M4 Handling

[1:1 Scale]

I would also suggest putting your plane on some certified/calibrated scales. I'm at the very tail end of a frame up rebuild of my '73 M4-220, and while I haven't done the final W&B yet, we did a preliminary one with all the parts in the cabin, but not mounted, etc. My empty weight came in at 1326. 640 on the left main, 612 on the right, and 74 on the tailwheel, CG at 8.31".

How did I get here? Epoxy primer and Oratex on the fuselage, carbon cowl, wingtips, floorboards, glare shield, panel and front kick panels. Oratex for the interior side panels, no vacuum system, lightweight starter and alternator, EarthX battery located under the front seat (should've at least kept the stock location, if not the stock battery), M5 wings and back seat, and a single screen Dynon HDX panel with an Avidyne IFD-440.

Other than taking out the IFD and maybe going a little bit lighter in the instrumentation department, I don't know where I could save anymore weight. Unless your plane weight through an extensive weight loss program, I can't see your listed empty weight being accurate. Some of the fuselage tubing on earlier M4's was thinner, but I doubt that would be worth much weight savings. Maybe the scales I used read high- that would be pretty awesome....

[Dkuber]

CG 10.7
Empty is listed 1400 but that was before I stripped out the second interior (mine came with one added over original) as well as a bunch of other lightening up things, inc vac removal. Still need to re-weigh it at some point.

Battery is under seat, came that way.

Engine is 300lbs dry as setup. Few pounds heavier than io360 but marginal.

I do know of 2 m4-210’s @1220lbs

[Flyjohnny]

CG 10.7
Empty is listed 1400 but that was before I stripped out the second interior (mine came with one added over original) as well as a bunch of other lightening up things, inc vac removal. Still need to re-weigh it at some point.

Battery is under seat, came that way.

Engine is 300lbs dry as setup. Few pounds heavier than io360 but marginal.

I do know of 2 m4-210’s @1220lbs

I did notice one of your other posts on battery re-location where you posted a pic. I am really interested in moving the battery under the seat but can't find any paperwork that states it is allowed for the M4 210-C. I do see it for the 180 and 220 models. Other option I am considering is waiting for EarthX to finalize an STC for the Maules and going that direction.

Yeah like I mentioned, my plane is pretty bare bones. No vacuum system, only 4 flight instruments and one radio so definitely helps to keep the weight down.

[1:1 Scale]

I imagine that your Franklin will be a bit heavier than min IO-360 bringing the weight forward a bit. I also have very little avionics.

I know this wasn't directed at me, but from what I found in a quick google search, there isn't much difference in weight between the Franklin and IO-360. 297 lbs. for the Franklin, and 296-332 for the IO-360. That leaves some room for some accessories that that may not have been on the Franklin that were on the Conti, but I'd say their about equal.

I was hoping to get to 1200 lbs. on my build, without it being completely stripped, and remaining IFR capable. There might be a few lbs. left on the table, but there's no way there's an extra 100 lbs.

[Flyjohnny]

I imagine that your Franklin will be a bit heavier than min IO-360 bringing the weight forward a bit. I also have very little avionics.

I know this wasn't directed at me, but from what I found in a quick google search, there isn't much difference in weight between the Franklin and IO-360. 297 lbs. for the Franklin, and 296-332 for the IO-360. That leaves some room for some accessories that that may not have been on the Franklin that were on the Conti, but I'd say their about equal.

I was hoping to get to 1200 lbs. on my build, without it being completely stripped, and remaining IFR capable. There might be a few lbs. left on the table, but there's no way there's an extra 100 lbs.

Yes I apologize, I also did some searching and noticed that the Franklin and IO-360 are pretty close in weight. I am used to comparing the Franklin to my old O-360 I had in my Stinson.

Just wondering where is you battery located?

I am not sure why everyone insists that I re-weigh my airplane, there is nothing to suggest that the scales were not certified and if anything I can guarantee that since the plane was last weighed last it would definitely be even lighter as I have removed more equipment and furnishings. The specs all show this plane coming out of the factory at less than 1300lbs. The whole reason I made this post wasn't to argue about how much the M4 weighs, it more in the line of how it flies with a rearward C of G. I am really trying to find out if other M4 drivers find that the plane gets quite pitch sensitive with an aft C of G. I know a few people that own Bearhawks that is closely designed after the M4 and although they are generally more nose heavy with the larger engines they put in, they are known to be pitch sensitive with aft C of G. Sorry if I misled people with my original post but in the end I am really trying to find out if these are normal flying characteristics for the M4. Also, yes I realize what an aft C of G generally does to the performance of a plane. Like I mentioned in my original post, I have have 33 years of flying experience commercially and over 18,000 hours on all types big and small. I just want to find out if this is something unusual to the M4 and if other owners have found anything that has made a noticeable improvement. ie battery re-postitoning.

