the cowl doors for the entire flight.
As a result, I asked JPI to replace both the erratic and the hot probe based on these results. I included the ‘hot probe’ as well because it was just a bit hotter on this flight than previous flights. If they send me only one probe I’ll be ok, since It could reasonably be argued that the sealed up baffles caused the temperature to drop on cylinder #4.
I’m now on 100W oil with CamGuard and have 50 hours to play with it. I’m working in Texas in July, and considering flying. Storm damage is my real concern there, while it sits on the ramp. Both trips are relatively short, and I’m seriously considering avoiding the airlines and flying myself.
No squawks today, other than I left bugs on it last night and the spinners really need to be polished. I’ll get to that work soon.
Fly Safe! Frank
Comments Off on Jun 12, 2020 – Oil Change and Re-inspection
Sorry – I couldn’t resist talking in phases with all this virus stuff still holding us back. I have been busy at work and too lazy to fly after working all day. The heat, humidity, and thunderstorms have been part of that equation too. I cannot blame the winds, as seem to be a bunch gusting to a bunch more every time I open the hangar door. My crosswind skills have been sharpened, but I am tending to land fast all the time. For now, I won’t be getting off at the first taxiway.
So my A&P, Paul, reached out last week to see how I was doing burning hours towards the next oil change. We have some issues to address on the Penn Yan engine work, and in general, and apparently he knew he’d have some time to address them. I had to get moving if I was going to get the full 30 hours in so we could change out of mineral oil.
Where do we stand: Oil consumption has been great. I put in 2 quarts of 100W mineral oil in 30 hours on the right side and 1.5 quarts in 30 hours on the left. Operation has been smooth, which is EXCELLENT!. The climbs, however, must be kept shallow with power reduced fairly soon to manage CHT#4 on the left side. That is an issue that needs to be pursued to a solution. (Suggestions? [email protected])
The GAMI Lean Test results were addressed by the GAMI folks, who sent us two new nozzles for cylinder #4 on both engines (no charge). The new nozzles will increase the heat when ROP, so that means I’ll be even more restricted in climbs if we do nothing else. They’ll run cooler LOP in cruise, so that’ll be good. In any event, I’m only expecting a 5 degree shift either way, per GAMI.
I’ll have to confirm this with Penn Yan and Mike Busch, but I think I can begin LOP operations after this oil change. That may actually resolve the heat issue in cruise, but that remains to be seen. I’ll be conducting another GAMI Lean Test after the new nozzles, to verify the improvement. See the GAMI Lean Test Procedure here.
Paul will be pulling off all the cowls and inspecting mounts, connections, and everything else as a matter of course. While they are all off, I’ve given him a summary of the work I see that needs to be accomplished.
1. Oil Analysis: Blackstone oil analysis starts with this change. Paul suggested waiting one more phase, but I’ll start that now.
2. Left engine Throttle movement restriction: Left engine fuel flow is lower than right. This reduces fuel available for cooling at take-off, exacerbating the already hot cyl #4 issue.
3. GAMI Fuel Nozzles: Install new fuel nozzles per the GAMI lean test
John-Paul Townsend from GAMI writes: On your left engine, #1 peaks first at 7.2 gph and #4 is last at 6.5 gph. That is a 0.7 gph spread. We really want that to be under 0.5 gph. The other two peak at 6.9 gph, so we should make #4 leaner. That will make #4 CHT cooler while you are LOP and warmer while you are ROP, but not more than about 5°F either way. The right engine is almost identical. Two new nozzles are on the way.
4. JPI Repair: I’ve got a definite issue with CHT#3 and a possible issue with CHT#4
Left Cylinder #3 CHT is erratic. JPI suspects crushed wires at a clamp causing a short
Left Cylinder #4 is 30 degrees hotter and requires shallow climbs and open cowl door in level flight. This may be an airflow issue, a Penn Yan issue, a JPI issue, or a GAMI issue. We will eliminate one at a time. Tim Sullivan from JPI recommends:
– Disconnect the one wire from the factory CHT probe on the # 3 cyl. If probe bad or not grounded well, reading can become erratic.
– #4 CHT, leave probes where they are mounted and swap wires with adjacent cylinder, if problem moves the bad probe.
5. Gear door crack: Check small gear door crack near hinge rivet-stop-drill
6. Oil change and general inspection: We’ll be using 100W straight weight oil with CamGuard.
7. Cyl #4 Heat issue: check BAFFLES for the cause of left cylinder #4 heat (air leaks). Take pictures of both engines so I can explain baffles to others. Swap the temperature probes between #2 and #4. Repair the CHT#3 issue.
8. Struts are dirty: Their extension is good, but I didn’t clean them so you could evaluate for leaks.
Running the Engines: Ok – so we know what we’ll be working on. I’m hoping I can get all the squawks out of the way and just focus on CHT#4 being hot. In the mean time though, I needed to run off the remaining hours. As of the last post on May 30th, I had 10.2 hours remaining in the Phase II 30 hour mineral oil run. I began feeling the pressure to ensure I have recent experience in cross country and instrument flights as well, given that I may be taking the wife in our airplane to Florida in July. It’s been too long since I’ve dodged storms and flown actual IMC in this machine, too long.
