My leaning technique is a lot more basic than yours. I pull back until the engine is so lean that it begins running rough, then enrichen just until it’s smooth again. Next time I fly I’ll actually use the EGTs and find where different FFs are using the book method. I’m more worried about CHTs than anything.
I thought I would try the LOP experiment today but there was so much virga around it was all I could do to keep the shiny side up. It was a 2 head-banger day. Glad I don't have a touch screen navigator on days like this. I was concerned I would pull a knob off the 530W!! The STec did a reasonable job but I turned it off when it was trying to hold altitude and the airspeed dropped below 90 kts!! So maybe another day I will be able to do a good LOP/ROP comparison.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
I knew this would happen. Thanks to these posts I now have some serious panel envy.
I have c$21k for a panel upgrade..
Do I:
a) Put in a GNS750xi with a G5 and use my GNS430 as a backup radio to replace my old NARCO.
b) Strip out the old (but still working) basic AP and replace with a GFC500 and a G5 (may be stretching the budget)
c) Install a fancy EDM-830 like you guys have done.
d) Save my money in the event I need to spend it on something more critical… zzzzzzzzzzzzzz
You already have a very nice panel! It looks great! So here's what I would do. Highest priority: Put in a pair of G5's or an Aspen, which will drive the autopilot smoothly. And I'd put in an 830. By putting in the G5's or Aspen, you'd remove the vacuum system and pickup 30 pounds of useful load. And the 830 would give you something you don't have, peace of mind on your engine. Any money left over can be saved for the next project.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
It looks like he has the stock Piper Autocontrol IIb which needs the vacuum AI to work (this is my situation as well). So the Aspen/G5’s won’t allow him to lose the vacuum system, but they are still a hugely worthwhile upgrade. The G5’s and 830 with labor would be about $15000usd to install.
Jim, I think you have picked up on my issue. I was desperate to get rid of the vacuum pump but my AP is tied to my AH.. I am being told that although the integration is better on the GI275 it still won't do it.. I like your idea about about the 830 and the G5s.. However it still leaves me with a non 8.33 NARCO which is not great in IFR.. But to be fair most of the time I just use it for ATIS! Just wish I had a bigger GPS where I can overlay plates and monitor traffic..
Choices Choices.... Knowing my luck I will make a decision and my AP will go Inop!
Well, if the AP dies, there are some modern options you can consider that will allow you to get rid of the AI and vacuum system. Do you use an iPad? I use an iPad with Foreflight and get my traffic and approach plate overlays that way via a yoke mount. Much cheaper than a new GPS!
I installed an Aspen 1000Pro and it interfaces with my AltiMatic IIIc AP nicely. I previously installed a G5 (HSI) when the HSI bit the dust, but found out when the AI acted up I couldn't use another G5. So the Aspen went in and the G5 is the backup AI, no vacuum system...yea. I've had two vacuum failures in my previous bird...no fun..
I got a chance to compare my LOP and ROP numbers. I will sheepishly admit that what I thought was LOP (based on leaning till the engine was rough, and then enrichening till smooth) was actually right around peak EGT.
25 degrees LOP just doesn’t feel that great (as far as engine smoothness)...but I got great fuel economy and about 123 mph IAS.
Going to 100 degrees ROP and the engine was much smoother, and I gained 10 mph, but my fuel economy was cut down by 25%.
I talked to Mike Busch personally about this a while ago, and in his opinion as long as the CHTs are low and you stay out of the “red box”, it doesn’t matter if you are somewhere in between LOP and ROP. I wonder what the difference is as far as my exhaust system goes running closer to peak EGT?
In any case, here are pics of my engine monitor and G5 with my airspeed for both LOP and ROP.
Scott, How do you calculate maneuvering speed as a function of a/c weight? My Arrow simply has a placard that says maneuvering speed = 134 mph (116 kts).
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
FYI - I installed new Hartzell Prop HC C2YR-1BFP which has a different limitation regarding MP/RPM; Following is my email conversation.
