I've had my M4 for close to 3 months now and have flown it about 100 hrs. I really love the plane and I'm really starting to get comfortable in it. However, I have developed a few questions that the "POH" (one put together by a former owner) leaves unanswered. I suppose some experienced Maule guys here may be able to help.

Can you slip it with full flaps?

Can you fly it with both front doors off? Have you done it? POH says one off is ok up to 125 mph.

It doesn't have VGs or elevator gap seal. Is it worth the expense to do either or both? (There are times when I need all the STOL I can get)

For shortest takeoff roll, push the tail up, or come off in 3 point? (firm surface)

It has the Cont IO-360 with GAMIs and a JPI. Sometimes it runs smooth as silk 25* LOP, and sometimes it really starts stumbling just beyond peak. Any ideas why it won't run LOP all the time? The engine really seems to like LOP the times when it gets there. CHTs are running 20*-25* cooler and fuel flow is dropped by 2.5 gph at 25* LOP. Seems to be no in between. It will either do it and run smooth, or it won't run beyond 10*-20* LOP.

Any advice/opinion is welcomed and appreciated.

supermaule, maules.com[Jeremy] and iceman should know. My guess is flaps yes and both doors no.

Good day

Hello RWM,
I have a 1973 M4-210C too, and slip it all the time with full flaps. The POH is very limited for this machine and thats OK. Jeremy could answer the door question for you. I want to remove the back right passenger door for a coyote gunner to ride in the back seat. There is a USDA pilot in Helena that is going to card me and my airplane. As far as the VGs and elevator gap seals goes I got both on mine, but I guess it depends on what kind of flying you do.
Good luck, I sure enjoy my Maule.

James
Clear Creek, Idaho

I'm not a Maule driver, but usually the big deal with slipping an airplane at full flaps and the associated restriction, is the effect it has on the horizontal tail.

The higher the flap deflection, the higher the angle of attack on the horizontal tail. Add some slip (a big component of sidewash on the aft fuselage) into the mix and some airplanes horizontal tail will stall and the airplane will do a bunt. I've heard this is a bad ride when done at altitude, and if it happens on final you are probably a goner.

With the horizontal stalled, the airplane pretty much flies like an airplane where the horizontal tail fell off.

I would practice it altitude for sure before planning on using it much at landing.

I fly a M5-235, pretty much same plane with an ugly tail.

RWM wrote:Can you slip it with full flaps?

Yes, and you should also practice the power off, flaps 40*, elevator all the way up to drop it in. Do some research before you try it in an approach.

RWM wrote:Can you fly it with both front doors off? Have you done it? POH says one off is ok up to 125 mph.

Door off one side only, apparently you don't want any wind through the cabin.

RWM wrote:It doesn't have VGs or elevator gap seal. Is it worth the expense to do either or both? (There are times when I need all the STOL I can get)

Mine had the elevator gap seals but no VG's when I bought it. The VG's make all the difference with this wing, and are a bargain at twice the price. Just do it, you won't be sorry. I bought mine from Alaska Bush wheel.

RWM wrote:For shortest takeoff roll, push the tail up, or come off in 3 point? (firm surface)

I find shortest is to push the tail up, then pop the flaps to 40* and milk them back to 20* for Vx climb out. For me this works best in lower elevations and when light. When I'm heavy at 4000 ft + elevation strips in Idaho it seems to be counter productive and really "wallows" in ground effect a long way. So in those cases it's strictly meat and potatoes. Full throttle with correct mixture for DA, pick up the tail at about 40 mph, rotate at 60 mph and accelerate to Vx for climb out clear of trees +, then milk flaps to 0* and accelerate to Vy.
As with the Bow Flex or Ab cruncher, your results might vary.

Thanks for the response, guys.

James, my POH says back door removal is Ok, as is either front door. However, only one at a time, I suppose. I haven't had any off yet, but it's already hot here and I'm really tempted to try it soon. By the way, what kind of tread you running? Is that and HD or extended gear or did you just pull the covers off? Looks pretty tough.

What does it take to put the gap seal on the M4? Seems I read somewhere that this was a field approval thing...something like that...wasn't designed or STCd for the M4?? Let me know how if I'm thinking wrong. Who sells the actual piece to install?

Not too crazy about getting into a "bunt" from what it sounds like. Not familiar with the term, but it seems like an unfavorable occurrence. Is that something to worry about in the M4? How much control deflection are y'all using in the slip?

Dokmow, thanks for sharing. I under stand the "results may vary" disclaimer. I've never been able to look like the people in the tv commercial. Don't know if my flying will ever look as good as it should either.

The lean of peak question seems to be the elephant in the room. I'm not trying to open up the LOP/ROP debate. I seem to think LOP is a good thing when done right. I'm just wondering if anybody has any insight as to what I might be doing wrong. If any of you are running LOP, I would be interested to know the temps that you use and the results. Really, I would like to know the same info for the ones running ROP, too.