On June 5th I flew for 2.2 hours with storms in the area and strong winds. I intended to do this flight VFR, mostly due to the storms being embedded at times. The plan was to fly to Ocean City, Maryland for a few practice approaches in VFR. After that I’d fly to Salisbury, Maryland for a few more and then home to Wilmington. I watched the weather as I flew south and it became clear I would’t make it home VFR today.
Since I hadn’t filed a flight plan today, I opted to land at Ocean City and use my phone to file IFR from Salisbury to Wilmington. ForeFlight really improved the iPhone interface to make that easy. I then flew to Salisbury and did an approach there to a low approach, picking up my clearance on the go. It was becoming clear that developing storms in Wilmington might preclude me from getting back home even IFR, so I headed north after only one approach.
Landing at Wilmington was in gusting winds and MVFR ceilings with a storm cell 10nm north of the field. Total flight time 2.2 hours with 0.7 IMC. It began to rain as I closed the hangar door.
On Saturday, June 6th, my wife was busy. My plan was to fly for 2+ hours both Saturday and Sunday, getting closer to the oil change time. Then I found out that my wife had convinced several of her siblings to provide care for my elderly mother in-law on Sunday, and Bev was ready to get out of the house. She is an angel for doing what she does every day, and I wouldn’t think of being busy when she can get out.
I canceled flying for Sunday to make our day out happen, and decided I needed to fly longer on Saturday. I’d been talking with a fellow PA30 owner recently about maybe meeting halfway somewhere for lunch. We are both in the same boat – not having flown the airplanes recently and with voluntarily raised personal minimum. Jim lives in Atlanta, one of my favorite towns. I decided to drop in for a visit. Bev packed me a lunch and I was off.
Storms were expected, and the area was mountainous, but I had that Florida trip coming up and I wanted recent cross country experience. I launched on what would be 8.9 hours of flying, down and back. I made a few mistakes along the way, but the airplane was flawless. I will say I ran the entire trip ROP at reduced power to manage heat. Still made what I consider great time, when you include a stop for cheap fuel in there.
One notable pilot error was stopping for gas at an unfamiliar airport. Cherokee County (KCNI) is in the middle of hills and terrain, and has one hell of a slope landing west (rwy 23). It also has cheap gas, which apparently drew every cessna and piper airplane into it’s pattern. It was a bit distracting hearing all these aircraft (5 or six at once) in the pattern call out ‘Cessna 123 left downwind 23 Cherokee’. By the time I entered the pattern I was number 3 and could only see one of the aircraft in front of me.
I got the gear down early, but my mistake was in NEVER running my GUMPS check. This is part of my nature, but I got busy looking for traffic and it dropped off. I’m working hard to find traffic and two airplanes are waiting to depart. With a start!, I realized my omission on short final and stole a glance out at the mirror to verify gear down. Since I wasn’t looking forward, I didn’t see the runway slope filling my windscreen until the last moment. My landing was reasonable, but I only saved it in the last few seconds (that is what if felt like anyway). On a good note – I heard several compliments like ‘Nice Twin’ on short final. I never looked at the AFD and was not aware of that significant slope. DUMB, DUMB, DUMB.
On Saturday, June 10th, I had completed the Phase II hours and was ready for my oil change. I made the short flight down to 33N, and my wife was freed up to come bring me home. As it turned out, Paul had an emergency and had left the field. He expected me to leave the airplane on the ramp, but I chose not to. Thunderstorms were in the area that night, and expected in the morning. I turned the wife around and flew back home. We’ll figure it out tomorrow.
On Saturday, June 11th, as I write this, the airplane has been delivered. Thunderstorms are expected; winds are gusting as usual; and low clouds are in the area. Wilmington airport has shortened hours, and the tower is closed until 8am. I filed an IFR flight plan for a 7am departure and picked it up easily on the ground with Philly departure. I climbed into the clouds around 1500′, heading for 4000′.
One of the reasons you need recency is learning to trust the instruments and the autopilot. The winds were 30-40 knots climbing through 2000′ and the drift bug and correction angle the autopilot was commanding looked wrong. I was communicating with Philly and watching the systems do their thing, while seriously considering disconnecting the A/P.
I reconsidered, figuring I could monitor course and attitude easily, and take it when I needed to. Instead, I wanted to verify it was working when I needed it to. The approach from that point, including clearance changes for the RNAV 27 into 33N from Blare, was absolutely flawless. I disconnected the automation around 900′ because I was getting bounced around in gusting winds, but flew the needles right to the ground. Good to know what is available in an emergency, and I’m confident I could rely on the airplane to get me where I needed to be.
That’s it for now. If you have the chance to fly an instrument approach before you start your workday – do that. I’m stoked with enough energy to make it fun all day.
Comments Off on Jun 10, 2020 – Phase III Flying