-----Original Message-----
From: Wayne waylau@comcast.net
To: propilotsinc propilotsinc@cs.com
Sent: Mon, Jun 1, 2020 1:23 pm
Subject: Hartzell prop for PA28R-200
Brian, mfg suggested I send you an email regarding my question; limitation for IO 360-C1C and Hartzell Prop HC C2YR-1BFP; continuous operations is prohibitive above 24” mp between 2350 and 2550 RPM.
What is your recommendation as to what is “continuous operations”, typically during cruise climb I would use 25 square and cruise at 24 square up into perhaps 3 or 4 thousand feet. Based on the limitations I should avoid climbing at 25 square.
Can you shed some light. Thanks
Wayne Fiyalko
Hi Wayne,
I normally climb all of my planes at full throttle and 2700 RPM as that seems easier on them than the reduction. That being said, if you want to do the reduction, just use 25 inches and 2550 RPM and you are technically out of the band. 24 squared is fine.. From what I have heard, it would take about 250,000 flight hours inside the band to cause a failure, so take it for what its worth.. I really like to cruise the scimitars at about 2200 RPM and about 24 inches of MP or whatever the performance charts say to use at 75% power. Much quieter, about same speed and much more fuel efficient than 24 squared. Hopefully that helps.
Brian
My Arrow has the C1C6 engine with the Hartzell scimitar prop, no rpm limitations with that engine. I cruise at 2100-2200 rpm and 24" or full throttle, depending on my altitude.
Jim T, my POH has two speeds for Va (maneuvering speed). Gross weight and light weight. It lists as follows:
Design Maneuvering Speed (Va) - Do not make full or abrupt control movements above this speed.
At 2900 LBS, Gross weight: 119 KIAS.
At 1865 LBS, Gross weight 96 KIAS.
Maneuvering speed decreases at lighter weights as the effects of aerodynamic forces become more pronounced. Linear interpolation may be used for intermediate gross weights. Maneuvering speed should not be exceeded while operating in rough air.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
Scott...my POH (aka "owner's manual") doesn't mention maneuvering speed at all. Only the one placard on the instrument panel. Gross weight is 2600 lbs (useful load 1150) but the wings are different therefore I don't see any way to compare the two models. The yellow arc begins at 150 kts IAS for the '69 Arrow 200.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
1969, Arrow 200; IO-360-C1C with straight wing. Gross wt 2600 lbs. Those were the days prior to the FAA mandated "true" POH!!! Thanks in advance if you can find any data. 99.9 % of the time I am solo so the airplane is always very llight which would indicate a lower maneuvering speed that the placard 134 mph. I am almost always at least 600 lbs under gross (~2000 lbs with full fuel)
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
Scott...done!! As soon as we can meet up, of course!! Thanks for the algorithm. This means that for my typical weight of 2000 lbs (max fuel, just me and my own baggage) maneuvering speed would be 102 kts.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
I used to make twice monthly trips from Florida to Texas and back. My placarded Va is 131 mph, but by descent time, it had dropped to 112 mph. This made descending from 8-11,000 ft down to 1000-1300 msl area a careful balance and monitor of airspeed. The old Arrow does love to pick up speed on the downhill!
Remember, Va only applies to a single axis stress event, if you get some twisting going on, airspeed needs to be reduced accordingly. Late afternoon - early evening heating causing some pretty uncomfortable bumpers that was a big deal in the summer.
This was also important when we were teaching glider students. I always made sure they understood the formula that Scott showed.
1974 Arrow II
ATP CFII MEI CFIG A&P AGII FCC GROL with Radar Endorsement
Comments
My leaning technique is a lot more basic than yours. I pull back until the engine is so lean that it begins running rough, then enrichen just until it’s smooth again. Next time I fly I’ll actually use the EGTs and find where different FFs are using the book method. I’m more worried about CHTs than anything.
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
I thought I would try the LOP experiment today but there was so much virga around it was all I could do to keep the shiny side up. It was a 2 head-banger day. Glad I don't have a touch screen navigator on days like this. I was concerned I would pull a knob off the 530W!! The STec did a reasonable job but I turned it off when it was trying to hold altitude and the airspeed dropped below 90 kts!! So maybe another day I will be able to do a good LOP/ROP comparison.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
Thanks for the update, Jim. Fly smoothly
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
If wishes were horses...