If LOP is a horrible idea in the IO-360, I would like to hear explanations on that as well. A good example of how I have seen benefit (outside of extending range) is with higher ambient temps. A couple days ago, at 4000' msl, I had 3 CHTs between 400*-410* at 50* ROP. I went 25* LOP, ran smooth, and the highest CHT was 385. I've heard as well that 50* ROP is a bad place to be. If I run 100* ROP, the fuel burn is up there and range go to squat. I've spent hours reading on this stuff in an attempt to educate myself, yet I still feel like I don't know what's best for my engine.

I have a fresh engine (<200 smoh with new cyls) and I just want to do what I can to take care of it. I hear this is an expensive one to OH. I haven't gotten much helpful feedback from anyone that I have talked to about how to run this engine. Thanks for any input.

I've been looking at different options for my own self. Sounds like the best thing to do to an M4 is either the M5 or universal wings, then the vg's.???
I am curious how available these wings are and what the cost range would be.
Seems like James is able to do most of the stuff with original wing and affordable mods.
Gary

RWM,
I cruise my IO-360 at 23 squared, and that gives me a real fuel burn of 10 gph. I use the fuel flow gauge more than my EGT and lean it out to 9 gph on my fuel flow gauge, and that equates to about 10 gph. (don't lean too much, replacing jugs is expensive). After flying almost 200 hours this year my compressions were actually better than last year. I also went from running aeroshell 15w50 to strait weight oils in order to save my starter drive $$$$. There is an additive in the multi-grade oils that causes the starter drive to slip.

They install elevator gap seals on the new M-4s so I would assume they are now part of the equipment list. Anyway my M-4 gets me everywhere I want to go with lots of gear too. Check out the gravel bars on the New Brazos River near Mineral Springs, Texas.

PS: if you intend to do much off field stuff, I'd recommend buying the heavy duty Maule gear from Alaska Bushwheel. It isn't cheap, but much better than collapsed gear and your prop in the dirt.

James

Hey James
What are you getting for a true speed @23 squared?
Thanks gary

Gary,
I run mine at 24 squared in cruise and I see 126-128 knots true and 10.5-11.5 gph at lower altitudes. Above 10k I see 130 kts at 9.5 gph. I only have 8.50s on the mains though.
Ross

Hey Ross
That's pretty respectable. What were you flying before you got the M4?
Thanks gary

Super-Maule wrote:RWM,
I cruise my IO-360 at 23 squared, and that gives me a real fuel burn of 10 gph. I use the fuel flow gauge more than my EGT and lean it out to 9 gph on my fuel flow gauge, and that equates to about 10 gph. (don't lean too much, replacing jugs is expensive). After flying almost 200 hours this year my compressions were actually better than last year. I also went from running aeroshell 15w50 to strait weight oils in order to save my starter drive $$$$. There is an additive in the multi-grade oils that causes the starter drive to slip.

They install elevator gap seals on the new M-4s so I would assume they are now part of the equipment list. Anyway my M-4 gets me everywhere I want to go with lots of gear too. Check out the gravel bars on the New Brazos River near Mineral Springs, Texas.

PS: if you intend to do much off field stuff, I'd recommend buying the heavy duty Maule gear from Alaska Bushwheel. It isn't cheap, but much better than collapsed gear and your prop in the dirt.

James

Thanks James. Good point on the new M4 and the gap seals. I'll see what I can find out on that. The HD gear is on the to do list, but will have to wait until my checkbook can catch up.

I saw your helicopter pics on the New Brazos. Looked like a place to have fun for sure! And my M4 has gotten me in and out of a lot of tight spots in our short 100 hrs together.

shortfielder wrote:Hey Ross
That's pretty respectable. What were you flying before you got the M4?
Thanks gary

I flew a straight tail 182s. I had a '57 then a '59. Hard to let that one go, but I really like the Maule. I bought the Maule before I sold the 182, but couldn't keep both. I never had buyers remorse over the Maule, but more like sellers remorse over the 182. The Maule suits me better for my regular flying. A lot of short, rough, and off airport landings. Not quite as good cross country, but not too bad either. In the 182, I got 135 kts true at 12.5-13 gph. It had the Landes fork and 8.00s all the way around.

Ross

Hey James
What are you getting for a true speed @23 squared?
Thanks gary

At 23 spuared my IAS is about 115 to 120 mph and 10 gph. If I run 24 squared I can maybe get 125 IAS in mph but burn 12 gph. 23 squared just seams to be the sweet spot to cruise my Maule. Going from 850s to 29' Airhawks sure slowed me down a lot but sure is invaluable landing on soft fields.