I do really appreciate everyones help and input and do not want to discourage anyone from commenting. I am new to the Maule brand and am very keen to learn as much as I can about all the different models.

Thank you again and please keep the comments and suggestions coming.

[Andy Young]

I understand your frustration: you asked a specific question, and have yet to get a reply to that question. That’s certainly one my own pet peeves.

What you HAVE gotten is some good faith efforts on the part of the community to address the symptom that caused you to ask your question in the first place.

The reason so many are suggesting you re-weigh the plane is:

1. Amongst this very Maule-experienced group, it appears that no one has seen numbers that come close to yours, so they are naturally suspicious of those numbers, and

2. If your numbers are closer to typical for your model, the loading you describe could indeed put you aft of the CG limit, causing exactly the symptoms you describe.

No one has chimed in to say that M-4s are twitchy near (but within) the aft CG limit, so I’m guessing no one has experienced that. In other words, your answer is there, in the lack of replies in the affirmative. I’m a bit surprised that no one has mentioned personal experience with actually being aft of the aft limit, but maybe no one wants to admit on a public forum to having done so. I can’t help on that score, as it’s near impossible to get a 540-equipped Maule aft of the aft limit.

[firstmaule4]

Back to your question about it being pitch sensitive no when loaded within my cg envelope 40 gallons fuel 2 adults (165lbs and 159lbs) 2 kids (65 80) and baggage (40)no it does not fly different however landing you notice tail heavy but all controllable But regular speed nothing different.

[Kirk]

Regarding your original question; no, the handling you describe is not normal.

Kirk

[1:1 Scale]

I imagine that your Franklin will be a bit heavier than min IO-360 bringing the weight forward a bit. I also have very little avionics.

I know this wasn't directed at me, but from what I found in a quick google search, there isn't much difference in weight between the Franklin and IO-360. 297 lbs. for the Franklin, and 296-332 for the IO-360. That leaves some room for some accessories that that may not have been on the Franklin that were on the Conti, but I'd say their about equal.

I was hoping to get to 1200 lbs. on my build, without it being completely stripped, and remaining IFR capable. There might be a few lbs. left on the table, but there's no way there's an extra 100 lbs.

Yes I apologize, I also did some searching and noticed that the Franklin and IO-360 are pretty close in weight. I am used to comparing the Franklin to my old O-360 I had in my Stinson.

Just wondering where is you battery located?

I am not sure why everyone insists that I re-weigh my airplane, there is nothing to suggest that the scales were not certified and if anything I can guarantee that since the plane was last weighed last it would definitely be even lighter as I have removed more equipment and furnishings. The specs all show this plane coming out of the factory at less than 1300lbs. The whole reason I made this post wasn't to argue about how much the M4 weighs, it more in the line of how it flies with a rearward C of G. I am really trying to find out if other M4 drivers find that the plane gets quite pitch sensitive with an aft C of G. I know a few people that own Bearhawks that is closely designed after the M4 and although they are generally more nose heavy with the larger engines they put in, they are known to be pitch sensitive with aft C of G. Sorry if I misled people with my original post but in the end I am really trying to find out if these are normal flying characteristics for the M4. Also, yes I realize what an aft C of G generally does to the performance of a plane. Like I mentioned in my original post, I have have 33 years of flying experience commercially and over 18,000 hours on all types big and small. I just want to find out if this is something unusual to the M4 and if other owners have found anything that has made a noticeable improvement. ie battery re-postitoning.

I do really appreciate everyones help and input and do not want to discourage anyone from commenting. I am new to the Maule brand and am very keen to learn as much as I can about all the different models.

Thank you again and please keep the comments and suggestions coming.

I apologize for focusing on the empty weight, it's just that that's where I'm at right now. Just did my final weigh in yesterday, and came in at 1326 lbs. 632 on the left main, 616 on the right, and 82 on the tail. Enough interior to keep it "civilized", but I didn't put anything in that I didn't think was necessary. I also have the Airframes Alaska aluminum struts, which are a relatively new offering and save a claimed 9 lbs. So my personal experience, after chasing a 1200 lb. goal after seeing it mentioned on here, and using some lighter materials in some places, is that not all scales appear to be calibrated equally In fact, one of the four scales in the set I used read 10 lbs. lower than the other three when I stood on them individually. I didn't use that one. Maybe I should've so I could carry another 10 lbs....

My battery is located under the right front seat.

In regards to handling, also having owned a Stinson 108-1 prior to the Maule, is that my M4 was much more pitch sensitive than the Stinson. I can't say off the top of my head how far back I've had the CG, but even with just two up front, it felt like the elevator was "over balanced" aerodynamically. The Stinson had much better control harmony.