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
I knew this would happen. Thanks to these posts I now have some serious panel envy.
I have c$21k for a panel upgrade..
Do I:
a) Put in a GNS750xi with a G5 and use my GNS430 as a backup radio to replace my old NARCO.
b) Strip out the old (but still working) basic AP and replace with a GFC500 and a G5 (may be stretching the budget)
c) Install a fancy EDM-830 like you guys have done.
d) Save my money in the event I need to spend it on something more critical… zzzzzzzzzzzzzz
Ed Powell
You already have a very nice panel! It looks great! So here's what I would do. Highest priority: Put in a pair of G5's or an Aspen, which will drive the autopilot smoothly. And I'd put in an 830. By putting in the G5's or Aspen, you'd remove the vacuum system and pickup 30 pounds of useful load. And the 830 would give you something you don't have, peace of mind on your engine. Any money left over can be saved for the next project.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
It looks like he has the stock Piper Autocontrol IIb which needs the vacuum AI to work (this is my situation as well). So the Aspen/G5’s won’t allow him to lose the vacuum system, but they are still a hugely worthwhile upgrade. The G5’s and 830 with labor would be about $15000usd to install.
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
Jim, I think you have picked up on my issue. I was desperate to get rid of the vacuum pump but my AP is tied to my AH.. I am being told that although the integration is better on the GI275 it still won't do it.. I like your idea about about the 830 and the G5s.. However it still leaves me with a non 8.33 NARCO which is not great in IFR.. But to be fair most of the time I just use it for ATIS! Just wish I had a bigger GPS where I can overlay plates and monitor traffic..
Choices Choices.... Knowing my luck I will make a decision and my AP will go Inop!
Thanks for your ideas..
Ed Powell
Well, if the AP dies, there are some modern options you can consider that will allow you to get rid of the AI and vacuum system. Do you use an iPad? I use an iPad with Foreflight and get my traffic and approach plate overlays that way via a yoke mount. Much cheaper than a new GPS!
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
Another very good point.. Yes I use an IPAD with SkyDeamon which I believe is very similar. What APs are you seeing Arrow owners fitting these days?
Ed Powell
The Aspen unit has an EA100 century autopilot adapter. Want to get rid of the vacuum pump? Put in an Aspen!
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
never new that! Will start investigating. Cheers Scott..
Ed Powell
I installed an Aspen 1000Pro and it interfaces with my AltiMatic IIIc AP nicely. I previously installed a G5 (HSI) when the HSI bit the dust, but found out when the AI acted up I couldn't use another G5. So the Aspen went in and the G5 is the backup AI, no vacuum system...yea. I've had two vacuum failures in my previous bird...no fun..
Thanks for the post and info!
Your experience matches mine perfectly.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
I got a chance to compare my LOP and ROP numbers. I will sheepishly admit that what I thought was LOP (based on leaning till the engine was rough, and then enrichening till smooth) was actually right around peak EGT.
25 degrees LOP just doesn’t feel that great (as far as engine smoothness)...but I got great fuel economy and about 123 mph IAS.
Going to 100 degrees ROP and the engine was much smoother, and I gained 10 mph, but my fuel economy was cut down by 25%.
I talked to Mike Busch personally about this a while ago, and in his opinion as long as the CHTs are low and you stay out of the “red box”, it doesn’t matter if you are somewhere in between LOP and ROP. I wonder what the difference is as far as my exhaust system goes running closer to peak EGT?
In any case, here are pics of my engine monitor and G5 with my airspeed for both LOP and ROP.
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
Of course, having just spent a wheelbarrow full of money on a new engine and prop, are you willing to go LOP?
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
I’ll do whatever it takes to keep the prop spinning smoothly and the CHTs cool! I’m about 75 hours into the new engine and all is perfect so far.
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
Scott, How do you calculate maneuvering speed as a function of a/c weight? My Arrow simply has a placard that says maneuvering speed = 134 mph (116 kts).
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
FYI - I installed new Hartzell Prop HC C2YR-1BFP which has a different limitation regarding MP/RPM; Following is my email conversation.