James

I'm about the same... 120 -125 at 24 squared and I too have 29 11 10's on as of about 2 months ago and I'm having a ball with them even though they cost me about 10 MPH cruise... I have VG"s and gap seals which I put on but the VG's were on when I bought the plane years ago... I sold a Tripacer to get it and I put VG's on the tripacer which was one of the best things I did to that plane... so I would venture a guess that the VG's on our Maules are worth every penny as are the gap seals...I can't address the door off stuff cause I never had occasion to want the doors off...if you go for the gap seals let me know as many guys have had problems putting them on and sticking in the wrong places etc... I learned a couple of tricks to get it right the first time...mine have been on for 8 years. I have my back seat out also which makes the plane a little lighter but it's out for cargo room when I go camping and I've had it out since I brought the plane home.. If you do that too make sure you get a W & B done for the rear seat out and keep it in the plane. minor point but important... best and shortest take off method is full power , no flaps, raise the tail as soon as it will come off, then yank full flaps... it'll leap off the ground...then slowly bleed off flaps as you gain speed...do you have the 20/40 degree flap STC and mod... it will help...I have the stock Maule gear but that will change soon when I get the ABW heavy duty gear...and maybe the Maule Bush tail wheel...Yellow Maule in Alaska has our M4 with IO 360 also and he's a good authority.. He once told me to fly it hard and don't baby the engine so I fly it full out most of the time. I know that's not conducive to gas mileage but balls to the wall is how I've been flying it and it hasn't had so much as a hicup in the years I've owned it...as for load carrying... I've loaded the back floor to ceiling back bulkhead to back of my seat with over 200 lbs of camping gear and it's no problem...great little plane....

Gary, I've heard the M5 wings on the M4 are super for short and slow flying but I hardly ever see M5 wings for sale... Wup might know of any for sale or Jeremy...

I talked with Wup and Jeremey yesterday. I don't see why you would put M5 wings on an M4. Why not just get and M5? Bigger engine.2000hrTBO, Cheaper to overhaul, larger fuel tanks, higher gross wt., matching rudder, not that much extra wt. Time you got done swapping, probly not much difference in cost???

I agree, but it was an option when I ground looped and screwed up my left wing.... I wouldn't do it just to do it but if I had to replace i'd consider it...

I have been looking at/considering everything until I find a reason not to. I thought maybe I could do a Bushwacker type Maule, going early/lighter/cheaper and putting newer/longer wing on it. But, doesn't pencil out for me. I really like that Bearhawk. No doubt out of my price range, but sure makes good numbers. Gonna try and beg a ride in Blackrocks at caveman. Maybe trade him for some margs.
I always thought the M5 was a lot of plane for the money, just like the cessna wing.

iceman wrote:I'm about the same... 120 -125 at 24 squared and I too have 29 11 10's on as of about 2 months ago and I'm having a ball with them even though they cost me about 10 MPH cruise... I have VG"s and gap seals which I put on but the VG's were on when I bought the plane years ago... I sold a Tripacer to get it and I put VG's on the tripacer which was one of the best things I did to that plane... so I would venture a guess that the VG's on our Maules are worth every penny as are the gap seals...I can't address the door off stuff cause I never had occasion to want the doors off...if you go for the gap seals let me know as many guys have had problems putting them on and sticking in the wrong places etc... I learned a couple of tricks to get it right the first time...mine have been on for 8 years. I have my back seat out also which makes the plane a little lighter but it's out for cargo room when I go camping and I've had it out since I brought the plane home.. If you do that too make sure you get a W & B done for the rear seat out and keep it in the plane. minor point but important... best and shortest take off method is full power , no flaps, raise the tail as soon as it will come off, then yank full flaps... it'll leap off the ground...then slowly bleed off flaps as you gain speed...do you have the 20/40 degree flap STC and mod... it will help...I have the stock Maule gear but that will change soon when I get the ABW heavy duty gear...and maybe the Maule Bush tail wheel...Yellow Maule in Alaska has our M4 with IO 360 also and he's a good authority.. He once told me to fly it hard and don't baby the engine so I fly it full out most of the time. I know that's not conducive to gas mileage but balls to the wall is how I've been flying it and it hasn't had so much as a hicup in the years I've owned it...as for load carrying... I've loaded the back floor to ceiling back bulkhead to back of my seat with over 200 lbs of camping gear and it's no problem...great little plane....

Thanks iceman,
I'll get VGs on as soon as I have a few extra bucks to spend on it. Guess that will be my next mod.
I didn't know about the 20/40 flap stc. Details?
I would like some guidence on the gap seals. Where to get them, cost, and install tricks.
And I agree...great little plane.

I got mine from Maule in Georgia but Wup at ABW has them too ... When you get them read the directions and when it comes to putting them on , then get a spray bottle filled with water and put about 6 drops of liquid dish washing soap in the bottle... spray the area on your elevator where the tape will go then put the tape in place.. it will slide around some but use a flat putty knife to squeegee out the bubbles and lay the tape flat in place..... you'll have doubts as to whether this works as the tape will slide if you touch it... then go home and come back next day and it will be permanent...if you don't use the spray bottle with the soap you will accidentally touch the tape somewhere and it will stick instantly ..as for the flap STC.. I don't know much about it other than my plane had the mod when I bought it... Factory flap settings were 15 and 30 .. with the stc I have 20 and 40 degrees...