Also, there was a Maule document in my stack of paperwork that was used as an example of how to calculate the CG, and I mistakenly thought that it was the original W&B for my airplane from the factory. It had the empty weight at something like 1313 lbs. I found it after doing my initial weigh in, so imagine my shock and amazement that my plane had GAINED 13 or so pounds after my "weight loss" program and all the money I had spent on lightweight components and materials! I brought it up to Ty at the factory, and he helped me figure out what it actually was

[Flyjohnny]

I know this wasn't directed at me, but from what I found in a quick google search, there isn't much difference in weight between the Franklin and IO-360. 297 lbs. for the Franklin, and 296-332 for the IO-360. That leaves some room for some accessories that that may not have been on the Franklin that were on the Conti, but I'd say their about equal.

I was hoping to get to 1200 lbs. on my build, without it being completely stripped, and remaining IFR capable. There might be a few lbs. left on the table, but there's no way there's an extra 100 lbs.

Yes I apologize, I also did some searching and noticed that the Franklin and IO-360 are pretty close in weight. I am used to comparing the Franklin to my old O-360 I had in my Stinson.

Just wondering where is you battery located?

I am not sure why everyone insists that I re-weigh my airplane, there is nothing to suggest that the scales were not certified and if anything I can guarantee that since the plane was last weighed last it would definitely be even lighter as I have removed more equipment and furnishings. The specs all show this plane coming out of the factory at less than 1300lbs. The whole reason I made this post wasn't to argue about how much the M4 weighs, it more in the line of how it flies with a rearward C of G. I am really trying to find out if other M4 drivers find that the plane gets quite pitch sensitive with an aft C of G. I know a few people that own Bearhawks that is closely designed after the M4 and although they are generally more nose heavy with the larger engines they put in, they are known to be pitch sensitive with aft C of G. Sorry if I misled people with my original post but in the end I am really trying to find out if these are normal flying characteristics for the M4. Also, yes I realize what an aft C of G generally does to the performance of a plane. Like I mentioned in my original post, I have have 33 years of flying experience commercially and over 18,000 hours on all types big and small. I just want to find out if this is something unusual to the M4 and if other owners have found anything that has made a noticeable improvement. ie battery re-postitoning.

I do really appreciate everyones help and input and do not want to discourage anyone from commenting. I am new to the Maule brand and am very keen to learn as much as I can about all the different models.

Thank you again and please keep the comments and suggestions coming.

I apologize for focusing on the empty weight, it's just that that's where I'm at right now. Just did my final weigh in yesterday, and came in at 1326 lbs. 632 on the left main, 616 on the right, and 82 on the tail. Enough interior to keep it "civilized", but I didn't put anything in that I didn't think was necessary. I also have the Airframes Alaska aluminum struts, which are a relatively new offering and save a claimed 9 lbs. So my personal experience, after chasing a 1200 lb. goal after seeing it mentioned on here, and using some lighter materials in some places, is that not all scales appear to be calibrated equally In fact, one of the four scales in the set I used read 10 lbs. lower than the other three when I stood on them individually. I didn't use that one. Maybe I should've so I could carry another 10 lbs....

My battery is located under the right front seat.

In regards to handling, also having owned a Stinson 108-1 prior to the Maule, is that my M4 was much more pitch sensitive than the Stinson. I can't say off the top of my head how far back I've had the CG, but even with just two up front, it felt like the elevator was "over balanced" aerodynamically. The Stinson had much better control harmony.

Also, there was a Maule document in my stack of paperwork that was used as an example of how to calculate the CG, and I mistakenly thought that it was the original W&B for my airplane from the factory. It had the empty weight at something like 1313 lbs. I found it after doing my initial weigh in, so imagine my shock and amazement that my plane had GAINED 13 or so pounds after my "weight loss" program and all the money I had spent on lightweight components and materials! I brought it up to Ty at the factory, and he helped me figure out what it actually was

Thank for your reply on this subject, I really appreciate your info and was happy to hear that you owned a Stinson in the past for comparison. Is there anyway you could send me a copy of your paperwork and plans for moving the battery forward under the seat. Strongly considering doing that this spring.

Thanks again.

[maules.com]

There is an AD on attachment of the leading edge carry through tube of horizontal stabilizers.
I wonder if some repair in the past has changed things.
There is also a SB on the tailplane tube attach point that could change things

[1:1 Scale]

Thank for your reply on this subject, I really appreciate your info and was happy to hear that you owned a Stinson in the past for comparison. Is there anyway you could send me a copy of your paperwork and plans for moving the battery forward under the seat. Strongly considering doing that this spring.

Thanks again.

I'm still waiting to get everything back from the FAA, but we referenced Maule drawings 1256B Rev. B. and 7042F Rev. D.