-----Original Message-----
From: Wayne waylau@comcast.net
To: propilotsinc propilotsinc@cs.com
Sent: Mon, Jun 1, 2020 1:23 pm
Subject: Hartzell prop for PA28R-200
Brian, mfg suggested I send you an email regarding my question; limitation for IO 360-C1C and Hartzell Prop HC C2YR-1BFP; continuous operations is prohibitive above 24” mp between 2350 and 2550 RPM.
What is your recommendation as to what is “continuous operations”, typically during cruise climb I would use 25 square and cruise at 24 square up into perhaps 3 or 4 thousand feet. Based on the limitations I should avoid climbing at 25 square.
Can you shed some light. Thanks
Wayne Fiyalko
Hi Wayne,
I normally climb all of my planes at full throttle and 2700 RPM as that seems easier on them than the reduction. That being said, if you want to do the reduction, just use 25 inches and 2550 RPM and you are technically out of the band. 24 squared is fine.. From what I have heard, it would take about 250,000 flight hours inside the band to cause a failure, so take it for what its worth.. I really like to cruise the scimitars at about 2200 RPM and about 24 inches of MP or whatever the performance charts say to use at 75% power. Much quieter, about same speed and much more fuel efficient than 24 squared. Hopefully that helps.
Brian
I have that same prop and engine combination; I climb at 2600/25” and cruise at 2400/22”.
Jim M.
PA-28R-200
Based at BUU
ATC Chicago TRACON
Thanks
My Arrow has the C1C6 engine with the Hartzell scimitar prop, no rpm limitations with that engine. I cruise at 2100-2200 rpm and 24" or full throttle, depending on my altitude.
I love to defy gravity!
1979 Arrow IV
Jim T, my POH has two speeds for Va (maneuvering speed). Gross weight and light weight. It lists as follows:
Design Maneuvering Speed (Va) - Do not make full or abrupt control movements above this speed.
At 2900 LBS, Gross weight: 119 KIAS.
At 1865 LBS, Gross weight 96 KIAS.
Maneuvering speed decreases at lighter weights as the effects of aerodynamic forces become more pronounced. Linear interpolation may be used for intermediate gross weights. Maneuvering speed should not be exceeded while operating in rough air.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
Scott...my POH (aka "owner's manual") doesn't mention maneuvering speed at all. Only the one placard on the instrument panel. Gross weight is 2600 lbs (useful load 1150) but the wings are different therefore I don't see any way to compare the two models. The yellow arc begins at 150 kts IAS for the '69 Arrow 200.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
Hi Jim,
Refresh my memory, what year and model is yours? I'll see what I can find.
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
1969, Arrow 200; IO-360-C1C with straight wing. Gross wt 2600 lbs. Those were the days prior to the FAA mandated "true" POH!!! Thanks in advance if you can find any data. 99.9 % of the time I am solo so the airplane is always very llight which would indicate a lower maneuvering speed that the placard 134 mph. I am almost always at least 600 lbs under gross (~2000 lbs with full fuel)
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
Jim T: You owe me a drink, lol! Here's the formula!
Current maneuvering speed = max weight maneuvering speed * sqrt (current weight / max gross).
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
Scott...done!! As soon as we can meet up, of course!! Thanks for the algorithm. This means that for my typical weight of 2000 lbs (max fuel, just me and my own baggage) maneuvering speed would be 102 kts.
Jim Torley
CFI-A/I/G
1969 Arrow 200
Based at KFLY (Colorado Springs, CO)
Roger that!
Scott Sherer
Wright Brothers Master Pilot, FAA Commercial Pilot
I used to make twice monthly trips from Florida to Texas and back. My placarded Va is 131 mph, but by descent time, it had dropped to 112 mph. This made descending from 8-11,000 ft down to 1000-1300 msl area a careful balance and monitor of airspeed. The old Arrow does love to pick up speed on the downhill!
Remember, Va only applies to a single axis stress event, if you get some twisting going on, airspeed needs to be reduced accordingly. Late afternoon - early evening heating causing some pretty uncomfortable bumpers that was a big deal in the summer.
This was also important when we were teaching glider students. I always made sure they understood the formula that Scott showed.
1974 Arrow II
ATP CFII MEI CFIG A&P AGII FCC GROL with Radar Endorsement